Paul E. McKenney [Tue, 26 Sep 2017 03:19:02 +0000 (20:19 -0700)]
rcu: Remove extraneous READ_ONCE()s from rcu_irq_{enter,exit}()
The read of ->dynticks_nmi_nesting in rcu_irq_enter() and rcu_irq_exit()
is currently protected with READ_ONCE(). However, this protection is
unnecessary because (1) ->dynticks_nmi_nesting is updated only by the
current CPU, (2) Although NMI handlers can update this field, they reset
it back to its old value before return, and (3) Interrupts are disabled,
so nothing else can modify it. The value of ->dynticks_nmi_nesting is
thus effectively constant, and so no protection is required.
This commit therefore removes the READ_ONCE() protection from these
two accesses.
Link: http://lkml.kernel.org/r/20170926031902.GA2074@linux.vnet.ibm.com
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Shu Wang [Tue, 12 Sep 2017 02:14:54 +0000 (10:14 +0800)]
ftrace: Fix kmemleak in unregister_ftrace_graph
The trampoline allocated by function tracer was overwriten by function_graph
tracer, and caused a memory leak. The save_global_trampoline should have
saved the previous trampoline in register_ftrace_graph() and restored it in
unregister_ftrace_graph(). But as it is implemented, save_global_trampoline was
only used in unregister_ftrace_graph as default value 0, and it overwrote the
previous trampoline's value. Causing the previous allocated trampoline to be
lost.
kmmeleak backtrace:
kmemleak_vmalloc+0x77/0xc0
__vmalloc_node_range+0x1b5/0x2c0
module_alloc+0x7c/0xd0
arch_ftrace_update_trampoline+0xb5/0x290
ftrace_startup+0x78/0x210
register_ftrace_function+0x8b/0xd0
function_trace_init+0x4f/0x80
tracing_set_tracer+0xe6/0x170
tracing_set_trace_write+0x90/0xd0
__vfs_write+0x37/0x170
vfs_write+0xb2/0x1b0
SyS_write+0x55/0xc0
do_syscall_64+0x67/0x180
return_from_SYSCALL_64+0x0/0x6a
[
Looking further into this, I found that this was left over from when the
function and function graph tracers shared the same ftrace_ops. But in
commit
5f151b2401 ("ftrace: Fix function_profiler and function tracer
together"), the two were separated, and the save_global_trampoline no
longer was necessary (and it may have been broken back then too).
-- Steven Rostedt
]
Link: http://lkml.kernel.org/r/20170912021454.5976-1-shuwang@redhat.com
Cc: stable@vger.kernel.org
Fixes:
5f151b2401 ("ftrace: Fix function_profiler and function tracer together")
Signed-off-by: Shu Wang <shuwang@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Steven Rostedt (VMware) [Thu, 21 Sep 2017 17:00:21 +0000 (13:00 -0400)]
tracing: Remove RCU work arounds from stack tracer
Currently the stack tracer calls rcu_irq_enter() to make sure RCU
is watching when it records a stack trace. But if the stack tracer
is triggered while tracing inside of a rcu_irq_enter(), calling
rcu_irq_enter() unconditionally can be problematic.
The reason for having rcu_irq_enter() in the first place has been
fixed from within the saving of the stack trace code, and there's no
reason for doing it in the stack tracer itself. Just remove it.
Cc: stable@vger.kernel.org
Fixes:
0be964be0 ("module: Sanitize RCU usage and locking")
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Suggested-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Steven Rostedt (VMware) [Fri, 22 Sep 2017 21:36:32 +0000 (17:36 -0400)]
extable: Enable RCU if it is not watching in kernel_text_address()
If kernel_text_address() is called when RCU is not watching, it can cause an
RCU bug because is_module_text_address(), the is_kprobe_*insn_slot()
and is_bpf_text_address() functions require the use of RCU.
Only enable RCU if it is not currently watching before it calls
is_module_text_address(). The use of rcu_nmi_enter() is used to enable RCU
because kernel_text_address() can happen pretty much anywhere (like an NMI),
and even from within an NMI. It is called via save_stack_trace() that can be
called by any WARN() or tracing function, which can happen while RCU is not
watching (for example, going to or coming from idle, or during CPU take down
or bring up).
Cc: stable@vger.kernel.org
Fixes:
0be964be0 ("module: Sanitize RCU usage and locking")
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Steven Rostedt (VMware) [Fri, 22 Sep 2017 21:22:19 +0000 (17:22 -0400)]
extable: Consolidate *kernel_text_address() functions
The functionality between kernel_text_address() and _kernel_text_address()
is the same except that _kernel_text_address() does a little more (that
function needs a rename, but that can be done another time). Instead of
having duplicate code in both, simply have _kernel_text_address() calls
kernel_text_address() instead.
This is marked for stable because there's an RCU bug that can happen if
one of these functions gets called while RCU is not watching. That fix
depends on this fix to keep from having to write the fix twice.
Cc: stable@vger.kernel.org
Fixes:
0be964be0 ("module: Sanitize RCU usage and locking")
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Paul E. McKenney [Fri, 22 Sep 2017 21:10:22 +0000 (14:10 -0700)]
rcu: Allow for page faults in NMI handlers
A number of architecture invoke rcu_irq_enter() on exception entry in
order to allow RCU read-side critical sections in the exception handler
when the exception is from an idle or nohz_full CPU. This works, at
least unless the exception happens in an NMI handler. In that case,
rcu_nmi_enter() would already have exited the extended quiescent state,
which would mean that rcu_irq_enter() would (incorrectly) cause RCU
to think that it is again in an extended quiescent state. This will
in turn result in lockdep splats in response to later RCU read-side
critical sections.
This commit therefore causes rcu_irq_enter() and rcu_irq_exit() to
take no action if there is an rcu_nmi_enter() in effect, thus avoiding
the unscheduled return to RCU quiescent state. This in turn should
make the kernel safe for on-demand RCU voyeurism.
Link: http://lkml.kernel.org/r/20170922211022.GA18084@linux.vnet.ibm.com
Cc: stable@vger.kernel.org
Fixes:
0be964be0 ("module: Sanitize RCU usage and locking")
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Tahsin Erdogan [Sun, 17 Sep 2017 10:23:48 +0000 (03:23 -0700)]
tracing: Fix trace_pipe behavior for instance traces
When reading data from trace_pipe, tracing_wait_pipe() performs a
check to see if tracing has been turned off after some data was read.
Currently, this check always looks at global trace state, but it
should be checking the trace instance where trace_pipe is located at.
Because of this bug, cat instances/i1/trace_pipe in the following
script will immediately exit instead of waiting for data:
cd /sys/kernel/debug/tracing
echo 0 > tracing_on
mkdir -p instances/i1
echo 1 > instances/i1/tracing_on
echo 1 > instances/i1/events/sched/sched_process_exec/enable
cat instances/i1/trace_pipe
Link: http://lkml.kernel.org/r/20170917102348.1615-1-tahsin@google.com
Cc: stable@vger.kernel.org
Fixes:
10246fa35d4f ("tracing: give easy way to clear trace buffer")
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Ziqian SUN (Zamir) [Mon, 11 Sep 2017 06:26:35 +0000 (14:26 +0800)]
tracing: Ignore mmiotrace from kernel commandline
The mmiotrace tracer cannot be enabled with ftrace=mmiotrace in kernel
commandline. With this patch, noboot is added to the tracer struct,
and when system boot with a tracer that has noboot=true, it will print
out a warning message and continue booting.
Link: http://lkml.kernel.org/r/1505111195-31942-1-git-send-email-zsun@redhat.com
Signed-off-by: Ziqian SUN (Zamir) <zsun@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Bo Yan [Mon, 18 Sep 2017 17:03:35 +0000 (10:03 -0700)]
tracing: Erase irqsoff trace with empty write
One convenient way to erase trace is "echo > trace". However, this
is currently broken if the current tracer is irqsoff tracer. This
is because irqsoff tracer use max_buffer as the default trace
buffer.
Set the max_buffer as the one to be cleared when it's the trace
buffer currently in use.
Link: http://lkml.kernel.org/r/1505754215-29411-1-git-send-email-byan@nvidia.com
Cc: <mingo@redhat.com>
Cc: stable@vger.kernel.org
Fixes:
4acd4d00f ("tracing: give easy way to clear trace buffer")
Signed-off-by: Bo Yan <byan@nvidia.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Baohong Liu [Tue, 5 Sep 2017 21:57:19 +0000 (16:57 -0500)]
tracing: Apply trace_clock changes to instance max buffer
Currently trace_clock timestamps are applied to both regular and max
buffers only for global trace. For instance trace, trace_clock
timestamps are applied only to regular buffer. But, regular and max
buffers can be swapped, for example, following a snapshot. So, for
instance trace, bad timestamps can be seen following a snapshot.
Let's apply trace_clock timestamps to instance max buffer as well.
Link: http://lkml.kernel.org/r/ebdb168d0be042dcdf51f81e696b17fabe3609c1.1504642143.git.tom.zanussi@linux.intel.com
Cc: stable@vger.kernel.org
Fixes:
277ba0446 ("tracing: Add interface to allow multiple trace buffers")
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Chunyu Hu [Tue, 5 Sep 2017 05:36:46 +0000 (13:36 +0800)]
tracing: Fix clear of RECORDED_TGID flag when disabling trace event
When disabling one trace event, the RECORDED_TGID flag in the event
file is not correctly cleared. It's clearing RECORDED_CMD flag when
it should clear RECORDED_TGID flag.
Link: http://lkml.kernel.org/r/1504589806-8425-1-git-send-email-chuhu@redhat.com
Cc: Joel Fernandes <joelaf@google.com>
Cc: stable@vger.kernel.org
Fixes:
d914ba37d7 ("tracing: Add support for recording tgid of tasks")
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Steven Rostedt (VMware) [Tue, 5 Sep 2017 15:32:01 +0000 (11:32 -0400)]
tracing: Add barrier to trace_printk() buffer nesting modification
trace_printk() uses 4 buffers, one for each context (normal, softirq, irq
and NMI), such that it does not need to worry about one context preempting
the other. There's a nesting counter that gets incremented to figure out
which buffer to use. If the context gets preempted by another context which
calls trace_printk() it will increment the counter and use the next buffer,
and restore the counter when it is finished.
The problem is that gcc may optimize the modification of the buffer nesting
counter and it may not be incremented in memory before the buffer is used.
If this happens, and the context gets interrupted by another context, it
could pick the same buffer and corrupt the one that is being used.
Compiler barriers need to be added after the nesting variable is incremented
and before it is decremented to prevent usage of the context buffers by more
than one context at the same time.
Cc: Andy Lutomirski <luto@kernel.org>
Cc: stable@vger.kernel.org
Fixes:
e2ace00117 ("tracing: Choose static tp_printk buffer by explicit nesting count")
Hat-tip-to: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Steven Rostedt (VMware) [Fri, 1 Sep 2017 16:18:28 +0000 (12:18 -0400)]
ftrace: Fix memleak when unregistering dynamic ops when tracing disabled
If function tracing is disabled by the user via the function-trace option or
the proc sysctl file, and a ftrace_ops that was allocated on the heap is
unregistered, then the shutdown code exits out without doing the proper
clean up. This was found via kmemleak and running the ftrace selftests, as
one of the tests unregisters with function tracing disabled.
# cat kmemleak
unreferenced object 0xffffffffa0020000 (size 4096):
comm "swapper/0", pid 1, jiffies
4294668889 (age 569.209s)
hex dump (first 32 bytes):
55 ff 74 24 10 55 48 89 e5 ff 74 24 18 55 48 89 U.t$.UH...t$.UH.
e5 48 81 ec a8 00 00 00 48 89 44 24 50 48 89 4c .H......H.D$PH.L
backtrace:
[<
ffffffff81d64665>] kmemleak_vmalloc+0x85/0xf0
[<
ffffffff81355631>] __vmalloc_node_range+0x281/0x3e0
[<
ffffffff8109697f>] module_alloc+0x4f/0x90
[<
ffffffff81091170>] arch_ftrace_update_trampoline+0x160/0x420
[<
ffffffff81249947>] ftrace_startup+0xe7/0x300
[<
ffffffff81249bd2>] register_ftrace_function+0x72/0x90
[<
ffffffff81263786>] trace_selftest_ops+0x204/0x397
[<
ffffffff82bb8971>] trace_selftest_startup_function+0x394/0x624
[<
ffffffff81263a75>] run_tracer_selftest+0x15c/0x1d7
[<
ffffffff82bb83f1>] init_trace_selftests+0x75/0x192
[<
ffffffff81002230>] do_one_initcall+0x90/0x1e2
[<
ffffffff82b7d620>] kernel_init_freeable+0x350/0x3fe
[<
ffffffff81d61ec3>] kernel_init+0x13/0x122
[<
ffffffff81d72c6a>] ret_from_fork+0x2a/0x40
[<
ffffffffffffffff>] 0xffffffffffffffff
Cc: stable@vger.kernel.org
Fixes:
12cce594fa ("ftrace/x86: Allow !CONFIG_PREEMPT dynamic ops to use allocated trampolines")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Steven Rostedt (VMware) [Fri, 1 Sep 2017 16:04:09 +0000 (12:04 -0400)]
ftrace: Fix selftest goto location on error
In the second iteration of trace_selftest_ops(), the error goto label is
wrong in the case where trace_selftest_test_global_cnt is off. In the
case of error, it leaks the dynamic ops that was allocated.
Cc: stable@vger.kernel.org
Fixes:
95950c2e ("ftrace: Add self-tests for multiple function trace users")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Steven Rostedt (VMware) [Thu, 31 Aug 2017 21:36:51 +0000 (17:36 -0400)]
ftrace: Zero out ftrace hashes when a module is removed
When a ftrace filter has a module function, and that module is removed, the
filter still has its address as being enabled. This can cause interesting
side effects. Nothing dangerous, but unwanted functions can be traced
because of it.
# cd /sys/kernel/tracing
# echo ':mod:snd_seq' > set_ftrace_filter
# cat set_ftrace_filter
snd_use_lock_sync_helper [snd_seq]
check_event_type_and_length [snd_seq]
snd_seq_ioctl_pversion [snd_seq]
snd_seq_ioctl_client_id [snd_seq]
snd_seq_ioctl_get_queue_tempo [snd_seq]
update_timestamp_of_queue [snd_seq]
snd_seq_ioctl_get_queue_status [snd_seq]
snd_seq_set_queue_tempo [snd_seq]
snd_seq_ioctl_set_queue_tempo [snd_seq]
snd_seq_ioctl_get_queue_timer [snd_seq]
seq_free_client1 [snd_seq]
[..]
