linux

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Ammar Faizi 55bd0545d2 x86/delay: Fix the wrong asm constraint in delay_loop()

[ Upstream commit b86eb74098a92afd789da02699b4b0dd3f73b889 ]

The asm constraint does not reflect the fact that the asm statement can
modify the value of the local variable loops. Which it does.

Specifying the wrong constraint may lead to undefined behavior, it may
clobber random stuff (e.g. local variable, important temporary value in
regs, etc.). This is especially dangerous when the compiler decides to
inline the function and since it doesn't know that the value gets
modified, it might decide to use it from a register directly without
reloading it.

Change the constraint to "+a" to denote that the first argument is an
input and an output argument.

  [ bp: Fix typo, massage commit message. ]

Fixes: e01b70ef3eb3 ("x86: fix bug in arch/i386/lib/delay.c file, delay_loop function")
Signed-off-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220329104705.65256-2-ammarfaizi2@gnuweeb.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

2022-06-14 16:52:31 +02:00

alpha

alpha: Declare virt_to_phys and virt_to_bus parameter as pointer to volatile

2021-10-06 10:23:40 +02:00

arc

ARC: entry: fix syscall_trace_exit argument

2022-04-27 13:14:11 +02:00

arm

ARM: hisi: Add missing of_node_put after of_find_compatible_node

2022-06-14 16:52:30 +02:00

arm64

arm64: module: remove (NOLOAD) from linker script