Commit 956e46ef authored May 08, 2013 by Chris Mason Committed by Linus Torvalds May 08, 2013

mm/slab: Fix crash during slab init



Commit 8a965b3b ("mm, slab_common: Fix bootstrap creation of kmalloc
caches") introduced a regression that caused us to crash early during
boot.  The commit was introducing ordering of slab creation, making sure
two odd-sized slabs were created after specific powers of two sizes.

But, if any of the power of two slabs were created earlier during boot,
slabs at index 1 or 2 might not get created at all.  This patch makes
sure none of the slabs get skipped.

Tony Lindgren bisected this down to the offending commit, which really
helped because bisect kept bringing me to almost but not quite this one.

Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent ebb37277

mm/slab_common.c

+10 −10

Original line number	Diff line number	Diff line
		@@ -446,6 +446,7 @@ void __init create_kmalloc_caches(unsigned long flags)
		if (!kmalloc_caches[i]) {
		kmalloc_caches[i] = create_kmalloc_cache(NULL,
		1 << i, flags);
		}

		/*
		* Caches that are not of the two-to-the-power-of size.
		@@ -458,7 +459,6 @@ void __init create_kmalloc_caches(unsigned long flags)
		if (KMALLOC_MIN_SIZE <= 64 && !kmalloc_caches[2] && i == 7)
		kmalloc_caches[2] = create_kmalloc_cache(NULL, 192, flags);
		}
		}

		/* Kmalloc array is now usable */
		slab_state = UP;

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