From: Qi Zheng zhengqi.arch@bytedance.com
mainline inclusion from mainline-v5.19-rc1 commit 3f913fc5f9745613088d3c569778c9813ab9c129 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I610B5 CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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We expect no warnings to be issued when we specify __GFP_NOWARN, but currently in paths like alloc_pages() and kmalloc(), there are still some warnings printed, fix it.
But for some warnings that report usage problems, we don't deal with them. If such warnings are printed, then we should fix the usage problems. Such as the following case:
WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1));
[zhengqi.arch@bytedance.com: v2] Link: https://lkml.kernel.org/r/20220511061951.1114-1-zhengqi.arch@bytedance.com Link: https://lkml.kernel.org/r/20220510113809.80626-1-zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng zhengqi.arch@bytedance.com Cc: Akinobu Mita akinobu.mita@gmail.com Cc: Vlastimil Babka vbabka@suse.cz Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: Jiri Slaby jirislaby@kernel.org Cc: Steven Rostedt (Google) rostedt@goodmis.org Signed-off-by: Andrew Morton akpm@linux-foundation.org
Conflict: mm/internal.h mm/page_alloc.c
Signed-off-by: Ye Weihua yeweihua4@huawei.com Reviewed-by: Kuohai Xu xukuohai@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- include/linux/fault-inject.h | 2 ++ lib/fault-inject.c | 3 +++ mm/failslab.c | 3 +++ mm/internal.h | 15 +++++++++++++++ mm/page_alloc.c | 16 +++++++++------- 5 files changed, 32 insertions(+), 7 deletions(-)
diff --git a/include/linux/fault-inject.h b/include/linux/fault-inject.h index e525f6957c49..d506ee960ffd 100644 --- a/include/linux/fault-inject.h +++ b/include/linux/fault-inject.h @@ -20,6 +20,7 @@ struct fault_attr { atomic_t space; unsigned long verbose; bool task_filter; + bool no_warn; unsigned long stacktrace_depth; unsigned long require_start; unsigned long require_end; @@ -39,6 +40,7 @@ struct fault_attr { .ratelimit_state = RATELIMIT_STATE_INIT_DISABLED, \ .verbose = 2, \ .dname = NULL, \ + .no_warn = false, \ }
#define DECLARE_FAULT_ATTR(name) struct fault_attr name = FAULT_ATTR_INITIALIZER diff --git a/lib/fault-inject.c b/lib/fault-inject.c index ce12621b4275..423784d9c058 100644 --- a/lib/fault-inject.c +++ b/lib/fault-inject.c @@ -41,6 +41,9 @@ EXPORT_SYMBOL_GPL(setup_fault_attr);
static void fail_dump(struct fault_attr *attr) { + if (attr->no_warn) + return; + if (attr->verbose > 0 && __ratelimit(&attr->ratelimit_state)) { printk(KERN_NOTICE "FAULT_INJECTION: forcing a failure.\n" "name %pd, interval %lu, probability %lu, " diff --git a/mm/failslab.c b/mm/failslab.c index f92fed91ac23..58df9789f1d2 100644 --- a/mm/failslab.c +++ b/mm/failslab.c @@ -30,6 +30,9 @@ bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags) if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB)) return false;
+ if (gfpflags & __GFP_NOWARN) + failslab.attr.no_warn = true; + return should_fail(&failslab.attr, s->object_size); }
diff --git a/mm/internal.h b/mm/internal.h index 8ef8cdd929fa..13f78c5cd961 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -32,6 +32,21 @@ /* Do not use these with a slab allocator */ #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
+/* + * Different from WARN_ON_ONCE(), no warning will be issued + * when we specify __GFP_NOWARN. + */ +#define WARN_ON_ONCE_GFP(cond, gfp) ({ \ + static bool __section(".data.once") __warned; \ + int __ret_warn_once = !!(cond); \ + \ + if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \ + __warned = true; \ + WARN_ON(1); \ + } \ + unlikely(__ret_warn_once); \ +}) + void page_writeback_init(void);
vm_fault_t do_swap_page(struct vm_fault *vmf); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 2feb99a0b98f..81840e28d78f 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3555,6 +3555,9 @@ static bool __should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) (gfp_mask & __GFP_DIRECT_RECLAIM)) return false;
+ if (gfp_mask & __GFP_NOWARN) + fail_page_alloc.attr.no_warn = true; + return should_fail(&fail_page_alloc.attr, 1 << order); }
@@ -4130,7 +4133,8 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, */
/* Exhausted what can be done so it's blame time */ - if (out_of_memory(&oc) || WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL)) { + if (out_of_memory(&oc) || + WARN_ON_ONCE_GFP(gfp_mask & __GFP_NOFAIL, gfp_mask)) { *did_some_progress = 1;
/* @@ -4914,7 +4918,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, * All existing users of the __GFP_NOFAIL are blockable, so warn * of any new users that actually require GFP_NOWAIT */ - if (WARN_ON_ONCE(!can_direct_reclaim)) + if (WARN_ON_ONCE_GFP(!can_direct_reclaim, gfp_mask)) goto fail;
/* @@ -4922,7 +4926,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, * because we cannot reclaim anything and only can loop waiting * for somebody to do a work for us */ - WARN_ON_ONCE(current->flags & PF_MEMALLOC); + WARN_ON_ONCE_GFP(current->flags & PF_MEMALLOC, gfp_mask);
/* * non failing costly orders are a hard requirement which we @@ -4930,7 +4934,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, * so that we can identify them and convert them to something * else. */ - WARN_ON_ONCE(order > PAGE_ALLOC_COSTLY_ORDER); + WARN_ON_ONCE_GFP(order > PAGE_ALLOC_COSTLY_ORDER, gfp_mask);
/* * Help non-failing allocations by giving them access to memory @@ -5295,10 +5299,8 @@ struct page *__alloc_pages(gfp_t gfp, unsigned int order, int preferred_nid, * There are several places where we assume that the order value is sane * so bail out early if the request is out of bound. */ - if (unlikely(order >= MAX_ORDER)) { - WARN_ON_ONCE(!(gfp & __GFP_NOWARN)); + if (WARN_ON_ONCE_GFP(order >= MAX_ORDER, gfp)) return NULL; - }
gfp &= gfp_allowed_mask;