GitHub/LineageOS/G12/android_kernel_amlogic_linux-4.9.git
9 years agox86/asm/entry/64: Rename 'old_rsp' to 'rsp_scratch'
Ingo Molnar [Tue, 17 Mar 2015 13:42:59 +0000 (14:42 +0100)]
x86/asm/entry/64: Rename 'old_rsp' to 'rsp_scratch'

Make clear that the usage of PER_CPU(old_rsp) is purely temporary,
by renaming it to 'rsp_scratch'.

Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Update comments about stack frames
Ingo Molnar [Tue, 17 Mar 2015 13:42:59 +0000 (14:42 +0100)]
x86/asm/entry/64: Update comments about stack frames

Tweak a few outdated comments that were obsoleted by recent changes
to syscall entry code:

 - we no longer have a "partial stack frame" on
   entry, ever.

 - explain the syscall entry usage of old_rsp.

Partially based on a (split out of) patch from Denys Vlasenko.

Originally-from: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Remove thread_struct::usersp
Ingo Molnar [Tue, 17 Mar 2015 13:42:59 +0000 (14:42 +0100)]
x86/asm/entry/64: Remove thread_struct::usersp

Nothing uses thread_struct::usersp anymore, so remove it.

Originally-from: Denys Vlasenko <dvlasenk@redhat.com>
Tested-by: Borislav Petkov <bp@alien8.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Simplify 'old_rsp' usage
Ingo Molnar [Tue, 17 Mar 2015 13:42:59 +0000 (14:42 +0100)]
x86/asm/entry/64: Simplify 'old_rsp' usage

Remove all manipulations of PER_CPU(old_rsp) in C code:

 - it is not used on SYSRET return anymore, and system entries
   are atomic, so updating it from the fork and context switch
   paths is pointless.

 - Tweak a few related comments as well: we no longer have a
   "partial stack frame" on entry, ever.

Based on (split out of) patch from Denys Vlasenko.

Originally-from: Denys Vlasenko <dvlasenk@redhat.com>
Tested-by: Borislav Petkov <bp@alien8.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1426599779-8010-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Enable interrupts *after* we fetch PER_CPU_VAR(old_rsp)
Denys Vlasenko [Tue, 17 Mar 2015 13:52:24 +0000 (14:52 +0100)]
x86/asm/entry/64: Enable interrupts *after* we fetch PER_CPU_VAR(old_rsp)

We want to use PER_CPU_VAR(old_rsp) as a simple temporary register,
to shuffle user-space RSP into (and from) when we set up the system
call stack frame. At that point we cannot shuffle values into general
purpose registers, because we have not saved them yet.

To be able to do this shuffling into a memory location, we must be
atomic and must not be preempted while we do the shuffling, otherwise
the 'temporary' register gets overwritten by some other task's
temporary register contents ...

Tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1426600344-8254-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry: Document and clean up the enable_sep_cpu() and syscall32_cpu_init...
Ingo Molnar [Mon, 16 Mar 2015 09:32:20 +0000 (10:32 +0100)]
x86/asm/entry: Document and clean up the enable_sep_cpu() and syscall32_cpu_init() functions

Clean up the flow and document the functions a bit better.

Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/32: Document the 32-bit SYSENTER "emergency stack" better
Denys Vlasenko [Mon, 9 Mar 2015 14:52:18 +0000 (15:52 +0100)]
x86/asm/entry/32: Document the 32-bit SYSENTER "emergency stack" better

Before the patch, the 'tss_struct::stack' field was not referenced anywhere.

It was used only to set SYSENTER's stack to point after the last byte
of tss_struct, thus the trailing field, stack[64], was used.

But grep would not know it. You can comment it out, compile,
and kernel will even run until an unlucky NMI corrupts
io_bitmap[] (which is also not easily detectable).

This patch changes code so that the purpose and usage of this
field is not mysterious anymore, and can be easily grepped for.

This does change generated code, for a subtle reason:
since tss_struct is ____cacheline_aligned, there happens to be
5 longs of padding at the end. Old code was using the padding
too; new code will strictly use it only for SYSENTER_stack[].

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1425912738-559-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agoinclude/stddef.h: Move offsetofend() from vfio.h to a generic kernel header
Denys Vlasenko [Mon, 9 Mar 2015 14:52:17 +0000 (15:52 +0100)]
include/stddef.h: Move offsetofend() from vfio.h to a generic kernel header

Suggested by Andy.

Suggested-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1425912738-559-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry: Simplify task_pt_regs() macro definition
Denys Vlasenko [Fri, 13 Mar 2015 14:09:03 +0000 (15:09 +0100)]
x86/asm/entry: Simplify task_pt_regs() macro definition

Before this change, task_pt_regs() was using KSTK_TOP(),
and it was the only use of that macro. In turn, KSTK_TOP used
THREAD_SIZE_LONGS, and it was the only use of that macro too.

Fold these macros into task_pt_regs(). Tweak comment
about "- 8" - we now use a symbolic constant, not literal 8.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1426255743-5394-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/32: Document our abuse of x86_hw_tss::ss1 and x86_hw_tss::sp1
Andy Lutomirski [Tue, 10 Mar 2015 18:06:00 +0000 (11:06 -0700)]
x86/asm/entry/32: Document our abuse of x86_hw_tss::ss1 and x86_hw_tss::sp1

This has confused me for a while.  Now that I figured it out, document it.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/b7efc1b7364039824776f68e9ddee9ec1500e894.1426009661.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry: Unify and fix initial thread_struct::sp0 values
Andy Lutomirski [Tue, 10 Mar 2015 18:05:59 +0000 (11:05 -0700)]
x86/asm/entry: Unify and fix initial thread_struct::sp0 values

x86_32 and x86_64 need slightly different thread_struct::sp0 values, and
x86_32's was incorrect for init.

This never mattered -- the init thread never runs user code, so we never
used thread_struct::sp0 for anything.

Fix it and mostly unify them.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1b810c1d2e797e27bb4a7708c426101161edd1f6.1426009661.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry: Create and use a 'TOP_OF_KERNEL_STACK_PADDING' macro
Andy Lutomirski [Tue, 10 Mar 2015 18:05:58 +0000 (11:05 -0700)]
x86/asm/entry: Create and use a 'TOP_OF_KERNEL_STACK_PADDING' macro

x86_32, unlike x86_64, pads the top of the kernel stack, because the
hardware stack frame formats are variable in size.

Document this padding and give it a name.

This should make no change whatsoever to the compiled kernel
image. It also doesn't fix any of the current bugs in this area.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/02bf2f54b8dcb76a62a142b6dfe07d4ef7fc582e.1426009661.git.luto@amacapital.net
[ Fixed small details, such as a missed magic constant in entry_32.S pointed out by Denys Vlasenko. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/signal/64: Remove 'fs' and 'gs' from sigcontext
Andy Lutomirski [Thu, 12 Mar 2015 20:57:52 +0000 (13:57 -0700)]
x86/signal/64: Remove 'fs' and 'gs' from sigcontext

As far as I can tell, these fields have been set to zero on save
and ignored on restore since Linux was imported into git.
Rename them '__pad1' and '__pad2' to avoid confusion.  This may
also allow us to recycle them some day.

This also adds a comment clarifying the history of those fields.

I'm intentionally avoiding calling either of them '__pad0': the
field formerly known as '__pad0' is now 'ss'.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/844f8490e938780c03355be4c9b69eb4c494bf4e.1426193719.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/signal/64: Fix SS handling for signals delivered to 64-bit programs
Andy Lutomirski [Thu, 12 Mar 2015 20:57:51 +0000 (13:57 -0700)]
x86/signal/64: Fix SS handling for signals delivered to 64-bit programs

The comment in the signal code says that apps can save/restore
other segments on their own.  It's true that apps can *save* SS
on their own, but there's no way for apps to restore it: SYSCALL
effectively resets SS to __USER_DS, so any value that user code
tries to load into SS gets lost on entry to sigreturn.

This recycles two padding bytes in the segment selector area for SS.

While we're at it, we need a second change to make this useful.

If the signal we're delivering is caused by a bad SS value,
saving that value isn't enough.  We need to remove that bad
value from the regs before we try to deliver the signal.  Oddly,
the i386 code already got this right.

I suspect that 64-bit programs that try to run 16-bit code and
use signals will have a lot of trouble without this.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/405594361340a2ec32f8e2b115c142df0e180d8e.1426193719.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Save user RSP in pt_regs->sp on SYSCALL64 fastpath
Denys Vlasenko [Mon, 9 Mar 2015 18:39:23 +0000 (19:39 +0100)]
x86/asm/entry/64: Save user RSP in pt_regs->sp on SYSCALL64 fastpath

Prepare for the removal of 'usersp', by simplifying PER_CPU(old_rsp) usage:

  - use it only as temp storage

  - store the userspace stack pointer immediately in pt_regs->sp
    on syscall entry, instead of using it later, on syscall exit.

  - change C code to use pt_regs->sp only, instead of PER_CPU(old_rsp)
    and task->thread.usersp.

FIXUP/RESTORE_TOP_OF_STACK are simplified as well.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1425926364-9526-4-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Remove stub_iopl
Denys Vlasenko [Tue, 10 Mar 2015 10:45:06 +0000 (11:45 +0100)]
x86/asm/entry/64: Remove stub_iopl

stub_iopl is no longer needed: pt_regs->flags needs no fixing up
after previous change. Remove it.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1425984307-2143-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Save R11 into pt_regs->flags on SYSCALL64 fastpath
Denys Vlasenko [Mon, 9 Mar 2015 18:39:21 +0000 (19:39 +0100)]
x86/asm/entry/64: Save R11 into pt_regs->flags on SYSCALL64 fastpath

Before this patch, R11 was saved in pt_regs->r11.

Which looks natural, but requires messy shuffling to/from iret
frame whenever ptrace or e.g. sys_iopl() wants to modify flags -
because that's how this register is used by SYSCALL/SYSRET.

This patch saves R11 in pt_regs->flags, and uses that value for
the SYSRET64 instruction. Shuffling is eliminated.

