Vivien Didelot 762eb67bc2 net: dsa: mv88e6xxx: fix circular lock in PPU work ... Lock debugging shows that there is a possible circular lock in the PPU work code. Switch the lock order of smi_mutex and ppu_mutex to fix this. Here's the full trace: [ 4.341325] ====================================================== [ 4.347519] [ INFO: possible circular locking dependency detected ] [ 4.353800] 4.6.0 #4 Not tainted [ 4.357039] ------------------------------------------------------- [ 4.363315] kworker/0:1/328 is trying to acquire lock: [ 4.368463] (&ps->smi_mutex){+.+.+.}, at: [<8049c758>] mv88e6xxx_reg_read+0x30/0x54 [ 4.376313] [ 4.376313] but task is already holding lock: [ 4.382160] (&ps->ppu_mutex){+.+...}, at: [<8049cac0>] mv88e6xxx_ppu_reenable_work+0x28/0xd4 [ 4.390772] [ 4.390772] which lock already depends on the new lock. [ 4.390772] [ 4.398963] [ 4.398963] the existing dependency chain (in reverse order) is: [ 4.406461] [ 4.406461] -> #1 (&ps->ppu_mutex){+.+...}: [ 4.410897] [<806d86bc>] mutex_lock_nested+0x54/0x360 [ 4.416606] [<8049a800>] mv88e6xxx_ppu_access_get+0x28/0x100 [ 4.422906] [<8049b778>] mv88e6xxx_phy_read+0x90/0xdc [ 4.428599] [<806a4534>] dsa_slave_phy_read+0x3c/0x40 [ 4.434300] [<804943ec>] mdiobus_read+0x68/0x80 [ 4.439481] [<804939d4>] get_phy_device+0x58/0x1d8 [ 4.444914] [<80493ed0>] mdiobus_scan+0x24/0xf4 [ 4.450078] [<8049409c>] __mdiobus_register+0xfc/0x1ac [ 4.455857] [<806a40b0>] dsa_probe+0x860/0xca8 [ 4.460934] [<8043246c>] platform_drv_probe+0x5c/0xc0 [ 4.466627] [<804305a0>] driver_probe_device+0x118/0x450 [ 4.472589] [<80430b00>] __device_attach_driver+0xac/0x128 [ 4.478724] [<8042e350>] bus_for_each_drv+0x74/0xa8 [ 4.484235] [<804302d8>] __device_attach+0xc4/0x154 [ 4.489755] [<80430cec>] device_initial_probe+0x1c/0x20 [ 4.495612] [<8042f620>] bus_probe_device+0x98/0xa0 [ 4.501123] [<8042fbd0>] deferred_probe_work_func+0x4c/0xd4 [ 4.507328] [<8013a794>] process_one_work+0x1a8/0x604 [ 4.513030] [<8013ac54>] worker_thread+0x64/0x528 [ 4.518367] [<801409e8>] kthread+0xec/0x100 [ 4.523201] [<80108f30>] ret_from_fork+0x14/0x24 [ 4.528462] [ 4.528462] -> #0 (&ps->smi_mutex){+.+.+.}: [ 4.532895] [<8015ad5c>] lock_acquire+0xb4/0x1dc [ 4.538154] [<806d86bc>] mutex_lock_nested+0x54/0x360 [ 4.543856] [<8049c758>] mv88e6xxx_reg_read+0x30/0x54 [ 4.549549] [<8049cad8>] mv88e6xxx_ppu_reenable_work+0x40/0xd4 [ 4.556022] [<8013a794>] process_one_work+0x1a8/0x604 [ 4.561707] [<8013ac54>] worker_thread+0x64/0x528 [ 4.567053] [<801409e8>] kthread+0xec/0x100 [ 4.571878] [<80108f30>] ret_from_fork+0x14/0x24 [ 4.577139] [ 4.577139] other info that might help us debug this: [ 4.577139] [ 4.585159] Possible unsafe locking scenario: [ 4.585159] [ 4.591093] CPU0 CPU1 [ 4.595631] ---- ---- [ 4.600169] lock(&ps->ppu_mutex); [ 4.603693] lock(&ps->smi_mutex); [ 4.609742] lock(&ps->ppu_mutex); [ 4.615790] lock(&ps->smi_mutex); [ 4.619314] [ 4.619314] *** DEADLOCK *** [ 4.619314] [ 4.625256] 3 locks held by kworker/0:1/328: [ 4.629537] #0: ("events"){.