On Sat, 2011-07-02 at 08:08 +0200, Andi Kleen wrote: > > I'm not able to reproduce it on a vanilla 3.0-rc5 system. Can anybody > > give the exact sequence of steps you went through to trigger the bug? > > Connect USB storage device with builtin fake CD rom. Wait for udisk > to mount it. Pull cable. udisk does umount. Oops. > > I also got a log of the refcounting now if you want it. So I've got the log, but this is the relevant section: --- usb 2-1.5: USB disconnect, device number 4 sr 5:0:0:1: scsi put_device 13 from device_del+0x177/0x1c0 sr 5:0:0:1: scsi put_device 12 from bsg_kref_release_function+0x28/0x30 sr 5:0:0:1: scsi put_device 10 from device_del+0x177/0x1c0 sr 5:0:0:1: scsi put_device 8 from device_del+0x177/0x1c0 sr 5:0:0:1: scsi put_device 7 from scsi_device_cls_release+0x15/0x20 sr 5:0:0:1: scsi put_device 6 from klist_children_put+0x12/0x20 sr 5:0:0:1: scsi put_device 5 from klist_devices_put+0x12/0x20 sr 5:0:0:1: scsi put_device 3 from device_del+0x177/0x1c0 scsi: killing requests for dead queue BUG: sleeping function called from invalid context at /home/ak/lsrc/git/linux-2.6/arch/x86/mm/fault.c:1103 in_atomic(): 0, irqs_disabled(): 1, pid: 2527, name: umount Pid: 2527, comm: umount Not tainted 3.0.0-rc5+ #8 Call Trace: [<ffffffff8103af8c>] __might_sleep+0xcc/0xf0 [<ffffffff8155af42>] do_page_fault+0x142/0x4c0 [<ffffffffa01d5385>] ? write_msg+0x105/0x120 [netconsole] [<ffffffff810514f7>] ? __call_console_drivers+0x97/0xb0 [<ffffffff81079692>] ? up+0x32/0x50 [<ffffffff81557f5f>] page_fault+0x1f/0x30 [<ffffffff81389a70>] ? scsi_setup_blk_pc_cmnd+0x170/0x170 [<ffffffff81388e19>] ? scsi_prep_state_check+0x9/0x90 [<ffffffff8138992b>] scsi_setup_blk_pc_cmnd+0x2b/0x170 [<ffffffff81389abd>] scsi_prep_fn+0x4d/0x60 [<ffffffff812847ad>] blk_peek_request+0xbd/0x230 [<ffffffff8138a1ea>] scsi_request_fn+0x44a/0x470 [<ffffffff8127e42b>] __blk_run_queue+0x1b/0x20 [<ffffffff812885a3>] blk_execute_rq_nowait+0x63/0xb0 [<ffffffff81288676>] blk_execute_rq+0x86/0xf0 [<ffffffff8128430d>] ? blk_get_request+0x6d/0xa0 [<ffffffff81389c6c>] scsi_execute+0xfc/0x160 [<ffffffff8138a40a>] scsi_execute_req+0xca/0x140 [<ffffffff81383ea8>] ioctl_internal_command.clone.4+0x68/0x1a0 [<ffffffff81103f82>] ? pagevec_lookup+0x22/0x30 [<ffffffff8138405e>] scsi_set_medium_removal+0x7e/0xb0 [<ffffffff8139b390>] sr_lock_door+0x20/0x30 [<ffffffff813c4d63>] cdrom_release+0xa3/0x260 [<ffffffff8118157e>] ? invalidate_bh_lru+0x2e/0x50 [<ffffffff81181550>] ? buffer_cpu_notify+0xa0/0xa0 [<ffffffff8139a088>] sr_block_release+0x38/0x60 [<ffffffff8118833c>] __blkdev_put+0x16c/0x1b0 [<ffffffff811883b2>] blkdev_put+0x32/0x130 [<ffffffff8115650e>] kill_block_super+0x4e/0x80 [<ffffffff81156865>] deactivate_locked_super+0x45/0x70 [<ffffffff8115724a>] deactivate_super+0x4a/0x70 [<ffffffff81171d54>] mntput_no_expire+0xc4/0x110 [<ffffffff81172a2c>] sys_umount+0x6c/0x360 [<ffffffff8155f52b>] system_call_fastpath+0x16/0x1b BUG: unable to handle kernel NULL pointer dereference at 0000000000000650 IP: [<ffffffff81388e19>] scsi_prep_state_check+0x9/0x90 PGD 0 Oops: 0000 [#1] SMP CPU 2 Modules linked in: nls_utf8 udf ses enclosure netconsole configfs fuse sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ipv6 