powerpc: Fix smp_processor_id() in preemptible splat in set_breakpoint
Currently, on 8641D, which doesn't set CONFIG_HAVE_HW_BREAKPOINT
we get the following splat:
BUG: using smp_processor_id() in preemptible [
00000000] code: login/1382
caller is set_breakpoint+0x1c/0xa0
CPU: 0 PID: 1382 Comm: login Not tainted
3.15.0-rc3-00041-g2aafe1a4d451 #1
Call Trace:
[
decd5d80] [
c0008dc4] show_stack+0x50/0x158 (unreliable)
[
decd5dc0] [
c03c6fa0] dump_stack+0x7c/0xdc
[
decd5de0] [
c01f8818] check_preemption_disabled+0xf4/0x104
[
decd5e00] [
c00086b8] set_breakpoint+0x1c/0xa0
[
decd5e10] [
c00d4530] flush_old_exec+0x2bc/0x588
[
decd5e40] [
c011c468] load_elf_binary+0x2ac/0x1164
[
decd5ec0] [
c00d35f8] search_binary_handler+0xc4/0x1f8
[
decd5ef0] [
c00d4ee8] do_execve+0x3d8/0x4b8
[
decd5f40] [
c001185c] ret_from_syscall+0x0/0x38
--- Exception: c01 at 0xfeee554
LR = 0xfeee7d4
The call path in this case is:
flush_thread
--> set_debug_reg_defaults
--> set_breakpoint
--> __get_cpu_var
Since preemption is enabled in the cleanup of flush thread, and
there is no need to disable it, introduce the distinction between
set_breakpoint and __set_breakpoint, leaving only the flush_thread
instance as the current user of set_breakpoint.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
projects / GitHub / LineageOS / android_kernel_motorola_exynos9610.git / commit