The following commit has been merged into the locking/core branch of tip: Commit-ID: 1415b49bcd321bca7347f43f8b269c91ec46d1dc Gitweb: https://git.kernel.org/tip/1415b49bcd321bca7347f43f8b269c91ec46d1dc Author: Nathan Chancellor <nathan@xxxxxxxxxx> AuthorDate: Wed, 22 Sep 2021 07:58:22 -07:00 Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx> CommitterDate: Fri, 01 Oct 2021 13:57:49 +02:00 locking/ww-mutex: Fix uninitialized use of ret in test_aa() Clang warns: kernel/locking/test-ww_mutex.c:138:7: error: variable 'ret' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized] if (!ww_mutex_trylock(&mutex, &ctx)) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/test-ww_mutex.c:172:9: note: uninitialized use occurs here return ret; ^~~ kernel/locking/test-ww_mutex.c:138:3: note: remove the 'if' if its condition is always false if (!ww_mutex_trylock(&mutex, &ctx)) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/test-ww_mutex.c:125:9: note: initialize the variable 'ret' to silence this warning int ret; ^ = 0 1 error generated. Assign !ww_mutex_trylock(...) to ret so that it is always initialized. Fixes: 12235da8c80a ("kernel/locking: Add context to ww_mutex_trylock()") Reported-by: "kernelci.org bot" <bot@xxxxxxxxxxxx> Reported-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Acked-by: Waiman Long <longman@xxxxxxxxxx> Link: https://lore.kernel.org/r/20210922145822.3935141-1-nathan@xxxxxxxxxx --- kernel/locking/test-ww_mutex.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/locking/test-ww_mutex.c b/kernel/locking/test-ww_mutex.c index d63ac41..3530041 100644 --- a/kernel/locking/test-ww_mutex.c +++ b/kernel/locking/test-ww_mutex.c @@ -135,7 +135,8 @@ static int test_aa(bool trylock) goto out; } } else { - if (!ww_mutex_trylock(&mutex, &ctx)) { + ret = !ww_mutex_trylock(&mutex, &ctx); + if (ret) { pr_err("%s: initial trylock failed!\n", __func__); goto out; }
![]() |