+.+..}, at: [<8013a704>] process_one_work+0x118/0x604 [ 4.637288] #1: ((&ps->ppu_work)){+.+...}, at: [<8013a704>] process_one_work+0x118/0x604 [ 4.645653] #2: (&ps->ppu_mutex){+.+...}, at: [<8049cac0>] mv88e6xxx_ppu_reenable_work+0x28/0xd4 [ 4.654714] [ 4.654714] stack backtrace: [ 4.659098] CPU: 0 PID: 328 Comm: kworker/0:1 Not tainted 4.6.0 #4 [ 4.665286] Hardware name: Freescale Vybrid VF5xx/VF6xx (Device Tree) [ 4.671748] Workqueue: events mv88e6xxx_ppu_reenable_work [ 4.677174] Backtrace: [ 4.679674] [<8010d354>] (dump_backtrace) from [<8010d5a0>] (show_stack+0x20/0x24) [ 4.687252] r6:80fb3c88 r5:80fb3c88 r4:80fb4728 r3:00000002 [ 4.693003] [<8010d580>] (show_stack) from [<803b45e8>] (dump_stack+0x24/0x28) [ 4.700246] [<803b45c4>] (dump_stack) from [<80157398>] (print_circular_bug+0x208/0x32c) [ 4.708361] [<80157190>] (print_circular_bug) from [<8015a630>] (__lock_acquire+0x185c/0x1b80) [ 4.716982] r10:9ec22a00 r9:00000060 r8:8164b6bc r7:00000040 r6:00000003 r5:8163a5b4 [ 4.724905] r4:00000003 r3:9ec22de8 [ 4.728537] [<80158dd4>] (__lock_acquire) from [<8015ad5c>] (lock_acquire+0xb4/0x1dc) [ 4.736378] r10:60000013 r9:00000000 r8:00000000 r7:00000000 r6:9e5e9c50 r5:80e618e0 [ 4.744301] r4:00000000 [ 4.746879] [<8015aca8>] (lock_acquire) from [<806d86bc>] (mutex_lock_nested+0x54/0x360) [ 4.754976] r10:9e5e9c1c r9:80e616c4 r8:9f685ea0 r7:0000001b r6:9ec22a00 r5:8163a5b4 [ 4.762899] r4:9e5e9c1c [ 4.765477] [<806d8668>] (mutex_lock_nested) from [<8049c758>] (mv88e6xxx_reg_read+0x30/0x54) [ 4.774008] r10:80e60c5b r9:80e616c4 r8:9f685ea0 r7:0000001b r6:00000004 r5:9e5e9c10 [ 4.781930] r4:9e5e9c1c [ 4.784507] [<8049c728>] (mv88e6xxx_reg_read) from [<8049cad8>] (mv88e6xxx_ppu_reenable_work+0x40/0xd4) [ 4.793907] r7:9ffd5400 r6:9e5e9c68 r5:9e5e9cb0 r4:9e5e9c10 [ 4.799659] [<8049ca98>] (mv88e6xxx_ppu_reenable_work) from [<8013a794>] (process_one_work+0x1a8/0x604) [ 4.809059] r9:80e616c4 r8:9f685ea0 r7:9ffd5400 r6:80e0a1c8 r5:9f5f2e80 r4:9e5e9cb0 [ 4.816910] [<8013a5ec>] (process_one_work) from [<8013ac54>] (worker_thread+0x64/0x528) [ 4.825010] r10:9f5f2e80 r9:00000008 r8:80e0dc80 r7:80e0a1fc r6:80e0a1c8 r5:9f5f2e98 [ 4.832933] r4:80e0a1c8 [ 4.835510] [<8013abf0>] (worker_thread) from [<801409e8>] (kthread+0xec/0x100) [ 4.842827] r10:00000000 r9:00000000 r8:00000000 r7:8013abf0 r6:9f5f2e80 r5:9ec15740 [ 4.850749] r4:00000000 [ 4.853327] [<801408fc>] (kthread) from [<80108f30>] (ret_from_fork+0x14/0x24) [ 4.860557] r7:00000000 r6:00000000 r5:801408fc r4:9ec15740 Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2016-06-04 14:29:52 -07:00
..
