From f9eeef5918bbe1f2545d36280330dced25d6cf97 Mon Sep 17 00:00:00 2001 From: Wei Yongjun Date: Wed, 17 Aug 2022 08:03:32 +0000 Subject: [PATCH] fault-injection: make stacktrace filter works as expected stacktrace filter is checked after others, such as fail-nth, interval and probability. This make it doesn't work well as expected. Fix to running stacktrace filter before other filters. It will speed up fault inject testing for driver modules. Link: https://lkml.kernel.org/r/20220817080332.1052710-5-weiyongjun1@huawei.com Signed-off-by: Wei Yongjun Cc: Akinobu Mita Cc: Dan Williams Cc: Isabella Basso Cc: Josh Poimboeuf Cc: Kees Cook Cc: Miguel Ojeda Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Peter Zijlstra Cc: Rasmus Villemoes Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- lib/fault-inject.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/lib/fault-inject.c b/lib/fault-inject.c index d7819cacf890..6cff320c4eb4 100644 --- a/lib/fault-inject.c +++ b/lib/fault-inject.c @@ -102,10 +102,16 @@ static inline bool fail_stacktrace(struct fault_attr *attr) bool should_fail_ex(struct fault_attr *attr, ssize_t size, int flags) { + bool stack_checked = false; + if (in_task()) { unsigned int fail_nth = READ_ONCE(current->fail_nth); if (fail_nth) { + if (!fail_stacktrace(attr)) + return false; + + stack_checked = true; fail_nth--; WRITE_ONCE(current->fail_nth, fail_nth); if (!fail_nth) @@ -125,6 +131,9 @@ bool should_fail_ex(struct fault_attr *attr, ssize_t size, int flags) if (atomic_read(&attr->times) == 0) return false; + if (!stack_checked && !fail_stacktrace(attr)) + return false; + if (atomic_read(&attr->space) > size) { atomic_sub(size, &attr->space); return false; @@ -139,9 +148,6 @@ bool should_fail_ex(struct fault_attr *attr, ssize_t size, int flags) if (attr->probability <= get_random_u32_below(100)) return false; - if (!fail_stacktrace(attr)) - return false; - fail: if (!(flags & FAULT_NOWARN)) fail_dump(attr);