FIXUP/RESTORE_TOP_OF_STACK are simplified.

stub_iopl is no longer needed: pt_regs->flags needs no fixing up.

Testing shows that syscall fast path is ~54.3 ns before
and after the patch (on 2.7 GHz Sandy Bridge CPU).

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1425926364-9526-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm: Optimize unnecessarily wide TEST instructions
Denys Vlasenko [Fri, 6 Mar 2015 20:55:32 +0000 (21:55 +0100)]
x86/asm: Optimize unnecessarily wide TEST instructions

By the nature of the TEST operation, it is often possible to test
a narrower part of the operand:

    "testl $3,  mem"  ->  "testb $3, mem",
    "testq $3, %rcx"  ->  "testb $3, %cl"

This results in shorter instructions, because the TEST instruction
has no sign-entending byte-immediate forms unlike other ALU ops.

Note that this change does not create any LCP (Length-Changing Prefix)
stalls, which happen when adding a 0x66 prefix, which happens when
16-bit immediates are used, which changes such TEST instructions:

  [test_opcode] [modrm] [imm32]

to:

  [0x66] [test_opcode] [modrm] [imm16]

where [imm16] has a *different length* now: 2 bytes instead of 4.
This confuses the decoder and slows down execution.

REX prefixes were carefully designed to almost never hit this case:
adding REX prefix does not change instruction length except MOVABS
and MOV [addr],RAX instruction.

This patch does not add instructions which would use a 0x66 prefix,
code changes in assembly are:

    -48 f7 07 01 00 00 00  testq  $0x1,(%rdi)
    +f6 07 01              testb  $0x1,(%rdi)
    -48 f7 c1 01 00 00 00  test   $0x1,%rcx
    +f6 c1 01              test   $0x1,%cl
    -48 f7 c1 02 00 00 00  test   $0x2,%rcx
    +f6 c1 02              test   $0x2,%cl
    -41 f7 c2 01 00 00 00  test   $0x1,%r10d
    +41 f6 c2 01           test   $0x1,%r10b
    -48 f7 c1 04 00 00 00  test   $0x4,%rcx
    +f6 c1 04              test   $0x4,%cl
    -48 f7 c1 08 00 00 00  test   $0x8,%rcx
    +f6 c1 08              test   $0x8,%cl

Linus further notes:

   "There are no stalls from using 8-bit instruction forms.

    Now, changing from 64-bit or 32-bit 'test' instructions to 8-bit ones
    *could* cause problems if it ends up having forwarding issues, so that
    instead of just forwarding the result, you end up having to wait for
    it to be stable in the L1 cache (or possibly the register file). The
    forwarding from the store buffer is simplest and most reliable if the
    read is done at the exact same address and the exact same size as the
    write that gets forwarded.

    But that's true only if:

     (a) the write was very recent and is still in the write queue. I'm
         not sure that's the case here anyway.

     (b) on at least most Intel microarchitectures, you have to test a
         different byte than the lowest one (so forwarding a 64-bit write
         to a 8-bit read ends up working fine, as long as the 8-bit read
         is of the low 8 bits of the written data).

    A very similar issue *might* show up for registers too, not just
    memory writes, if you use 'testb' with a high-byte register (where
    instead of forwarding the value from the original producer it needs to
    go through the register file and then shifted). But it's mainly a
    problem for store buffers.

    But afaik, the way Denys changed the test instructions, neither of the
    above issues should be true.

    The real problem for store buffer forwarding tends to be "write 8
    bits, read 32 bits". That can be really surprisingly expensive,
    because the read ends up having to wait until the write has hit the
    cacheline, and we might talk tens of cycles of latency here. But
    "write 32 bits, read the low 8 bits" *should* be fast on pretty much
    all x86 chips, afaik."

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1425675332-31576-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry: Replace this_cpu_sp0() with current_top_of_stack() and fix it on x86_32
Andy Lutomirski [Sat, 7 Mar 2015 01:50:19 +0000 (17:50 -0800)]
x86/asm/entry: Replace this_cpu_sp0() with current_top_of_stack() and fix it on x86_32

I broke 32-bit kernels.  The implementation of sp0 was correct
as far as I can tell, but sp0 was much weirder on x86_32 than I
realized.  It has the following issues:

 - Init's sp0 is inconsistent with everything else's: non-init tasks
   are offset by 8 bytes.  (I have no idea why, and the comment is unhelpful.)

 - vm86 does crazy things to sp0.

Fix it up by replacing this_cpu_sp0() with
current_top_of_stack() and using a new percpu variable to track
the top of the stack on x86_32.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 75182b1632a8 ("x86/asm/entry: Switch all C consumers of kernel_stack to this_cpu_sp0()")
Link: http://lkml.kernel.org/r/d09dbe270883433776e0cbee3c7079433349e96d.1425692936.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry: Delay loading sp0 slightly on task switch
Andy Lutomirski [Sat, 7 Mar 2015 01:50:18 +0000 (17:50 -0800)]
x86/asm/entry: Delay loading sp0 slightly on task switch

The change:

  75182b1632a8 ("x86/asm/entry: Switch all C consumers of kernel_stack to this_cpu_sp0()")

had the unintended side effect of changing the return value of
current_thread_info() during part of the context switch process.
Change it back.

This has no effect as far as I can tell -- it's just for
consistency.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/9fcaa47dd8487db59eed7a3911b6ae409476763e.1425692936.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry: Rename 'INIT_TSS_IST' to 'CPU_TSS_IST'
Andy Lutomirski [Fri, 6 Mar 2015 03:19:07 +0000 (19:19 -0800)]
x86/asm/entry: Rename 'INIT_TSS_IST' to 'CPU_TSS_IST'

This has nothing to do with the init thread or the initial
anything. It's just the CPU's TSS.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/a0bd5e26b32a2e1f08ff99017d0997118fbb2485.1425611534.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry: Remove INIT_TSS and fold the definitions into 'cpu_tss'
Andy Lutomirski [Fri, 6 Mar 2015 03:19:06 +0000 (19:19 -0800)]
x86/asm/entry: Remove INIT_TSS and fold the definitions into 'cpu_tss'

The INIT_TSS is unnecessary.  Just define the initial TSS where
'cpu_tss' is defined.

While we're at it, merge the 32-bit and 64-bit definitions.  The
only syntactic change is that 32-bit kernels were computing sp0
as long, but now they compute it as unsigned long.

Verified by objdump: the contents and relocations of
.data..percpu..shared_aligned are unchanged on 32-bit and 64-bit
kernels.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/8fc39fa3f6c5d635e93afbdd1a0fe0678a6d7913.1425611534.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry: Rename 'init_tss' to 'cpu_tss'
Andy Lutomirski [Fri, 6 Mar 2015 03:19:05 +0000 (19:19 -0800)]
x86/asm/entry: Rename 'init_tss' to 'cpu_tss'

It has nothing to do with init -- there's only one TSS per cpu.

Other names considered include:

 - current_tss: Confusing because we never switch the tss.
 - singleton_tss: Too long.

This patch was generated with 's/init_tss/cpu_tss/g'.  Followup
patches will fix INIT_TSS and INIT_TSS_IST by hand.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/da29fb2a793e4f649d93ce2d1ed320ebe8516262.1425611534.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64/compat: Change the 32-bit sysenter code to use sp0
Andy Lutomirski [Fri, 6 Mar 2015 03:19:04 +0000 (19:19 -0800)]
x86/asm/entry/64/compat: Change the 32-bit sysenter code to use sp0

The ia32 sysenter code loaded the top of the kernel stack into
rsp by loading kernel_stack and then adjusting it.  It can be
simplified to just read sp0 directly.

This requires the addition of a new asm-offsets entry for sp0.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/88ff9006163d296a0665338585c36d9bfb85235d.1425611534.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry: Switch all C consumers of kernel_stack to this_cpu_sp0()
Andy Lutomirski [Fri, 6 Mar 2015 03:19:03 +0000 (19:19 -0800)]
x86/asm/entry: Switch all C consumers of kernel_stack to this_cpu_sp0()

This will make modifying the semantics of kernel_stack easier.

The change to ist_begin_non_atomic() is necessary because sp0 no
longer points to the same THREAD_SIZE-aligned region as RSP;
it's one byte too high for that.  At Denys' suggestion, rather
than offsetting it, just check explicitly that we're in the
correct range ending at sp0.  This has the added benefit that we
no longer assume that the thread stack is aligned to
THREAD_SIZE.

Suggested-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/ef8254ad414cbb8034c9a56396eeb24f5dd5b0de.1425611534.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry: Add this_cpu_sp0() to read sp0 for the current cpu
Andy Lutomirski [Fri, 6 Mar 2015 03:19:02 +0000 (19:19 -0800)]
x86/asm/entry: Add this_cpu_sp0() to read sp0 for the current cpu

We currently store references to the top of the kernel stack in
multiple places: kernel_stack (with an offset) and
init_tss.x86_tss.sp0 (no offset).  The latter is defined by
hardware and is a clean canonical way to find the top of the
stack.  Add an accessor so we can start using it.

This needs minor paravirt tweaks.  On native, sp0 defines the
top of the kernel stack and is therefore always correct.  On Xen
and lguest, the hypervisor tracks the top of the stack, but we
want to start reading sp0 in the kernel.  Fixing this is simple:
just update our local copy of sp0 as well as the hypervisor's
copy on task switches.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/8d675581859712bee09a055ed8f785d80dac1eca.1425611534.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/traps: Separate set_intr_gate() and clean up early_trap_init()
Wang Nan [Fri, 27 Feb 2015 04:19:49 +0000 (12:19 +0800)]
x86/traps: Separate set_intr_gate() and clean up early_trap_init()

As early_trap_init() doesn't use IST, replace
set_intr_gate_ist() and set_system_intr_gate_ist() with their
standard counterparts.

set_intr_gate() requires a trace_debug symbol which we don't
have and won't use. This patch separates set_intr_gate() into two
parts, and uses base version in early_trap_init().

Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: <dave.hansen@linux.intel.com>
Cc: <lizefan@huawei.com>
Cc: <masami.hiramatsu.pt@hitachi.com>
Cc: <oleg@redhat.com>
Cc: <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1425010789-13714-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Remove a bogus 'ret_from_fork' optimization
Andy Lutomirski [Thu, 26 Feb 2015 22:40:39 +0000 (14:40 -0800)]
x86/asm/entry/64: Remove a bogus 'ret_from_fork' optimization

'ret_from_fork' checks TIF_IA32 to determine whether 'pt_regs' and
the related state make sense for 'ret_from_sys_call'.  This is
entirely the wrong check.  TS_COMPAT would make a little more
sense, but there's really no point in keeping this optimization
at all.

This fixes a return to the wrong user CS if we came from int
0x80 in a 64-bit task.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/4710be56d76ef994ddf59087aad98c000fbab9a4.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Simplify optimistic SYSRET
Denys Vlasenko [Thu, 26 Feb 2015 22:40:38 +0000 (14:40 -0800)]
x86/asm/entry/64: Simplify optimistic SYSRET

Avoid redundant load of %r11 (it is already loaded a few
instructions before).

Also simplify %rsp restoration, instead of two steps:

         add $0x80, %rsp
         mov 0x18(%rsp), %rsp

we can do a simplified single step to restore user-space RSP:

         mov 0x98(%rsp), %rsp

and get the same result.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
[ Clarified the changelog. ]
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1aef69b346a6db0d99cdfb0f5ba83e8c985e27d7.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64/compat: Use more readable constant
Denys Vlasenko [Thu, 26 Feb 2015 22:40:37 +0000 (14:40 -0800)]
x86/asm/entry/64/compat: Use more readable constant

The last instance of "mysterious" SS+8 constant is replaced by
SIZEOF_PTREGS.

Message-Id: <1424822419-10267-1-git-send-email-dvlasenk@redhat.com>
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/d35aeba3059407ac54f472ddcfbea767ff8916ac.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Use more readable constants
Denys Vlasenko [Thu, 26 Feb 2015 22:40:36 +0000 (14:40 -0800)]
x86/asm/entry/64: Use more readable constants

Constants such as SS+8 or SS+8-RIP are mysterious.
In most cases, SS+8 is just meant to be SIZEOF_PTREGS,
SS+8-RIP is RIP's offset in the iret frame.

This patch changes some of these constants to be less
mysterious.

No code changes (verified with objdump).

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1d20491384773bd606e23a382fac23ddb49b5178.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64/compat: Fold the IA32_ARG_FIXUP macro into its callers
Denys Vlasenko [Thu, 26 Feb 2015 22:40:35 +0000 (14:40 -0800)]
x86/asm/entry/64/compat: Fold the IA32_ARG_FIXUP macro into its callers

Use of a small macro - one with conditional expansion - does
more harm than good. It obfuscates code, with minimal code
reuse.

For example, because of obfuscation it's not obvious that
in 'ia32_sysenter_target', we can optimize loading of r9 -
currently it is loaded with a detour through ebp.

This patch folds the IA32_ARG_FIXUP macro into its callers.

No code changes.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/4da092094cd78734384ac31e0d4ec1d8f69145a2.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Clean up and document various entry code details
Denys Vlasenko [Thu, 26 Feb 2015 22:40:34 +0000 (14:40 -0800)]
x86/asm/entry/64: Clean up and document various entry code details

This patch does a lot of cleanup in comments and formatting,
but it does not change any code:

 - Rename 'save_paranoid' to 'paranoid_entry': this makes naming
   similar to its "non-paranoid" sibling, 'error_entry',
   and to its counterpart, 'paranoid_exit'.

 - Use the same CFI annotation atop 'paranoid_entry' and 'error_entry'.

 - Fix irregular indentation of assembler operands.

 - Add/fix comments on top of 'paranoid_entry' and 'error_entry'.

 - Remove stale comment about "oldrax".

 - Make comments about "no swapgs" flag in ebx more prominent.

 - Deindent wrongly indented top-level comment atop 'paranoid_exit'.

 - Indent wrongly deindented comment inside 'error_entry'.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/4640f9fcd5ea46eb299b1cd6d3f5da3167d2f78d.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Move 'save_paranoid' and 'ret_from_fork' closer to their users
Denys Vlasenko [Thu, 26 Feb 2015 22:40:33 +0000 (14:40 -0800)]
x86/asm/entry/64: Move 'save_paranoid' and 'ret_from_fork' closer to their users

For some odd reason, these two functions are at the very top of
the file. "save_paranoid"'s caller is approximately in the middle
of it, move it there. Move 'ret_from_fork' to be right after
fork/exec helpers.

This is a pure block move, nothing is changed in the function
bodies.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/6446bbfe4094532623a5b83779b7015fec167a9d.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry: Add comments about various syscall instructions
Denys Vlasenko [Thu, 26 Feb 2015 22:40:32 +0000 (14:40 -0800)]
x86/asm/entry: Add comments about various syscall instructions

SYSCALL/SYSRET and SYSENTER/SYSEXIT have weird semantics.
Moreover, they differ in 32- and 64-bit mode.

What is saved? What is not? Is rsp set? Are interrupts disabled?
People tend to not remember these details well enough.

This patch adds comments which explain in detail
what registers are modified by each of these instructions.

The comments are placed immediately before corresponding
entry and exit points.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/a94b98b63527797c871a81402ff5060b18fa880a.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Remove 'int_check_syscall_exit_work'
Andy Lutomirski [Thu, 26 Feb 2015 22:40:31 +0000 (14:40 -0800)]
x86/asm/entry/64: Remove 'int_check_syscall_exit_work'

Nothing references it anymore.

Reported-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 96b6352c1271 ("x86_64, entry: Remove the syscall exit audit and schedule optimizations")
Link: http://lkml.kernel.org/r/dd2a4d26ecc7a5db61b476727175cd99ae2b32a4.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry: Do mass removal of 'ARGOFFSET'
Denys Vlasenko [Thu, 26 Feb 2015 22:40:30 +0000 (14:40 -0800)]
x86/asm/entry: Do mass removal of 'ARGOFFSET'

ARGOFFSET is zero now, removing it changes no code.

A few macros lost "offset" parameter, since it is always zero
now too.

No code changes - verified with objdump.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/8689f937622d9d2db0ab8be82331fa15e4ed4713.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Shrink code in 'paranoid_exit'
Denys Vlasenko [Thu, 26 Feb 2015 22:40:29 +0000 (14:40 -0800)]
x86/asm/entry/64: Shrink code in 'paranoid_exit'

RESTORE_EXTRA_REGS + RESTORE_C_REGS looks small, but it's
a lot of instructions (fourteen). Let's reuse them.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
[ Cleaned up the labels. ]
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1421272101-16847-2-git-send-email-dvlasenk@redhat.com
Link: http://lkml.kernel.org/r/59d71848cee3ec9eb48c0252e602efd6bd560e3c.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Fix comments
Denys Vlasenko [Thu, 26 Feb 2015 22:40:28 +0000 (14:40 -0800)]
x86/asm/entry/64: Fix comments

 - Misleading and slightly incorrect comments in "struct pt_regs" are
   fixed (four instances).

 - Fix incorrect comment atop EMPTY_FRAME macro.

 - Explain in more detail what we do with stack layout during hw interrupt.

 - Correct comments about "partial stack frame" which are no longer
   true.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1423778052-21038-3-git-send-email-dvlasenk@redhat.com
Link: http://lkml.kernel.org/r/e1f4429c491fe6ceeddb879dea2786e0f8920f9c.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Always allocate a complete "struct pt_regs" on the kernel stack
Denys Vlasenko [Thu, 26 Feb 2015 22:40:27 +0000 (14:40 -0800)]
x86/asm/entry/64: Always allocate a complete "struct pt_regs" on the kernel stack

The 64-bit entry code was using six stack slots less by not
saving/restoring registers which are callee-preserved according
to the C ABI, and was not allocating space for them.

Only when syscalls needed a complete "struct pt_regs" was
the complete area allocated and filled in.

As an additional twist, on interrupt entry a "slightly less
truncated pt_regs" trick is used, to make nested interrupt
stacks easier to unwind.

This proved to be a source of significant obfuscation and subtle
bugs. For example, 'stub_fork' had to pop the return address,
extend the struct, save registers, and push return address back.
Ugly. 'ia32_ptregs_common' pops return address and "returns" via
jmp insn, throwing a wrench into CPU return stack cache.

This patch changes the code to always allocate a complete
"struct pt_regs" on the kernel stack. The saving of registers
is still done lazily.

"Partial pt_regs" trick on interrupt stack is retained.

Macros which manipulate "struct pt_regs" on stack are reworked:

 - ALLOC_PT_GPREGS_ON_STACK allocates the structure.

 - SAVE_C_REGS saves to it those registers which are clobbered
   by C code.

 - SAVE_EXTRA_REGS saves to it all other registers.

 - Corresponding RESTORE_* and REMOVE_PT_GPREGS_FROM_STACK macros
   reverse it.

'ia32_ptregs_common', 'stub_fork' and friends lost their ugly dance
with the return pointer.

LOAD_ARGS32 in ia32entry.S now uses symbolic stack offsets
instead of magic numbers.

'error_entry' and 'save_paranoid' now use SAVE_C_REGS +
SAVE_EXTRA_REGS instead of having it open-coded yet again.

Patch was run-tested: 64-bit executables, 32-bit executables,
strace works.

Timing tests did not show measurable difference in 32-bit
and 64-bit syscalls.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1423778052-21038-2-git-send-email-dvlasenk@redhat.com
Link: http://lkml.kernel.org/r/b89763d354aa23e670b9bdf3a40ae320320a7c2e.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/entry/64: Fix incorrect symbolic constant usage: R11->ARGOFFSET
Denys Vlasenko [Thu, 26 Feb 2015 22:40:26 +0000 (14:40 -0800)]
x86/asm/entry/64: Fix incorrect symbolic constant usage: R11->ARGOFFSET

Since the last fix of this nature, a few more instances have crept
in. Fix them up. No object code changes (constants have the same
value).