accessibility	…
acpi	remove lots of IS_ERR_VALUE abuses	2016-05-27 15:26:11 -07:00
amba	…
android	…
ata	remove lots of IS_ERR_VALUE abuses	2016-05-27 15:26:11 -07:00
atm	atm: iphase: off by one in rx_pkt()	2016-05-31 11:52:59 -07:00
auxdisplay	…
base	More power management updates for v4.7-rc1	2016-05-25 15:29:21 -07:00
bcma	MTD updates for v4.7:	2016-05-24 11:00:20 -07:00
block	DAX error handling for 4.7	2016-05-26 19:34:26 -07:00
bluetooth	Bluetooth: Add USB ID 13D3:3487 to ath3k	2016-05-13 16:54:59 +02:00
bus	Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus	2016-05-19 10:02:26 -07:00
cdrom	…
char	Merge branch 'akpm' (patches from Andrew)	2016-05-20 22:31:33 -07:00
clk	remove lots of IS_ERR_VALUE abuses	2016-05-27 15:26:11 -07:00
clocksource	Small release overall.	2016-05-19 11:27:09 -07:00
connector	…
cpufreq	remove lots of IS_ERR_VALUE abuses	2016-05-27 15:26:11 -07:00
cpuidle	cpuidle: Fix cpuidle_state_is_coupled() argument in cpuidle_enter()	2016-05-18 02:48:37 +02:00
crypto	Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6	2016-05-30 15:20:18 -07:00
dax	/dev/dax, core: file operations and dax-mmap	2016-05-20 22:02:55 -07:00
dca	…
devfreq	…
dio	…
dma	remove lots of IS_ERR_VALUE abuses	2016-05-27 15:26:11 -07:00
dma-buf	…
edac	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2016-05-17 17:05:30 -07:00
eisa	…
extcon	…
firewire	…
firmware	driver core update for 4.7-rc1	2016-05-20 21:26:15 -07:00
fmc	…
fpga	…
gpio	gpio: drop lock before reading GPIO direction	2016-05-30 17:11:59 +02:00
gpu	remove lots of IS_ERR_VALUE abuses	2016-05-27 15:26:11 -07:00
hid	Merge branch 'for-4.7/wacom' into for-linus	2016-05-17 12:42:27 +02:00
hsi	…
hv	…
hwmon	Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging	2016-05-26 09:48:23 -07:00
hwspinlock	drivers/hwspinlock: use correct radix tree API	2016-05-20 17:58:30 -07:00
hwtracing	Char / Misc driver update for 4.7-rc1	2016-05-20 21:20:31 -07:00
i2c	i2c: dev: use after free in detach	2016-05-28 17:37:42 +02:00
ide	…
idle	…
iio	Staging and IIO driver update for 4.7-rc1	2016-05-20 22:20:48 -07:00
infiniband	Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending	2016-05-28 12:04:17 -07:00
input	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input	2016-05-27 19:14:35 -07:00
iommu	remove lots of IS_ERR_VALUE abuses	2016-05-27 15:26:11 -07:00
ipack	…
irqchip	Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus	2016-05-28 16:41:39 -07:00
isdn	TTY and Serial driver update for 4.7-rc1	2016-05-20 20:57:27 -07:00
leds	pwm: Changes for v4.7-rc1	2016-05-25 10:40:15 -07:00
lguest	…
lightnvm	…
macintosh	…
mailbox	…
mcb	…
md	Merge branch 'for-linus' of git://git.kernel.dk/linux-block	2016-05-27 14:28:09 -07:00
media	Merge branch 'hash' of git://ftp.sciencehorizons.net/linux	2016-05-28 16:15:25 -07:00
memory	MTD updates for v4.7:	2016-05-24 11:00:20 -07:00
memstick	drivers/memstick/core/mspro_block: use kmemdup	2016-05-23 17:04:14 -07:00
message	SCSI misc on 20160517	2016-05-18 16:38:59 -07:00
