majianpeng d206dcfa98 md/raid5: Before freeing old multi-thread worker, it should flush them. ... When changing group_thread_cnt from sysfs entry, the kernel can oops. The kernel messages are: [ 740.961389] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 [ 740.961444] IP: [<ffffffff81062570>] process_one_work+0x30/0x500 [ 740.961476] PGD b9013067 PUD b651e067 PMD 0 [ 740.961503] Oops: 0000 [#1] SMP [ 740.961525] Modules linked in: netconsole e1000e ptp pps_core [ 740.961577] CPU: 0 PID: 3683 Comm: kworker/u8:5 Not tainted 3.12.0+ #23 [ 740.961602] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS 080015 11/09/2011 [ 740.961646] task: ffff88013abe0000 ti: ffff88013a246000 task.ti: ffff88013a246000 [ 740.961673] RIP: 0010:[<ffffffff81062570>] [<ffffffff81062570>] process_one_work+0x30/0x500 [ 740.961708] RSP: 0018:ffff88013a247e08 EFLAGS: 00010086 [ 740.961730] RAX: ffff8800b912b400 RBX: ffff88013a61e680 RCX: ffff8800b912b400 [ 740.961757] RDX: ffff8800b912b600 RSI: ffff8800b912b600 RDI: ffff88013a61e680 [ 740.961782] RBP: ffff88013a247e48 R08: ffff88013a246000 R09: 000000000002c09d [ 740.961808] R10: 000000000000010f R11: 0000000000000000 R12: ffff88013b00cc00 [ 740.961833] R13: 0000000000000000 R14: ffff88013b00cf80 R15: ffff88013a61e6b0 [ 740.961861] FS: 0000000000000000(0000) GS:ffff88013fc00000(0000) knlGS:0000000000000000 [ 740.961893] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 740.962001] CR2: 00000000000000b8 CR3: 00000000b24fe000 CR4: 00000000000407f0 [ 740.962001] Stack: [ 740.962001] 0000000000000008 ffff8800b912b600 ffff88013b00cc00 ffff88013a61e680 [ 740.962001] ffff88013b00cc00 ffff88013b00cc18 ffff88013b00cf80 ffff88013a61e6b0 [ 740.962001] ffff88013a247eb8 ffffffff810639c6 0000000000012a80 ffff88013a247fd8 [ 740.962001] Call Trace: [ 740.962001] [<ffffffff810639c6>] worker_thread+0x206/0x3f0 [ 740.962001] [<ffffffff810637c0>] ? manage_workers+0x2c0/0x2c0 [ 740.962001] [<ffffffff81069656>] kthread+0xc6/0xd0 [ 740.962001] [<ffffffff81069590>] ? kthread_freezable_should_stop+0x70/0x70 [ 740.962001] [<ffffffff81722ffc>] ret_from_fork+0x7c/0xb0 [ 740.962001] [<ffffffff81069590>] ? kthread_freezable_should_stop+0x70/0x70 [ 740.962001] Code: 89 e5 41 57 41 56 41 55 45 31 ed 41 54 53 48 89 fb 48 83 ec 18 48 8b 06 4c 8b 67 48 48 89 c1 30 c9 a8 04 4c 0f 45 e9 80 7f 58 00 <49> 8b 45 08 44 8b b0 00 01 00 00 78 0c 41 f6 44 24 10 04 0f 84 [ 740.962001] RIP [<ffffffff81062570>] process_one_work+0x30/0x500 [ 740.962001] RSP <ffff88013a247e08> [ 740.962001] CR2: 0000000000000008 [ 740.962001] ---[ end trace 39181460000748de ]--- [ 740.962001] Kernel panic - not syncing: Fatal exception This can happen if there are some stripes left, fewer than MAX_STRIPE_BATCH. A worker is queued to handle them. But before calling raid5_do_work, raid5d handles those stripes making conf->active_stripe = 0. So mddev_suspend() can return. We might then free old worker resources before the queued raid5_do_work() handled them. When it runs, it crashes. raid5d() raid5_store_group_thread_cnt() queue_work mddev_suspend() handle_strips active_stripe=0 free(old worker resources) process_one_work raid5_do_work To avoid this, we should only flush the worker resources before freeing them. This fixes a bug introduced in 3.12 so is suitable for the 3.12.x stable series. Cc: stable@vger.kernel.org (3.12) Fixes: b721420e87 Signed-off-by: Jianpeng Ma <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Shaohua Li <shli@kernel.org>		2013-11-19 15:19:18 +11:00
..
