From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nate Dailey Subject: [PATCH] usb: Use _nort in usb_hcd_pci_remove Date: Thu, 20 Apr 2017 14:00:27 -0400 Message-ID: <20170420180027.19316-1-nate.dailey@stratus.com> Mime-Version: 1.0 Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: 8BIT Cc: Nate Dailey To: Return-path: Received: from us-smtp-delivery-131.mimecast.com ([216.205.24.131]:55608 "EHLO us-smtp-delivery-131.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S970193AbdDTSGn (ORCPT ); Thu, 20 Apr 2017 14:06:43 -0400 Received: from EXHQ1.corp.stratus.com (exhq1.corp.stratus.com [134.111.200.125]) by mailhub4.stratus.com (8.12.11/8.12.11) with ESMTP id v3KI0SPZ031777 for ; Thu, 20 Apr 2017 14:00:28 -0400 Sender: linux-rt-users-owner@vger.kernel.org List-ID: 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): [] copy_process.part.36+0x64d/0x2380 softirqs last enabled at (0): [] 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: [] dump_stack+0x99/0xcf [] ___might_sleep+0x137/0x210 [] rt_spin_lock+0x24/0x60 [] ehci_irq+0x2f/0x400 [] ? pci_bus_read_config_word+0x99/0xb0 [] usb_hcd_irq+0x26/0x40 [] usb_hcd_pci_remove+0x50/0x170 [] ehci_pci_remove+0x1a/0x20 [] pci_device_remove+0x39/0xc0 [] __device_release_driver+0x9a/0x150 [] device_release_driver+0x23/0x30 [] pci_stop_bus_device+0x8c/0xa0 [] pci_stop_and_remove_bus_device_locked+0x1a/0x30 [] remove_store+0x7c/0x90 [] dev_attr_store+0x18/0x30 [] sysfs_kf_write+0x44/0x60 [] kernfs_fop_write+0x13c/0x1d0 [] __vfs_write+0x37/0x160 [] ? rcu_sync_lockdep_assert+0x12/0x60 [] ? __sb_start_write+0x176/0x260 [] ? vfs_write+0x184/0x1b0 [] vfs_write+0xb5/0x1b0 [] ? syscall_trace_enter+0x1d0/0x380 [] SyS_write+0x58/0xc0 [] do_syscall_64+0x7a/0x230 [] 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 --- 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