mfd	remove lots of IS_ERR_VALUE abuses	2016-05-27 15:26:11 -07:00
misc	Char / Misc driver update for 4.7-rc1	2016-05-20 21:20:31 -07:00
mmc	remove lots of IS_ERR_VALUE abuses	2016-05-27 15:26:11 -07:00
mtd	This pull request contains mostly cleanups and minor	2016-05-27 18:49:29 -07:00
net	net: dsa: mv88e6xxx: fix circular lock in PPU work	2016-06-04 14:29:52 -07:00
nfc	…
ntb	…
nubus	…
nvdimm	DAX error handling for 4.7	2016-05-26 19:34:26 -07:00
nvme	nvme/host: Add missing blk_integrity tag_size + flags assignments	2016-05-17 17:14:21 -06:00
nvmem	remove lots of IS_ERR_VALUE abuses	2016-05-27 15:26:11 -07:00
of	MTD updates for v4.7:	2016-05-24 11:00:20 -07:00
oprofile	…
parisc	…
parport	…
pci	Char / Misc driver update for 4.7-rc1	2016-05-20 21:20:31 -07:00
pcmcia	…
perf	…
phy	USB patches for 4.7-rc1	2016-05-20 21:12:25 -07:00
pinctrl	drivers/pinctrl/intel/pinctrl-baytrail.c: fix build with gcc-4.4	2016-05-26 15:35:44 -07:00
platform	platform/chrome: Driver and binding changes for 4.7	2016-05-28 12:32:01 -07:00
pnp	driver core update for 4.7-rc1	2016-05-20 21:26:15 -07:00
power	power supply and reset changes for the v4.7 series	2016-05-20 14:06:21 -07:00
powercap	Power management material for v4.7-rc1	2016-05-16 19:17:22 -07:00
pps	…
ps3	…
ptp	ptp: oops in ptp_ioctl()	2016-05-29 22:32:27 -07:00
pwm	pwm: Changes for v4.7-rc1	2016-05-25 10:40:15 -07:00
rapidio	…
ras	…
regulator	regulator: pwm: Use pwm_get_args() where appropriate	2016-05-17 14:45:02 +02:00
remoteproc	remoteproc: Add additional crash reasons	2016-05-12 15:50:19 -07:00
reset	…
rpmsg	…
rtc	rtc: tps6586x: rename so module can be autoloaded	2016-05-21 17:07:17 +02:00
s390	DAX error handling for 4.7	2016-05-26 19:34:26 -07:00
sbus	openprom: fix warning	2016-05-20 18:33:37 -07:00
scsi	SCSI fixes on 20160529	2016-05-29 13:28:39 -07:00
sfi	…
sh	…
sn	…
soc	soc: mtk-pmic-wrap: avoid integer overflow warning	2016-05-19 15:20:24 +02:00
spi	sound updates #2 for 4.7-rc1	2016-05-28 12:23:12 -07:00
spmi	…
ssb	…
staging	Round two of 4.7 merge window patches	2016-05-28 11:04:16 -07:00
target	Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending	2016-05-28 12:04:17 -07:00
tc	…
thermal	Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux	2016-05-26 09:23:43 -07:00
thunderbolt	…
tty	remove lots of IS_ERR_VALUE abuses	2016-05-27 15:26:11 -07:00
uio	…
usb	Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending	2016-05-28 12:04:17 -07:00
uwb	…
vfio	VFIO updates for v4.7-rc1	2016-05-25 09:47:26 -07:00
vhost	…
video	remove lots of IS_ERR_VALUE abuses	2016-05-27 15:26:11 -07:00
virt	…
virtio	virtio_balloon: fix PFN format for virtio-1	2016-05-22 19:44:13 +03:00
vlynq	…
vme	…
w1	…
watchdog	Merge git://www.linux-watchdog.org/linux-watchdog	2016-05-25 10:19:17 -07:00
xen	Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending	2016-05-28 12:04:17 -07:00
zorro	…
Kconfig	libnvdimm for 4.7	2016-05-23 11:18:01 -07:00
Makefile	/dev/dax, pmem: direct access to persistent memory	2016-05-20 22:02:53 -07:00