Bug 818371
Summary: | kernel crashes when snapshots of mounted raid volumes are taken | ||||||
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Product: | Red Hat Enterprise Linux 6 | Reporter: | Corey Marthaler <cmarthal> | ||||
Component: | kernel | Assignee: | Jonathan Earl Brassow <jbrassow> | ||||
Status: | CLOSED ERRATA | QA Contact: | Cluster QE <mspqa-list> | ||||
Severity: | urgent | Docs Contact: | |||||
Priority: | urgent | ||||||
Version: | 6.3 | CC: | agk, borgan, dwysocha, heinzm, jbrassow, mbroz, msnitzer, nperic, prajnoha, prockai, syeghiay, thornber, zkabelac | ||||
Target Milestone: | rc | ||||||
Target Release: | --- | ||||||
Hardware: | x86_64 | ||||||
OS: | Linux | ||||||
Whiteboard: | |||||||
Fixed In Version: | kernel-2.6.32-274.el6 | Doc Type: | Bug Fix | ||||
Doc Text: |
When creating a snapshot of a mounted RAID volume, a kernel panic could occur. This happened because a timer designed to wake up an I/O processing thread was not deactivated when the RAID device was replace by a snapshot origin. The timer then woke a thread that attempted to access memory that had already been freed, resulting in a kernel panic. With this update, this bug has been fixed and the kernel panic no longer occurs in this scenario.
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Story Points: | --- | ||||
Clone Of: | |||||||
: | 821454 (view as bug list) | Environment: | |||||
Last Closed: | 2012-06-20 14:00:23 UTC | Type: | Bug | ||||
Regression: | --- | Mount Type: | --- | ||||
Documentation: | --- | CRM: | |||||
Verified Versions: | Category: | --- | |||||
oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||
Cloudforms Team: | --- | Target Upstream Version: | |||||
Embargoed: | |||||||
Bug Depends On: | |||||||
Bug Blocks: | 821454 | ||||||
Attachments: |
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Description
Corey Marthaler
2012-05-02 21:33:24 UTC
(Moving to kernel component). Do you have a crashdump or serial console log of the crash? This happens even when the raid1 origin volume is fully in sync (in the original report it is not). Anything on the console is lost right away due to the not stop spewing of information: [...] Do you have a strange power saving mode enabled? Dazed and confused, but trying to continue Uhhuh. NMI received for unknown reason 21 on CPU 0. [...] May 2 17:00:29 taft-01 qarshd[2987]: Running cmdline: lvcreate -s /dev/snapper/origin -c 128 -n merge1 -L 2G May 2 17:00:30 taft-01 kernel: md/raid1:mdX: active with 2 out of 2 mirrors May 2 17:00:30 taft-01 kernel: created bitmap (4 pages) for device mdX May 2 17:00:30 taft-01 kernel: mdX: bitmap initialized from disk: read 1/1 pages, set 1 of 8192 bits May 2 17:00:30 taft-01 lvm[1241]: No longer monitoring RAID device snapper-origin for events. May 2 17:00:33 taft-01 lvm[1241]: Monitoring snapshot snapper-merge1 May 2 17:00:33 taft-01 lvm[1241]: Monitoring RAID device snapper-origin-real for events. [POWER CYCLE] May 2 17:07:06 taft-01 kernel: imklog 5.8.7, log source = /proc/kmsg started. May 2 17:07:06 taft-01 rsyslogd: [origin software="rsyslogd" swVersion="5.8.7" x-pid="1523" x-info="http://www.rsyslog.com"] start May 2 17:07:06 taft-01 kernel: Initializing cgroup subsys cpuset May 2 17:07:06 taft-01 kernel: Initializing cgroup subsys cpu May 2 17:07:06 taft-01 kernel: Linux version 2.6.32-269.el6.x86_64 (mockbuild.bos.redhat.com) (gcc version 4.4.6 20110731 (Red Hat 4.4.6-3) (GCC) ) #1 SMP Tue May 1 19:16:31 EDT 2012 May 2 17:07:06 taft-01 kernel: Command line: ro root=/dev/mapper/vg_taft01-lv_root rd_LVM_LV=vg_taft01/lv_swap LANG=en_US.UTF-8 rd_NO_MD KEYTABLE=us rd_NO_LUKS SYSFONT=latarcyrheb-sun16 crashkernel=auto console=ttyS0,115200n8 rd_LVM_LV=vg_taft01/lv_root rd_NO_DM May 2 17:07:06 taft-01 kernel: KERNEL supported cpus: May 2 17:07:06 taft-01 kernel: Intel GenuineIntel May 2 17:07:06 taft-01 kernel: AMD AuthenticAMD May 2 17:07:06 taft-01 kernel: Centaur CentaurHauls May 2 17:07:06 taft-01 kernel: BIOS-provided physical RAM map: May 2 17:07:06 taft-01 kernel: BIOS-e820: 0000000000000000 - 00000000000a0000 (usable) I hit the same issue with the first run of the test: ============================================================ Iteration 1 of 5 started at Thu May 3 09:40:30 CDT 2012 ============================================================ SCENARIO - [write_to_snap_merge] Create snaps of origin with fs data, verify data on snaps, change data on snaps, merge data back to origin, verify origin data Making origin volume ** creating RAID1 origin ** lvcreate --type raid1 -m 1 -L 4G snapper -n origin Waiting until all mirror|raid volumes become fully syncd... 0/1 mirror(s) are fully synced: ( 12.55% ) 0/1 mirror(s) are fully synced: ( 25.58% ) 0/1 mirror(s) are fully synced: ( 30.01% ) 0/1 mirror(s) are fully synced: ( 37.88% ) 0/1 mirror(s) are fully synced: ( 41.58% ) 0/1 mirror(s) are fully synced: ( 45.91% ) 0/1 mirror(s) are fully synced: ( 50.22% ) 0/1 mirror(s) are fully synced: ( 54.76% ) 0/1 mirror(s) are fully synced: ( 59.28% ) 0/1 mirror(s) are fully synced: ( 64.02% ) 0/1 mirror(s) are fully synced: ( 68.26% ) 0/1 mirror(s) are fully synced: ( 72.38% ) 0/1 mirror(s) are fully synced: ( 76.45% ) 0/1 mirror(s) are fully synced: ( 81.12% ) 0/1 mirror(s) are fully synced: ( 85.18% ) 0/1 mirror(s) are fully synced: ( 89.33% ) 0/1 mirror(s) are fully synced: ( 93.61% ) 0/1 mirror(s) are fully synced: ( 99.08% ) 1/1 mirror(s) are fully synced: ( 100.00% ) Placing an ext filesystem on origin volume mke2fs 1.41.12 (17-May-2010) Mounting origin volume Writing files to /mnt/origin checkit starting with: CREATE Num files: 500 Random Seed: 4019 Verify XIOR Stream: /tmp/original.22269 Working dir: /mnt/origin Checking files on /mnt/origin checkit starting with: VERIFY Verify XIOR Stream: /tmp/original.22269 Working dir: /mnt/origin Making 5 snapshots of the origin volume, mounting, and verifying original data lvcreate -s /dev/snapper/origin -c 128 -n merge1 -L 2G Could not connect to node01:5008, 110: Connection timed out +++ Mounting and verifying snapshot merge1 data +++ Could not connect to node01:5008, 110: Connection timed out Could not connect to node01:5008, 113: No route to host /var/log/messages is generally silent: May 3 09:43:59 node01 qarshd[4024]: Running cmdline: lvcreate -s /dev/snapper/origin -c 128 -n merge1 -L 2G May 3 09:44:00 node01 kernel: md/raid1:mdX: active with 2 out of 2 mirrors May 3 09:44:00 node01 kernel: created bitmap (4 pages) for device mdX May 3 09:44:00 node01 kernel: mdX: bitmap initialized from disk: read 1/1 pages, set 122 of 8192 bits May 3 09:44:00 node01 lvm[2614]: No longer monitoring RAID device snapper-origin for events. May 3 09:44:00 node01 lvm[2614]: Monitoring