From 3f649ab728cda8038259d8f14492fe400fbab911 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 3 Jun 2020 13:09:38 -0700 Subject: treewide: Remove uninitialized_var() usage Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. In preparation for removing[2] the[3] macro[4], remove all remaining needless uses with the following script: git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \ xargs perl -pi -e \ 's/\buninitialized_var\(([^\)]+)\)/\1/g; s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;' drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid pathological white-space. No outstanding warnings were found building allmodconfig with GCC 9.3.0 for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64, alpha, and m68k. [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Reviewed-by: Leon Romanovsky # drivers/infiniband and mlx4/mlx5 Acked-by: Jason Gunthorpe # IB Acked-by: Kalle Valo # wireless drivers Reviewed-by: Chao Yu # erofs Signed-off-by: Kees Cook --- mm/slub.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'mm/slub.c') diff --git a/mm/slub.c b/mm/slub.c index ef303070d175..f226d66408ee 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1218,7 +1218,7 @@ static noinline int free_debug_processing( struct kmem_cache_node *n = get_node(s, page_to_nid(page)); void *object = head; int cnt = 0; - unsigned long uninitialized_var(flags); + unsigned long flags; int ret = 0; spin_lock_irqsave(&n->list_lock, flags); @@ -2901,7 +2901,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page, struct page new; unsigned long counters; struct kmem_cache_node *n = NULL; - unsigned long uninitialized_var(flags); + unsigned long flags; stat(s, FREE_SLOWPATH); -- cgit v1.2.3