Commit Graph

5 Commits

Author SHA1 Message Date
Johan Hovold
8804517e9f soc: qcom: smsm: fix child-node lookup
Fix child-node lookup during probe, which ended up searching the whole
device tree depth-first starting at the parent rather than just matching
on its children.

Note that the original premature free of the parent node has already
been fixed separately.

Also note that this pattern of looking up the first child node with a
given property is rare enough that a generic helper is probably not
warranted.

Fixes: c97c4090ff ("soc: qcom: smsm: Add driver for Qualcomm SMSM")
Fixes: 3e8b554114 ("soc: qcom: smsm: fix of_node refcnting problem")
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Rob Clark <robdclark@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>
2017-12-20 15:38:34 -06:00
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
Jonathan Neuschäfer
35dfa3efea soc: qcom: smsm: Improve error handling, quiesce probe deferral
Don't use size if info indicates an error condition. Previously a
non-ENOENT error (such as -EPROBE_DEFER) would lead to size being used
even though it hadn't necessarily been initialized in qcom_smem_get.

Don't print an error message in the -EPROBE_DEFER case.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>
2017-06-05 21:50:44 -05:00
Bjorn Andersson
3680a4a974 soc: qcom: Update properties for smem state referencing
Update the property names to match device tree bindings, the correct
values should be qcom,smem-states and qcom,smem-state-names.

Also update the #qcom,smem-state-cells for consistency, before we merge
any users of these properties.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>
2016-06-24 22:53:41 -05:00
Bjorn Andersson
c97c4090ff soc: qcom: smsm: Add driver for Qualcomm SMSM
This driver exposed the Qualcomm Shared Memory State Machine bits.

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Andy Gross <agross@codeaurora.org>
2015-12-08 13:01:01 -06:00