snapshot snapper-merge1 May 3 09:44:00 node01 lvm[2614]: Monitoring RAID device snapper-origin-real for events. *POOF* May 3 09:45:37 node01 kernel: imklog 5.8.10, log source = /proc/kmsg started. May 3 09:45:37 node01 rsyslogd: [origin software="rsyslogd" swVersion="5.8.10" x-pid="1306" x-info="http://www.rsyslog.com"] start Here is the output from crash dump: KERNEL: /usr/lib/debug/lib/modules/2.6.32-268.el6.x86_64/vmlinux DUMPFILE: vmcore [PARTIAL DUMP] CPUS: 1 DATE: Thu May 3 09:44:01 2012 UPTIME: 04:40:27 LOAD AVERAGE: 1.08, 0.60, 0.24 TASKS: 184 NODENAME: node01 RELEASE: 2.6.32-268.el6.x86_64 VERSION: #1 SMP Tue Apr 24 16:27:49 EDT 2012 MACHINE: x86_64 (2659 Mhz) MEMORY: 1 GB PANIC: "" PID: 4082 COMMAND: "lvm" TASK: ffff88003ba41540 [THREAD_INFO: ffff88003cc1a000] CPU: 0 STATE: TASK_RUNNING (PANIC) PID: 4082 TASK: ffff88003ba41540 CPU: 0 COMMAND: "lvm" #0 [ffff880002203be0] machine_kexec at ffffffff8103281b #1 [ffff880002203c40] crash_kexec at ffffffff810ba5a2 #2 [ffff880002203d10] oops_end at ffffffff81500b80 #3 [ffff880002203d40] die at ffffffff8100f26b #4 [ffff880002203d70] do_general_protection at ffffffff81500712 #5 [ffff880002203da0] general_protection at ffffffff814ffee5 [exception RIP: run_timer_softirq+404] RIP: ffffffff8107e804 RSP: ffff880002203e50 RFLAGS: 00010246 RAX: ffff880002203e90 RBX: ffffffff81ea6100 RCX: 0000000000000000 RDX: 0000000000000100 RSI: dead000000200200 RDI: 4d414e5f564c5f4d RBP: ffff880002203ed0 R8: ffff880037c472e8 R9: 0000000000000001 R10: 0000000000000010 R11: 0000000000000000 R12: ffff880037c472b0 R13: ffff880002203e90 R14: 4d414e5f564c5f4d R15: 440072657070616e ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0000 #6 [ffff880002203ed8] __do_softirq at ffffffff81073e31 #7 [ffff880002203f48] call_softirq at ffffffff8100c24c #8 [ffff880002203f60] do_softirq at ffffffff8100de85 #9 [ffff880002203f80] irq_exit at ffffffff81073c15 #10 [ffff880002203f90] smp_apic_timer_interrupt at ffffffff815054d0 #11 [ffff880002203fb0] apic_timer_interrupt at ffffffff8100bc13 --- <IRQ stack> --- #12 [ffff88003cc1bf58] apic_timer_interrupt at ffffffff8100bc13 RIP: 00007ff039b98880 RSP: 00007fff0f67e5f0 RFLAGS: 00000246 RAX: 0000000000002d60 RBX: 0000000000000050 RCX: 0000000000000000 RDX: 0000000001c001e0 RSI: 0000000000000000 RDI: 00007ff039eaee80 RBP: ffffffff8100bc0e R8: 00000000ffffffff R9: 0000000000000000 R10: 0000000000000000 R11: 000000000000000b R12: 0000000000000016 R13: 00007fff0f67ef58 R14: 0000000001beee80 R15: 00000000000008a0 ORIG_RAX: ffffffffffffff10 CS: 0033 SS: 002b and the log says: md: mdX: resync done. RAID1 conf printout: --- wd:2 rd:2 disk 0, wo:0, o:1, dev:dm-3 disk 1, wo:0, o:1, dev:dm-5 SELinux: initialized (dev dm-6, type ext2), uses xattr md/raid1:mdX: active with 2 out of 2 mirrors created bitmap (4 pages) for device mdX mdX: bitmap initialized from disk: read 1/1 pages, set 122 of 8192 bits general protection fault: 0000 [#1] SMP last sysfs file: /sys/devices/platform/host6/session5/target6:0:0/6:0:0:1/block/sda/dev CPU 0 Modules linked in: ext2 dm_snapshot dm_raid raid1 raid456 async_raid6_recov async_pq raid6_pq async_xor xor async_memcpy async_tx nfsd lockd nfs_acl auth_rpcgss exportfs autofs4 sunrpc sg sd_mod crc_t10dif be2iscsi iscsi_boot_sysfs bnx2i cnic uio cxgb4i cxgb4 cxgb3i libcxgbi cxgb3 mdio ib_iser rdma_cm ib_cm iw_cm ib_sa ib_mad ib_core