# rmmod snd_seq
# cat set_ftrace_filter
# modprobe kvm
# cat set_ftrace_filter
kvm_set_cr4 [kvm]
kvm_emulate_hypercall [kvm]
kvm_set_dr [kvm]
This is because removing the snd_seq module after it was being filtered,
left the address of the snd_seq functions in the hash. When the kvm module
was loaded, some of its functions were loaded at the same address as the
snd_seq module. This would enable them to be filtered and traced.
Now we don't want to clear the hash completely. That would cause removing a
module where only its functions are filtered, to cause the tracing to enable
all functions, as an empty filter means to trace all functions. Instead,
just set the hash ip address to zero. Then it will never match any function.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Steven Rostedt (VMware) [Thu, 31 Aug 2017 21:03:47 +0000 (17:03 -0400)]
tracing: Only have rmmod clear buffers that its events were active in
Currently, when a module event is enabled, when that module is removed, it
clears all ring buffers. This is to prevent another module from being loaded
and having one of its trace event IDs from reusing a trace event ID of the
removed module. This could cause undesirable effects as the trace event of
the new module would be using its own processing algorithms to process raw
data of another event. To prevent this, when a module is loaded, if any of
its events have been used (signified by the WAS_ENABLED event call flag,
which is never cleared), all ring buffers are cleared, just in case any one
of them contains event data of the removed event.
The problem is, there's no reason to clear all ring buffers if only one (or
less than all of them) uses one of the events. Instead, only clear the ring
buffers that recorded the events of a module that is being removed.
To do this, instead of keeping the WAS_ENABLED flag with the trace event
call, move it to the per instance (per ring buffer) event file descriptor.
The event file descriptor maps each event to a separate ring buffer
instance. Then when the module is removed, only the ring buffers that
activated one of the module's events get cleared. The rest are not touched.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Zev Weiss [Wed, 30 Aug 2017 10:36:38 +0000 (05:36 -0500)]
ftrace: Fix debug preempt config name in stack_tracer_{en,dis}able
stack_tracer_disable()/stack_tracer_enable() had been using the wrong
name for the config symbol to enable their preempt-debugging checks --
fix with a word swap.
Link: http://lkml.kernel.org/r/20170831154036.4xldyakmmhuts5x7@hatter.bewilderbeest.net
Cc: stable@vger.kernel.org
Fixes:
8aaf1ee70e ("tracing: Rename trace_active to disable_stack_tracer and inline its modification")
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Linus Torvalds [Mon, 28 Aug 2017 00:20:40 +0000 (17:20 -0700)]
Linux 4.13-rc7
Linus Torvalds [Mon, 28 Aug 2017 00:10:34 +0000 (17:10 -0700)]
Merge tag 'iommu-fixes-v4.13-rc6' of git://git./linux/kernel/git/joro/iommu
Pull IOMMU fix from Joerg Roedel:
"Another fix, this time in common IOMMU sysfs code.
In the conversion from the old iommu sysfs-code to the
iommu_device_register interface, I missed to update the release path
for the struct device associated with an IOMMU. It freed the 'struct
device', which was a pointer before, but is now embedded in another
struct.
Freeing from the middle of allocated memory had all kinds of nasty
side effects when an IOMMU was unplugged. Unfortunatly nobody
unplugged and IOMMU until now, so this was not discovered earlier. The
fix is to make the 'struct device' a pointer again"
* tag 'iommu-fixes-v4.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu: Fix wrong freeing of iommu_device->dev
Linus Torvalds [Mon, 28 Aug 2017 00:08:37 +0000 (17:08 -0700)]
Merge tag 'char-misc-4.13-rc7' of git://git./linux/kernel/git/gregkh/char-misc
Pull char/misc fix from Greg KH:
"Here is a single misc driver fix for 4.13-rc7. It resolves a reported
problem in the Android binder driver due to previous patches in
4.13-rc.
It's been in linux-next with no reported issues"
* tag 'char-misc-4.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
ANDROID: binder: fix proc->tsk check.
Linus Torvalds [Mon, 28 Aug 2017 00:03:33 +0000 (17:03 -0700)]
Merge tag 'staging-4.13-rc7' of git://git./linux/kernel/git/gregkh/staging
Pull staging/iio fixes from Greg KH:
"Here are few small staging driver fixes, and some more IIO driver
fixes for 4.13-rc7. Nothing major, just resolutions for some reported
problems.
All of these have been in linux-next with no reported problems"
* tag 'staging-4.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
iio: magnetometer: st_magn: remove ihl property for LSM303AGR
iio: magnetometer: st_magn: fix status register address for LSM303AGR
iio: hid-sensor-trigger: Fix the race with user space powering up sensors
iio: trigger: stm32-timer: fix get trigger mode
iio: imu: adis16480: Fix acceleration scale factor for adis16480
PATCH] iio: Fix some documentation warnings
staging: rtl8188eu: add RNX-N150NUB support
Revert "staging: fsl-mc: be consistent when checking strcmp() return"
iio: adc: stm32: fix common clock rate
iio: adc: ina219: Avoid underflow for sleeping time
iio: trigger: stm32-timer: add enable attribute
iio: trigger: stm32-timer: fix get/set down count direction
iio: trigger: stm32-timer: fix write_raw return value
iio: trigger: stm32-timer: fix quadrature mode get routine
iio: bmp280: properly initialize device for humidity reading
Linus Torvalds [Mon, 28 Aug 2017 00:01:54 +0000 (17:01 -0700)]
Merge tag 'ntb-4.13-bugfixes' of git://github.com/jonmason/ntb
Pull NTB fixes from Jon Mason:
"NTB bug fixes to address an incorrect ntb_mw_count reference in the
NTB transport, improperly bringing down the link if SPADs are
corrupted, and an out-of-order issue regarding link negotiation and
data passing"
* tag 'ntb-4.13-bugfixes' of git://github.com/jonmason/ntb:
ntb: ntb_test: ensure the link is up before trying to configure the mws
ntb: transport shouldn't disable link due to bogus values in SPADs
ntb: use correct mw_count function in ntb_tool and ntb_transport
Linus Torvalds [Sun, 27 Aug 2017 23:25:09 +0000 (16:25 -0700)]
Avoid page waitqueue race leaving possible page locker waiting
The "lock_page_killable()" function waits for exclusive access to the
page lock bit using the WQ_FLAG_EXCLUSIVE bit in the waitqueue entry
set.
That means that if it gets woken up, other waiters may have been
skipped.
That, in turn, means that if it sees the page being unlocked, it *must*
take that lock and return success, even if a lethal signal is also
pending.
So instead of checking for lethal signals first, we need to check for
them after we've checked the actual bit that we were waiting for. Even
if that might then delay the killing of the process.
This matches the order of the old "wait_on_bit_lock()" infrastructure
that the page locking used to use (and is still used in a few other
areas).
Note that if we still return an error after having unsuccessfully tried
to acquire the page lock, that is ok: that means that some other thread
was able to get ahead of us and lock the page, and when that other
thread then unlocks the page, the wakeup event will be repeated. So any
other pending waiters will now get properly woken up.
Fixes:
62906027091f ("mm: add PageWaiters indicating tasks are waiting for a page bit")
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Jan Kara <jack@suse.cz>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Sun, 27 Aug 2017 20:55:12 +0000 (13:55 -0700)]
Minor page waitqueue cleanups
Tim Chen and Kan Liang have been battling a customer load that shows
extremely long page wakeup lists. The cause seems to be constant NUMA
migration of a hot page that is shared across a lot of threads, but the
actual root cause for the exact behavior has not been found.
Tim has a patch that batches the wait list traversal at wakeup time, so
that we at least don't get long uninterruptible cases where we traverse
and wake up thousands of processes and get nasty latency spikes. That
is likely 4.14 material, but we're still discussing the page waitqueue
specific parts of it.
In the meantime, I've tried to look at making the page wait queues less
expensive, and failing miserably. If you have thousands of threads
waiting for the same page, it will be painful. We'll need to try to
figure out the NUMA balancing issue some day, in addition to avoiding
the excessive spinlock hold times.
That said, having tried to rewrite the page wait queues, I can at least
fix up some of the braindamage in the current situation. In particular:
(a) we don't want to continue walking the page wait list if the bit
we're waiting for already got set again (which seems to be one of
the patterns of the bad load). That makes no progress and just
causes pointless cache pollution chasing the pointers.
(b) we don't want to put the non-locking waiters always on the front of
the queue, and the locking waiters always on the back. Not only is
that unfair, it means that we wake up thousands of reading threads
that will just end up being blocked by the writer later anyway.
Also add a comment about the layout of 'struct wait_page_key' - there is
an external user of it in the cachefiles code that means that it has to
match the layout of 'struct wait_bit_key' in the two first members. It
so happens to match, because 'struct page *' and 'unsigned long *' end
up having the same values simply because the page flags are the first
member in struct page.
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Christopher Lameter <cl@linux.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Sun, 27 Aug 2017 19:12:25 +0000 (12:12 -0700)]
Clarify (and fix) MAX_LFS_FILESIZE macros
We have a MAX_LFS_FILESIZE macro that is meant to be filled in by
filesystems (and other IO targets) that know they are 64-bit clean and
don't have any 32-bit limits in their IO path.
It turns out that our 32-bit value for that limit was bogus. On 32-bit,
the VM layer is limited by the page cache to only 32-bit index values,
but our logic for that was confusing and actually wrong. We used to
define that value to
(((loff_t)PAGE_SIZE << (BITS_PER_LONG-1))-1)
which is actually odd in several ways: it limits the index to 31 bits,
and then it limits files so that they can't have data in that last byte
of a page that has the highest 31-bit index (ie page index 0x7fffffff).
Neither of those limitations make sense. The index is actually the full
32 bit unsigned value, and we can use that whole full page. So the
maximum size of the file would logically be "PAGE_SIZE << BITS_PER_LONG".
However, we do wan tto avoid the maximum index, because we have code
that iterates over the page indexes, and we don't want that code to
overflow. So the maximum size of a file on a 32-bit host should
actually be one page less than the full 32-bit index.
So the actual limit is ULONG_MAX << PAGE_SHIFT. That means that we will
not actually be using the page of that last index (ULONG_MAX), but we
can grow a file up to that limit.
The wrong value of MAX_LFS_FILESIZE actually caused problems for Doug
Nazar, who was still using a 32-bit host, but with a 9.7TB 2 x RAID5
volume. It turns out that our old MAX_LFS_FILESIZE was 8TiB (well, one
byte less), but the actual true VM limit is one page less than 16TiB.
This was invisible until commit
c2a9737f45e2 ("vfs,mm: fix a dead loop
in truncate_inode_pages_range()"), which started applying that
MAX_LFS_FILESIZE limit to block devices too.
NOTE! On 64-bit, the page index isn't a limiter at all, and the limit is
actually just the offset type itself (loff_t), which is signed. But for
clarity, on 64-bit, just use the maximum signed value, and don't make
people have to count the number of 'f' characters in the hex constant.
So just use LLONG_MAX for the 64-bit case. That was what the value had
been before too, just written out as a hex constant.
Fixes:
c2a9737f45e2 ("vfs,mm: fix a dead loop in truncate_inode_pages_range()")
Reported-and-tested-by: Doug Nazar <nazard@nazar.ca>
Cc: Andreas Dilger <adilger@dilger.ca>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Sat, 26 Aug 2017 19:48:29 +0000 (12:48 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/dtor/input
Pull input fixes from Dmitry Torokhov:
- a tweak to the IBM Trackpoint driver that helps recognizing
trackpoints on never Lenovo Carbons
- a fix to the ALPS driver solving scroll issues on some Dells
- yet another ACPI ID has been added to Elan I2C toucpad driver
- quieted diagnostic message in soc_button_array driver
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: ALPS - fix two-finger scroll breakage in right side on ALPS touchpad
Input: soc_button_array - silence -ENOENT error on Dell XPS13 9365
Input: trackpoint - add new trackpoint firmware ID
Input: elan_i2c - add ELAN0602 ACPI ID to support Lenovo Yoga310
Linus Torvalds [Sat, 26 Aug 2017 19:46:14 +0000 (12:46 -0700)]
Merge tag 'pci-v4.13-fixes-3' of git://git./linux/kernel/git/helgaas/pci
Pull PCI fix from Bjorn Helgaas:
"Remove needlessly alarming MSI affinity warning (this is not actually
a bug fix, but the warning prompts unnecessary bug reports)"
* tag 'pci-v4.13-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI/MSI: Don't warn when irq_create_affinity_masks() returns NULL
Linus Torvalds [Sat, 26 Aug 2017 16:06:28 +0000 (09:06 -0700)]
Merge branch 'x86-urgent-for-linus' of git://git./linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
"Two fixes: one for an ldt_struct handling bug and a cherry-picked
objtool fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Fix use-after-free of ldt_struct
objtool: Fix '-mtune=atom' decoding support in objtool 2.0
Linus Torvalds [Sat, 26 Aug 2017 16:02:18 +0000 (09:02 -0700)]
Merge branch 'timers-urgent-for-linus' of git://git./linux/kernel/git/tip/tip
Pull timer fix from Ingo Molnar:
"Fix a timer granularity handling race+bug, which would manifest itself
by spuriously increasing timeouts of some timers (from 1 jiffy to ~500
jiffies in the worst case measured) in certain nohz states"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timers: Fix excessive granularity of new timers after a nohz idle
Linus Torvalds [Sat, 26 Aug 2017 15:59:50 +0000 (08:59 -0700)]
Merge branch 'perf-urgent-for-linus' of git://git./linux/kernel/git/tip/tip
Pull perf fix from Ingo Molnar:
"A single fix to not allow nonsensical event groups that result in
kernel warnings"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix group {cpu,task} validation
Linus Torvalds [Sat, 26 Aug 2017 01:02:27 +0000 (18:02 -0700)]
Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
"6 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/memblock.c: reversed logic in memblock_discard()
fork: fix incorrect fput of ->exe_file causing use-after-free
mm/madvise.c: fix freeing of locked page with MADV_FREE
dax: fix deadlock due to misaligned PMD faults
mm, shmem: fix handling /sys/kernel/mm/transparent_hugepage/shmem_enabled
PM/hibernate: touch NMI watchdog when creating snapshot
Linus Torvalds [Sat, 26 Aug 2017 00:46:23 +0000 (17:46 -0700)]
Merge tag 'for-linus' of git://git./virt/kvm/kvm
Pull Paolo Bonzini:
"Bugfixes for x86, PPC and s390"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: PPC: Book3S: Fix race and leak in kvm_vm_ioctl_create_spapr_tce()
KVM, pkeys: do not use PKRU value in vcpu->arch.guest_fpu.state
KVM: x86: simplify handling of PKRU
KVM: x86: block guest protection keys unless the host has them enabled
KVM: PPC: Book3S HV: Add missing barriers to XIVE code and document them
KVM: PPC: Book3S HV: Workaround POWER9 DD1.0 bug causing IPB bit loss
KVM: PPC: Book3S HV: Use msgsync with hypervisor doorbells on POWER9
KVM: s390: sthyi: fix specification exception detection
KVM: s390: sthyi: fix sthyi inline assembly
Linus Torvalds [Sat, 26 Aug 2017 00:40:03 +0000 (17:40 -0700)]
Merge tag 'for_linus' of git://git./linux/kernel/git/mst/vhost
Pull virtio fixes from Michael Tsirkin:
"Fixes two obvious bugs in virtio pci"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio_pci: fix cpu affinity support
virtio_blk: fix incorrect message when disk is resized
Linus Torvalds [Sat, 26 Aug 2017 00:32:35 +0000 (17:32 -0700)]
Merge tag 'powerpc-4.13-8' of git://git./linux/kernel/git/powerpc/linux
Pull powerpc fix from Michael Ellerman:
"Just one fix, to add a barrier in the switch_mm() code to make sure
the mm cpumask update is ordered vs the MMU starting to load
translations. As far as we know no one's actually hit the bug, but
that's just luck.