kvm_intel kvm uinput snd_hda_codec_hdmi snd_hda_codec_realtek snd_seq snd_seq_device snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_timer snd soundcore iTCO_wdt snd_page_alloc iTCO_vendor_support joydev i7core_edac edac_core broadcom tg3 e1000 dcdbas microcode serio_raw pcspkr i2c_i801 firewire_ohci firewire_core crc_itu_t usb_storage radeon ttm drm_kms_helper drm i2c_algo_bit i2c_core [last unloaded: scsi_wait_scan] Pid: 2527, comm: umount Not tainted 3.0.0-rc5+ #8 Dell Inc. Studio XPS 8000/0X231R RIP: 0010:[<ffffffff81388e19>] [<ffffffff81388e19>] scsi_prep_state_check+0x9/0x90 RSP: 0018:ffff88021b3859c8 EFLAGS: 00010086 RAX: ffffffff81389a70 RBX: ffff88022d2c85a0 RCX: 0000000000001fa7 RDX: 0000000000000001 RSI: ffff88022d2c85a0 RDI: 0000000000000000 RBP: ffff88021b3859c8 R08: 0000000000000004 R09: 0000000000000002 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88022e0a9428 R13: ffff88022d2c85a0 R14: 0000000000000000 R15: ffff88022e404d20 FS: 00007f2d10454760(0000) GS:ffff88023fc80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000650 CR3: 0000000214443000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process umount (pid: 2527, threadinfo ffff88021b384000, task ffff88022e02dc80) Stack: ffff88021b3859f8 ffffffff8138992b ffff88022d2c85a0 ffff88022e0a9428 ffff88022d2c85a0 ffff88021b385cf8 ffff88021b385a18 ffffffff81389abd ffff88022d2c85a0 ffff88022e0a9428 ffff88021b385a48 ffffffff812847ad Call Trace: [<ffffffff8138992b>] scsi_setup_blk_pc_cmnd+0x2b/0x170 [<ffffffff81389abd>] scsi_prep_fn+0x4d/0x60 [<ffffffff812847ad>] blk_peek_request+0xbd/0x230 [<ffffffff8138a1ea>] scsi_request_fn+0x44a/0x470 [<ffffffff8127e42b>] __blk_run_queue+0x1b/0x20 [<ffffffff812885a3>] blk_execute_rq_nowait+0x63/0xb0 [<ffffffff81288676>] blk_execute_rq+0x86/0xf0 [<ffffffff8128430d>] ? blk_get_request+0x6d/0xa0 [<ffffffff81389c6c>] scsi_execute+0xfc/0x160 [<ffffffff8138a40a>] scsi_execute_req+0xca/0x140 [<ffffffff81383ea8>] ioctl_internal_command.clone.4+0x68/0x1a0 [<ffffffff81103f82>] ? pagevec_lookup+0x22/0x30 [<ffffffff8138405e>] scsi_set_medium_removal+0x7e/0xb0 [<ffffffff813c4d63>] cdrom_release+0xa3/0x260 [<ffffffff8118157e>] ? invalidate_bh_lru+0x2e/0x50 [<ffffffff81181550>] ? buffer_cpu_notify+0xa0/0xa0 [<ffffffff8139a088>] sr_block_release+0x38/0x60 [<ffffffff8118833c>] __blkdev_put+0x16c/0x1b0 [<ffffffff811883b2>] blkdev_put+0x32/0x130 [<ffffffff8115650e>] kill_block_super+0x4e/0x80 [<ffffffff81156865>] deactivate_locked_super+0x45/0x70 [<ffffffff8115724a>] deactivate_super+0x4a/0x70 [<ffffffff81171d54>] mntput_no_expire+0xc4/0x110 [<ffffffff81172a2c>] sys_umount+0x6c/0x360 [<ffffffff8155f52b>] system_call_fastpath+0x16/0x1b Code: 7b 58 e8 4b ea 1c 00 48 8b 4d a8 48 89 45 b8 48 89 cf e8 7b 88 ff ff eb a1 66 0f 1f 84 00 00 00 00 00 55 48 89 e5 66 66 66 66 90 <8b> 87 50 06 00 00 83 f8 02 75 04 31 c0 c9 c3 83 e8 04 83 f8 04 RIP [<ffffffff81388e19>] scsi_prep_state_check+0x9/0x90 RSP <ffff88021b3859c8> CR2: 0000000000000650 ---[ end trace 06d5981e67b7b7c9 ]--- --- Which goes from the device unplug to the oops. However, there are puts missing from this; particularly the one where the reference goes to zero. James -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
