Another note: this can also be triggered only with rename operations on zvols:
$ sudo zfs create -V 4096k pool1/zfsrename 1 $ sudo zfs create -V 4096k pool1/zfsrename 3 and then in two shells in parallel: $ while : ; do echo "RENAME" `date`; sudo zfs rename pool1/testrename3 pool1/testrename4; sudo zfs rename pool1/testrename4 pool1/testrename3; done $ while : ; do echo "RENAME" `date`; sudo zfs rename pool1/testrename1 pool1/testrename2; sudo zfs rename pool1/testrename2 pool1/testrename1; done takes a bit longer than with the create rename destroy script from above, but triggers after 10-15 seconds in the same test VM: user@test:~$ sudo cat /proc/6338/stack [<ffffffffc02abc41>] spa_open_common+0x61/0x480 [zfs] [<ffffffffc02ac083>] spa_open+0x13/0x20 [zfs] [<ffffffffc02e2112>] pool_status_check.part.24+0x32/0xa0 [zfs] [<ffffffffc02e2509>] zfsdev_ioctl+0x389/0x4b0 [zfs] [<ffffffff8121e7df>] do_vfs_ioctl+0x29f/0x490 [<ffffffff8121ea49>] SyS_ioctl+0x79/0x90 [<ffffffff81821ff2>] entry_SYSCALL_64_fastpath+0x16/0x71 [<ffffffffffffffff>] 0xffffffffffffffff user@test:~$ sudo cat /proc/6333/stack [<ffffffffc01adc49>] cv_wait_common+0x109/0x140 [spl] [<ffffffffc01adc95>] __cv_wait+0x15/0x20 [spl] [<ffffffffc02ba225>] txg_wait_synced+0xe5/0x130 [zfs] [<ffffffffc0295ca9>] dsl_sync_task+0x179/0x260 [zfs] [<ffffffffc028b53b>] dsl_dir_rename+0x5b/0x80 [zfs] [<ffffffffc02de13d>] zfs_ioc_rename+0x10d/0x120 [zfs] [<ffffffffc02e25a3>] zfsdev_ioctl+0x423/0x4b0 [zfs] [<ffffffff8121e7df>] do_vfs_ioctl+0x29f/0x490 [<ffffffff8121ea49>] SyS_ioctl+0x79/0x90 [<ffffffff81821ff2>] entry_SYSCALL_64_fastpath+0x16/0x71 [<ffffffffffffffff>] 0xffffffffffffffff ** Attachment added: "ps faxl output" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1560869/+attachment/4608435/+files/psfaxl.log -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1560869 Title: Concurrent zfs create and rename operations can lock a zpool completely Status in linux package in Ubuntu: Incomplete Status in zfs-linux package in Ubuntu: New Bug description: When doing "zfs create -V" and "zfs rename" operations on the same zpool in parallel, there is a high chance for a deadlock leading to a complete hang of the zpool in question (i.e., all further zfs operations hang indefinitely). Attached you find a simple perl script that should trigger the bug (the pool variable needs to be set to your pool name), if run in two shells at the same time: $ for i in `seq 1 100`; do sudo ./zfsrenamebug.pl "A$i"; done $ for i in `seq 1 100`; do sudo ./zfsrenamebug.pl "B$i"; done Reported upstream in https://github.com/zfsonlinux/zfs/issues/4404 and apparently fixed with the linked commits. --- ApportVersion: 2.20-0ubuntu3 Architecture: amd64 AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: CurrentDesktop: Unity DistroRelease: Ubuntu 16.04 HibernationDevice: RESUME=UUID=41b79831-ff2c-4d62-8d09-0fd00a3fafad InstallationDate: Installed on 2016-03-18 (4 days ago) InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Alpha amd64 (20160307) IwConfig: ens18 no wireless extensions. lo no wireless extensions. Lsusb: Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub MachineType: QEMU Standard PC (i440FX + PIIX, 1996) NonfreeKernelModules: zfs zunicode zcommon znvpair zavl Package: zfs-linux ProcFB: 0 qxldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-15-generic root=UUID=ff5bf1a3-8ced-46a8-9e2e-e3e7d0e522c0 ro quiet splash vt.handoff=7 ProcVersionSignature: Ubuntu 4.4.0-15.31-generic 4.4.6 RelatedPackageVersions: linux-restricted-modules-4.4.0-15-generic N/A linux-backports-modules-4.4.0-15-generic N/A linux-firmware 1.157 RfKill: Tags: xenial Uname: Linux 4.4.0-15-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo _MarkForUpload: True dmi.bios.date: 04/01/2014 dmi.bios.vendor: SeaBIOS dmi.bios.version: rel-1.8.2-0-g33fbe13 by qemu-project.org dmi.chassis.type: 1 dmi.chassis.vendor: QEMU dmi.chassis.version: pc-i440fx-2.5 dmi.modalias: dmi:bvnSeaBIOS:bvrrel-1.8.2-0-g33fbe13byqemu-project.org:bd04/01/2014:svnQEMU:pnStandardPC(i440FX+PIIX,1996):pvrpc-i440fx-2.5:cvnQEMU:ct1:cvrpc-i440fx-2.5: dmi.product.name: Standard PC (i440FX + PIIX, 1996) dmi.product.version: pc-i440fx-2.5 dmi.sys.vendor: QEMU To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1560869/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