Thanks to Benjamin Herrenschmidt, Nicholas Piggin"
* tag 'powerpc-4.13-8' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/mm: Ensure cpumask update is ordered
Linus Torvalds [Sat, 26 Aug 2017 00:27:26 +0000 (17:27 -0700)]
Merge tag 'nfsd-4.13-2' of git://linux-nfs.org/~bfields/linux
Pull nfsd fixes from Bruce Fields:
"Two nfsd bugfixes, neither 4.13 regressions, but both potentially
serious"
* tag 'nfsd-4.13-2' of git://linux-nfs.org/~bfields/linux:
net: sunrpc: svcsock: fix NULL-pointer exception
nfsd: Limit end of page list when decoding NFSv4 WRITE
Linus Torvalds [Sat, 26 Aug 2017 00:22:33 +0000 (17:22 -0700)]
Merge tag 'cifs-fixes-for-4.13-rc6-and-stable' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Some bug fixes for stable for cifs"
* tag 'cifs-fixes-for-4.13-rc6-and-stable' of git://git.samba.org/sfrench/cifs-2.6:
cifs: return ENAMETOOLONG for overlong names in cifs_open()/cifs_lookup()
cifs: Fix df output for users with quota limits
Linus Torvalds [Sat, 26 Aug 2017 00:09:19 +0000 (17:09 -0700)]
Merge tag 'for-linus-
20170825' of git://git.infradead.org/linux-mtd
Pull MTD fixes from Brian Norris:
"Two fixes - one for a 4.13 regression, and the other for an older one:
- Atmel NAND: since we started utilizing ONFI timings, we found that
we were being too restrict at rejecting them, partly due to
discrepancies in ONFI 4.0 and earlier versions. Relax the
restriction to keep these platforms booting. This is a 4.13-rc1
regression.
- nandsim: repeated probe/removal may not work after a failed init,
because we didn't free up our debugfs files properly on the failure
path. This has been around since 3.8, but it's nice to get this
fixed now in a nice easy patch that can target -stable, since
there's already refactoring work (that also fixes the issue)
targeted for the next merge window"
* tag 'for-linus-
20170825' of git://git.infradead.org/linux-mtd:
mtd: nand: atmel: Relax tADL_min constraint
mtd: nandsim: remove debugfs entries in error path
Linus Torvalds [Sat, 26 Aug 2017 00:02:59 +0000 (17:02 -0700)]
Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"A small batch of fixes that should be included for the 4.13 release.
This contains:
- Revert of the 4k loop blocksize support. Even with a recent batch
of 4 fixes, we're still not really happy with it. Rather than be
stuck with an API issue, let's revert it and get it right for 4.14.
- Trivial patch from Bart, adding a few flags to the blk-mq debugfs
exports that were added in this release, but not to the debugfs
parts.
- Regression fix for bsg, fixing a potential kernel panic. From
Benjamin.
- Tweak for the blk throttling, improving how we account discards.
From Shaohua"
* 'for-linus' of git://git.kernel.dk/linux-block:
blk-mq-debugfs: Add names for recently added flags
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer
Revert "loop: support 4k physical blocksize"
blk-throttle: cap discard request size
Linus Torvalds [Fri, 25 Aug 2017 23:59:38 +0000 (16:59 -0700)]
Merge branch 'i2c/for-current' of git://git./linux/kernel/git/wsa/linux
Pull i2c fixes from Wolfram Sang:
"I2C has some bugfixes for you: mainly Jarkko fixed up a few things in
the designware driver regarding the new slave mode. But Ulf also fixed
a long-standing and now agreed suspend problem. Plus, some simple
stuff which nonetheless needs fixing"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: designware: Fix runtime PM for I2C slave mode
i2c: designware: Remove needless pm_runtime_put_noidle() call
i2c: aspeed: fixed potential null pointer dereference
i2c: simtec: use release_mem_region instead of release_resource
i2c: core: Make comment about I2C table requirement to reflect the code
i2c: designware: Fix standard mode speed when configuring the slave mode
i2c: designware: Fix oops from i2c_dw_irq_handler_slave
i2c: designware: Fix system suspend
Christoph Hellwig [Fri, 25 Aug 2017 23:58:42 +0000 (18:58 -0500)]
PCI/MSI: Don't warn when irq_create_affinity_masks() returns NULL
irq_create_affinity_masks() can return NULL on non-SMP systems, when there
are not enough "free" vectors available to spread, or if memory allocation
for the CPU masks fails. Only the allocation failure is of interest, and
even then the system will work just fine except for non-optimally spread
vectors. Thus remove the warnings.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: David S. Miller <davem@davemloft.net>
Linus Torvalds [Fri, 25 Aug 2017 23:57:53 +0000 (16:57 -0700)]
Merge tag 'mmc-v4.13-rc6' of git://git./linux/kernel/git/ulfh/mmc
Pull MMC fix from Ulf Hansson:
"MMC core: don't return error code R1_OUT_OF_RANGE for open-ending mode"
* tag 'mmc-v4.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
mmc: block: prevent propagating R1_OUT_OF_RANGE for open-ending mode
Linus Torvalds [Fri, 25 Aug 2017 23:56:04 +0000 (16:56 -0700)]
Merge tag 'sound-4.13-rc7' of git://git./linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"We're keeping in a good shape, this batch contains just a few small
fixes (a regression fix for ASoC rt5677 codec, NULL dereference and
error-path fixes in firewire, and a corner-case ioctl error fix for
user TLV), as well as usual quirks for USB-audio and HD-audio"
* tag 'sound-4.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ASoC: rt5677: Reintroduce I2C device IDs
ALSA: hda - Add stereo mic quirk for Lenovo G50-70 (17aa:3978)
ALSA: core: Fix unexpected error at replacing user TLV
ALSA: usb-audio: Add delay quirk for H650e/Jabra 550a USB headsets
ALSA: firewire-motu: destroy stream data surely at failure of card initialization
ALSA: firewire: fix NULL pointer dereference when releasing uninitialized data of iso-resource
Linus Torvalds [Fri, 25 Aug 2017 23:43:08 +0000 (16:43 -0700)]
Merge tag 'dmaengine-fix-4.13-rc7' of git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine fix from Vinod Koul:
"A single fix for tegra210-adma driver to check of_irq_get() error"
* tag 'dmaengine-fix-4.13-rc7' of git://git.infradead.org/users/vkoul/slave-dma:
dmaengine: tegra210-adma: fix of_irq_get() error check
Linus Torvalds [Fri, 25 Aug 2017 23:39:51 +0000 (16:39 -0700)]
Merge tag 'drm-fixes-for-v4.13-rc7' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"Fixes for rc7, nothing too crazy, some core, i915, and sunxi fixes,
Intel CI has been responsible for some of these fixes being required"
* tag 'drm-fixes-for-v4.13-rc7' of git://people.freedesktop.org/~airlied/linux:
drm/i915/gvt: Fix the kernel null pointer error
drm: Release driver tracking before making the object available again
drm/i915: Clear lost context-switch interrupts across reset
drm/i915/bxt: use NULL for GPIO connection ID
drm/i915/cnl: Fix LSPCON support.
drm/i915/vbt: ignore extraneous child devices for a port
drm/i915: Initialize 'data' in intel_dsi_dcs_backlight.c
drm/atomic: If the atomic check fails, return its value first
drm/atomic: Handle -EDEADLK with out-fences correctly
drm: Fix framebuffer leak
drm/imx: ipuv3-plane: fix YUV framebuffer scanout on the base plane
gpu: ipu-v3: add DRM dependency
drm/rockchip: Fix suspend crash when drm is not bound
drm/sun4i: Implement drm_driver lastclose to restore fbdev console
Pavel Tatashin [Fri, 25 Aug 2017 22:55:46 +0000 (15:55 -0700)]
mm/memblock.c: reversed logic in memblock_discard()
In recently introduced memblock_discard() there is a reversed logic bug.
Memory is freed of static array instead of dynamically allocated one.
Link: http://lkml.kernel.org/r/1503511441-95478-2-git-send-email-pasha.tatashin@oracle.com
Fixes:
3010f876500f ("mm: discard memblock data later")
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reported-by: Woody Suwalski <terraluna977@gmail.com>
Tested-by: Woody Suwalski <terraluna977@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Eric Biggers [Fri, 25 Aug 2017 22:55:43 +0000 (15:55 -0700)]
fork: fix incorrect fput of ->exe_file causing use-after-free
Commit
7c051267931a ("mm, fork: make dup_mmap wait for mmap_sem for
write killable") made it possible to kill a forking task while it is
waiting to acquire its ->mmap_sem for write, in dup_mmap().
However, it was overlooked that this introduced an new error path before
a reference is taken on the mm_struct's ->exe_file. Since the
->exe_file of the new mm_struct was already set to the old ->exe_file by
the memcpy() in dup_mm(), it was possible for the mmput() in the error
path of dup_mm() to drop a reference to ->exe_file which was never
taken.
This caused the struct file to later be freed prematurely.
Fix it by updating mm_init() to NULL out the ->exe_file, in the same
place it clears other things like the list of mmaps.
This bug was found by syzkaller. It can be reproduced using the
following C program:
#define _GNU_SOURCE
#include <pthread.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <sys/syscall.h>
#include <sys/wait.h>
#include <unistd.h>
static void *mmap_thread(void *_arg)
{
for (;;) {
mmap(NULL, 0x1000000, PROT_READ,
MAP_POPULATE|MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
}
}
static void *fork_thread(void *_arg)
{
usleep(rand() % 10000);
fork();
}
int main(void)
{
fork();
fork();
fork();
for (;;) {
if (fork() == 0) {
pthread_t t;
pthread_create(&t, NULL, mmap_thread, NULL);
pthread_create(&t, NULL, fork_thread, NULL);
usleep(rand() % 10000);
syscall(__NR_exit_group, 0);
}
wait(NULL);
}
}
No special kernel config options are needed. It usually causes a NULL
pointer dereference in __remove_shared_vm_struct() during exit, or in
dup_mmap() (which is usually inlined into copy_process()) during fork.
Both are due to a vm_area_struct's ->vm_file being used after it's
already been freed.
Google Bug Id:
64772007
Link: http://lkml.kernel.org/r/20170823211408.31198-1-ebiggers3@gmail.com
Fixes:
7c051267931a ("mm, fork: make dup_mmap wait for mmap_sem for write killable")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org> [v4.7+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Eric Biggers [Fri, 25 Aug 2017 22:55:39 +0000 (15:55 -0700)]
mm/madvise.c: fix freeing of locked page with MADV_FREE
If madvise(..., MADV_FREE) split a transparent hugepage, it called
put_page() before unlock_page().
This was wrong because put_page() can free the page, e.g. if a
concurrent madvise(..., MADV_DONTNEED) has removed it from the memory
mapping. put_page() then rightfully complained about freeing a locked
page.
Fix this by moving the unlock_page() before put_page().
This bug was found by syzkaller, which encountered the following splat:
BUG: Bad page state in process syzkaller412798 pfn:1bd800
page:
ffffea0006f60000 count:0 mapcount:0 mapping: (null) index:0x20a00
flags: 0x200000000040019(locked|uptodate|dirty|swapbacked)
raw:
0200000000040019 0000000000000000 0000000000020a00 00000000ffffffff
raw:
ffffea0006f60020 ffffea0006f60020 0000000000000000 0000000000000000
page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
bad because of flags: 0x1(locked)
Modules linked in:
CPU: 1 PID: 3037 Comm: syzkaller412798 Not tainted 4.13.0-rc5+ #35
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:16 [inline]
dump_stack+0x194/0x257 lib/dump_stack.c:52
bad_page+0x230/0x2b0 mm/page_alloc.c:565
free_pages_check_bad+0x1f0/0x2e0 mm/page_alloc.c:943
free_pages_check mm/page_alloc.c:952 [inline]
free_pages_prepare mm/page_alloc.c:1043 [inline]
free_pcp_prepare mm/page_alloc.c:1068 [inline]
free_hot_cold_page+0x8cf/0x12b0 mm/page_alloc.c:2584
__put_single_page mm/swap.c:79 [inline]
__put_page+0xfb/0x160 mm/swap.c:113
put_page include/linux/mm.h:814 [inline]
madvise_free_pte_range+0x137a/0x1ec0 mm/madvise.c:371
walk_pmd_range mm/pagewalk.c:50 [inline]
walk_pud_range mm/pagewalk.c:108 [inline]
walk_p4d_range mm/pagewalk.c:134 [inline]
walk_pgd_range mm/pagewalk.c:160 [inline]
__walk_page_range+0xc3a/0x1450 mm/pagewalk.c:249
walk_page_range+0x200/0x470 mm/pagewalk.c:326
madvise_free_page_range.isra.9+0x17d/0x230 mm/madvise.c:444
madvise_free_single_vma+0x353/0x580 mm/madvise.c:471
madvise_dontneed_free mm/madvise.c:555 [inline]
madvise_vma mm/madvise.c:664 [inline]
SYSC_madvise mm/madvise.c:832 [inline]
SyS_madvise+0x7d3/0x13c0 mm/madvise.c:760
entry_SYSCALL_64_fastpath+0x1f/0xbe
Here is a C reproducer:
#define _GNU_SOURCE
#include <pthread.h>
#include <sys/mman.h>
#include <unistd.h>
#define MADV_FREE 8
#define PAGE_SIZE 4096
static void *mapping;
static const size_t mapping_size = 0x1000000;
static void *madvise_thrproc(void *arg)
{
madvise(mapping, mapping_size, (long)arg);
}
int main(void)
{
pthread_t t[2];
for (;;) {
mapping = mmap(NULL, mapping_size, PROT_WRITE,
MAP_POPULATE|MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
munmap(mapping + mapping_size / 2, PAGE_SIZE);
pthread_create(&t[0], 0, madvise_thrproc, (void*)MADV_DONTNEED);
pthread_create(&t[1], 0, madvise_thrproc, (void*)MADV_FREE);
pthread_join(t[0], NULL);
pthread_join(t[1], NULL);
munmap(mapping, mapping_size);
}
}
Note: to see the splat, CONFIG_TRANSPARENT_HUGEPAGE=y and
CONFIG_DEBUG_VM=y are needed.
