Rob Clark 3e8b554114 soc: qcom: smsm: fix of_node refcnting problem ... of_find_node_with_property() drops the reference to the 'from' node, which eventually (after enough -EPROBE_DEFERs) drops the last reference to the node causing all sorts of fun problems, and this nice splat. BUG: sleeping function called from invalid context at ../kernel/locking/mutex.c:747 in_atomic(): 1, irqs_disabled(): 128, pid: 33, name: kworker/0:1 4 locks held by kworker/0:1/33: #0: ("events"){.+.+.+}, at: [<ffff0000080fa91c>] process_one_work+0x1a4/0x728 #1: (deferred_probe_work){+.+.+.}, at: [<ffff0000080fa91c>] process_one_work+0x1a4/0x728 #2: (&dev->mutex){......}, at: [<ffff000008676078>] __device_attach+0x30/0x168 #3: (devtree_lock){......}, at: [<ffff000008828fd0>] of_find_node_with_property+0x30/0xe0 irq event stamp: 18976 hardirqs last enabled at (18975): [<ffff00000815794c>] __down_trylock_console_sem+0x74/0xb8 hardirqs last disabled at (18976): [<ffff0000089e26d4>] _raw_spin_lock_irqsave+0x2c/0x78 softirqs last enabled at (16880): [<ffff0000080e0f00>] __do_softirq+0x580/0x640 softirqs last disabled at (16871): [<ffff0000080e13a4>] irq_exit+0xe4/0x138 CPU: 0 PID: 33 Comm: kworker/0:1 Tainted: G E 4.12.0-rc5+ #1455 Hardware name: qualcomm dragonboard410c/dragonboard410c, BIOS 2017.07-rc1-00234-g22fa70a-dirty 06/26/2017 Workqueue: events deferred_probe_work_func Call trace: [<ffff000008089ee0>] dump_backtrace+0x0/0x230 [<ffff00000808a134>] show_stack+0x24/0x30 [<ffff0000084e1944>] dump_stack+0xac/0xe8 [<ffff00000810d7e0>] ___might_sleep+0x150/0x230 [<ffff00000810d918>] __might_sleep+0x58/0x90 [<ffff0000089dde18>] __mutex_lock+0x50/0x870 [<ffff0000089de674>] mutex_lock_nested+0x3c/0x50 [<ffff000008388ae0>] kernfs_remove+0x30/0x50 [<ffff00000838b720>] sysfs_remove_dir+0x58/0x70 [<ffff0000084e393c>] kobject_del+0x1c/0x58 [<ffff0000084e374c>] kobject_put+0xb4/0x208 [<ffff00000882c364>] of_node_put+0x24/0x30 [<ffff000008829018>] of_find_node_with_property+0x78/0xe0 [<ffff000000aff5f4>] qcom_smsm_probe+0x194/0x720 [smsm] [<ffff0000086793b4>] platform_drv_probe+0x74/0x110 [<ffff0000086765bc>] driver_probe_device+0x2b4/0x420 [<ffff000008676920>] __device_attach_driver+0xd0/0x150 [<ffff000008673e78>] bus_for_each_drv+0x68/0xa8 [<ffff00000867611c>] __device_attach+0xd4/0x168 [<ffff000008676a1c>] device_initial_probe+0x24/0x30 [<ffff000008675380>] bus_probe_device+0xa0/0xa8 [<ffff000008675948>] deferred_probe_work_func+0xb8/0xf8 [<ffff0000080fa9d4>] process_one_work+0x25c/0x728 [<ffff0000080faef4>] worker_thread+0x54/0x3d8 [<ffff0000081031d8>] kthread+0x110/0x140 [<ffff000008082d90>] ret_from_fork+0x10/0x40 OF: ERROR: Bad of_node_put() on /smsm CPU: 0 PID: 33 Comm: kworker/0:1 Tainted: G W E 4.12.0-rc5+ #1455 Hardware name: qualcomm dragonboard410c/dragonboard410c, BIOS 2017.07-rc1-00234-g22fa70a-dirty 06/26/2017 Workqueue: events deferred_probe_work_func Signed-off-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Andy Gross <andy.gross@linaro.org>		2017-08-08 14:37:42 -05:00
..
Kconfig	soc: qcom: smd: Remove standalone driver	2017-03-28 17:58:07 -07:00
Makefile	soc: qcom: smd: Remove standalone driver	2017-03-28 17:58:07 -07:00
mdt_loader.c	remoteproc: qcom: mdt_loader: Use signed type for offset	2017-02-22 02:07:13 -08:00
qcom_gsbi.c	soc: qcom: gsbi: Add support for ADM CRCI muxing	2015-03-11 15:18:39 -05:00
smd-rpm.c	soc: qcom: smd-rpm: Add msm8996 compatibility	2017-03-28 17:58:08 -07:00
smem_state.c	soc: qcom: Update properties for smem state referencing	2016-06-24 22:53:41 -05:00
smem.c	soc: qcom: smem: Silence probe defer error	2016-08-23 15:46:32 -05:00
smp2p.c	soc: qcom: smp2p: Drop io-accessors	2016-06-24 13:34:00 -05:00
smsm.c	soc: qcom: smsm: fix of_node refcnting problem	2017-08-08 14:37:42 -05:00
spm.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2016-05-17 16:26:30 -07:00
wcnss_ctrl.c	soc: qcom: smd: Transition client drivers from smd to rpmsg	2017-03-28 17:58:07 -07:00