It's a bit weird that WRITE_ONCE() evaluates to the value it stores and it's also different to smp_store_release(), which can't be used this way.
In preparation for preventing this in WRITE_ONCE(), change the fault injection code to use a local variable instead. Cc: Akinobu Mita <[email protected]> Signed-off-by: Will Deacon <[email protected]> --- lib/fault-inject.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/lib/fault-inject.c b/lib/fault-inject.c index 8186ca84910b..ce12621b4275 100644 --- a/lib/fault-inject.c +++ b/lib/fault-inject.c @@ -106,7 +106,9 @@ bool should_fail(struct fault_attr *attr, ssize_t size) unsigned int fail_nth = READ_ONCE(current->fail_nth); if (fail_nth) { - if (!WRITE_ONCE(current->fail_nth, fail_nth - 1)) + fail_nth--; + WRITE_ONCE(current->fail_nth, fail_nth); + if (!fail_nth) goto fail; return false; -- 2.26.2.645.ge9eca65c58-goog