Google Bug Id:
64696096
Link: http://lkml.kernel.org/r/20170823205235.132061-1-ebiggers3@gmail.com
Fixes:
854e9ed09ded ("mm: support madvise(MADV_FREE)")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org> [v4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ross Zwisler [Fri, 25 Aug 2017 22:55:36 +0000 (15:55 -0700)]
dax: fix deadlock due to misaligned PMD faults
In DAX there are two separate places where the 2MiB range of a PMD is
defined.
The first is in the page tables, where a PMD mapping inserted for a
given address spans from (vmf->address & PMD_MASK) to ((vmf->address &
PMD_MASK) + PMD_SIZE - 1). That is, from the 2MiB boundary below the
address to the 2MiB boundary above the address.
So, for example, a fault at address 3MiB (0x30 0000) falls within the
PMD that ranges from 2MiB (0x20 0000) to 4MiB (0x40 0000).
The second PMD range is in the mapping->page_tree, where a given file
offset is covered by a radix tree entry that spans from one 2MiB aligned
file offset to another 2MiB aligned file offset.
So, for example, the file offset for 3MiB (pgoff 768) falls within the
PMD range for the order 9 radix tree entry that ranges from 2MiB (pgoff
512) to 4MiB (pgoff 1024).
This system works so long as the addresses and file offsets for a given
mapping both have the same offsets relative to the start of each PMD.
Consider the case where the starting address for a given file isn't 2MiB
aligned - say our faulting address is 3 MiB (0x30 0000), but that
corresponds to the beginning of our file (pgoff 0). Now all the PMDs in
the mapping are misaligned so that the 2MiB range defined in the page
tables never matches up with the 2MiB range defined in the radix tree.
The current code notices this case for DAX faults to storage with the
following test in dax_pmd_insert_mapping():
if (pfn_t_to_pfn(pfn) & PG_PMD_COLOUR)
goto unlock_fallback;
This test makes sure that the pfn we get from the driver is 2MiB
aligned, and relies on the assumption that the 2MiB alignment of the pfn
we get back from the driver matches the 2MiB alignment of the faulting
address.
However, faults to holes were not checked and we could hit the problem
described above.
This was reported in response to the NVML nvml/src/test/pmempool_sync
TEST5:
$ cd nvml/src/test/pmempool_sync
$ make TEST5
You can grab NVML here:
https://github.com/pmem/nvml/
The dmesg warning you see when you hit this error is:
WARNING: CPU: 13 PID: 2900 at fs/dax.c:641 dax_insert_mapping_entry+0x2df/0x310
Where we notice in dax_insert_mapping_entry() that the radix tree entry
we are about to replace doesn't match the locked entry that we had
previously inserted into the tree. This happens because the initial
insertion was done in grab_mapping_entry() using a pgoff calculated from
the faulting address (vmf->address), and the replacement in
dax_pmd_load_hole() => dax_insert_mapping_entry() is done using
vmf->pgoff.
In our failure case those two page offsets (one calculated from
vmf->address, one using vmf->pgoff) point to different order 9 radix
tree entries.
This failure case can result in a deadlock because the radix tree unlock
also happens on the pgoff calculated from vmf->address. This means that
the locked radix tree entry that we swapped in to the tree in
dax_insert_mapping_entry() using vmf->pgoff is never unlocked, so all
future faults to that 2MiB range will block forever.
Fix this by validating that the faulting address's PMD offset matches
the PMD offset from the start of the file. This check is done at the
very beginning of the fault and covers faults that would have mapped to
storage as well as faults to holes. I left the COLOUR check in
dax_pmd_insert_mapping() in place in case we ever hit the insanity
condition where the alignment of the pfn we get from the driver doesn't
match the alignment of the userspace address.
Link: http://lkml.kernel.org/r/20170822222436.18926-1-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reported-by: "Slusarz, Marcin" <marcin.slusarz@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kirill A. Shutemov [Fri, 25 Aug 2017 22:55:33 +0000 (15:55 -0700)]
mm, shmem: fix handling /sys/kernel/mm/transparent_hugepage/shmem_enabled
/sys/kernel/mm/transparent_hugepage/shmem_enabled controls if we want
to allocate huge pages when allocate pages for private in-kernel shmem
mount.
Unfortunately, as Dan noticed, I've screwed it up and the only way to
make kernel allocate huge page for the mount is to use "force" there.
All other values will be effectively ignored.
Link: http://lkml.kernel.org/r/20170822144254.66431-1-kirill.shutemov@linux.intel.com
Fixes:
5a6e75f8110c ("shmem: prepare huge= mount option and sysfs knob")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org> [4.8+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Chen Yu [Fri, 25 Aug 2017 22:55:30 +0000 (15:55 -0700)]
PM/hibernate: touch NMI watchdog when creating snapshot
There is a problem that when counting the pages for creating the
hibernation snapshot will take significant amount of time, especially on
system with large memory. Since the counting job is performed with irq
disabled, this might lead to NMI lockup. The following warning were
found on a system with 1.5TB DRAM:
Freezing user space processes ... (elapsed 0.002 seconds) done.
OOM killer disabled.
PM: Preallocating image memory...
NMI watchdog: Watchdog detected hard LOCKUP on cpu 27
CPU: 27 PID: 3128 Comm: systemd-sleep Not tainted 4.13.0-0.rc2.git0.1.fc27.x86_64 #1
task:
ffff9f01971ac000 task.stack:
ffffb1a3f325c000
RIP: 0010:memory_bm_find_bit+0xf4/0x100
Call Trace:
swsusp_set_page_free+0x2b/0x30
mark_free_pages+0x147/0x1c0
count_data_pages+0x41/0xa0
hibernate_preallocate_memory+0x80/0x450
hibernation_snapshot+0x58/0x410
hibernate+0x17c/0x310
state_store+0xdf/0xf0
kobj_attr_store+0xf/0x20
sysfs_kf_write+0x37/0x40
kernfs_fop_write+0x11c/0x1a0
__vfs_write+0x37/0x170
vfs_write+0xb1/0x1a0
SyS_write+0x55/0xc0
entry_SYSCALL_64_fastpath+0x1a/0xa5
...
done (allocated
6590003 pages)
PM: Allocated
26360012 kbytes in 19.89 seconds (1325.28 MB/s)
It has taken nearly 20 seconds(2.10GHz CPU) thus the NMI lockup was
triggered. In case the timeout of the NMI watch dog has been set to 1
second, a safe interval should be
6590003/20 = 320k pages in theory.
However there might also be some platforms running at a lower frequency,
so feed the watchdog every 100k pages.
[yu.c.chen@intel.com: simplification]
Link: http://lkml.kernel.org/r/1503460079-29721-1-git-send-email-yu.c.chen@intel.com
[yu.c.chen@intel.com: use interval of 128k instead of 100k to avoid modulus]
Link: http://lkml.kernel.org/r/1503328098-5120-1-git-send-email-yu.c.chen@intel.com
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Reported-by: Jan Filipcewicz <jan.filipcewicz@intel.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Michal Hocko <mhocko@suse.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Len Brown <lenb@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christoph Hellwig [Thu, 24 Aug 2017 16:07:02 +0000 (18:07 +0200)]
virtio_pci: fix cpu affinity support
Commit
0b0f9dc5 ("Revert "virtio_pci: use shared interrupts for
virtqueues"") removed the adjustment of the pre_vectors for the virtio
MSI-X vector allocation which was added in commit
fb5e31d9 ("virtio:
allow drivers to request IRQ affinity when creating VQs"). This will
lead to an incorrect assignment of MSI-X vectors, and potential
deadlocks when offlining cpus.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Fixes:
0b0f9dc5 ("Revert "virtio_pci: use shared interrupts for virtqueues")
Reported-by: YASUAKI ISHIMATSU <yasu.isimatu@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Stefan Hajnoczi [Wed, 26 Jul 2017 14:32:23 +0000 (15:32 +0100)]
virtio_blk: fix incorrect message when disk is resized
The message printed on disk resize is incorrect. The following is
printed when resizing to 2 GiB:
$ truncate -s 1G test.img
$ qemu -device virtio-blk-pci,logical_block_size=4096,...
(qemu) block_resize drive1 2G
virtio_blk virtio0: new size:
4194304 4096-byte logical blocks (17.2 GB/16.0 GiB)
The virtio_blk capacity config field is in 512-byte sector units
regardless of logical_block_size as per the VIRTIO specification.
Therefore the message should read:
virtio_blk virtio0: new size: 524288 4096-byte logical blocks (2.15 GB/2.0 GiB)
Note that this only affects the printed message. Thankfully the actual
block device has the correct size because the block layer expects
capacity in sectors.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Bart Van Assche [Fri, 18 Aug 2017 22:52:54 +0000 (15:52 -0700)]
blk-mq-debugfs: Add names for recently added flags
The symbolic constants QUEUE_FLAG_SCSI_PASSTHROUGH, QUEUE_FLAG_QUIESCED
and REQ_NOWAIT are missing from blk-mq-debugfs.c. Add these to
blk-mq-debugfs.c such that these appear as names in debugfs instead of
as numbers.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Paul Mackerras [Thu, 24 Aug 2017 09:14:47 +0000 (19:14 +1000)]
KVM: PPC: Book3S: Fix race and leak in kvm_vm_ioctl_create_spapr_tce()
Nixiaoming pointed out that there is a memory leak in
kvm_vm_ioctl_create_spapr_tce() if the call to anon_inode_getfd()
fails; the memory allocated for the kvmppc_spapr_tce_table struct
is not freed, and nor are the pages allocated for the iommu
tables. In addition, we have already incremented the process's
count of locked memory pages, and this doesn't get restored on
error.
David Hildenbrand pointed out that there is a race in that the
function checks early on that there is not already an entry in the
stt->iommu_tables list with the same LIOBN, but an entry with the
same LIOBN could get added between then and when the new entry is
added to the list.
This fixes all three problems. To simplify things, we now call
anon_inode_getfd() before placing the new entry in the list. The
check for an existing entry is done while holding the kvm->lock
mutex, immediately before adding the new entry to the list.
Finally, on failure we now call kvmppc_account_memlimit to
decrement the process's count of locked memory pages.
Reported-by: Nixiaoming <nixiaoming@huawei.com>
Reported-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Mark Rutland [Thu, 22 Jun 2017 14:41:38 +0000 (15:41 +0100)]
perf/core: Fix group {cpu,task} validation
Regardless of which events form a group, it does not make sense for the
events to target different tasks and/or CPUs, as this leaves the group
inconsistent and impossible to schedule. The core perf code assumes that
these are consistent across (successfully intialised) groups.
Core perf code only verifies this when moving SW events into a HW
context. Thus, we can violate this requirement for pure SW groups and
pure HW groups, unless the relevant PMU driver happens to perform this
verification itself. These mismatched groups subsequently wreak havoc
elsewhere.
For example, we handle watchpoints as SW events, and reserve watchpoint
HW on a per-CPU basis at pmu::event_init() time to ensure that any event
that is initialised is guaranteed to have a slot at pmu::add() time.
However, the core code only checks the group leader's cpu filter (via
event_filter_match()), and can thus install follower events onto CPUs
violating thier (mismatched) CPU filters, potentially installing them
into a CPU without sufficient reserved slots.
This can be triggered with the below test case, resulting in warnings
from arch backends.
#define _GNU_SOURCE
#include <linux/hw_breakpoint.h>
#include <linux/perf_event.h>
#include <sched.h>
#include <stdio.h>
#include <sys/prctl.h>
#include <sys/syscall.h>
#include <unistd.h>
static int perf_event_open(struct perf_event_attr *attr, pid_t pid, int cpu,
int group_fd, unsigned long flags)
{
return syscall(__NR_perf_event_open, attr, pid, cpu, group_fd, flags);
}
char watched_char;
struct perf_event_attr wp_attr = {
.type = PERF_TYPE_BREAKPOINT,
.bp_type = HW_BREAKPOINT_RW,
.bp_addr = (unsigned long)&watched_char,
.bp_len = 1,
.size = sizeof(wp_attr),
};
int main(int argc, char *argv[])
{
int leader, ret;
cpu_set_t cpus;
/*
* Force use of CPU0 to ensure our CPU0-bound events get scheduled.
*/
CPU_ZERO(&cpus);
CPU_SET(0, &cpus);
ret = sched_setaffinity(0, sizeof(cpus), &cpus);
if (ret) {
printf("Unable to set cpu affinity\n");
return 1;
}
/* open leader event, bound to this task, CPU0 only */
leader = perf_event_open(&wp_attr, 0, 0, -1, 0);
if (leader < 0) {
printf("Couldn't open leader: %d\n", leader);
return 1;
}
/*
* Open a follower event that is bound to the same task, but a
* different CPU. This means that the group should never be possible to
* schedule.
*/
ret = perf_event_open(&wp_attr, 0, 1, leader, 0);
if (ret < 0) {
printf("Couldn't open mismatched follower: %d\n", ret);
return 1;
} else {
printf("Opened leader/follower with mismastched CPUs\n");
}
/*
* Open as many independent events as we can, all bound to the same
* task, CPU0 only.
*/
do {
ret = perf_event_open(&wp_attr, 0, 0, -1, 0);
} while (ret >= 0);
/*
* Force enable/disble all events to trigger the erronoeous
* installation of the follower event.
*/
printf("Opened all events. Toggling..\n");
for (;;) {
prctl(PR_TASK_PERF_EVENTS_DISABLE, 0, 0, 0, 0);
prctl(PR_TASK_PERF_EVENTS_ENABLE, 0, 0, 0, 0);
}
return 0;
}
Fix this by validating this requirement regardless of whether we're
moving events.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Zhou Chengming <zhouchengming1@huawei.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1498142498-15758-1-git-send-email-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Eric Biggers [Thu, 24 Aug 2017 17:50:29 +0000 (10:50 -0700)]
x86/mm: Fix use-after-free of ldt_struct
The following commit:
39a0526fb3f7 ("x86/mm: Factor out LDT init from context init")
renamed init_new_context() to init_new_context_ldt() and added a new
init_new_context() which calls init_new_context_ldt(). However, the
error code of init_new_context_ldt() was ignored. Consequently, if a
memory allocation in alloc_ldt_struct() failed during a fork(), the
->context.ldt of the new task remained the same as that of the old task
(due to the memcpy() in dup_mm()). ldt_struct's are not intended to be
shared, so a use-after-free occurred after one task exited.
Fix the bug by making init_new_context() pass through the error code of
init_new_context_ldt().