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1423778052-21038-1-git-send-email-dvlasenk@redhat.com
Link: http://lkml.kernel.org/r/f5e1c4084319a42e5f14d41e2d638949ce66bc08.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm: Introduce push/pop macros which generate CFI_REL_OFFSET and CFI_RESTORE
Denys Vlasenko [Thu, 26 Feb 2015 22:40:25 +0000 (14:40 -0800)]
x86/asm: Introduce push/pop macros which generate CFI_REL_OFFSET and CFI_RESTORE

Sequences:

        pushl_cfi %reg
        CFI_REL_OFFSET reg, 0

and:

        popl_cfi %reg
        CFI_RESTORE reg

happen quite often. This patch adds macros which generate them.

No assembly changes (verified with objdump -dr vmlinux.o).

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1421017655-25561-1-git-send-email-dvlasenk@redhat.com
Link: http://lkml.kernel.org/r/2202eb90f175cf45d1b2d1c64dbb5676a8ad07ad.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/asm/64: Open-code register save/restore in trace_hardirqs*() thunks
Denys Vlasenko [Thu, 26 Feb 2015 22:40:24 +0000 (14:40 -0800)]
x86/asm/64: Open-code register save/restore in trace_hardirqs*() thunks

This is a preparatory patch for change in "struct pt_regs"
handling in entry_64.S.

trace_hardirqs*() thunks were (ab)using a part of the
'pt_regs' handling code, namely the SAVE_ARGS/RESTORE_ARGS
macros, to save/restore registers across C function calls.

Since SAVE_ARGS is going to be changed, open-code
register saving/restoring here.

Incidentally, this removes a bit of dead code:
one SAVE_ARGS was used just to emit a CFI annotation,
but it also generated unreachable assembly instructions.

Take a page from thunk_32.S and use push/pop instructions
instead of movq, they are far shorter:
1 or 2 bytes versus 5, and no need for instructions to adjust %rsp:

   text    data     bss     dec     hex filename
    333      40       0     373     175 thunk_64_movq.o
    104      40       0     144      90 thunk_64_push_pop.o

[ This is ugly as sin, but we'll fix up the ugliness in the next
  patch. I see no point in reordering patches just to avoid an
  ugly intermediate state.  --Andy ]

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1420927210-19738-4-git-send-email-dvlasenk@redhat.com
Link: http://lkml.kernel.org/r/4c979ad604f0f02c5ade3b3da308b53eabd5e198.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agoMerge tag 'alternatives_padding' of git://git.kernel.org/pub/scm/linux/kernel/git...
Ingo Molnar [Wed, 4 Mar 2015 05:33:49 +0000 (06:33 +0100)]
Merge tag 'alternatives_padding' of git://git./linux/kernel/git/bp/bp into x86/asm

Pull alternative instructions framework improvements from Borislav Petkov:

 "A more involved rework of the alternatives framework to be able to
  pad instructions and thus make using the alternatives macros more
  straightforward and without having to figure out old and new instruction
  sizes but have the toolchain figure that out for us.

  Furthermore, it optimizes JMPs used so that fetch and decode can be
  relieved with smaller versions of the JMPs, where possible.

  Some stats:

    x86_64 defconfig:

    Alternatives sites total:               2478
    Total padding added (in Bytes):         6051

  The padding is currently done for:

    X86_FEATURE_ALWAYS
    X86_FEATURE_ERMS
    X86_FEATURE_LFENCE_RDTSC
    X86_FEATURE_MFENCE_RDTSC
    X86_FEATURE_SMAP

  This is with the latest version of the patchset. Of course, on each
  machine the alternatives sites actually being patched are a proper
  subset of the total number."

Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agoMerge tag 'v4.0-rc2' into x86/asm, to refresh the tree
Ingo Molnar [Wed, 4 Mar 2015 05:35:43 +0000 (06:35 +0100)]
Merge tag 'v4.0-rc2' into x86/asm, to refresh the tree

Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/compat: Remove sys32_vm86_warning
Brian Gerst [Wed, 4 Mar 2015 03:31:34 +0000 (22:31 -0500)]
x86/compat: Remove sys32_vm86_warning

The check against lastcomm is racy, and the message it produces
isn't necessary.  vm86 support can be disabled on a 32-bit
kernel also, and doesn't have this message.  Switch to
sys_ni_syscall instead.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1425439896-8322-4-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/compat: Merge native and compat 32-bit syscall tables
Brian Gerst [Wed, 4 Mar 2015 03:31:33 +0000 (22:31 -0500)]
x86/compat: Merge native and compat 32-bit syscall tables

Combine the 32-bit syscall tables into one file.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1425439896-8322-3-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agox86/compat: Remove compat_ni_syscall()
Brian Gerst [Wed, 4 Mar 2015 03:31:32 +0000 (22:31 -0500)]
x86/compat: Remove compat_ni_syscall()

compat_ni_syscall() does the same thing as sys_ni_syscall().

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1425439896-8322-2-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agoLinux 4.0-rc2
Linus Torvalds [Tue, 3 Mar 2015 17:04:59 +0000 (09:04 -0800)]
Linux 4.0-rc2

9 years agodrm/i915: Fix modeset state confusion in the load detect code
Daniel Vetter [Tue, 3 Mar 2015 16:31:21 +0000 (17:31 +0100)]
drm/i915: Fix modeset state confusion in the load detect code

This is a tricky story of the new atomic state handling and the legacy
code fighting over each another. The bug at hand is an underrun of the
framebuffer reference with subsequent hilarity caused by the load
detect code. Which is peculiar since the the exact same code works
fine as the implementation of the legacy setcrtc ioctl.

Let's look at the ingredients:

- Currently our code is a crazy mix of legacy modeset interfaces to
  set the parameters and half-baked atomic state tracking underneath.
  While this transition is going we're using the transitional plane
  helpers to update the atomic side (drm_plane_helper_disable/update
  and friends), i.e. plane->state->fb. Since the state structure owns
  the fb those functions take care of that themselves.

  The legacy state (specifically crtc->primary->fb) is still managed
  by the old code (and mostly by the drm core), with the fb reference
  counting done by callers (core drm for the ioctl or the i915 load
  detect code). The relevant commit is

  commit ea2c67bb4affa84080c616920f3899f123786e56
  Author: Matt Roper <matthew.d.roper@intel.com>
  Date:   Tue Dec 23 10:41:52 2014 -0800

      drm/i915: Move to atomic plane helpers (v9)

- drm_plane_helper_disable has special code to handle multiple calls
  in a row - it checks plane->crtc == NULL and bails out. This is to
  match the proper atomic implementation which needs the crtc to get
  at the implied locking context atomic updates always need. See

  commit acf24a395c5a9290189b080383564437101d411c
  Author: Daniel Vetter <daniel.vetter@ffwll.ch>
  Date:   Tue Jul 29 15:33:05 2014 +0200

      drm/plane-helper: transitional atomic plane helpers

- The universal plane code split out the implicit primary plane from
  the CRTC into it's own full-blown drm_plane object. As part of that
  the setcrtc ioctl (which updated both the crtc mode and primary
  plane) learned to set crtc->primary->crtc on modeset to make sure
  the plane->crtc assignments statate up to date in

  commit e13161af80c185ecd8dc4641d0f5df58f9e3e0af
  Author: Matt Roper <matthew.d.roper@intel.com>
  Date:   Tue Apr 1 15:22:38 2014 -0700

      drm: Add drm_crtc_init_with_planes() (v2)

  Unfortunately we've forgotten to update the load detect code. Which
  wasn't a problem since the load detect modeset is temporary and
  always undone before we drop the locks.

- Finally there is a organically grown history (i.e. don't ask) around
  who sets the legacy plane->fb for the various driver entry points.
  Originally updating that was the drivers duty, but for almost all
  places we've moved that (plus updating the refcounts) into the core.
  Again the exception is the load detect code.

Taking all together the following happens:
- The load detect code doesn't set crtc->primary->crtc. This is only
  really an issue on crtcs never before used or when userspace
  explicitly disabled the primary plane.

- The plane helper glue code short-circuits because of that and leaves
  a non-NULL fb behind in plane->state->fb and plane->fb. The state
  fb isn't a real problem (it's properly refcounted on its own), it's
  just the canary.

- Load detect code drops the reference for that fb, but doesn't set
  plane->fb = NULL. This is ok since it's still living in that old
  world where drivers had to clear the pointer but the core/callers
  handled the refcounting.

- On the next modeset the drm core notices plane->fb and takes care of
  refcounting it properly by doing another unref. This drops the
  refcount to zero, leaving state->plane now pointing at freed memory.

- intel_plane_duplicate_state still assume it owns a reference to that
  very state->fb and bad things start to happen.

Fix this all by applying the same duct-tape as for the legacy setcrtc
ioctl code and set crtc->primary->crtc properly.

Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Paulo Zanoni <przanoni@gmail.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Matt Roper <matthew.d.roper@intel.com>
Reported-and-tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agoperf/bench: Add -r all so that you can run all mem* routines
Borislav Petkov [Thu, 26 Feb 2015 18:02:43 +0000 (19:02 +0100)]
perf/bench: Add -r all so that you can run all mem* routines

perf bench mem mem{set,cpy} -r all thus runs all available mem
benchmarking routines.

Reviewed-by: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Signed-off-by: Borislav Petkov <bp@suse.de>
9 years agoperf/bench: Carve out mem routine benchmarking
Borislav Petkov [Thu, 26 Feb 2015 17:51:37 +0000 (18:51 +0100)]
perf/bench: Carve out mem routine benchmarking

... so that we can call it multiple times. See next patch.

Reviewed-by: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Signed-off-by: Borislav Petkov <bp@suse.de>
9 years agoperf/bench: Fix mem* routines usage after alternatives change
Borislav Petkov [Thu, 26 Feb 2015 17:38:16 +0000 (18:38 +0100)]
perf/bench: Fix mem* routines usage after alternatives change

Adjust perf bench to the new changes in the alternatives code for
memcpy/memset.

