ide-disk: Fix request requeuing
authorBorislav Petkov <bp@alien8.de>
Mon, 3 Oct 2011 18:28:18 +0000 (14:28 -0400)
committerGreg Kroah-Hartman <gregkh@suse.de>
Sun, 16 Oct 2011 21:14:51 +0000 (14:14 -0700)
commit3217df8e225c8579293fd2e193ba5cee709b6eba
treefc527832020b5648dead7aada6cdd16e35229775
parent4e41ce698822a9a2cfd324a11ea44f60fc95c871
ide-disk: Fix request requeuing

commit 2c8fc867602e385fd2abe76da0b6bda8ed907547 upstream.

Simon Kirby reported that on his RAID setup with idedisk underneath
the box OOMs after a couple of days of runtime. Running with
CONFIG_DEBUG_KMEMLEAK pointed to idedisk_prep_fn() which unconditionally
allocates an ide_cmd struct. However, ide_requeue_and_plug() can be
called more than once per request, either from the request issue or the
IRQ handler path and do blk_peek_request() ends up in idedisk_prep_fn()
repeatedly, allocating a struct ide_cmd everytime and "forgetting" the
previous pointer.

Make sure the code reuses the old allocated chunk.

Reported-and-tested-by: Simon Kirby <sim@hostway.ca>
Link: http://marc.info/?l=linux-kernel&m=131667641517919
Link: http://lkml.kernel.org/r/20110922072643.GA27232@hostway.ca
Signed-off-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/ide/ide-disk.c