This bug was found by syzkaller, which encountered the following splat:
BUG: KASAN: use-after-free in free_ldt_struct.part.2+0x10a/0x150 arch/x86/kernel/ldt.c:116
Read of size 4 at addr
ffff88006d2cb7c8 by task kworker/u9:0/3710
CPU: 1 PID: 3710 Comm: kworker/u9:0 Not tainted 4.13.0-rc4-next-
20170811 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:16 [inline]
dump_stack+0x194/0x257 lib/dump_stack.c:52
print_address_description+0x73/0x250 mm/kasan/report.c:252
kasan_report_error mm/kasan/report.c:351 [inline]
kasan_report+0x24e/0x340 mm/kasan/report.c:409
__asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429
free_ldt_struct.part.2+0x10a/0x150 arch/x86/kernel/ldt.c:116
free_ldt_struct arch/x86/kernel/ldt.c:173 [inline]
destroy_context_ldt+0x60/0x80 arch/x86/kernel/ldt.c:171
destroy_context arch/x86/include/asm/mmu_context.h:157 [inline]
__mmdrop+0xe9/0x530 kernel/fork.c:889
mmdrop include/linux/sched/mm.h:42 [inline]
exec_mmap fs/exec.c:1061 [inline]
flush_old_exec+0x173c/0x1ff0 fs/exec.c:1291
load_elf_binary+0x81f/0x4ba0 fs/binfmt_elf.c:855
search_binary_handler+0x142/0x6b0 fs/exec.c:1652
exec_binprm fs/exec.c:1694 [inline]
do_execveat_common.isra.33+0x1746/0x22e0 fs/exec.c:1816
do_execve+0x31/0x40 fs/exec.c:1860
call_usermodehelper_exec_async+0x457/0x8f0 kernel/umh.c:100
ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
Allocated by task 3700:
save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
save_stack+0x43/0xd0 mm/kasan/kasan.c:447
set_track mm/kasan/kasan.c:459 [inline]
kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3627
kmalloc include/linux/slab.h:493 [inline]
alloc_ldt_struct+0x52/0x140 arch/x86/kernel/ldt.c:67
write_ldt+0x7b7/0xab0 arch/x86/kernel/ldt.c:277
sys_modify_ldt+0x1ef/0x240 arch/x86/kernel/ldt.c:307
entry_SYSCALL_64_fastpath+0x1f/0xbe
Freed by task 3700:
save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
save_stack+0x43/0xd0 mm/kasan/kasan.c:447
set_track mm/kasan/kasan.c:459 [inline]
kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
__cache_free mm/slab.c:3503 [inline]
kfree+0xca/0x250 mm/slab.c:3820
free_ldt_struct.part.2+0xdd/0x150 arch/x86/kernel/ldt.c:121
free_ldt_struct arch/x86/kernel/ldt.c:173 [inline]
destroy_context_ldt+0x60/0x80 arch/x86/kernel/ldt.c:171
destroy_context arch/x86/include/asm/mmu_context.h:157 [inline]
__mmdrop+0xe9/0x530 kernel/fork.c:889
mmdrop include/linux/sched/mm.h:42 [inline]
__mmput kernel/fork.c:916 [inline]
mmput+0x541/0x6e0 kernel/fork.c:927
copy_process.part.36+0x22e1/0x4af0 kernel/fork.c:1931
copy_process kernel/fork.c:1546 [inline]
_do_fork+0x1ef/0xfb0 kernel/fork.c:2025
SYSC_clone kernel/fork.c:2135 [inline]
SyS_clone+0x37/0x50 kernel/fork.c:2129
do_syscall_64+0x26c/0x8c0 arch/x86/entry/common.c:287
return_from_SYSCALL_64+0x0/0x7a
Here is a C reproducer:
#include <asm/ldt.h>
#include <pthread.h>
#include <signal.h>
#include <stdlib.h>
#include <sys/syscall.h>
#include <sys/wait.h>
#include <unistd.h>
static void *fork_thread(void *_arg)
{
fork();
}
int main(void)
{
struct user_desc desc = { .entry_number = 8191 };
syscall(__NR_modify_ldt, 1, &desc, sizeof(desc));
for (;;) {
if (fork() == 0) {
pthread_t t;
srand(getpid());
pthread_create(&t, NULL, fork_thread, NULL);
usleep(rand() % 10000);
syscall(__NR_exit_group, 0);
}
wait(NULL);
}
}
Note: the reproducer takes advantage of the fact that alloc_ldt_struct()
may use vmalloc() to allocate a large ->entries array, and after
commit:
5d17a73a2ebe ("vmalloc: back off when the current task is killed")
it is possible for userspace to fail a task's vmalloc() by
sending a fatal signal, e.g. via exit_group(). It would be more
difficult to reproduce this bug on kernels without that commit.
This bug only affected kernels with CONFIG_MODIFY_LDT_SYSCALL=y.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@vger.kernel.org> [v4.6+]
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Fixes:
39a0526fb3f7 ("x86/mm: Factor out LDT init from context init")
Link: http://lkml.kernel.org/r/20170824175029.76040-1-ebiggers3@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Paolo Bonzini [Wed, 23 Aug 2017 21:16:29 +0000 (23:16 +0200)]
KVM, pkeys: do not use PKRU value in vcpu->arch.guest_fpu.state
The host pkru is restored right after vcpu exit (commit
1be0e61), so
KVM_GET_XSAVE will return the host PKRU value instead. Fix this by
using the guest PKRU explicitly in fill_xsave and load_xsave. This
part is based on a patch by Junkang Fu.
The host PKRU data may also not match the value in vcpu->arch.guest_fpu.state,
because it could have been changed by userspace since the last time
it was saved, so skip loading it in kvm_load_guest_fpu.
Reported-by: Junkang Fu <junkang.fjk@alibaba-inc.com>
Cc: Yang Zhang <zy107165@alibaba-inc.com>
Fixes:
1be0e61c1f255faaeab04a390e00c8b9b9042870
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Wed, 23 Aug 2017 21:14:38 +0000 (23:14 +0200)]
KVM: x86: simplify handling of PKRU
Move it to struct kvm_arch_vcpu, replacing guest_pkru_valid with a
simple comparison against the host value of the register. The write of
PKRU in addition can be skipped if the guest has not enabled the feature.
Once we do this, we need not test OSPKE in the host anymore, because
guest_CR4.PKE=1 implies host_CR4.PKE=1.
The static PKU test is kept to elide the code on older CPUs.
Suggested-by: Yang Zhang <zy107165@alibaba-inc.com>
Fixes:
1be0e61c1f255faaeab04a390e00c8b9b9042870
Cc: stable@vger.kernel.org
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Thu, 24 Aug 2017 09:59:31 +0000 (11:59 +0200)]
KVM: x86: block guest protection keys unless the host has them enabled
If the host has protection keys disabled, we cannot read and write the
guest PKRU---RDPKRU and WRPKRU fail with #GP(0) if CR4.PKE=0. Block
the PKU cpuid bit in that case.
This ensures that guest_CR4.PKE=1 implies host_CR4.PKE=1.
Fixes:
1be0e61c1f255faaeab04a390e00c8b9b9042870
Cc: stable@vger.kernel.org
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Boris Brezillon [Wed, 23 Aug 2017 18:45:01 +0000 (20:45 +0200)]
mtd: nand: atmel: Relax tADL_min constraint
Version 4 of the ONFI spec mandates that tADL be at least 400 nanoseconds,
but, depending on the master clock rate, 400 ns may not fit in the tADL
field of the SMC reg. We need to relax the check and accept the -ERANGE
return code.
Note that previous versions of the ONFI spec had a lower tADL_min (100 or
200 ns). It's not clear why this timing constraint got increased but it
seems most NANDs are fine with values lower than 400ns, so we should be
safe.
Fixes:
f9ce2eddf176 ("mtd: nand: atmel: Add ->setup_data_interface() hooks")
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Uwe Kleine-König [Wed, 23 Aug 2017 07:03:04 +0000 (09:03 +0200)]
mtd: nandsim: remove debugfs entries in error path
The debugfs entries must be removed before an error is returned in the
probe function. Otherwise another try to load the module fails and when
the debugfs files are accessed without the module loaded, the kernel
still tries to call a function in that module.
Fixes:
5346c27c5fed ("mtd: nandsim: Introduce debugfs infrastructure")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Richard Weinberger <richard@nod.at>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Dave Airlie [Thu, 24 Aug 2017 23:29:38 +0000 (09:29 +1000)]
Merge tag 'drm-misc-fixes-2017-08-24' of git://anongit.freedesktop.org/git/drm-misc into drm-fixes
Core Changes:
- Release driver tracking before making the object available again (Chris)
Cc: Chris Wilson <chris@chris-wilson.co.uk>
* tag 'drm-misc-fixes-2017-08-24' of git://anongit.freedesktop.org/git/drm-misc:
drm: Release driver tracking before making the object available again
Dave Airlie [Thu, 24 Aug 2017 23:29:06 +0000 (09:29 +1000)]
Merge tag 'drm-intel-fixes-2017-08-24' of git://anongit.freedesktop.org/git/drm-intel into drm-fixes
drm/i915 fixes for v4.13-rc7
* tag 'drm-intel-fixes-2017-08-24' of git://anongit.freedesktop.org/git/drm-intel:
drm/i915/gvt: Fix the kernel null pointer error
drm/i915: Clear lost context-switch interrupts across reset
drm/i915/bxt: use NULL for GPIO connection ID
drm/i915/cnl: Fix LSPCON support.
drm/i915/vbt: ignore extraneous child devices for a port
drm/i915: Initialize 'data' in intel_dsi_dcs_backlight.c
Masaki Ota [Thu, 24 Aug 2017 22:44:36 +0000 (15:44 -0700)]
Input: ALPS - fix two-finger scroll breakage in right side on ALPS touchpad
Fixed the issue that two finger scroll does not work correctly
on V8 protocol. The cause is that V8 protocol X-coordinate decode
is wrong at SS4 PLUS device. I added SS4 PLUS X decode definition.
Mote notes:
the problem manifests itself by the commit
e7348396c6d5 ("Input: ALPS
- fix V8+ protocol handling (73 03 28)"), where a fix for the V8+
protocol was applied. Although the culprit must have been present
beforehand, the two-finger scroll worked casually even with the
wrongly reported values by some reason. It got broken by the commit
above just because it changed x_max value, and this made libinput
correctly figuring the MT events. Since the X coord is reported as
falsely doubled, the events on the right-half side go outside the
boundary, thus they are no longer handled. This resulted as a broken
two-finger scroll.
One finger event is decoded differently, and it didn't suffer from
this problem. The problem was only about MT events. --tiwai
Fixes:
e7348396c6d5 ("Input: ALPS - fix V8+ protocol handling (73 03 28)")
Signed-off-by: Masaki Ota <masaki.ota@jp.alps.com>
Tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Paul Donohue <linux-kernel@PaulSD.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Linus Torvalds [Thu, 24 Aug 2017 22:48:38 +0000 (15:48 -0700)]
Merge tag 'for-linus' of git://git./linux/kernel/git/dledford/rdma
Pull more rdma fixes from Doug Ledford:
"Well, I thought we were going to be done for this -rc cycle. I should
have known better than to say so though.
We have four additional items that trickled in.
One was a simple mistake on my part. I took a patch into my for-next
thinking that the issue was less severe than it was. I was then
notified that it needed to be in my -rc area instead.
The other three were just found late in testing.
Summary:
- One core fix accidentally applied first to for-next and then cherry
picked back because it needed to be in the -rc cycles instead
- Another core fix
- Two mlx5 fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma:
IB/mlx5: Always return success for RoCE modify port
IB/mlx5: Fix Raw Packet QP event handler assignment
IB/core: Avoid accessing non-allocated memory when inferring port type
RDMA/uverbs: Initialize cq_context appropriately
Vadim Lomovtsev [Mon, 21 Aug 2017 11:23:07 +0000 (07:23 -0400)]
net: sunrpc: svcsock: fix NULL-pointer exception
While running nfs/connectathon tests kernel NULL-pointer exception
has been observed due to races in svcsock.c.
Race is appear when kernel accepts connection by kernel_accept
(which creates new socket) and start queuing ingress packets
to new socket. This happens in ksoftirq context which could run
concurrently on a different core while new socket setup is not done yet.
The fix is to re-order socket user data init sequence and add
write/read barrier calls to be sure that we got proper values
for callback pointers before actually calling them.
Test results: nfs/connectathon reports '0' failed tests for about 200+ iterations.