Reviewed-by: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Signed-off-by: Borislav Petkov <bp@suse.de>
9 years agoMerge tag 'gpio-v4.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux...
Linus Torvalds [Mon, 2 Mar 2015 22:13:39 +0000 (14:13 -0800)]
Merge tag 'gpio-v4.0-2' of git://git./linux/kernel/git/linusw/linux-gpio

Pull GPIO fixes from Linus Walleij:
 "Two GPIO fixes:

   - Fix a translation problem in of_get_named_gpiod_flags()

   - Fix a long standing container_of() mistake in the TPS65912 driver"

* tag 'gpio-v4.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: tps65912: fix wrong container_of arguments
  gpiolib: of: allow of_gpiochip_find_and_xlate to find more than one chip per node

9 years agoMerge branch 'fixes-for-4.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Mon, 2 Mar 2015 22:08:10 +0000 (14:08 -0800)]
Merge branch 'fixes-for-4.0-rc2' of git://git./linux/kernel/git/evalenti/linux-soc-thermal

Pull thermal management fixes from Eduardo Valentin:
 "Specifics:

   - Several fixes in tmon tool.

   - Fixes in intel int340x for _ART and _TRT tables.

   - Add id for Avoton SoC into powerclamp driver.

   - Fixes in RCAR thermal driver to remove race conditions and fix fail
     path

   - Fixes in TI thermal driver: removal of unnecessary code and build
     fix if !CONFIG_PM_SLEEP

   - Cleanups in exynos thermal driver

   - Add stubs for include/linux/thermal.h.  Now drivers using thermal
     calls but that also work without CONFIG_THERMAL will be able to
     compile for systems that don't care about thermal.

  Note: I am sending this pull on Rui's behalf while he fixes issues in
  his Linux box"

* 'fixes-for-4.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal:
  thermal: int340x_thermal: Ignore missing _ART, _TRT tables
  thermal/intel_powerclamp: add id for Avoton SoC
  tools/thermal: tmon: silence 'set but not used' warnings
  tools/thermal: tmon: use pkg-config to determine library dependencies
  tools/thermal: tmon: support cross-compiling
  tools/thermal: tmon: add .gitignore
  tools/thermal: tmon: fixup tui windowing calculations
  tools/thermal: tmon: tui: don't hard-code dialog window size assumptions
  tools/thermal: tmon: add min/max macros
  tools/thermal: tmon: add --target-temp parameter
  thermal: exynos: Clean-up code to use oneline entry for exynos compatible table
  thermal: rcar: Make error and remove paths symmetrical with init
  thermal: rcar: Fix race condition between init and interrupt
  thermal: Introduce dummy functions when thermal is not defined
  ti-soc-thermal: Delete an unnecessary check before the function call "cpufreq_cooling_unregister"
  thermal: ti-soc-thermal: bandgap: Fix build warning if !CONFIG_PM_SLEEP

9 years agoMerge tag 'md/4.0-fixes' of git://neil.brown.name/md
Linus Torvalds [Mon, 2 Mar 2015 22:03:27 +0000 (14:03 -0800)]
Merge tag 'md/4.0-fixes' of git://neil.brown.name/md

Pull md fixes from Neil Brown:
 "Three md fixes:

   - fix a read-balance problem that was reported 2 years ago, but that
     I never noticed the report :-(

   - fix for rare RAID6 problem causing incorrect bitmap updates when
     two devices fail.

   - add __ATTR_PREALLOC annotation now that it is possible"

* tag 'md/4.0-fixes' of git://neil.brown.name/md:
  md: mark some attributes as pre-alloc
  raid5: check faulty flag for array status during recovery.
  md/raid1: fix read balance when a drive is write-mostly.

9 years agoMerge tag 'metag-fixes-v4.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jhoga...
Linus Torvalds [Mon, 2 Mar 2015 22:02:17 +0000 (14:02 -0800)]
Merge tag 'metag-fixes-v4.0-1' of git://git./linux/kernel/git/jhogan/metag

Pull arch/metag fix from James Hogan:
 "This is just a single patch to fix the KSTK_EIP() and KSTK_ESP()
  macros for metag which have always been erronously returning the PC
  and stack pointer of the task's kernel context rather than from its
  user context saved at entry from userland into the kernel, which
  affects the contents of /proc/<pid>/maps and /proc/<pid>/stat"

* tag 'metag-fixes-v4.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag:
  metag: Fix KSTK_EIP() and KSTK_ESP() macros

9 years agoMerge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 1 Mar 2015 20:22:44 +0000 (12:22 -0800)]
Merge branch 'x86-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull x86 fixes from Ingo Molnar:
 "A CR4-shadow 32-bit init fix, plus two typo fixes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Init per-cpu shadow copy of CR4 on 32-bit CPUs too
  x86/platform/intel-mid: Fix trivial printk message typo in intel_mid_arch_setup()
  x86/cpu/intel: Fix trivial typo in intel_tlb_table[]

9 years agoMerge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 1 Mar 2015 20:00:25 +0000 (12:00 -0800)]
Merge branch 'timers-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull timer fixes from Ingo Molnar:
 "Three clockevents/clocksource driver fixes"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: pxa: Fix section mismatch
  clocksource: mtk: Fix race conditions in probe code
  clockevents: asm9260: Fix compilation error with sparc/sparc64 allyesconfig

9 years agoMerge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 1 Mar 2015 19:56:13 +0000 (11:56 -0800)]
Merge branch 'perf-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull perf fixes from Ingo Molnar:
 "Two kprobes fixes and a handful of tooling fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf tools: Make sparc64 arch point to sparc
  perf symbols: Define EM_AARCH64 for older OSes
  perf top: Fix SIGBUS on sparc64
  perf tools: Fix probing for PERF_FLAG_FD_CLOEXEC flag
  perf tools: Fix pthread_attr_setaffinity_np build error
  perf tools: Define _GNU_SOURCE on pthread_attr_setaffinity_np feature check
  perf bench: Fix order of arguments to memcpy_alloc_mem
  kprobes/x86: Check for invalid ftrace location in __recover_probed_insn()
  kprobes/x86: Use 5-byte NOP when the code might be modified by ftrace

9 years agoMerge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 1 Mar 2015 19:27:04 +0000 (11:27 -0800)]
Merge branch 'locking-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull locking fix from Ingo Molnar:
 "An rtmutex deadlock path fixlet"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/rtmutex: Set state back to running on error

9 years agoMerge tag 'perf-urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git...
Ingo Molnar [Sun, 1 Mar 2015 16:41:42 +0000 (17:41 +0100)]
Merge tag 'perf-urgent-for-mingo' of git://git./linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

  - pthread_attr_setaffinity_np() feature detection build fixes (Adrian Hunter, Josh Boyer)

  - Fix probing for PERF_FLAG_FD_CLOEXEC flag (Adrian Hunter)

  - Fix order of arguments to memcpy_alloc_mem in 'perf bench' (Bruce Merry)

  - Sparc64 and Aarch64 build and segfault fixes (David Ahern)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agolocking/rtmutex: Set state back to running on error
Sebastian Andrzej Siewior [Fri, 27 Feb 2015 16:57:09 +0000 (17:57 +0100)]
locking/rtmutex: Set state back to running on error

The "usual" path is:

 - rt_mutex_slowlock()
 - set_current_state()
 - task_blocks_on_rt_mutex() (ret 0)
 - __rt_mutex_slowlock()
   - sleep or not but do return with __set_current_state(TASK_RUNNING)
 - back to caller.

In the early error case where task_blocks_on_rt_mutex() return
-EDEADLK we never change the task's state back to RUNNING. I
assume this is intended. Without this change after ww_mutex
using rt_mutex the selftest passes but later I get plenty of:

  | bad: scheduling from the idle thread!

backtraces.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: afffc6c1805d ("locking/rtmutex: Optimize setting task running after being blocked")
Link: http://lkml.kernel.org/r/1425056229-22326-4-git-send-email-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agoMerge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Linus Torvalds [Sat, 28 Feb 2015 18:36:48 +0000 (10:36 -0800)]
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux

Pull drm fixes from Dave Airlie:
 "Just general fixes: radeon, i915, atmel, tegra, amdkfd and one core
  fix"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (28 commits)
  drm: atmel-hlcdc: remove clock polarity from crtc driver
  drm/radeon: only enable DP audio if the monitor supports it
  drm/radeon: fix atom aux payload size check for writes (v2)
  drm/radeon: fix 1 RB harvest config setup for TN/RL
  drm/radeon: enable SRBM timeout interrupt on EG/NI
  drm/radeon: enable SRBM timeout interrupt on SI
  drm/radeon: enable SRBM timeout interrupt on CIK v2
  drm/radeon: dump full IB if we hit a packet error
  drm/radeon: disable mclk switching with 120hz+ monitors
  drm/radeon: use drm_mode_vrefresh() rather than mode->vrefresh
  drm/radeon: enable native backlight control on old macs
  drm/i915: Fix frontbuffer false positve.
  drm/i915: Align initial plane backing objects correctly
  drm/i915: avoid processing spurious/shared interrupts in low-power states
  drm/i915: Check obj->vma_list under the struct_mutex
  drm/i915: Fix a use after free, and unbalanced refcounting
  drm: atmel-hlcdc: remove useless pm_runtime_put_sync in probe
  drm: atmel-hlcdc: reset layer A2Q and UPDATE bits when disabling it
  drm: Fix deadlock due to getconnector locking changes
  drm/i915: Dell Chromebook 11 has PWM backlight
  ...

9 years agoMerge branch 'for-linus' of git://git.kernel.dk/linux-block
Linus Torvalds [Sat, 28 Feb 2015 18:21:57 +0000 (10:21 -0800)]
Merge branch 'for-linus' of git://git.kernel.dk/linux-block

Pull block layer fixes from Jens Axboe:
 "Two smaller fixes for this cycle:

   - A fixup from Keith so that NVMe compiles without BLK_INTEGRITY,
     basically just moving the code around appropriately.

