Clang warns: kernel/resource.c:1281:53: warning: operator '?:' has lower precedence than '|'; '|' will be evaluated first [-Wbitwise-conditional-parentheses] new_res = alloc_resource(GFP_KERNEL | alloc_nofail ? __GFP_NOFAIL : 0); ~~~~~~~~~~~~~~~~~~~~~~~~~ ^ kernel/resource.c:1281:53: note: place parentheses around the '|' expression to silence this warning new_res = alloc_resource(GFP_KERNEL | alloc_nofail ? __GFP_NOFAIL : 0); ~~~~~~~~~~~~~~~~~~~~~~~~~ ^ kernel/resource.c:1281:53: note: place parentheses around the '?:' expression to evaluate it first new_res = alloc_resource(GFP_KERNEL | alloc_nofail ? __GFP_NOFAIL : 0); ^ ( ) 1 warning generated.
Add the parentheses as it was clearly intended for the ternary condition to be evaluated first. Fixes: 5fd23bd0d739 ("kernel/resource: make release_mem_region_adjustable() never fail") Link: https://github.com/ClangBuiltLinux/linux/issues/1159 Signed-off-by: Nathan Chancellor <natechancel...@gmail.com> --- Presumably, this will be squashed but I included a fixes tag nonetheless. Apologies if this has already been noticed and fixed already, I did not find anything on LKML. kernel/resource.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/resource.c b/kernel/resource.c index ca2a666e4317..3ae2f56cc79d 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -1278,7 +1278,7 @@ void release_mem_region_adjustable(resource_size_t start, resource_size_t size) * similarly). */ retry: - new_res = alloc_resource(GFP_KERNEL | alloc_nofail ? __GFP_NOFAIL : 0); + new_res = alloc_resource(GFP_KERNEL | (alloc_nofail ? __GFP_NOFAIL : 0)); p = &parent->child; write_lock(&resource_lock); base-commit: 40ee82f47bf297e31d0c47547cd8f24ede52415a -- 2.28.0