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| author | Rohan McLure <rmclure@linux.ibm.com> | 2023-02-06 13:17:58 +1100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-03-17 08:45:14 +0100 |
| commit | 9a61a3a6ec660915b641dacc6ac40bb52cc9e06b (patch) | |
| tree | d344ca7d22283ae409f2a71f6d8caf926a11c963 | |
| parent | 5ddcb0a348194b372e9f0d027ba7eedb6b5bd1e0 (diff) | |
| download | linux-9a61a3a6ec660915b641dacc6ac40bb52cc9e06b.tar.gz linux-9a61a3a6ec660915b641dacc6ac40bb52cc9e06b.tar.bz2 linux-9a61a3a6ec660915b641dacc6ac40bb52cc9e06b.zip | |
powerpc/kcsan: Exclude udelay to prevent recursive instrumentation
[ Upstream commit 2a7ce82dc46c591c9244057d89a6591c9639b9b9 ]
In order for KCSAN to increase its likelihood of observing a data race,
it sets a watchpoint on memory accesses and stalls, allowing for
detection of conflicting accesses by other kernel threads or interrupts.
Stalls are implemented by injecting a call to udelay in instrumented code.
To prevent recursive instrumentation, exclude udelay from being instrumented.
Signed-off-by: Rohan McLure <rmclure@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230206021801.105268-3-rmclure@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | arch/powerpc/kernel/time.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index 1d20f0f77a92..ba9b54d35f57 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -436,7 +436,7 @@ void vtime_flush(struct task_struct *tsk) #define calc_cputime_factors() #endif -void __delay(unsigned long loops) +void __no_kcsan __delay(unsigned long loops) { unsigned long start; @@ -457,7 +457,7 @@ void __delay(unsigned long loops) } EXPORT_SYMBOL(__delay); -void udelay(unsigned long usecs) +void __no_kcsan udelay(unsigned long usecs) { __delay(tb_ticks_per_usec * usecs); } |