accessibility
acpi	Merge branch 'linus' into sched/core	2013-11-01 08:24:41 +01:00
amba
ata	Merge branch 'for-3.12-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata	2013-10-22 08:21:34 +01:00
atm
auxdisplay
base	devres: restore zeroing behavior of devres_alloc()	2013-10-25 05:46:27 +01:00
bcma	Merge 3.12-rc6 into driver-core-next	2013-10-19 13:05:38 -07:00
block	Via Paul Walmsley <paul@pwsan.com>:	2013-10-28 14:39:03 -07:00
bluetooth	Bluetooth: btusb: Add support for Belkin F8065bf	2013-09-23 17:44:25 -03:00
bus	ARM: driver updates for 3.13	2013-11-11 17:05:37 +09:00
cdrom
char	Merge 3.12-rc6 into char-misc-next	2013-10-19 13:02:47 -07:00
clk	ARM: SoC DT updates for 3.13	2013-11-11 17:34:56 +09:00
clocksource	clocksource: em_sti: Set cpu_possible_mask to fix SMP broadcast	2013-09-26 02:31:04 +02:00
connector	connector: use 'size' everywhere in cn_netlink_send()	2013-10-02 16:03:50 -04:00
cpufreq	ARM: SoC platform changes for 3.13	2013-11-11 16:49:45 +09:00
cpuidle	cpuidle: calxeda: add support to use PSCI calls	2013-10-01 16:30:56 -05:00
crypto
dca
devfreq
dio
dma	ARM: driver updates for 3.13	2013-11-11 17:05:37 +09:00
edac
eisa
extcon	Update extcon for 3.13	2013-09-26 20:47:25 -07:00
firewire
firmware
fmc
gpio	ARM: SoC DT updates for 3.13	2013-11-11 17:34:56 +09:00
gpu	i915: fix compiler warning	2013-10-31 15:28:23 -07:00
hid	Staging driver update for 3.13-rc1	2013-11-07 15:07:58 +09:00
hsi	hsi: convert bus code to use dev_groups	2013-10-16 18:36:04 -07:00
hv	Drivers: hv: vmbus: Fix a bug in channel rescind code	2013-10-19 19:53:46 -07:00
hwmon	hwmon: (applesmc) Always read until end of data	2013-10-09 09:48:55 -07:00
hwspinlock
i2c	i2c: i2c-mux-pinctrl: use deferred probe when adapter not found	2013-10-10 10:22:35 +02:00
ide	ARM: SoC cleanups for 3.13	2013-11-11 16:42:43 +09:00
idle	sched, idle: Fix the idle polling state logic	2013-09-25 13:53:10 +02:00
iio	iio: light: vcnl4000: Remove redundant code	2013-10-24 14:48:14 +01:00
infiniband	Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending	2013-10-27 10:16:33 -07:00
input	ARM: SoC cleanups for 3.13	2013-11-11 16:42:43 +09:00
iommu	x86, build, pci: Fix PCI_MSI build on !SMP	2013-10-04 10:43:34 -07:00
ipack	ipack: convert bus code to use dev_groups	2013-10-16 18:40:57 -07:00
irqchip	Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2013-11-12 10:02:59 +09:00
isdn
leds
lguest
macintosh
mailbox
md	md/raid5: Before freeing old multi-thread worker, it should flush them.	2013-11-19 15:19:18 +11:00
media	ARM: SoC cleanups for 3.13	2013-11-11 16:42:43 +09:00
memory
memstick	memstick: convert bus code to use dev_groups	2013-10-16 18:40:58 -07:00
message	i2o: convert bus code to use dev_groups	2013-10-16 18:40:58 -07:00
mfd	mfd: dbx500: Remove any mention of the BML8580CLK	2013-09-26 11:04:16 +02:00
