kevin/linux
1
Fork 0
Code

locking/ww-mutex: Fix uninitialized use of ret in test_aa()

Browse Source 
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: 12235da8c8 ("kernel/locking: Add context to ww_mutex_trylock()")
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://lore.kernel.org/r/20210922145822.3935141-1-nathan@kernel.org
This commit is contained in:
Nathan Chancellor 2021-09-22 07:58:22 -07:00 committed by Peter Zijlstra
parent f7427ba5ce
commit 1415b49bcd
1 changed files with 2 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
kernel/locking/test-ww_mutex.c
View File

@ -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;
}