From: majianpeng Date: Fri, 18 May 2012 00:03:26 +0000 (-0700) Subject: slub: missing test for partial pages flush work in flush_all() X-Git-Tag: upstream/snapshot3+hdmi~7499^2~1 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=02e1a9cd1ea99b67a668f13b61fdf5d42115db0a;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git slub: missing test for partial pages flush work in flush_all() I found some kernel messages such as: SLUB raid5-md127: kmem_cache_destroy called for cache that still has objects. Pid: 6143, comm: mdadm Tainted: G O 3.4.0-rc6+ #75 Call Trace: kmem_cache_destroy+0x328/0x400 free_conf+0x2d/0xf0 [raid456] stop+0x41/0x60 [raid456] md_stop+0x1a/0x60 [md_mod] do_md_stop+0x74/0x470 [md_mod] md_ioctl+0xff/0x11f0 [md_mod] blkdev_ioctl+0xd8/0x7a0 block_ioctl+0x3b/0x40 do_vfs_ioctl+0x96/0x560 sys_ioctl+0x91/0xa0 system_call_fastpath+0x16/0x1b Then using kmemleak I found these messages: unreferenced object 0xffff8800b6db7380 (size 112): comm "mdadm", pid 5783, jiffies 4294810749 (age 90.589s) hex dump (first 32 bytes): 01 01 db b6 ad 4e ad de ff ff ff ff ff ff ff ff .....N.......... ff ff ff ff ff ff ff ff 98 40 4a 82 ff ff ff ff .........@J..... backtrace: kmemleak_alloc+0x21/0x50 kmem_cache_alloc+0xeb/0x1b0 kmem_cache_open+0x2f1/0x430 kmem_cache_create+0x158/0x320 setup_conf+0x649/0x770 [raid456] run+0x68b/0x840 [raid456] md_run+0x529/0x940 [md_mod] do_md_run+0x18/0xc0 [md_mod] md_ioctl+0xba8/0x11f0 [md_mod] blkdev_ioctl+0xd8/0x7a0 block_ioctl+0x3b/0x40 do_vfs_ioctl+0x96/0x560 sys_ioctl+0x91/0xa0 system_call_fastpath+0x16/0x1b This bug was introduced by commit a8364d5555b ("slub: only IPI CPUs that have per cpu obj to flush"), which did not include checks for per cpu partial pages being present on a cpu. Signed-off-by: majianpeng Cc: Gilad Ben-Yossef Acked-by: Christoph Lameter Cc: Pekka Enberg Tested-by: Jeff Layton Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/slub.c b/mm/slub.c index ffe13fd..80848cd 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -2040,7 +2040,7 @@ static bool has_cpu_slab(int cpu, void *info) struct kmem_cache *s = info; struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); - return !!(c->page); + return c->page || c->partial; } static void flush_all(struct kmem_cache *s)