Crash log:
---<-snip->---
[ 6708.638984] Unable to handle kernel NULL pointer dereference at virtual address
00000000
[ 6708.647093] pgd =
ffff0000094e0000
[ 6708.650497] [
00000000] *pgd=
0000010ffff90003, *pud=
0000010ffff90003, *pmd=
0000010ffff80003, *pte=
0000000000000000
[ 6708.660761] Internal error: Oops:
86000005 [#1] SMP
[ 6708.665630] Modules linked in: nfsv3 nfnetlink_queue nfnetlink_log nfnetlink rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache overlay xt_CONNSECMARK xt_SECMARK xt_conntrack iptable_security ip_tables ah4 xfrm4_mode_transport sctp tun binfmt_misc ext4 jbd2 mbcache loop tcp_diag udp_diag inet_diag rpcrdma ib_isert iscsi_target_mod ib_iser rdma_cm iw_cm libiscsi scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp ib_ipoib ib_ucm ib_uverbs ib_umad ib_cm ib_core nls_koi8_u nls_cp932 ts_kmp nf_conntrack_ipv4 nf_defrag_ipv4 nf_conntrack vfat fat ghash_ce sha2_ce sha1_ce cavium_rng_vf i2c_thunderx sg thunderx_edac i2c_smbus edac_core cavium_rng nfsd auth_rpcgss nfs_acl lockd grace sunrpc xfs libcrc32c nicvf nicpf ast i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops
[ 6708.736446] ttm drm i2c_core thunder_bgx thunder_xcv mdio_thunder mdio_cavium dm_mirror dm_region_hash dm_log dm_mod [last unloaded: stap_3c300909c5b3f46dcacd49aab3334af_87021]
[ 6708.752275] CPU: 84 PID: 0 Comm: swapper/84 Tainted: G W OE 4.11.0-4.el7.aarch64 #1
[ 6708.760787] Hardware name: www.cavium.com CRB-2S/CRB-2S, BIOS 0.3 Mar 13 2017
[ 6708.767910] task:
ffff810006842e80 task.stack:
ffff81000689c000
[ 6708.773822] PC is at 0x0
[ 6708.776739] LR is at svc_data_ready+0x38/0x88 [sunrpc]
[ 6708.781866] pc : [<
0000000000000000>] lr : [<
ffff0000029d7378>] pstate:
60000145
[ 6708.789248] sp :
ffff810ffbad3900
[ 6708.792551] x29:
ffff810ffbad3900 x28:
ffff000008c73d58
[ 6708.797853] x27:
0000000000000000 x26:
ffff81000bbe1e00
[ 6708.803156] x25:
0000000000000020 x24:
ffff800f7410bf28
[ 6708.808458] x23:
ffff000008c63000 x22:
ffff000008c63000
[ 6708.813760] x21:
ffff800f7410bf28 x20:
ffff81000bbe1e00
[ 6708.819063] x19:
ffff810012412400 x18:
00000000d82a9df2
[ 6708.824365] x17:
0000000000000000 x16:
0000000000000000
[ 6708.829667] x15:
0000000000000000 x14:
0000000000000001
[ 6708.834969] x13:
0000000000000000 x12:
722e736f622e676e
[ 6708.840271] x11:
00000000f814dd99 x10:
0000000000000000
[ 6708.845573] x9 :
7374687225000000 x8 :
0000000000000000
[ 6708.850875] x7 :
0000000000000000 x6 :
0000000000000000
[ 6708.856177] x5 :
0000000000000028 x4 :
0000000000000000
[ 6708.861479] x3 :
0000000000000000 x2 :
00000000e5000000
[ 6708.866781] x1 :
0000000000000000 x0 :
ffff81000bbe1e00
[ 6708.872084]
[ 6708.873565] Process swapper/84 (pid: 0, stack limit = 0xffff81000689c000)
[ 6708.880341] Stack: (0xffff810ffbad3900 to 0xffff8100068a0000)
[ 6708.886075] Call trace:
[ 6708.888513] Exception stack(0xffff810ffbad3710 to 0xffff810ffbad3840)
[ 6708.894942] 3700:
ffff810012412400 0001000000000000
[ 6708.902759] 3720:
ffff810ffbad3900 0000000000000000 0000000060000145 ffff800f79300000
[ 6708.910577] 3740:
ffff000009274d00 00000000000003ea 0000000000000015 ffff000008c63000
[ 6708.918395] 3760:
ffff810ffbad3830 ffff800f79300000 000000000000004d 0000000000000000
[ 6708.926212] 3780:
ffff810ffbad3890 ffff0000080f88dc ffff800f79300000 000000000000004d
[ 6708.934030] 37a0:
ffff800f7930093c ffff000008c63000 0000000000000000 0000000000000140
[ 6708.941848] 37c0:
ffff000008c2c000 0000000000040b00 ffff81000bbe1e00 0000000000000000
[ 6708.949665] 37e0:
00000000e5000000 0000000000000000 0000000000000000 0000000000000028
[ 6708.957483] 3800:
0000000000000000 0000000000000000 0000000000000000 7374687225000000
[ 6708.965300] 3820:
0000000000000000 00000000f814dd99 722e736f622e676e 0000000000000000
[ 6708.973117] [< (null)>] (null)
[ 6708.977824] [<
ffff0000086f9fa4>] tcp_data_queue+0x754/0xc5c
[ 6708.983386] [<
ffff0000086fa64c>] tcp_rcv_established+0x1a0/0x67c
[ 6708.989384] [<
ffff000008704120>] tcp_v4_do_rcv+0x15c/0x22c
[ 6708.994858] [<
ffff000008707418>] tcp_v4_rcv+0xaf0/0xb58
[ 6709.000077] [<
ffff0000086df784>] ip_local_deliver_finish+0x10c/0x254
[ 6709.006419] [<
ffff0000086dfea4>] ip_local_deliver+0xf0/0xfc
[ 6709.011980] [<
ffff0000086dfad4>] ip_rcv_finish+0x208/0x3a4
[ 6709.017454] [<
ffff0000086e018c>] ip_rcv+0x2dc/0x3c8
[ 6709.022328] [<
ffff000008692fc8>] __netif_receive_skb_core+0x2f8/0xa0c
[ 6709.028758] [<
ffff000008696068>] __netif_receive_skb+0x38/0x84
[ 6709.034580] [<
ffff00000869611c>] netif_receive_skb_internal+0x68/0xdc
[ 6709.041010] [<
ffff000008696bc0>] napi_gro_receive+0xcc/0x1a8
[ 6709.046690] [<
ffff0000014b0fc4>] nicvf_cq_intr_handler+0x59c/0x730 [nicvf]
[ 6709.053559] [<
ffff0000014b1380>] nicvf_poll+0x38/0xb8 [nicvf]
[ 6709.059295] [<
ffff000008697a6c>] net_rx_action+0x2f8/0x464
[ 6709.064771] [<
ffff000008081824>] __do_softirq+0x11c/0x308
[ 6709.070164] [<
ffff0000080d14e4>] irq_exit+0x12c/0x174
[ 6709.075206] [<
ffff00000813101c>] __handle_domain_irq+0x78/0xc4
[ 6709.081027] [<
ffff000008081608>] gic_handle_irq+0x94/0x190
[ 6709.086501] Exception stack(0xffff81000689fdf0 to 0xffff81000689ff20)
[ 6709.092929] fde0:
0000810ff2ec0000 ffff000008c10000
[ 6709.100747] fe00:
ffff000008c70ef4 0000000000000001 0000000000000000 ffff810ffbad9b18
[ 6709.108565] fe20:
ffff810ffbad9c70 ffff8100169d3800 ffff810006843ab0 ffff81000689fe80
[ 6709.116382] fe40:
0000000000000bd0 0000ffffdf979cd0 183f5913da192500 0000ffff8a254ce4
[ 6709.124200] fe60:
0000ffff8a254b78 0000aaab10339808 0000000000000000 0000ffff8a0c2a50
[ 6709.132018] fe80:
0000ffffdf979b10 ffff000008d6d450 ffff000008c10000 ffff000008d6d000
[ 6709.139836] fea0:
0000000000000054 ffff000008cd3dbc 0000000000000000 0000000000000000
[ 6709.147653] fec0:
0000000000000000 0000000000000000 0000000000000000 ffff81000689ff20
[ 6709.155471] fee0:
ffff000008085240 ffff81000689ff20 ffff000008085244 0000000060000145
[ 6709.163289] ff00:
ffff81000689ff10 ffff00000813f1e4 ffffffffffffffff ffff00000813f238
[ 6709.171107] [<
ffff000008082eb4>] el1_irq+0xb4/0x140
[ 6709.175976] [<
ffff000008085244>] arch_cpu_idle+0x44/0x11c
[ 6709.181368] [<
ffff0000087bf3b8>] default_idle_call+0x20/0x30
[ 6709.187020] [<
ffff000008116d50>] do_idle+0x158/0x1e4
[ 6709.191973] [<
ffff000008116ff4>] cpu_startup_entry+0x2c/0x30
[ 6709.197624] [<
ffff00000808e7cc>] secondary_start_kernel+0x13c/0x160
[ 6709.203878] [<
0000000001bc71c4>] 0x1bc71c4
[ 6709.207967] Code: bad PC value
[ 6709.211061] SMP: stopping secondary CPUs
[ 6709.218830] Starting crashdump kernel...
[ 6709.222749] Bye!
---<-snip>---
Signed-off-by: Vadim Lomovtsev <vlomovts@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Chuck Lever [Fri, 18 Aug 2017 15:12:19 +0000 (11:12 -0400)]
nfsd: Limit end of page list when decoding NFSv4 WRITE
When processing an NFSv4 WRITE operation, argp->end should never
point past the end of the data in the final page of the page list.
Otherwise, nfsd4_decode_compound can walk into uninitialized memory.
More critical, nfsd4_decode_write is failing to increment argp->pagelen
when it increments argp->pagelist. This can cause later xdr decoders
to assume more data is available than really is, which can cause server
crashes on malformed requests.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Linus Torvalds [Thu, 24 Aug 2017 21:56:20 +0000 (14:56 -0700)]
Merge tag 'acpi-4.13-rc7' of git://git./linux/kernel/git/rafael/linux-pm
Pull ACPI fixes from Rafael Wysocki:
"These fix two recent regressions (in ACPICA and in the ACPI EC driver)
and one bug in code introduced during the 4.12 cycle (ACPI device
properties library routine).
Specifics:
- Fix a regression in the ACPI EC driver causing a kernel to crash
during initialization on some systems due to a code ordering issue
exposed by a recent change (Lv Zheng).
- Fix a recent regression in ACPICA due to a change of the behavior
of a library function in a way that is not backwards compatible
with some existing callers of it (Rafael Wysocki).
- Fix a coding mistake in a library function related to the handling
of ACPI device properties introduced during the 4.12 cycle (Sakari
Ailus)"
* tag 'acpi-4.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: device property: Fix node lookup in acpi_graph_get_child_prop_value()
ACPICA: Fix acpi_evaluate_object_typed()
ACPI: EC: Fix regression related to wrong ECDT initialization order
Linus Torvalds [Thu, 24 Aug 2017 21:22:27 +0000 (14:22 -0700)]
Merge tag 'kbuild-fixes-v4.13' of git://git./linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
- fix linker script regression caused by dead code elimination support
- fix typos and outdated comments
- specify kselftest-clean as a PHONY target
- fix "make dtbs_install" when $(srctree) includes shell special
characters like '~'
- Move -fshort-wchar to the global option list because defining it
partially emits warnings
* tag 'kbuild-fixes-v4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: update comments of Makefile.asm-generic
kbuild: Do not use hyphen in exported variable name
Makefile: add kselftest-clean to PHONY target list
Kbuild: use -fshort-wchar globally
fixdep: trivial: typo fix and correction
kbuild: trivial cleanups on the comments
kbuild: linker script do not match C names unless LD_DEAD_CODE_DATA_ELIMINATION is configured
Linus Torvalds [Thu, 24 Aug 2017 21:10:31 +0000 (14:10 -0700)]
Merge branch 'for-4.13-rc7' of git://git./linux/kernel/git/kdave/linux
Pull btrfs fix from David Sterba:
"We have one more fixup that stems from the blk_status_t conversion
that did not quite cover everything.
The normal cases were not affected because the code is 0, but any
error and retries could mix up new and old values"
* 'for-4.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix blk_status_t/errno confusion
Linus Torvalds [Thu, 24 Aug 2017 21:08:22 +0000 (14:08 -0700)]
Merge tag 'trace-v4.13-rc3' of git://git./linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Various bug fixes:
- Two small memory leaks in error paths.
- A missed return error code on an error path.
- A fix to check the tracing ring buffer CPU when it doesn't exist
(caused by setting maxcpus on the command line that is less than
the actual number of CPUs, and then onlining them manually).
- A fix to have the reset of boot tracers called by lateinit_sync()
instead of just lateinit(). As some of the tracers register via
lateinit(), and if the clear happens before the tracer is
registered, it will never start even though it was told to via the
kernel command line"
* tag 'trace-v4.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix freeing of filter in create_filter() when set_str is false
tracing: Fix kmemleak in tracing_map_array_free()
ftrace: Check for null ret_stack on profile function graph entry function
ring-buffer: Have ring_buffer_alloc_read_page() return error on offline CPU
tracing: Missing error code in tracer_alloc_buffers()
tracing: Call clear_boot_tracer() at lateinit_sync
Linus Torvalds [Thu, 24 Aug 2017 21:01:18 +0000 (14:01 -0700)]
Merge tag 'armsoc-fixes' of git://git./linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Arnd Bergmann:
"A small number of bugfixes, again nothing serious.
- Alexander Dahl found multiple bugs in the Atmel memory interface
driver
- A randconfig build fix for at91 was incomplete, the second attempt
fixes the remaining corner case
- One fix for the TI Keystone queue handler
- The Odroid XU4 HDMI port (added in 4.13) needs a small DT fix"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
ARM: dts: exynos: add needs-hpd for Odroid-XU3/4
ARM: at91: don't select CONFIG_ARM_CPU_SUSPEND for old platforms
soc: ti: knav: Add a NULL pointer check for kdev in knav_pool_create
memory: atmel-ebi: Fix smc cycle xlate converter
memory: atmel-ebi: Allow t_DF timings of zero ns
memory: atmel-ebi: Fix smc timing return value evaluation
Eric W. Biederman [Thu, 24 Aug 2017 20:13:29 +0000 (15:13 -0500)]
pty: Repair TIOCGPTPEER
The implementation of TIOCGPTPEER has two issues.
When /dev/ptmx (as opposed to /dev/pts/ptmx) is opened the wrong
vfsmount is passed to dentry_open. Which results in the kernel displaying
the wrong pathname for the peer.
The second is simply by caching the vfsmount and dentry of the peer it leaves
them open, in a way they were not previously Which because of the inreased
reference counts can cause unnecessary behaviour differences resulting in
regressions.
To fix these move the ioctl into tty_io.c at a generic level allowing
the ioctl to have access to the struct file on which the ioctl is
being called. This allows the path of the slave to be derived when
opening the slave through TIOCGPTPEER instead of requiring the path to
the slave be cached. Thus removing the need for caching the path.
A new function devpts_ptmx_path is factored out of devpts_acquire and
used to implement a function devpts_mntget. The new function devpts_mntget
takes a filp to perform the lookup on and fsi so that it can confirm
that the superblock that is found by devpts_ptmx_path is the proper superblock.
v2: Lots of fixes to make the code actually work
v3: Suggestions by Linus
- Removed the unnecessary initialization of filp in ptm_open_peer
- Simplified devpts_ptmx_path as gotos are no longer required
[ This is the fix for the issue that was reverted in commit
143c97cc6529, but this time without breaking 'pbuilder' due to
increased reference counts - Linus ]
Fixes:
54ebbfb16034 ("tty: add TIOCGPTPEER ioctl")
Reported-by: Christian Brauner <christian.brauner@canonical.com>
Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rafael J. Wysocki [Thu, 24 Aug 2017 20:22:53 +0000 (22:22 +0200)]
Merge branches 'acpica-fix', 'acpi-ec-fix' and 'acpi-properties-fix'
* acpica-fix:
ACPICA: Fix acpi_evaluate_object_typed()
* acpi-ec-fix:
ACPI: EC: Fix regression related to wrong ECDT initialization order
* acpi-properties-fix:
ACPI: device property: Fix node lookup in acpi_graph_get_child_prop_value()
Majd Dibbiny [Wed, 23 Aug 2017 05:35:42 +0000 (08:35 +0300)]
IB/mlx5: Always return success for RoCE modify port
CM layer calls ib_modify_port() regardless of the link layer.
For the Ethernet ports, qkey violation and Port capabilities
are meaningless. Therefore, always return success for ib_modify_port
calls on the Ethernet ports.
Cc: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Majd Dibbiny <majd@mellanox.com>
Reviewed-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Majd Dibbiny [Wed, 23 Aug 2017 05:35:41 +0000 (08:35 +0300)]
IB/mlx5: Fix Raw Packet QP event handler assignment
In case we have SQ and RQ for Raw Packet QP, the SQ's event handler
wasn't assigned.
Fixing this by assigning event handler for each WQ after creation.
