From: Christian Brauner Date: Wed, 25 Mar 2026 16:34:00 +0000 (+0100) Subject: fat: fix stack frame size warnings in KUnit tests X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=94505767bd32f8a240cf3590776b16a12d75d98e;p=thirdparty%2Fkernel%2Flinux.git fat: fix stack frame size warnings in KUnit tests The kernel test robot reported that on hexagon with clang, several test functions in fat_test.c exceed the 1280-byte stack frame limit. The root cause is the compound literal assignment in fat_test_set_time_offset(): *sbi = (struct msdos_sb_info){}; struct msdos_sb_info contains two hash tables of 256 hlist_head entries (FAT_HASH_SIZE), making it several kilobytes. The compound literal creates a temporary on the stack, and when clang inlines fat_test_set_time_offset() into each test function, the large temporary inflates every caller's stack frame beyond the limit. Replace the compound literal with memset() which zeroes the struct in-place without a stack temporary. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202603251755.4UYY1Rcd-lkp@intel.com/ Signed-off-by: Christian Brauner --- diff --git a/fs/fat/fat_test.c b/fs/fat/fat_test.c index 5c97a7fcc41d0..886bf044a9f1d 100644 --- a/fs/fat/fat_test.c +++ b/fs/fat/fat_test.c @@ -218,7 +218,7 @@ KUNIT_ARRAY_PARAM(fat_truncate_atime, truncate_atime_test_cases, static void fat_test_set_time_offset(struct msdos_sb_info *sbi, int time_offset) { - *sbi = (struct msdos_sb_info){}; + memset(sbi, 0, sizeof(*sbi)); sbi->options.tz_set = 1; sbi->options.time_offset = time_offset; }