   - A fixup for shm, fixing an oops in shmem_mapping() for mapping with
     no inode.  From Sasha"

[ The shmem fix doesn't look block-layer-related, but fixes a bug that
  happened due to the backing_dev_info removal..  - Linus ]

* 'for-linus' of git://git.kernel.dk/linux-block:
  mm: shmem: check for mapping owner before dereferencing
  NVMe: Fix for BLK_DEV_INTEGRITY not set

9 years agoMerge tag 'xfs-for-linus-4.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sat, 28 Feb 2015 18:06:33 +0000 (10:06 -0800)]
Merge tag 'xfs-for-linus-4.0-rc2' of git://git./linux/kernel/git/dgc/linux-xfs

Pull xfs fixes from Dave Chinner:
 "These are fixes for regressions/bugs introduced in the 4.0 merge cycle
  and problems discovered during the merge window that need to be pushed
  back to stable kernels ASAP.

  This contains:
   - ensure quota type is reset in on-disk dquots
   - fix missing partial EOF block data flush on truncate extension
   - fix transaction leak in error handling for new pnfs block layout
     support
   - add missing target_ip check to RENAME_EXCHANGE"

* tag 'xfs-for-linus-4.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs:
  xfs: cancel failed transaction in xfs_fs_commit_blocks()
  xfs: Ensure we have target_ip for RENAME_EXCHANGE
  xfs: ensure truncate forces zeroed blocks to disk
  xfs: Fix quota type in quota structures when reusing quota file

9 years agoMerge branch 'akpm' (patches from Andrew)
Linus Torvalds [Sat, 28 Feb 2015 17:58:03 +0000 (09:58 -0800)]
Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "13 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm: add missing __PAGETABLE_{PUD,PMD}_FOLDED defines
  mm: page_alloc: revert inadvertent !__GFP_FS retry behavior change
  kernel/sys.c: fix UNAME26 for 4.0
  mm: memcontrol: use "max" instead of "infinity" in control knobs
  zram: use proper type to update max_used_pages
  drivers/rtc/rtc-ds1685.c: fix conditional in ds1685_rtc_sysfs_time_regs_{show,store}
  nilfs2: fix potential memory overrun on inode
  scripts/gdb: add empty package initialization script
  rtc: ds1685: remove superfluous checks for out-of-range u8 values
  rtc: ds1685: fix ds1685_rtc_alarm_irq_enable build error
  memcg: fix low limit calculation
  mm/nommu: fix memory leak
  ocfs2: update web page + git tree in documentation

9 years agomm: add missing __PAGETABLE_{PUD,PMD}_FOLDED defines
Kirill A. Shutemov [Fri, 27 Feb 2015 23:52:12 +0000 (15:52 -0800)]
mm: add missing __PAGETABLE_{PUD,PMD}_FOLDED defines

Core mm expects __PAGETABLE_{PUD,PMD}_FOLDED to be defined if these page
table levels folded.  Usually, these defines are provided by
<asm-generic/pgtable-nopmd.h> and <asm-generic/pgtable-nopud.h>.

But some architectures fold page table levels in a custom way.  They
need to define these macros themself.  This patch adds missing defines.

The patch fixes mm->nr_pmds underflow and eliminates dead __pmd_alloc()
and __pud_alloc() on architectures without these page table levels.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agomm: page_alloc: revert inadvertent !__GFP_FS retry behavior change
Johannes Weiner [Fri, 27 Feb 2015 23:52:09 +0000 (15:52 -0800)]
mm: page_alloc: revert inadvertent !__GFP_FS retry behavior change

Historically, !__GFP_FS allocations were not allowed to invoke the OOM
killer once reclaim had failed, but nevertheless kept looping in the
allocator.

Commit 9879de7373fc ("mm: page_alloc: embed OOM killing naturally into
allocation slowpath"), which should have been a simple cleanup patch,
accidentally changed the behavior to aborting the allocation at that
point.  This creates problems with filesystem callers (?) that currently
rely on the allocator waiting for other tasks to intervene.

Revert the behavior as it shouldn't have been changed as part of a
cleanup patch.

Fixes: 9879de7373fc ("mm: page_alloc: embed OOM killing naturally into allocation slowpath")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Dave Chinner <david@fromorbit.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: <stable@vger.kernel.org> [3.19.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agokernel/sys.c: fix UNAME26 for 4.0
Jon DeVree [Fri, 27 Feb 2015 23:52:07 +0000 (15:52 -0800)]
kernel/sys.c: fix UNAME26 for 4.0

There's a uname workaround for broken userspace which can't handle kernel
versions of 3.x.  Update it for 4.x.

Signed-off-by: Jon DeVree <nuxi@vault24.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agomm: memcontrol: use "max" instead of "infinity" in control knobs
Johannes Weiner [Fri, 27 Feb 2015 23:52:04 +0000 (15:52 -0800)]
mm: memcontrol: use "max" instead of "infinity" in control knobs

The memcg control knobs indicate the highest possible value using the
symbolic name "infinity", which is long and awkward to type.

Switch to the string "max", which is just as descriptive but shorter and
sweeter.

This changes a user interface, so do it before the release and before
the development flag is dropped from the default hierarchy.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agozram: use proper type to update max_used_pages
Joonsoo Kim [Fri, 27 Feb 2015 23:52:01 +0000 (15:52 -0800)]
zram: use proper type to update max_used_pages

max_used_pages is defined as atomic_long_t so we need to use unsigned
long to keep temporary value for it rather than int which is smaller
than unsigned long in a 64 bit system.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agodrivers/rtc/rtc-ds1685.c: fix conditional in ds1685_rtc_sysfs_time_regs_{show,store}
Joshua Kinard [Fri, 27 Feb 2015 23:51:59 +0000 (15:51 -0800)]
drivers/rtc/rtc-ds1685.c: fix conditional in ds1685_rtc_sysfs_time_regs_{show,store}

Fix a conditional statement checking for NULL in both
ds1685_rtc_sysfs_time_regs_show and ds1685_rtc_sysfs_time_regs_store
that was using a logical AND when it should be using a logical OR so
that we fail out of the function properly if the condition ever
evaluates to true.

Fixes: aaaf5fbf56f1 ("rtc: add driver for DS1685 family of real time clocks")
Signed-off-by: Joshua Kinard <kumba@gentoo.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agonilfs2: fix potential memory overrun on inode
Ryusuke Konishi [Fri, 27 Feb 2015 23:51:56 +0000 (15:51 -0800)]
nilfs2: fix potential memory overrun on inode

Each inode of nilfs2 stores a root node of a b-tree, and it turned out to
have a memory overrun issue:

Each b-tree node of nilfs2 stores a set of key-value pairs and the number
of them (in "bn_nchildren" member of nilfs_btree_node struct), as well as
a few other "bn_*" members.

Since the value of "bn_nchildren" is used for operations on the key-values
within the b-tree node, it can cause memory access overrun if a large
number is incorrectly set to "bn_nchildren".

For instance, nilfs_btree_node_lookup() function determines the range of
binary search with it, and too large "bn_nchildren" leads
nilfs_btree_node_get_key() in that function to overrun.

As for intermediate b-tree nodes, this is prevented by a sanity check
performed when each node is read from a drive, however, no sanity check
has been done for root nodes stored in inodes.

This patch fixes the issue by adding missing sanity check against b-tree
root nodes so that it's called when on-memory inodes are read from ifile,
inode metadata file.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agoscripts/gdb: add empty package initialization script
Jan Kiszka [Fri, 27 Feb 2015 23:51:53 +0000 (15:51 -0800)]
scripts/gdb: add empty package initialization script

This got lost during the initial merge process: Python requires an
__init__.py script, even if empty, in order to accept a directory as
package.  Add it, this time as a non-empty file.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agortc: ds1685: remove superfluous checks for out-of-range u8 values
Geert Uytterhoeven [Fri, 27 Feb 2015 23:51:51 +0000 (15:51 -0800)]
rtc: ds1685: remove superfluous checks for out-of-range u8 values

drivers/rtc/rtc-ds1685.c: In function `ds1685_rtc_read_alarm':
drivers/rtc/rtc-ds1685.c:402: warning: comparison is always true due to limited range of data type
drivers/rtc/rtc-ds1685.c:409: warning: comparison is always true due to limited range of data type
drivers/rtc/rtc-ds1685.c:416: warning: comparison is always true due to limited range of data type
drivers/rtc/rtc-ds1685.c: In function `ds1685_rtc_set_alarm':
drivers/rtc/rtc-ds1685.c:475: warning: comparison is always true due to limited range of data type
drivers/rtc/rtc-ds1685.c:478: warning: comparison is always true due to limited range of data type
drivers/rtc/rtc-ds1685.c:481: warning: comparison is always true due to limited range of data type

u8 cannot contain a value larger than 0xff, hence drop the checks.
Wrapping the checks in unlikely() indicated some sense of humor, though ;-)

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Joshua Kinard <kumba@gentoo.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agortc: ds1685: fix ds1685_rtc_alarm_irq_enable build error
Arnd Bergmann [Fri, 27 Feb 2015 23:51:48 +0000 (15:51 -0800)]
rtc: ds1685: fix ds1685_rtc_alarm_irq_enable build error

The newly added ds1685 driver causes a build error when enabled without
CONFIG_RTC_INTF_DEV:

  drivers/rtc/rtc-ds1685.c:919:22: error: 'ds1685_rtc_alarm_irq_enable' undeclared here (not in a function)
    .alarm_irq_enable = ds1685_rtc_alarm_irq_enable,

Apparently the driver was incorrectly changed to reflect the interface
change from 16380c153a69c ("RTC: Convert rtc drivers to use the
alarm_irq_enable method"), which removed the respective #ifdef from all
other rtc drivers.

This does the same change that was merged for the other drivers before and
removes the #ifdef, allowing the interrupts to be enabled through the
in-kernel rtc interface independent of the existence of /dev/rtc.

Fixes: aaaf5fbf56f ("rtc: add driver for DS1685 family of real time clocks")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Joshua Kinard <kumba@gentoo.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agomemcg: fix low limit calculation
Michal Hocko [Fri, 27 Feb 2015 23:51:46 +0000 (15:51 -0800)]
memcg: fix low limit calculation

A memcg is considered low limited even when the current usage is equal to
the low limit.  This leads to interesting side effects e.g.
groups/hierarchies with no memory accounted are considered protected and
so the reclaim will emit MEMCG_LOW event when encountering them.

