slub: fix high order page allocation problem with __GFP_NOFAIL (80c3a998) · Commits · 戴 / test

SLUB already try to allocate high order page with clearing __GFP_NOFAIL. But, when allocating shadow page for kmemcheck, it missed clearing the flag. This trigger WARN_ON_ONCE() reported by Christian Casteyde. https://bugzilla.kernel.org/show_bug.cgi?id=65991 https://lkml.org/lkml/2013/12/3/764 This patch fix this situation by using same allocation flag as original allocation. Reported-by:

Christian Casteyde <casteyde.christian@free.fr> Acked-by:

David Rientjes <rientjes@google.com> Signed-off-by:

Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by:

Pekka Enberg <penberg@kernel.org>

mm/slub.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -1350,11 +1350,12 @@ static struct page allocate_slab(struct kmem_cache s, gfp_t flags, int node)
		page = alloc_slab_page(alloc_gfp, node, oo);
		if (unlikely(!page)) {
		oo = s->min;
		alloc_gfp = flags;
		/*
		* Allocation may have failed due to fragmentation.
		* Try a lower order alloc if possible
		*/
		page = alloc_slab_page(flags, node, oo);
		page = alloc_slab_page(alloc_gfp, node, oo);

		if (page)
		stat(s, ORDER_FALLBACK);
		@@ -1364,7 +1365,7 @@ static struct page allocate_slab(struct kmem_cache s, gfp_t flags, int node)
		&& !(s->flags & (SLAB_NOTRACK \| DEBUG_DEFAULT_FLAGS))) {
		int pages = 1 << oo_order(oo);

		kmemcheck_alloc_shadow(page, oo_order(oo), flags, node);
		kmemcheck_alloc_shadow(page, oo_order(oo), alloc_gfp, node);

		/*
		* Objects from caches that have a constructor don't get

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