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authorGravatar Rohan McLure <rmclure@linux.ibm.com> 2023-02-06 13:17:58 +1100
committerGravatar Michael Ellerman <mpe@ellerman.id.au> 2023-02-10 22:19:56 +1100
commit2a7ce82dc46c591c9244057d89a6591c9639b9b9 (patch)
treeb974bee0b27aae9971095592dcbd58572c2728e9 /arch/powerpc/kernel
parentpowerpc/kcsan: Add exclusions from instrumentation (diff)
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powerpc/kcsan: Exclude udelay to prevent recursive instrumentation
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
Diffstat (limited to 'arch/powerpc/kernel')
-rw-r--r--arch/powerpc/kernel/time.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index d68de3618741..b894029f53db 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -356,7 +356,7 @@ void vtime_flush(struct task_struct *tsk)
}
#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
-void __delay(unsigned long loops)
+void __no_kcsan __delay(unsigned long loops)
{
unsigned long start;
@@ -377,7 +377,7 @@ 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);
}