misc	Driver Core / sysfs patches for 3.13-rc1	2013-11-07 11:42:15 +09:00
mmc	Merge 3.12-rc6 into driver-core-next	2013-10-19 13:05:38 -07:00
mtd	Driver Core / sysfs patches for 3.13-rc1	2013-11-07 11:42:15 +09:00
net	Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus	2013-11-08 08:32:58 +09:00
nfc
ntb
nubus
of	Revert "drivers: of: add initialization code for dma reserved memory"	2013-10-15 09:26:07 +01:00
oprofile
parisc
parport
pci	ARM: driver updates for 3.13	2013-11-11 17:05:37 +09:00
pcmcia	Driver Core / sysfs patches for 3.13-rc1	2013-11-07 11:42:15 +09:00
phy	usb: patches for v3.13	2013-10-24 16:18:40 +01:00
pinctrl	pinctrl: single: Fix build when not built on ARM	2013-10-18 16:43:06 -07:00
platform	platform/x86: fix asus-wmi build error	2013-10-23 07:57:57 +01:00
pnp	PNP: convert bus code to use dev_groups	2013-10-16 18:36:02 -07:00
power
pps
ps3
ptp
pwm
rapidio	rapidio: convert bus code to use dev_groups	2013-10-16 18:36:03 -07:00
regulator	Merge remote-tracking branch 'regulator/fix/wm8350' into regulator-linus	2013-09-30 12:04:33 +01:00
remoteproc
reset
rpmsg
rtc	HID RTC: Open sensor hub open close	2013-10-01 22:06:15 +01:00
s390	s390/scm_blk: fix endless loop for requests != REQ_TYPE_FS	2013-11-06 14:32:22 +01:00
sbus
scsi	Driver Core / sysfs patches for 3.13-rc1	2013-11-07 11:42:15 +09:00
sfi
sh
sn
spi	Merge remote-tracking branch 'spi/fix/s3c64xx' into spi-linus	2013-10-07 14:51:59 +01:00
ssb	ssb: convert bus code to use dev_groups	2013-10-16 18:36:03 -07:00
staging	Staging driver update for 3.13-rc1	2013-11-07 15:07:58 +09:00
target	target/pscsi: fix return value check	2013-10-25 10:42:09 -07:00
tc
thermal	Merge branch 'x86_pkg_temp' of .git into for-rc	2013-10-21 11:26:45 +08:00
tty	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux	2013-11-08 08:24:38 +09:00
uio	Char/Misc patches for 3.13-rc1	2013-11-07 09:41:06 +09:00
usb	ARM: SoC DT updates for 3.13	2013-11-11 17:34:56 +09:00
uwb	Driver Core / sysfs patches for 3.13-rc1	2013-11-07 11:42:15 +09:00
vfio	VFIO: vfio_iommu_type1: fix bug caused by break in nested loop	2013-10-11 10:40:46 -06:00
vhost	vhost/scsi: Fix incorrect usage of get_user_pages_fast write parameter	2013-10-25 11:03:34 -07:00
video	Merge branch 'parisc-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux	2013-11-11 18:15:25 +09:00
virt
virtio	virtio: convert bus code to use dev_groups	2013-10-16 18:40:57 -07:00
vlynq
vme
w1	w1-gpio: Use devm_* functions	2013-10-29 16:58:18 -07:00
watchdog	watchdog: sunxi: Fix section mismatch	2013-10-13 20:02:03 +02:00
xen	xenbus: convert bus code to use dev_groups	2013-10-16 18:36:03 -07:00
zorro
Kconfig	drivers: phy: add generic PHY framework	2013-09-27 17:35:41 -07:00
Makefile	drivers: phy: add generic PHY framework	2013-09-27 17:35:41 -07:00