A trip through usb_hcd_pci_remove produces:
BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:993
in_atomic(): 0, irqs_disabled(): 1, pid: 4752, name: bash
INFO: lockdep is turned off.
irq event stamp: 0
hardirqs last enabled at (0): [< (null)>] (null)
hardirqs last disabled at (0): [<ffffffff8108da9d>] copy_process.part.36+0x64d/0x2380
softirqs last enabled at (0): [<ffffffff8108da9d>] copy_process.part.36+0x64d/0x2380
softirqs last disabled at (0): [< (null)>] (null)
CPU: 1 PID: 4752 Comm: bash Tainted: G W I 4.9.0debug-rt16+ #2
Hardware name: Stratus ftServer 2700/G7LAY, BIOS BIOS Version 6.3:58 09/18/2014
ffffc90006e5fbd0 ffffffff813d243a ffff88016ac0b240 0000000000001290
ffffc90006e5fbf8 ffffffff810c6907 ffff8801682f45d0 ffff8801682f1000
ffff8801682f45d0 ffffc90006e5fc18 ffffffff817dee44 ffff88016b2aee18
Call Trace:
[<ffffffff813d243a>] dump_stack+0x99/0xcf
[<ffffffff810c6907>] ___might_sleep+0x137/0x210
[<ffffffff817dee44>] rt_spin_lock+0x24/0x60
[<ffffffff815b526f>] ehci_irq+0x2f/0x400
[<ffffffff814226b9>] ? pci_bus_read_config_word+0x99/0xb0
[<ffffffff81592d66>] usb_hcd_irq+0x26/0x40
[<ffffffff815a7a90>] usb_hcd_pci_remove+0x50/0x170
[<ffffffff815b933a>] ehci_pci_remove+0x1a/0x20
[<ffffffff8142fc39>] pci_device_remove+0x39/0xc0
[<ffffffff8152c4da>] __device_release_driver+0x9a/0x150
[<ffffffff8152c5b3>] device_release_driver+0x23/0x30
[<ffffffff81427f6c>] pci_stop_bus_device+0x8c/0xa0
[<ffffffff8142808a>] pci_stop_and_remove_bus_device_locked+0x1a/0x30
[<ffffffff8143182c>] remove_store+0x7c/0x90
[<ffffffff81526508>] dev_attr_store+0x18/0x30
[<ffffffff81313444>] sysfs_kf_write+0x44/0x60
[<ffffffff81312d7c>] kernfs_fop_write+0x13c/0x1d0
[<ffffffff81279bb7>] __vfs_write+0x37/0x160
[<ffffffff81118c82>] ? rcu_sync_lockdep_assert+0x12/0x60
[<ffffffff8127e3c6>] ? __sb_start_write+0x176/0x260
[<ffffffff8127a3f4>] ? vfs_write+0x184/0x1b0
[<ffffffff8127a325>] vfs_write+0xb5/0x1b0
[<ffffffff810025e0>] ? syscall_trace_enter+0x1d0/0x380
[<ffffffff8127b7e8>] SyS_write+0x58/0xc0
[<ffffffff81002d0a>] do_syscall_64+0x7a/0x230
[<ffffffff817df6c9>] entry_SYSCALL64_slow_path+0x25/0x25
Repro via something like:
> echo 1 > /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/0000:02:01.0/0000:3d:00.0/0000:3e:01.0/0000:66:00.0/remove
Switching usb_hcd_pci_remove to use _nort variants prevents the BUG.
Signed-off-by: Nate Dailey <nate.dailey@xxxxxxxxxxx>
---
drivers/usb/core/hcd-pci.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c
index 7859d738df41..e9e7307028bc 100644
--- a/drivers/usb/core/hcd-pci.c
+++ b/drivers/usb/core/hcd-pci.c
@@ -341,9 +341,9 @@ void usb_hcd_pci_remove(struct pci_dev *dev)
* to test whether the controller hardware has been removed (e.g.,
* cardbus physical eject).
*/
- local_irq_disable();
+ local_irq_disable_nort();
usb_hcd_irq(0, hcd);
- local_irq_enable();
+ local_irq_enable_nort();
/* Note: dev_set_drvdata must be called while holding the rwsem */
if (dev->class == CL_EHCI) {
--
2.11.0
--
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