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| author | Kees Cook <keescook@chromium.org> | 2020-06-03 13:09:38 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-06-09 10:29:01 +0200 |
| commit | 0638dcc7e75fbb766761e7b4694d0f0f141bbbd1 (patch) | |
| tree | 79b3b3a12f7b495bbe6d742c493130a89fc4545e /mm | |
| parent | 1eb88dccb827adcb7c94c39becd71ad4d2d533a8 (diff) | |
| download | linux-0638dcc7e75fbb766761e7b4694d0f0f141bbbd1.tar.gz linux-0638dcc7e75fbb766761e7b4694d0f0f141bbbd1.tar.bz2 linux-0638dcc7e75fbb766761e7b4694d0f0f141bbbd1.zip | |
treewide: Remove uninitialized_var() usage
commit 3f649ab728cda8038259d8f14492fe400fbab911 upstream.
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 <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/frontswap.c | 2 | ||||
| -rw-r--r-- | mm/ksm.c | 2 | ||||
| -rw-r--r-- | mm/memcontrol.c | 2 | ||||
| -rw-r--r-- | mm/mempolicy.c | 4 | ||||
| -rw-r--r-- | mm/percpu.c | 2 | ||||
| -rw-r--r-- | mm/slub.c | 4 | ||||
| -rw-r--r-- | mm/swap.c | 4 |
7 files changed, 10 insertions, 10 deletions
diff --git a/mm/frontswap.c b/mm/frontswap.c index 60bb20e8a951..fd3337702513 100644 --- a/mm/frontswap.c +++ b/mm/frontswap.c @@ -446,7 +446,7 @@ static int __frontswap_shrink(unsigned long target_pages, void frontswap_shrink(unsigned long target_pages) { unsigned long pages_to_unuse = 0; - int uninitialized_var(type), ret; + int type, ret; /* * we don't want to hold swap_lock while doing a very @@ -2388,7 +2388,7 @@ next_mm: static void ksm_do_scan(unsigned int scan_npages) { struct rmap_item *rmap_item; - struct page *uninitialized_var(page); + struct page *page; while (scan_npages-- && likely(!freezing(current))) { cond_resched(); diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 16beae167d8c..0140629b7cb2 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1044,7 +1044,7 @@ struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, struct mem_cgroup *prev, struct mem_cgroup_reclaim_cookie *reclaim) { - struct mem_cgroup_reclaim_iter *uninitialized_var(iter); + struct mem_cgroup_reclaim_iter *iter; struct cgroup_subsys_state *css = NULL; struct mem_cgroup *memcg = NULL; struct mem_cgroup *pos = NULL; diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 36c2a9619ba5..2bf4ab7b2713 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1160,7 +1160,7 @@ int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from, static struct page *new_page(struct page *page, unsigned long start) { struct vm_area_struct *vma; - unsigned long uninitialized_var(address); + unsigned long address; vma = find_vma(current->mm, start); while (vma) { @@ -1555,7 +1555,7 @@ static int kernel_get_mempolicy(int __user *policy, unsigned long flags) { int err; - int uninitialized_var(pval); + int pval; nodemask_t nodes; addr = untagged_addr(addr); diff --git a/mm/percpu.c b/mm/percpu.c index 806bc16f88eb..2e4b286c88c8 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -2536,7 +2536,7 @@ static struct pcpu_alloc_info * __init pcpu_build_alloc_info( const size_t static_size = __per_cpu_end - __per_cpu_start; int nr_groups = 1, nr_units = 0; size_t size_sum, min_unit_size, alloc_size; - int upa, max_upa, uninitialized_var(best_upa); /* units_per_alloc */ + int upa, max_upa, best_upa; /* units_per_alloc */ int last_allocs, group, unit; unsigned int cpu, tcpu; struct pcpu_alloc_info *ai; diff --git a/mm/slub.c b/mm/slub.c index 17e663cf38f6..e978f647e92a 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1198,7 +1198,7 @@ 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); @@ -2888,7 +2888,7 @@ 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); diff --git a/mm/swap.c b/mm/swap.c index 38c3fa4308e2..1c5021b57e2c 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -763,8 +763,8 @@ void release_pages(struct page **pages, int nr) LIST_HEAD(pages_to_free); struct pglist_data *locked_pgdat = NULL; struct lruvec *lruvec; - unsigned long uninitialized_var(flags); - unsigned int uninitialized_var(lock_batch); + unsigned long flags; + unsigned int lock_batch; for (i = 0; i < nr; i++) { struct page *page = pages[i]; |