[ 1877.145243] Call Trace:
[ 1877.148644] <IRQ>
[ 1877.150580] [<
ffffffffa07987c5>] ? mlx5_rsc_event+0x105/0x210 [mlx5_core]
[ 1877.159581] [<
ffffffffa0795bd7>] ? mlx5_cq_event+0x57/0xd0 [mlx5_core]
[ 1877.167137] [<
ffffffffa079208e>] mlx5_eq_int+0x53e/0x6c0 [mlx5_core]
[ 1877.174526] [<
ffffffff8101a679>] ? sched_clock+0x9/0x10
[ 1877.180753] [<
ffffffff810f717e>] handle_irq_event_percpu+0x3e/0x1e0
[ 1877.188014] [<
ffffffff810f735d>] handle_irq_event+0x3d/0x60
[ 1877.194567] [<
ffffffff810f9fe7>] handle_edge_irq+0x77/0x130
[ 1877.201129] [<
ffffffff81014c3f>] handle_irq+0xbf/0x150
[ 1877.207244] [<
ffffffff815ed78a>] ? atomic_notifier_call_chain+0x1a/0x20
[ 1877.214829] [<
ffffffff815f434f>] do_IRQ+0x4f/0xf0
[ 1877.220498] [<
ffffffff815e94ad>] common_interrupt+0x6d/0x6d
[ 1877.227025] <EOI>
[ 1877.228967] [<
ffffffff814834e2>] ? cpuidle_enter_state+0x52/0xc0
[ 1877.236990] [<
ffffffff81483615>] cpuidle_idle_call+0xc5/0x200
[ 1877.243676] [<
ffffffff8101bc7e>] arch_cpu_idle+0xe/0x30
[ 1877.249831] [<
ffffffff810b4725>] cpu_startup_entry+0xf5/0x290
[ 1877.256513] [<
ffffffff815cfee1>] start_secondary+0x265/0x27b
[ 1877.263111] Code: Bad RIP value.
[ 1877.267296] RIP [< (null)>] (null)
[ 1877.273264] RSP <
ffff88046fd63df8>
[ 1877.277531] CR2:
0000000000000000
Fixes:
19098df2da78 ("IB/mlx5: Refactor mlx5_ib_qp to accommodate other QP types")
Signed-off-by: Majd Dibbiny <majd@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Noa Osherovich [Wed, 23 Aug 2017 05:35:40 +0000 (08:35 +0300)]
IB/core: Avoid accessing non-allocated memory when inferring port type
Commit
44c58487d51a ("IB/core: Define 'ib' and 'roce' rdma_ah_attr types")
introduced the concept of type in ah_attr:
* During ib_register_device, each port is checked for its type which
is stored in ib_device's port_immutable array.
* During uverbs' modify_qp, the type is inferred using the port number
in ib_uverbs_qp_dest struct (address vector) by accessing the
relevant port_immutable array and the type is passed on to
providers.
IB spec (version 1.3) enforces a valid port value only in Reset to
Init. During Init to RTR, the address vector must be valid but port
number is not mentioned as a field in the address vector, so its
value is not validated, which leads to accesses to a non-allocated
memory when inferring the port type.
Save the real port number in ib_qp during modify to Init (when the
comp_mask indicates that the port number is valid) and use this value
to infer the port type.
Avoid copying the address vector fields if the matching bit is not set
in the attr_mask. Address vector can't be modified before the port, so
no valid flow is affected.
Fixes:
44c58487d51a ('IB/core: Define 'ib' and 'roce' rdma_ah_attr types')
Signed-off-by: Noa Osherovich <noaos@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Tom Rini [Wed, 23 Aug 2017 01:51:46 +0000 (21:51 -0400)]
ASoC: rt5677: Reintroduce I2C device IDs
Not all devices with ACPI and this combination of sound devices will
have the required information provided via ACPI. Reintroduce the I2C
device ID to restore sound functionality on on the Chromebook 'Samus'
model.
[ More background note:
the commit
a36afb0ab648 ("ASoC: rt5677: Introduce proper table...")
moved the i2c ID probed via ACPI ("RT5677CE:00") to a proper
acpi_device_id table. Although the action itself is correct per se,
the overseen issue is the reference id->driver_data at
rt5677_i2c_probe() for retrieving the corresponding chip model for
the given id. Since id=NULL is passed for ACPI matching case, we get
an Oops now.
We already have queued more fixes for 4.14 and they already address
the issue, but they are bigger changes that aren't preferable for the
late 4.13-rc stage. So, this patch just papers over the bug as a
once-off quick fix for a particular ACPI matching. -- tiwai ]
Fixes:
a36afb0ab648 ("ASoC: rt5677: Introduce proper table for ACPI enumeration")
Signed-off-by: Tom Rini <trini@konsulko.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Omar Sandoval [Wed, 23 Aug 2017 06:45:59 +0000 (23:45 -0700)]
Btrfs: fix blk_status_t/errno confusion
This fixes several instances of blk_status_t and bare errno ints being
mixed up, some of which are real bugs.
In the normal case, 0 matches BLK_STS_OK, so we don't observe any
effects of the missing conversion, but in case of errors or passes
through the repair/retry paths, the errors get mixed up.
The changes were identified using 'sparse', we don't have reports of the
buggy behaviour.
Fixes:
4e4cbee93d56 ("block: switch bios to blk_status_t")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Cao jin [Tue, 22 Aug 2017 13:09:53 +0000 (21:09 +0800)]
kbuild: update comments of Makefile.asm-generic
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Benjamin Block [Wed, 23 Aug 2017 23:57:56 +0000 (01:57 +0200)]
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer
Since we split the scsi_request out of struct request bsg fails to
provide a reply-buffer for the drivers. This was done via the pointer
for sense-data, that is not preallocated anymore.
Failing to allocate/assign it results in illegal dereferences because
LLDs use this pointer unquestioned.
An example panic on s390x, using the zFCP driver, looks like this (I had
debugging on, otherwise NULL-pointer dereferences wouldn't even panic on
s390x):
Unable to handle kernel pointer dereference in virtual kernel address space
Failing address:
6b6b6b6b6b6b6000 TEID:
6b6b6b6b6b6b6403
Fault in home space mode while using kernel ASCE.
AS:
0000000001590007 R3:
0000000000000024
Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Modules linked in: <Long List>
CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3
Hardware name: IBM 2964 N96 702 (z/VM 6.4.0)
task:
0000000065cb0100 task.stack:
0000000065cb4000
Krnl PSW :
0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp])
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3
Krnl GPRS:
0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866
000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f
00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38
0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8
Krnl Code:
000003ff801e4146:
e31020500004 lg %r1,80(%r2)
000003ff801e414c:
58402040 l %r4,64(%r2)
#
000003ff801e4150:
e35020200004 lg %r5,32(%r2)
>
000003ff801e4156:
50405004 st %r4,4(%r5)
000003ff801e415a:
e54c50080000 mvhi 8(%r5),0
000003ff801e4160:
e33010280012 lt %r3,40(%r1)
000003ff801e4166:
a718fffb lhi %r1,-5
000003ff801e416a: 1803 lr %r0,%r3
Call Trace:
([<
000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp])
[<
000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp]
[<
000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp]
[<
00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8
[<
00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10
[<
00000000001684c2>] tasklet_action+0x15a/0x1d8
[<
0000000000bd28ec>] __do_softirq+0x3ec/0x848
[<
00000000001675a4>] irq_exit+0x74/0xf8
[<
000000000010dd6a>] do_IRQ+0xba/0xf0
[<
0000000000bd19e8>] io_int_handler+0x104/0x2d4
[<
00000000001033b6>] enabled_wait+0xb6/0x188
([<
000000000010339e>] enabled_wait+0x9e/0x188)
[<
000000000010396a>] arch_cpu_idle+0x32/0x50
[<
0000000000bd0112>] default_idle_call+0x52/0x68
[<
00000000001cd0fa>] do_idle+0x102/0x188
[<
00000000001cd41e>] cpu_startup_entry+0x3e/0x48
[<
0000000000118c64>] smp_start_secondary+0x11c/0x130
[<
0000000000bd2016>] restart_int_handler+0x62/0x78
[<
0000000000000000>] (null)
INFO: lockdep is turned off.
Last Breaking-Event-Address:
[<
000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp]
Kernel panic - not syncing: Fatal exception in interrupt
This patch moves bsg-lib to allocate and setup struct bsg_job ahead of
time, including the allocation of a buffer for the reply-data.
This means, struct bsg_job is not allocated separately anymore, but as part
of struct request allocation - similar to struct scsi_cmd. Reflect this in
the function names that used to handle creation/destruction of struct
bsg_job.
Reported-by: Steffen Maier <maier@linux.vnet.ibm.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Fixes:
82ed4db499b8 ("block: split scsi_request out of struct request")
Cc: <stable@vger.kernel.org> #4.11+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Steven Rostedt (VMware) [Wed, 23 Aug 2017 16:46:27 +0000 (12:46 -0400)]
tracing: Fix freeing of filter in create_filter() when set_str is false
Performing the following task with kmemleak enabled:
# cd /sys/kernel/tracing/events/irq/irq_handler_entry/
# echo 'enable_event:kmem:kmalloc:3 if irq >' > trigger
# echo 'enable_event:kmem:kmalloc:3 if irq > 31' > trigger
# echo scan > /sys/kernel/debug/kmemleak
# cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff8800b9290308 (size 32):
comm "bash", pid 1114, jiffies
4294848451 (age 141.139s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<
ffffffff81cef5aa>] kmemleak_alloc+0x4a/0xa0
[<
ffffffff81357938>] kmem_cache_alloc_trace+0x158/0x290
[<
ffffffff81261c09>] create_filter_start.constprop.28+0x99/0x940
[<
ffffffff812639c9>] create_filter+0xa9/0x160
[<
ffffffff81263bdc>] create_event_filter+0xc/0x10
[<
ffffffff812655e5>] set_trigger_filter+0xe5/0x210
[<
ffffffff812660c4>] event_enable_trigger_func+0x324/0x490
[<
ffffffff812652e2>] event_trigger_write+0x1a2/0x260
[<
ffffffff8138cf87>] __vfs_write+0xd7/0x380
[<
ffffffff8138f421>] vfs_write+0x101/0x260
[<
ffffffff8139187b>] SyS_write+0xab/0x130
[<
ffffffff81cfd501>] entry_SYSCALL_64_fastpath+0x1f/0xbe
[<
ffffffffffffffff>] 0xffffffffffffffff
The function create_filter() is passed a 'filterp' pointer that gets
allocated, and if "set_str" is true, it is up to the caller to free it, even
on error. The problem is that the pointer is not freed by create_filter()
when set_str is false. This is a bug, and it is not up to the caller to free
the filter on error if it doesn't care about the string.
Link: http://lkml.kernel.org/r/1502705898-27571-2-git-send-email-chuhu@redhat.com
Cc: stable@vger.kernel.org
Fixes:
38b78eb85 ("tracing: Factorize filter creation")
Reported-by: Chunyu Hu <chuhu@redhat.com>
Tested-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Chunyu Hu [Mon, 14 Aug 2017 10:18:17 +0000 (18:18 +0800)]
tracing: Fix kmemleak in tracing_map_array_free()
kmemleak reported the below leak when I was doing clear of the hist
trigger. With this patch, the kmeamleak is gone.
unreferenced object 0xffff94322b63d760 (size 32):
comm "bash", pid 1522, jiffies
4403687962 (age 2442.311s)
hex dump (first 32 bytes):
00 01 00 00 04 00 00 00 08 00 00 00 ff 00 00 00 ................
10 00 00 00 00 00 00 00 80 a8 7a f2 31 94 ff ff ..........z.1...
backtrace:
[<
ffffffff9e96c27a>] kmemleak_alloc+0x4a/0xa0
[<
ffffffff9e424cba>] kmem_cache_alloc_trace+0xca/0x1d0
[<
ffffffff9e377736>] tracing_map_array_alloc+0x26/0x140
[<
ffffffff9e261be0>] kretprobe_trampoline+0x0/0x50
[<
ffffffff9e38b935>] create_hist_data+0x535/0x750
[<
ffffffff9e38bd47>] event_hist_trigger_func+0x1f7/0x420
[<
ffffffff9e38893d>] event_trigger_write+0xfd/0x1a0
[<
ffffffff9e44dfc7>] __vfs_write+0x37/0x170
[<
ffffffff9e44f552>] vfs_write+0xb2/0x1b0
[<
ffffffff9e450b85>] SyS_write+0x55/0xc0
[<
ffffffff9e203857>] do_syscall_64+0x67/0x150
[<
ffffffff9e977ce7>] return_from_SYSCALL_64+0x0/0x6a
[<
ffffffffffffffff>] 0xffffffffffffffff
unreferenced object 0xffff9431f27aa880 (size 128):
comm "bash", pid 1522, jiffies
4403687962 (age 2442.311s)
hex dump (first 32 bytes):
00 00 8c 2a 32 94 ff ff 00 f0 8b 2a 32 94 ff ff ...*2......*2...
00 e0 8b 2a 32 94 ff ff 00 d0 8b 2a 32 94 ff ff ...*2......*2...
backtrace:
[<
ffffffff9e96c27a>] kmemleak_alloc+0x4a/0xa0
[<
ffffffff9e425348>] __kmalloc+0xe8/0x220
[<
ffffffff9e3777c1>] tracing_map_array_alloc+0xb1/0x140
[<
ffffffff9e261be0>] kretprobe_trampoline+0x0/0x50
[<
ffffffff9e38b935>] create_hist_data+0x535/0x750
[<
ffffffff9e38bd47>] event_hist_trigger_func+0x1f7/0x420
[<
ffffffff9e38893d>] event_trigger_write+0xfd/0x1a0
[<
ffffffff9e44dfc7>] __vfs_write+0x37/0x170
[<
ffffffff9e44f552>] vfs_write+0xb2/0x1b0
[<
ffffffff9e450b85>] SyS_write+0x55/0xc0
[<
ffffffff9e203857>] do_syscall_64+0x67/0x150
[<
ffffffff9e977ce7>] return_from_SYSCALL_64+0x0/0x6a
[<
ffffffffffffffff>] 0xffffffffffffffff
Link: http://lkml.kernel.org/r/1502705898-27571-1-git-send-email-chuhu@redhat.com
Cc: stable@vger.kernel.org
Fixes:
08d43a5fa063 ("tracing: Add lock-free tracing_map")
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Steven Rostedt (VMware) [Thu, 17 Aug 2017 20:37:25 +0000 (16:37 -0400)]
ftrace: Check for null ret_stack on profile function graph entry function
There's a small race when function graph shutsdown and the calling of the
registered function graph entry callback. The callback must not reference
the task's ret_stack without first checking that it is not NULL. Note, when
a ret_stack is allocated for a task, it stays allocated until the task exits.
The problem here, is that function_graph is shutdown, and a new task was
created, which doesn't have its ret_stack allocated. But since some of the
functions are still being traced, the callbacks can still be called.