Another and much bigger issue was reported by Joonsoo Kim.  He has hit a
NULL ptr dereference with the legacy cgroup API which even doesn't have
low limit exposed.  The limit is 0 by default but the initial check fails
for memcg with 0 consumption and parent_mem_cgroup() would return NULL if
use_hierarchy is 0 and so page_counter_read would try to dereference NULL.

I suppose that the current implementation is just an overlook because the
documentation in Documentation/cgroups/unified-hierarchy.txt says:

  "The memory.low boundary on the other hand is a top-down allocated
  reserve.  A cgroup enjoys reclaim protection when it and all its
  ancestors are below their low boundaries"

Fix the usage and the low limit comparision in mem_cgroup_low accordingly.

Fixes: 241994ed8649 (mm: memcontrol: default hierarchy interface for memory)
Reported-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agomm/nommu: fix memory leak
Joonsoo Kim [Fri, 27 Feb 2015 23:51:43 +0000 (15:51 -0800)]
mm/nommu: fix memory leak

Maxime reported the following memory leak regression due to commit
dbc8358c7237 ("mm/nommu: use alloc_pages_exact() rather than its own
implementation").

On v3.19, I am facing a memory leak.  Each time I run a command one page
is lost.  Here an example with busybox's free command:

  / # free
               total       used       free     shared    buffers     cached
  Mem:          7928       1972       5956          0          0        492
  -/+ buffers/cache:       1480       6448
  / # free
               total       used       free     shared    buffers     cached
  Mem:          7928       1976       5952          0          0        492
  -/+ buffers/cache:       1484       6444
  / # free
               total       used       free     shared    buffers     cached
  Mem:          7928       1980       5948          0          0        492
  -/+ buffers/cache:       1488       6440
  / # free
               total       used       free     shared    buffers     cached
  Mem:          7928       1984       5944          0          0        492
  -/+ buffers/cache:       1492       6436
  / # free
               total       used       free     shared    buffers     cached
  Mem:          7928       1988       5940          0          0        492
  -/+ buffers/cache:       1496       6432

At some point, the system fails to sastisfy 256KB allocations:

  free: page allocation failure: order:6, mode:0xd0
  CPU: 0 PID: 67 Comm: free Not tainted 3.19.0-05389-gacf2cf1-dirty #64
  Hardware name: STM32 (Device Tree Support)
    show_stack+0xb/0xc
    warn_alloc_failed+0x97/0xbc
    __alloc_pages_nodemask+0x295/0x35c
    __get_free_pages+0xb/0x24
    alloc_pages_exact+0x19/0x24
    do_mmap_pgoff+0x423/0x658
    vm_mmap_pgoff+0x3f/0x4e
    load_flat_file+0x20d/0x4f8
    load_flat_binary+0x3f/0x26c
    search_binary_handler+0x51/0xe4
    do_execveat_common+0x271/0x35c
    do_execve+0x19/0x1c
    ret_fast_syscall+0x1/0x4a
  Mem-info:
  Normal per-cpu:
  CPU    0: hi:    0, btch:   1 usd:   0
  active_anon:0 inactive_anon:0 isolated_anon:0
   active_file:0 inactive_file:0 isolated_file:0
   unevictable:123 dirty:0 writeback:0 unstable:0
   free:1515 slab_reclaimable:17 slab_unreclaimable:139
   mapped:0 shmem:0 pagetables:0 bounce:0
   free_cma:0
  Normal free:6060kB min:352kB low:440kB high:528kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:492kB isolated(anon):0ks
  lowmem_reserve[]: 0 0
  Normal: 23*4kB (U) 22*8kB (U) 24*16kB (U) 23*32kB (U) 23*64kB (U) 23*128kB (U) 1*256kB (U) 0*512kB 0*1024kB 0*2048kB 0*4096kB = 6060kB
  123 total pagecache pages
  2048 pages of RAM
  1538 free pages
  66 reserved pages
  109 slab pages
  -46 pages shared
  0 pages swap cached
  nommu: Allocation of length 221184 from process 67 (free) failed
  Normal per-cpu:
  CPU    0: hi:    0, btch:   1 usd:   0
  active_anon:0 inactive_anon:0 isolated_anon:0
   active_file:0 inactive_file:0 isolated_file:0
   unevictable:123 dirty:0 writeback:0 unstable:0
   free:1515 slab_reclaimable:17 slab_unreclaimable:139
   mapped:0 shmem:0 pagetables:0 bounce:0
   free_cma:0
  Normal free:6060kB min:352kB low:440kB high:528kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:492kB isolated(anon):0ks
  lowmem_reserve[]: 0 0
  Normal: 23*4kB (U) 22*8kB (U) 24*16kB (U) 23*32kB (U) 23*64kB (U) 23*128kB (U) 1*256kB (U) 0*512kB 0*1024kB 0*2048kB 0*4096kB = 6060kB
  123 total pagecache pages
  Unable to allocate RAM for process text/data, errno 12 SEGV

This problem happens because we allocate ordered page through
__get_free_pages() in do_mmap_private() in some cases and we try to free
individual pages rather than ordered page in free_page_series().  In
this case, freeing pages whose refcount is not 0 won't be freed to the
page allocator so memory leak happens.

To fix the problem, this patch changes __get_free_pages() to
alloc_pages_exact() since alloc_pages_exact() returns
physically-contiguous pages but each pages are refcounted.

Fixes: dbc8358c7237 ("mm/nommu: use alloc_pages_exact() rather than its own implementation").
Reported-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Tested-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: <stable@vger.kernel.org> [3.19]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agoocfs2: update web page + git tree in documentation
Mark Fasheh [Fri, 27 Feb 2015 23:51:40 +0000 (15:51 -0800)]
ocfs2: update web page + git tree in documentation

We (the Ocfs2 project) recently moved the location of our ocfs2-tools
git tree and project web page.  The pertinent discussion can be seen
here:

  https://oss.oracle.com/pipermail/ocfs2-devel/2015-February/010579.html

The following patch updates the Ocfs2 documentation in MAINTAINERS,
ocfs2.txt, and dlmfs.txt.  I added our new official web page, changed
the location of our tools git tree and removed the link to Joel's
ancient kernel git tree - Andrew has handled our patches for a while
now.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9 years agox86: Init per-cpu shadow copy of CR4 on 32-bit CPUs too
Steven Rostedt [Fri, 27 Feb 2015 19:50:19 +0000 (14:50 -0500)]
x86: Init per-cpu shadow copy of CR4 on 32-bit CPUs too

Commit:

   1e02ce4cccdc ("x86: Store a per-cpu shadow copy of CR4")

added a shadow CR4 such that reads and writes that do not
modify the CR4 execute much faster than always reading the
register itself.

The change modified cpu_init() in common.c, so that the
shadow CR4 gets initialized before anything uses it.

Unfortunately, there's two cpu_init()s in common.c. There's
one for 64-bit and one for 32-bit. The commit only added
the shadow init to the 64-bit path, but the 32-bit path
needs the init too.

Link: http://lkml.kernel.org/r/20150227125208.71c36402@gandalf.local.home
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150227145019.2bdd4354@gandalf.local.home
Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agoMerge branch 'linus' into x86/urgent, to merge dependent patch
Ingo Molnar [Sat, 28 Feb 2015 07:03:10 +0000 (08:03 +0100)]
Merge branch 'linus' into x86/urgent, to merge dependent patch

Signed-off-by: Ingo Molnar <mingo@kernel.org>
9 years agoMerge branch 'tmon-fixes' of .git into next
Zhang Rui [Sat, 28 Feb 2015 06:07:03 +0000 (14:07 +0800)]
Merge branch 'tmon-fixes' of .git into next

9 years agothermal: int340x_thermal: Ignore missing _ART, _TRT tables
Srinivas Pandruvada [Thu, 26 Feb 2015 02:31:50 +0000 (18:31 -0800)]
thermal: int340x_thermal: Ignore missing _ART, _TRT tables

It is possible that _ART/_TRT tables are missing or have errors.
Ignore those failures, as INT3400 thermal zone is still required
for _OSC or mode switch.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
9 years agothermal/intel_powerclamp: add id for Avoton SoC
Miguel Bernal Marin [Thu, 19 Feb 2015 18:40:58 +0000 (12:40 -0600)]
thermal/intel_powerclamp: add id for Avoton SoC

Enable Intel Powerclamp driver on Atom* Processor C2000 Product
Family for Microservers (Avoton). Avoton - SoCs for micro-servers
has package C-states which can be used for idle injection.

Reported-by: Jose Navarro <jose.navarro@intel.com>
Suggested-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Tested-by: Jose Carlos Venegas Munoz <jos.c.venegas.munoz@intel.com>
Signed-off-by: Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
9 years agotools/thermal: tmon: silence 'set but not used' warnings
Brian Norris [Wed, 18 Feb 2015 02:18:36 +0000 (18:18 -0800)]
tools/thermal: tmon: silence 'set but not used' warnings

gcc complains about the 'cols' variable being unused. This is
unavoidable, given the ncurses getmaxyx() macro-based API, which wants
to assign to a variable directly, even when we're not going to use it.

Warning:

    gcc -O1 -Wall -Wshadow -W -Wformat -Wimplicit-function-declaration -Wimplicit-int -fstack-protector -D VERSION=\"1.0\"   -c -o tui.o tui.c
    tui.c: In function ‘show_dialogue’:
    tui.c:288:12: warning: variable ‘cols’ set but not used [-Wunused-but-set-variable]
      int rows, cols;
                ^

So, add a hack to get rid of that warning.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
9 years agotools/thermal: tmon: use pkg-config to determine library dependencies
Brian Norris [Wed, 18 Feb 2015 02:18:35 +0000 (18:18 -0800)]
tools/thermal: tmon: use pkg-config to determine library dependencies

Some distros (e.g., Arch Linux) don't package the tinfo library
separately from ncurses, so don't unconditionally include it. Instead,
use pkg-config.

The $(STATIC) ugliness is to handle the reported build case from commit
6b533269fb25 ("tools/thermal: tmon: fix compilation errors when building
statically"), where a developer wants to be able to build with:

  make LDFLAGS=-static

which requires an additional pkg-config flag.

