On Mon, Oct 15, 2012 at 4:28 AM, Jonathan Nieder <jrnie...@gmail.com> wrote: > Hi, > > mail user wrote: > >> plugging in a fake (128 that later turned out to be just 2Gb) flashdrive >> in the usb port, dd it to /dev/null, ctrl-c, dd zeroes to it, ctrl-c, >> dd unresponsive to ctrl-c > > Thanks for a clear report. That sounds like a serious bug. Is it > reproducible?
Thanks for the fast reply. Yes, it is reproductible > > If so, full "dmesg" output after reproducing it and running > > echo w >/proc/sysrq-trigger > > would be very interesting. pasted here: http://paste.debian.net/200555/ Ben: no forced rmmod this time. exact steps performed: root@homerouter:~# dd if=/dev/zero bs=32M|tr '\000' '\377'|pv -br|dd of=/dev/sdb bs=32M ^C19+0 records in 18+0 records out 603979776 bytes (604 MB) copied, 17.3839 s, 34.7 MB/s --- Mon Oct 15 04:43:38 2012 8117 tail -f /var/log/all Mon Oct 15 04:46:31 2012 8171 [flush-8:16] Mon Oct 15 04:47:22 2012 8219 udevd --daemon Mon Oct 15 04:47:22 2012 8220 udevd --daemon Mon Oct 15 04:50:48 2012 8261 [kworker/1:1] Mon Oct 15 04:52:08 2012 8290 dd of=/dev/sdb bs=32M Mon Oct 15 04:52:25 2012 8293 /sbin/blkid -o udev -p /dev/sdb <- this launched at the time I pressed ctrl-c Mon Oct 15 04:52:59 2012 8297 ps -eo lstart,pid,cmd --- then udevd started complaining (lots of) Oct 15 04:53:27 homerouter udevd[8219]: timeout: killing '/sbin/blkid -o udev -p /dev/sdb' [8293] then later: Oct 15 04:57:49 homerouter kernel: [ 7080.616052] INFO: task blkid:8293 blockedfor more than 120 seconds. Oct 15 04:57:49 homerouter kernel: [ 7080.616100] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Oct 15 04:57:49 homerouter kernel: [ 7080.616163] blkid D ffff88011bc93740 0 8293 1 0x00000004 Oct 15 04:57:49 homerouter kernel: [ 7080.616243] ffff88011408a040 0000000000000086 0000000000000000 ffff880116f080c0 Oct 15 04:57:49 homerouter kernel: [ 7080.616369] 0000000000013740 ffff880109739fd8 ffff880109739fd8 ffff88011408a040 Oct 15 04:57:49 homerouter kernel: [ 7080.616496] 0000000000000100 0000000109739b60 ffff880109739b60 ffff88011214f3d8 Oct 15 04:57:49 homerouter kernel: [ 7080.616622] Call Trace: Oct 15 04:57:49 homerouter kernel: [ 7080.616662] [<ffffffff8134a2cf>] ? __mutex_lock_common.isra.5+0xff/0x164 Oct 15 04:57:49 homerouter kernel: [ 7080.616706] [<ffffffff8134a1bd>] ? mutex_lock+0x1a/0x2d Oct 15 04:57:49 homerouter kernel: [ 7080.616748] [<ffffffff81121565>] ? __blkdev_get+0x9a/0x3a9 Oct 15 04:57:49 homerouter kernel: [ 7080.616806] [<ffffffff81121b1b>] ? blkdev_get+0x2a7/0x2a7 Oct 15 04:57:49 homerouter kernel: [ 7080.616848] [<ffffffff81121a3b>] ? blkdev_get+0x1c7/0x2a7 Oct 15 04:57:49 homerouter kernel: [ 7080.616889] [<ffffffff81036457>] ? should_resched+0x5/0x23 Oct 15 04:57:49 homerouter kernel: [ 7080.616931] [<ffffffff81121b1b>] ? blkdev_get+0x2a7/0x2a7 Oct 15 04:57:49 homerouter kernel: [ 7080.616973] [<ffffffff810f7c66>] ? __dentry_open+0x19c/0x2b3 Oct 15 04:57:49 homerouter kernel: [ 7080.617015] [<ffffffff811010c8>] ? dget+0x12/0x1e Oct 15 04:57:49 homerouter kernel: [ 7080.617055] [<ffffffff81104239>] ? do_last+0x553/0x58d Oct 15 04:57:49 homerouter kernel: [ 7080.617095] [<ffffffff8110486b>] ? path_openat+0xce/0x32a Oct 15 04:57:49 homerouter kernel: [ 7080.617137] [<ffffffff810cd779>] ? pte_offset_kernel+0x16/0x35 Oct 15 04:57:49 homerouter kernel: [ 7080.617179] [<ffffffff81104b89>] ? do_filp_open+0x2a/0x6e Oct 15 04:57:49 homerouter kernel: [ 7080.617220] [<ffffffff813499cf>] ? _cond_resched+0x7/0x1c Oct 15 04:57:49 homerouter kernel: [ 7080.617263] [<ffffffff811b29d9>] ? __strncpy_from_user+0x18/0x48 Oct 15 04:57:49 homerouter kernel: [ 7080.617306] [<ffffffff8110d8bf>] ? alloc_fd+0x64/0x109 Oct 15 04:57:49 homerouter kernel: [ 7080.617346] [<ffffffff810f8b3b>] ? do_sys_open+0x5e/0xe5 Oct 15 04:57:49 homerouter kernel: [ 7080.617388] [<ffffffff8134fc92>] ? system_call_fastpath+0x16/0x1b > > [...] >> then >> rmmod -f usb-storage >> >> then >> unplug the flashdrive >> >> * What was the outcome of this action? >> >> forced removal of usb-storage produced the following kernel dmesg >> (ignore the tainted message, it is from the zfs/spl modules): >> >> Oct 15 00:40:50 homerouter kernel: [88756.711046] Disabling lock debugging >> due to kernel taint >> Oct 15 00:40:50 homerouter kernel: [88756.711092] usbcore: deregistering >> interface driver usb-storage >> Oct 15 00:40:51 homerouter kernel: [88757.349748] BUG: unable to handle >> kernel paging request at ffffffffa05b9020 >> Oct 15 00:40:51 homerouter kernel: [88757.349831] IP: [<ffffffffa018ef60>] >> scsi_device_put+0x11/0x3c [scsi_mod] > > Yeah, this part doesn't surprise me. Forced unloading of a module > doesn't generally work very well --- it's a hack to cope with some bad > situations, but generally the best policy is to reboot ASAP > afterwards. > > Hope that helps, > Jonathan -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