The normal function_graph code handles this, but starting with commit
8861dd303c ("ftrace: Access ret_stack->subtime only in the function
profiler") the profiler code references the ret_stack on function entry, but
doesn't check if it is NULL first.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=196611
Cc: stable@vger.kernel.org
Fixes:
8861dd303c ("ftrace: Access ret_stack->subtime only in the function profiler")
Reported-by: lilydjwg@gmail.com
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Benjamin Herrenschmidt [Fri, 18 Aug 2017 02:10:58 +0000 (12:10 +1000)]
KVM: PPC: Book3S HV: Add missing barriers to XIVE code and document them
This adds missing memory barriers to order updates/tests of
the virtual CPPR and MFRR, thus fixing a lost IPI problem.
While at it also document all barriers in this file.
This fixes a bug causing guest IPIs to occasionally get lost. The
symptom then is hangs or stalls in the guest.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Benjamin Herrenschmidt [Fri, 18 Aug 2017 02:10:52 +0000 (12:10 +1000)]
KVM: PPC: Book3S HV: Workaround POWER9 DD1.0 bug causing IPB bit loss
This adds a workaround for a bug in POWER9 DD1 chips where changing
the CPPR (Current Processor Priority Register) can cause bits in the
IPB (Interrupt Pending Buffer) to get lost. Thankfully it only
happens when manually manipulating CPPR which is quite rare. When it
does happen it can cause interrupts to be delayed or lost.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Nicholas Piggin [Sun, 12 Mar 2017 17:03:49 +0000 (03:03 +1000)]
KVM: PPC: Book3S HV: Use msgsync with hypervisor doorbells on POWER9
When msgsnd is used for IPIs to other cores, msgsync must be executed by
the target to order stores performed on the source before its msgsnd
(provided the source executes the appropriate sync).
Fixes:
1704a81ccebc ("KVM: PPC: Book3S HV: Use msgsnd for IPIs to other cores on POWER9")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Nicholas Piggin [Tue, 22 Aug 2017 08:43:48 +0000 (18:43 +1000)]
timers: Fix excessive granularity of new timers after a nohz idle
When a timer base is idle, it is forwarded when a new timer is added
to ensure that granularity does not become excessive. When not idle,
the timer tick is expected to increment the base.
However there are several problems:
- If an existing timer is modified, the base is forwarded only after
the index is calculated.
- The base is not forwarded by add_timer_on.
- There is a window after a timer is restarted from a nohz idle, after
it is marked not-idle and before the timer tick on this CPU, where a
timer may be added but the ancient base does not get forwarded.
These result in excessive granularity (a 1 jiffy timeout can blow out
to 100s of jiffies), which cause the rcu lockup detector to trigger,
among other things.
Fix this by keeping track of whether the timer base has been idle
since it was last run or forwarded, and if so then forward it before
adding a new timer.
There is still a case where mod_timer optimises the case of a pending
timer mod with the same expiry time, where the timer can see excessive
granularity relative to the new, shorter interval. A comment is added,
but it's not changed because it is an important fastpath for
networking.
This has been tested and found to fix the RCU softlockup messages.
Testing was also done with tracing to measure requested versus
achieved wakeup latencies for all non-deferrable timers in an idle
system (with no lockup watchdogs running). Wakeup latency relative to
absolute latency is calculated (note this suffers from round-up skew
at low absolute times) and analysed:
max avg std
upstream 506.0 1.20 4.68
patched 2.0 1.08 0.15
The bug was noticed due to the lockup detector Kconfig changes
dropping it out of people's .configs and resulting in larger base
clk skew When the lockup detectors are enabled, no CPU can go idle for
longer than 4 seconds, which limits the granularity errors.
Sub-optimal timer behaviour is observable on a smaller scale in that
case:
max avg std
upstream 9.0 1.05 0.19
patched 2.0 1.04 0.11
Fixes: Fixes:
a683f390b93f ("timers: Forward the wheel clock whenever possible")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: David Miller <davem@davemloft.net>
Cc: dzickus@redhat.com
Cc: sfr@canb.auug.org.au
Cc: mpe@ellerman.id.au
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: linuxarm@huawei.com
Cc: abdhalee@linux.vnet.ibm.com
Cc: John Stultz <john.stultz@linaro.org>
Cc: akpm@linux-foundation.org
Cc: paulmck@linux.vnet.ibm.com
Cc: torvalds@linux-foundation.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20170822084348.21436-1-npiggin@gmail.com
Linus Torvalds [Thu, 24 Aug 2017 01:16:11 +0000 (18:16 -0700)]
Revert "pty: fix the cached path of the pty slave file descriptor in the master"
This reverts commit
c8c03f1858331e85d397bacccd34ef409aae993c.
It turns out that while fixing the ptmx file descriptor to have the
correct 'struct path' to the associated slave pty is a really good
thing, it breaks some user space tools for a very annoying reason.
The problem is that /dev/ptmx and its associated slave pty (/dev/pts/X)
are on different mounts. That was what caused us to have the wrong path
in the first place (we would mix up the vfsmount of the 'ptmx' node,
with the dentry of the pty slave node), but it also means that now while
we use the right vfsmount, having the pty master open also keeps the pts
mount busy.
And it turn sout that that makes 'pbuilder' very unhappy, as noted by
Stefan Lippers-Hollmann:
"This patch introduces a regression for me when using pbuilder
0.228.7[2] (a helper to build Debian packages in a chroot and to
create and update its chroots) when trying to umount /dev/ptmx (inside
the chroot) on Debian/ unstable (full log and pbuilder configuration
file[3] attached).
[...]
Setting up build-essential (12.3) ...
Processing triggers for libc-bin (2.24-15) ...
I: unmounting dev/ptmx filesystem
W: Could not unmount dev/ptmx: umount: /var/cache/pbuilder/build/1340/dev/ptmx: target is busy
(In some cases useful info about processes that
use the device is found by lsof(8) or fuser(1).)"
apparently pbuilder tries to unmount the /dev/pts filesystem while still
holding at least one master node open, which is arguably not very nice,
but we don't break user space even when fixing other bugs.
So this commit has to be reverted.
I'll try to figure out a way to avoid caching the path to the slave pty
in the master pty. The only thing that actually wants that slave pty
path is the "TIOCGPTPEER" ioctl, and I think we could just recreate the
path at that time.
Reported-by: Stefan Lippers-Hollmann <s.l-h@gmx.de>
Cc: Eric W Biederman <ebiederm@xmission.com>
Cc: Christian Brauner <christian.brauner@canonical.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Omar Sandoval [Wed, 23 Aug 2017 21:54:59 +0000 (14:54 -0700)]
Revert "loop: support 4k physical blocksize"
There's some stuff still up in the air, let's not get stuck with a
subpar ABI. I'll follow up with something better for 4.14.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Shaohua Li [Fri, 18 Aug 2017 23:08:13 +0000 (16:08 -0700)]
blk-throttle: cap discard request size
discard request usually is very big and easily use all bandwidth budget
of a cgroup. discard request size doesn't really mean the size of data
written, so it doesn't make sense to account it into bandwidth budget.
Jens pointed out treating the size 0 doesn't make sense too, because
discard request does have cost. But it's not easy to find the actual
cost. This patch simply makes the size one sector.
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Hans Verkuil [Wed, 23 Aug 2017 16:24:50 +0000 (18:24 +0200)]
ARM: dts: exynos: add needs-hpd for Odroid-XU3/4
CEC support was added for Exynos5 in 4.13, but for the Odroids we need to set
'needs-hpd' as well since CEC is disabled when there is no HDMI hotplug signal,
just as for the exynos4 Odroid-U3.
This is due to the level-shifter that is disabled when there is no HPD, thus
blocking the CEC signal as well. Same close-but-no-cigar board design as the
Odroid-U3.
Tested with my Odroid XU4.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Linus Torvalds [Wed, 23 Aug 2017 19:05:46 +0000 (12:05 -0700)]
Merge tag 'arm64-fixes' of git://git./linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"Late arm64 fixes.
They fix very early boot failures with KASLR where the early mapping
of the kernel is incorrect, so the failure mode looks like a hang with
no output. There's also a signal-handling fix when a uaccess routine
faults with a fatal signal pending, which could be used to create
unkillable user tasks using userfaultfd and finally a state leak fix
for the floating pointer registers across a call to exec().
We're still seeing some random issues crop up (inode memory corruption
and spinlock recursion) but we've not managed to reproduce things
reliably enough to debug or bisect them yet.
Summary:
- Fix very early boot failures with KASLR enabled
- Fix fatal signal handling on userspace access from kernel
- Fix leakage of floating point register state across exec()"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: kaslr: Adjust the offset to avoid Image across alignment boundary
arm64: kaslr: ignore modulo offset when validating virtual displacement
arm64: mm: abort uaccess retries upon fatal signal
arm64: fpsimd: Prevent registers leaking across exec
Linus Torvalds [Wed, 23 Aug 2017 18:43:38 +0000 (11:43 -0700)]
Merge tag 'gpio-v4.13-3' of git://git./linux/kernel/git/linusw/linux-gpio
Pull GPIO fixes from Linus Walleij:
"Here are the (hopefully) last GPIO fixes for v4.13:
- an important core fix to reject invalid GPIOs *before* trying to
obtain a GPIO descriptor for it.
- a driver fix for the mvebu driver IRQ handling"
* tag 'gpio-v4.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
gpio: mvebu: Fix cause computation in irq handler
gpio: reject invalid gpio before getting gpio_desc
Ronnie Sahlberg [Wed, 23 Aug 2017 04:48:14 +0000 (14:48 +1000)]
cifs: return ENAMETOOLONG for overlong names in cifs_open()/cifs_lookup()
Add checking for the path component length and verify it is <= the maximum
that the server advertizes via FileFsAttributeInformation.
With this patch cifs.ko will now return ENAMETOOLONG instead of ENOENT
when users to access an overlong path.
To test this, try to cd into a (non-existing) directory on a CIFS share
that has a too long name:
cd /mnt/
aaaaaaaaaaaaaaa...
and it now should show a good error message from the shell:
bash: cd: /mnt/
aaaaaaaaaaaaaaaa...aaaaaa: File name too long
rh bz
1153996
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Cc: <stable@vger.kernel.org>
Linus Torvalds [Wed, 23 Aug 2017 18:34:40 +0000 (11:34 -0700)]
Merge tag 'scsi-fixes' of git://git./linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Six minor and error leg fixes, plus one major change: the reversion of
scsi-mq as the default.
We're doing the latter temporarily (with a backport to stable) to give
us time to fix all the issues that turned up with this default before
trying again"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: cxgb4i: call neigh_event_send() to update MAC address
Revert "scsi: default to scsi-mq"
scsi: sd_zbc: Write unlock zone from sd_uninit_cmnd()
scsi: aacraid: Fix out of bounds in aac_get_name_resp
scsi: csiostor: fail probe if fw does not support FCoE
scsi: megaraid_sas: fix error handle in megasas_probe_one
Sachin Prabhu [Thu, 3 Aug 2017 07:39:03 +0000 (13:09 +0530)]
cifs: Fix df output for users with quota limits
The df for a SMB2 share triggers a GetInfo call for
FS_FULL_SIZE_INFORMATION. The values returned are used to populate
struct statfs.
The problem is that none of the information returned by the call
contains the total blocks available on the filesystem. Instead we use
the blocks available to the user ie. quota limitation when filling out
statfs.f_blocks. The information returned does contain Actual free units
on the filesystem and is used to populate statfs.f_bfree. For users with
quota enabled, it can lead to situations where the total free space
reported is more than the total blocks on the system ending up with df
reports like the following
# df -h /mnt/a
Filesystem Size Used Avail Use% Mounted on
//192.168.22.10/a 2.5G -2.3G 2.5G - /mnt/a
To fix this problem, we instead populate both statfs.f_bfree with the
same value as statfs.f_bavail ie. CallerAvailableAllocationUnits. This
is similar to what is done already in the code for cifs and df now
reports the quota information for the user used to mount the share.
# df --si /mnt/a
Filesystem Size Used Avail Use% Mounted on
//192.168.22.10/a 2.7G 101M 2.6G 4% /mnt/a
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Pierguido Lambri <plambri@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Cc: <stable@vger.kernel.org>
Arnd Bergmann [Wed, 23 Aug 2017 14:46:15 +0000 (16:46 +0200)]
ARM: at91: don't select CONFIG_ARM_CPU_SUSPEND for old platforms
My previous patch fixed a link error for all at91 platforms when
CONFIG_ARM_CPU_SUSPEND was not set, however this caused another
problem on a configuration that enabled CONFIG_ARCH_AT91 but none
of the individual SoCs, and that also enabled CPU_ARM720 as
the only CPU:
warning: (ARCH_AT91 && SOC_IMX23 && SOC_IMX28 && ARCH_PXA && MACH_MVEBU_V7 && SOC_IMX6 && ARCH_OMAP3 && ARCH_OMAP4 && SOC_OMAP5 && SOC_AM33XX && SOC_DRA7XX && ARCH_EXYNOS3 && ARCH_EXYNOS4 && EXYNOS5420_MCPM && EXYNOS_CPU_SUSPEND && ARCH_VEXPRESS_TC2_PM && ARM_BIG_LITTLE_CPUIDLE && ARM_HIGHBANK_CPUIDLE && QCOM_PM) selects ARM_CPU_SUSPEND which has unmet direct dependencies (ARCH_SUSPEND_POSSIBLE)
arch/arm/kernel/sleep.o: In function `cpu_resume':
(.text+0xf0): undefined reference to `cpu_arm720_suspend_size'
arch/arm/kernel/suspend.o: In function `__cpu_suspend_save':
suspend.c:(.text+0x134): undefined reference to `cpu_arm720_do_suspend'
This improves the hack some more by only selecting ARM_CPU_SUSPEND
for the part that requires it, and changing pm.c to drop the
contents of unused init functions so we no longer refer to
cpu_resume on at91 platforms that don't need it.
Fixes:
cc7a938f5f30 ("ARM: at91: select CONFIG_ARM_CPU_SUSPEND")
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Jani Nikula [Wed, 23 Aug 2017 08:48:04 +0000 (11:48 +0300)]
Merge tag 'gvt-fixes-2017-08-23' of https://github.com/01org/gvt-linux into drm-intel-fixes
gvt-fixes-2017-08-23
- Fix possible null ptr reference in error path (Fred)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170823075352.nlo7hp3bplnb5ilx@zhen-hp.sh.intel.com
Takashi Iwai [Wed, 23 Aug 2017 07:30:17 +0000 (09:30 +0200)]
ALSA: hda - Add stereo mic quirk for Lenovo G50-70 (17aa:3978)
Lenovo G50-70 (17aa:3978) with Conexant codec chip requires the
similar workaround for the inverted stereo dmic like other Lenovo
models.
Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=
1020657
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>