Finally, support a lowest common denominator fallback (-lpanel
-lncurses) for build systems that don't have pkg-config entries for
ncurses.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
9 years agotools/thermal: tmon: support cross-compiling
Brian Norris [Wed, 18 Feb 2015 02:18:34 +0000 (18:18 -0800)]
tools/thermal: tmon: support cross-compiling

We might want to prepare CFLAGS outside of this Makefile, so don't
overwrite its initial value.

Then, support $(CROSS_COMPILE), so we can use a cross-compile toolchain.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
9 years agotools/thermal: tmon: add .gitignore
Brian Norris [Wed, 18 Feb 2015 02:18:33 +0000 (18:18 -0800)]
tools/thermal: tmon: add .gitignore

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
9 years agotools/thermal: tmon: fixup tui windowing calculations
Brian Norris [Wed, 18 Feb 2015 02:18:32 +0000 (18:18 -0800)]
tools/thermal: tmon: fixup tui windowing calculations

The number of rows in the dialog vary according to the number of cooling
devices. However, some of the windowing computations were assuming a
fixed number of rows. This computation is OK when we have between 4 and
9 cooling devices (and they wrap to the next column), but with fewer
devices, we end up printing off the end of the window.

This unifies the row computation into a single function and uses that
throughout the TUI code. This also accounts for increasing the number of
rows when there are more than 9 total cooling devices.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
9 years agotools/thermal: tmon: tui: don't hard-code dialog window size assumptions
Brian Norris [Wed, 18 Feb 2015 02:18:31 +0000 (18:18 -0800)]
tools/thermal: tmon: tui: don't hard-code dialog window size assumptions

We can use the ncurses API to get the number of rows.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
9 years agotools/thermal: tmon: add min/max macros
Brian Norris [Wed, 18 Feb 2015 02:18:30 +0000 (18:18 -0800)]
tools/thermal: tmon: add min/max macros

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
9 years agotools/thermal: tmon: add --target-temp parameter
Brian Norris [Wed, 18 Feb 2015 02:18:29 +0000 (18:18 -0800)]
tools/thermal: tmon: add --target-temp parameter

If we launch in daemon mode (--daemon), we don't have the ncurses UI,
but we might want to set the target temperature still. For example,
someone might stick the following in their boot script:

  tmon --control intel_powerclamp --target-temp 90 --log --daemon

This would turn on CPU idle injection when we're around 90 degrees
celsius, and would log temperature and throttling info to
/var/tmp/tmon.log.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
9 years agoMerge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm...
Linus Torvalds [Sat, 28 Feb 2015 00:18:33 +0000 (16:18 -0800)]
Merge tag 'fixes-for-linus' of git://git./linux/kernel/git/arm/arm-soc

Pull ARM SoC fixes from Arnd Bergmann:
 "The arm-soc bug fixes this time around are mostly for the omap
  platform, coming from a pull request from Tony Lindgren and are almost
  entirely fixing dts files.

  The other two changes enable support for the shmobile platform in
  generic armv7 kernels and change some properties in the ARM64
  reference board dts files"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: multi_v7_defconfig: Enable shmobile platforms
  arm64: Add L2 cache topology to ARM Ltd boards/models
  ARM: dts: am335x-bone*: usb0 is hardwired for peripheral
  ARM: dts: dra7x-evm: beagle-x15: Fix USB Host
  ARM: omap2plus_defconfig: Fix SATA boot
  ARM: omap2plus_defconfig: Enable OMAP NAND BCH driver
  ARM: dts: dra7: Correct the dma controller's property names
  ARM: dts: omap5: Correct the dma controller's property names
  ARM: dts: omap4: Correct the dma controller's property names
  ARM: dts: omap3: Correct the dma controller's property names
  ARM: dts: omap2: Correct the dma controller's property names
  ARM: dts: am437x-idk: fix sleep pinctrl state
  ARM: omap2plus_defconfig: enable TPS62362 regulator
  ARM: dts: am437x-idk: fix TPS62362 i2c bus
  ARM: dts: n900: Fix offset for smc91x ethernet
  ARM: dts: n900: fix i2c bus numbering
  ARM: dts: Fix USB dts configuration for dm816x
  ARM: dts: OMAP5: Fix SATA PHY node
  ARM: dts: DRA7: Fix SATA PHY node

9 years agoMerge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Linus Torvalds [Sat, 28 Feb 2015 00:09:37 +0000 (16:09 -0800)]
Merge tag 'arm64-fixes' of git://git./linux/kernel/git/arm64/linux

Pull arm64 fixes from Catalin Marinas:
 "Various arm64 fixes:
   - ftrace branch generation fix
   - branch instruction encoding fix
   - include files, guards and unused prototypes clean-up
   - minor VDSO ABI fix (clock_getres)
   - PSCI functions moved to .S to avoid compilation error with gcc 5
   - pte_modify fix to not ignore the mapping type
   - crypto: AES interleaved increased to 4x (for performance reasons)
   - text patching fix for modules
   - swiotlb increased back to 64MB
   - copy_siginfo_to_user32() fix for big endian"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: cpuidle: add asm/proc-fns.h inclusion
  arm64: compat Fix siginfo_t -> compat_siginfo_t conversion on big endian
  arm64: Increase the swiotlb buffer size 64MB
  arm64: Fix text patching logic when using fixmap
  arm64: crypto: increase AES interleave to 4x
  arm64: enable PTE type bit in the mask for pte_modify
  arm64: mm: remove unused functions and variable protoypes
  arm64: psci: move psci firmware calls out of line
  arm64: vdso: minor ABI fix for clock_getres
  arm64: guard asm/assembler.h against multiple inclusions
  arm64: insn: fix compare-and-branch encodings
  arm64: ftrace: fix ftrace_modify_graph_caller for branch replace

9 years agoMerge tag 'renesas-sh-drivers-for-v4.0' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sat, 28 Feb 2015 00:08:45 +0000 (16:08 -0800)]
Merge tag 'renesas-sh-drivers-for-v4.0' of git://git./linux/kernel/git/horms/renesas

Pull SH driver fix from Simon Horman:
 "Disable PM runtime for multi-platform r8a7740 with genpd"

* tag 'renesas-sh-drivers-for-v4.0' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
  drivers: sh: Disable PM runtime for multi-platform r8a7740 with genpd

9 years agoarm64: cpuidle: add asm/proc-fns.h inclusion
Lorenzo Pieralisi [Fri, 27 Feb 2015 17:54:31 +0000 (17:54 +0000)]
arm64: cpuidle: add asm/proc-fns.h inclusion

ARM64 CPUidle driver requires the cpu_do_idle function so that it can
be used to enter the shallowest idle state, and it is declared in
asm/proc-fns.h.

The current ARM64 CPUidle driver does not include asm/proc-fns.h
explicitly and it has so far relied on implicit inclusion from other
header files.

Owing to some header dependencies reshuffling this currently triggers
build failures when CONFIG_ARM64_64K_PAGES=y:

drivers/cpuidle/cpuidle-arm64.c: In function "arm64_enter_idle_state"
drivers/cpuidle/cpuidle-arm64.c:42:3: error: implicit declaration of
function "cpu_do_idle" [-Werror=implicit-function-declaration]
   cpu_do_idle();
   ^

This patch adds the explicit inclusion of the asm/proc-fns.h header file
in the arm64 asm/cpuidle.h header file, so that the build breakage is fixed
and the required header inclusion is added to the appropriate arch back-end
CPUidle header, already included by the CPUidle arm64 driver, where
CPUidle arch related function declarations belong.

Reported-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
9 years agoarm64: compat Fix siginfo_t -> compat_siginfo_t conversion on big endian
Catalin Marinas [Mon, 23 Feb 2015 15:13:40 +0000 (15:13 +0000)]
arm64: compat Fix siginfo_t -> compat_siginfo_t conversion on big endian

The native (64-bit) sigval_t union contains sival_int (32-bit) and
sival_ptr (64-bit). When a compat application invokes a syscall that
takes a sigval_t value (as part of a larger structure, e.g.
compat_sys_mq_notify, compat_sys_timer_create), the compat_sigval_t
union is converted to the native sigval_t with sival_int overlapping
with either the least or the most significant half of sival_ptr,
depending on endianness. When the corresponding signal is delivered to a
compat application, on big endian the current (compat_uptr_t)sival_ptr
cast always returns 0 since sival_int corresponds to the top part of
sival_ptr. This patch fixes copy_siginfo_to_user32() so that sival_int
is copied to the compat_siginfo_t structure.

Cc: <stable@vger.kernel.org>
Reported-by: Bamvor Jian Zhang <bamvor.zhangjian@huawei.com>
Tested-by: Bamvor Jian Zhang <bamvor.zhangjian@huawei.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
9 years agoarm64: Increase the swiotlb buffer size 64MB
Catalin Marinas [Thu, 5 Feb 2015 18:01:53 +0000 (18:01 +0000)]
arm64: Increase the swiotlb buffer size 64MB

With commit 3690951fc6d4 (arm64: Use swiotlb late initialisation), the
swiotlb buffer size is limited to MAX_ORDER_NR_PAGES. However, there are
platforms with 32-bit only devices that require bounce buffering via
swiotlb. This patch changes the swiotlb initialisation to an early 64MB
memblock allocation. In order to get the swiotlb buffer correctly
allocated (via memblock_virt_alloc_low_nopanic), this patch also defines
ARCH_LOW_ADDRESS_LIMIT to the maximum physical address capable of 32-bit
DMA.

Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
9 years agoMerge branch 'drm-atmel-hlcdc-fixes' of git://github.com/bbrezillon/linux-at91 into...
Dave Airlie [Fri, 27 Feb 2015 00:31:40 +0000 (10:31 +1000)]
Merge branch 'drm-atmel-hlcdc-fixes' of git://github.com/bbrezillon/linux-at91 into drm-fixes

minor atmel hclcdc fixes.

* 'drm-atmel-hlcdc-fixes' of git://github.com/bbrezillon/linux-at91:
  drm: atmel-hlcdc: remove clock polarity from crtc driver
  drm: atmel-hlcdc: remove useless pm_runtime_put_sync in probe
  drm: atmel-hlcdc: reset layer A2Q and UPDATE bits when disabling it