* Kenji Kaneshige <kaneshige.kenji@xxxxxxxxxxxxxx>: > Alex Chiang wrote: >> We're getting close to the new merge window, and I _think_ this >> patch series is ready for consideration. Notably: >> >> - multiple rescans/removes of devices with and without bridges >> - verified that resource allocation after multiple remove/rescan >> cycles is the same as what we had during initial boot >> - fixes the complete suckage of fakephp (that I created) >> - doesn't affect existing hotplug drivers >> - tested on x86 and ia64 platforms >> >> Please review, and consider testing. For testing ease, you can pull >> from my git branch: >> >> git://git.kernel.org/pub/scm/linux/kernel/git/achiang/pci-hotplug.git >> branch 'test-20090318' is what you want >> > > I got the following oops when I did > > # echo 1 > remove > > on the bridge device. > > [ 6639.239164] ============================================= > [ 6639.239191] [ INFO: possible recursive locking detected ] > [ 6639.239212] 2.6.29-rc8-kk #1 > [ 6639.239227] --------------------------------------------- > [ 6639.239243] events/8/60 is trying to acquire lock: > [ 6639.239252] (events){--..}, at: [<ffffffff80257fc0>] flush_workqueue+0x0/0xa0 > [ 6639.239252] > [ 6639.239252] but task is already holding lock: > [ 6639.239252] (events){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 > [ 6639.239252] > [ 6639.239252] other info that might help us debug this: > [ 6639.239252] 3 locks held by events/8/60: > [ 6639.239252] #0: (events){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 > [ 6639.239252] #1: (&ss->work){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 > [ 6639.239252] #2: (pci_remove_rescan_mutex){--..}, at: [<ffffffff803c05b9>] remove_callback+0x29/0x80 > [ 6639.239252] > [ 6639.239252] stack backtrace: > [ 6639.239252] Pid: 60, comm: events/8 Not tainted 2.6.29-rc8-kk #1 > [ 6639.239252] Call Trace: > [ 6639.239252] [<ffffffff8026dfcd>] validate_chain+0xb7d/0x1260 > [ 6639.239252] [<ffffffff8026eade>] __lock_acquire+0x42e/0xa40 > [ 6639.239252] [<ffffffff8026f148>] lock_acquire+0x58/0x80 > [ 6639.239252] [<ffffffff80257fc0>] ? flush_workqueue+0x0/0xa0 > [ 6639.239252] [<ffffffff8025800d>] flush_workqueue+0x4d/0xa0 > [ 6639.239252] [<ffffffff80257fc0>] ? flush_workqueue+0x0/0xa0 > [ 6639.239252] [<ffffffff80258070>] flush_scheduled_work+0x10/0x20 > [ 6639.239252] [<ffffffffa0158065>] e1000_remove+0x55/0xfe [e1000e] > [ 6639.239252] [<ffffffff8033ee60>] ? sysfs_schedule_callback_work+0x0/0x50 > [ 6639.239252] [<ffffffff803bf7a2>] pci_device_remove+0x32/0x70 > [ 6639.239252] [<ffffffff80441409>] __device_release_driver+0x59/0x90 > [ 6639.241006] [<ffffffff8044153b>] device_release_driver+0x2b/0x40 > [ 6639.241006] [<ffffffff80441036>] bus_remove_device+0xa6/0x120 > [ 6639.241006] [<ffffffff8043dacb>] device_del+0x12b/0x190 > [ 6639.241006] [<ffffffff8043db56>] device_unregister+0x26/0x70 > [ 6639.241006] [<ffffffff803ba529>] pci_stop_dev+0x49/0x60 > [ 6639.241006] [<ffffffff803ba670>] pci_remove_bus_device+0x40/0xc0 > [ 6639.241006] [<ffffffff803ba71d>] pci_remove_behind_bridge+0x2d/0x50 > [ 6639.241006] [<ffffffff803ba64e>] pci_remove_bus_device+0x1e/0xc0 > [ 6639.241006] [<ffffffff803c05c8>] remove_callback+0x38/0x80 > [ 6639.241006] [<ffffffff8033ee7f>] sysfs_schedule_callback_work+0x1f/0x50 > [ 6639.241006] [<ffffffff8025769a>] run_workqueue+0x15a/0x230 > [ 6639.241006] [<ffffffff80257648>] ? run_workqueue+0x108/0x230 > [ 6639.241006] [<ffffffff8025846f>] worker_thread+0x9f/0x100 > [ 6639.241006] [<ffffffff8025bce0>] ? autoremove_wake_function+0x0/0x40 > [ 6639.241006] [<ffffffff802583d0>] ? worker_thread+0x0/0x100 > [ 6639.241006] [<ffffffff8025b89d>] kthread+0x4d/0x80 > [ 6639.241006] [<ffffffff8020d4ba>] child_rip+0xa/0x20 > [ 6639.241006] [<ffffffff8020cebc>] ? restore_args+0x0/0x30 > [ 6639.241006] [<ffffffff8025b850>] ? kthread+0x0/0x80 > [ 6639.241006] [<ffffffff8020d4b0>] ? child_rip+0x0/0x20 > [ 6639.283330] e1000e 0000:40:00.0: PCI INT A disabled > [ 6639.324332] e1000e 0000:40:00.1: PCI INT B disabled > [ 6639.325031] aer 0000:2f:04.0:pcie22: unloading service driver aer pci_device_remove() calls the driver's ->remove method directly; it shouldn't be messing around with that sysfs callback. Does this only happen with e1000e devices? Or does it happen on any bridge device? I am stumped; I've never seen this locking issue before... Will continue to look, thanks. /ac -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html