Wu Fengguang a5e2201319 writeback: fix dereferencing NULL bdi->dev on trace_writeback_queue ... commit 977b7e3a52 upstream. When a SD card is hot removed without umount, del_gendisk() will call bdi_unregister() without destroying/freeing it. This leaves the bdi in the bdi->dev = NULL, bdi->wb.task = NULL, bdi->bdi_list removed state. When sync(2) gets the bdi before bdi_unregister() and calls bdi_queue_work() after the unregister, trace_writeback_queue will be dereferencing the NULL bdi->dev. Fix it with a simple test for NULL. LKML-reference: http://lkml.org/lkml/2012/1/18/346 Reported-by: Rabin Vincent <rabin@rab.in> Tested-by: Namjae Jeon <linkinjeon@gmail.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2012-02-20 12:48:11 -08:00
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acpi	ACPI: Store SRAT table revision	2012-01-25 17:24:57 -08:00
asm-generic	Merge branches 'gpio/merge' and 'spi/merge' of git://git.secretlab.ca/git/linux-2.6	2011-06-17 10:36:32 -07:00
crypto
drm	drm: Fix authentication kernel crash	2012-02-03 09:18:52 -08:00
keys	libceph: Create a new key type "ceph".	2011-03-29 12:11:24 -07:00
linux	lib: proportion: lower PROP_MAX_SHIFT to 32 on 64-bit kernel	2012-02-20 12:48:10 -08:00
math-emu
media	[media] tuner-core/v4l2-subdev: document that the type field has to be filled in	2011-07-07 15:04:23 -03:00
mtd	UBI: fix minor stylistic issues	2011-04-14 11:34:41 +03:00
net	net: fix NULL dereferences in check_peer_redir()	2012-02-13 11:06:13 -08:00
pcmcia	pcmcia: Make declaration and uses of struct pcmcia_device_id const	2011-05-06 07:46:15 +02:00
rdma	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband	2011-05-26 12:13:57 -07:00
rxrpc	Fix common misspellings	2011-03-31 11:26:23 -03:00
scsi	[SCSI] libsas: Add option for SATA soft reset	2011-05-26 22:49:33 -05:00
sound	ALSA: sb16 - Fix build errors on MIPS and others with 13bit ioctl size	2011-06-30 15:33:57 +02:00
target	target: Set additional sense length field in sense data	2012-01-25 17:25:00 -08:00
trace	writeback: fix dereferencing NULL bdi->dev on trace_writeback_queue	2012-02-20 12:48:11 -08:00
video	Merge branches 'common/fbdev' and 'common/fbdev-meram' of master.kernel.org:/pub/scm/linux/kernel/git/lethal/sh-2.6	2011-05-24 15:49:57 +09:00
xen	xen/xenbus: Reject replies with payload > XENSTORE_PAYLOAD_MAX.	2012-01-25 17:24:41 -08:00
Kbuild