Commit f9eeef59 authored by Wei Yongjun's avatar Wei Yongjun Committed by Andrew Morton
Browse files

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: default avatarWei Yongjun <weiyongjun1@huawei.com>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Isabella Basso <isabbasso@riseup.net>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 01999074

lib/fault-inject.c

+9 −3
Original line number Diff line number Diff line
@@ -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);