ib_addr ipv6 iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi microcode virtio_balloon virtio_net i2c_piix4 i2c_core ext4 mbcache jbd2 virtio_blk virtio_pci virtio_ring virtio pata_acpi ata_generic ata_piix dm_mirror dm_region_hash dm_log dm_mod [last unloaded: speedstep_lib] Pid: 4082, comm: lvm Not tainted 2.6.32-268.el6.x86_64 #1 Red Hat KVM RIP: 0010:[<ffffffff8107e804>] [<ffffffff8107e804>] run_timer_softirq+0x194/0x340 RSP: 0000:ffff880002203e50 EFLAGS: 00010246 RAX: ffff880002203e90 RBX: ffffffff81ea6100 RCX: 0000000000000000 RDX: 0000000000000100 RSI: dead000000200200 RDI: 4d414e5f564c5f4d RBP: ffff880002203ed0 R08: ffff880037c472e8 R09: 0000000000000001 R10: 0000000000000010 R11: 0000000000000000 R12: ffff880037c472b0 R13: ffff880002203e90 R14: 4d414e5f564c5f4d R15: 440072657070616e FS: 00007ff03ab567a0(0000) GS:ffff880002200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7bcb5820a0 CR3: 000000003c0a7000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process lvm (pid: 4082, threadinfo ffff88003cc1a000, task ffff88003ba41540) Stack: 00000000000c0c90 ffffffff81ea7d20 ffffffff81ea7920 ffffffff81ea7520 <d> ffff88003cc1bfd8 ffff88003cc1bfd8 0000010081038779 ffffffff81ea7120 <d> ffff880002203e90 ffff880002203e90 ffffffff8102b40d 0000000000000101 Call Trace: <IRQ> [<ffffffff8102b40d>] ? lapic_next_event+0x1d/0x30 [<ffffffff81073e31>] __do_softirq+0xc1/0x1e0 [<ffffffff81096bc0>] ? hrtimer_interrupt+0x140/0x250 [<ffffffff8100c24c>] call_softirq+0x1c/0x30 [<ffffffff8100de85>] do_softirq+0x65/0xa0 [<ffffffff81073c15>] irq_exit+0x85/0x90 [<ffffffff815054d0>] smp_apic_timer_interrupt+0x70/0x9b [<ffffffff8100bc13>] apic_timer_interrupt+0x13/0x20 <EOI> Code: c7 03 00 00 00 00 fb 66 0f 1f 44 00 00 48 8b 55 a8 8b 0d 98 84 b4 00 8b 92 44 e0 ff ff 85 c9 89 55 b4 0f 85 48 01 00 00 4c 89 f7 <41> ff d7 8b 15 bb 84 b4 00 85 d2 0f 85 0b 01 00 00 48 8b 45 a0 RIP [<ffffffff8107e804>] run_timer_softirq+0x194/0x340 RSP <ffff880002203e50> This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release. Finally able to capture what was spewed to the console just before the reboot. May 7 17:13:52 taft-01 qarshd[3083]: Running cmdline: lvs --noheadings -o lv_a1 general protection fault: 0000 [#1] SMP last sysfs file: /sys/devices/virtual/block/dm-9/uevent CPU 0 Modules linked in: ext2 sunrpc p4_clockmod freq_table speedstep_lib ipv6 dm_sna] Pid: 3083, comm: qarshd Not tainted 2.6.32-269.el6.x86_64 #1 Dell Computer Corp1 RIP: 0010:[<ffffffff8107e804>] [<ffffffff8107e804>] run_timer_softirq+0x194/0x0 RSP: 0018:ffff880028203e50 EFLAGS: 00010246 RAX: ffff880028203e90 RBX: ffffffff81ea6100 RCX: 0000000000000000 RDX: 0000000000000100 RSI: dead000000200200 RDI: 67a99b330a493eb0 RBP: ffff880028203ed0 R08: ffff880218d952e8 R09: 0000000000000001 R10: 0000000000000010 R11: 0000000000000000 R12: ffff880218d952b0 R13: ffff880028203e90 R14: 67a99b330a493eb0 R15: ca60ff2f5e510a70 FS: 00007f52079d8700(0000) GS:ffff880028200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001164568 CR3: 0000000217c5f000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process qarshd (pid: 3083, threadinfo ffff8801f83d0000, task ffff880215d66080) Stack: ffffffff810a2110 ffffffff81ea7d20 ffffffff81ea7920 ffffffff81ea7520 <d> ffff8801f83d1fd8 ffff8801f83d1fd8 0000010081012bd9 ffffffff81ea7120 <d> ffff880028203e90 ffff880028203e90 ffffffff8102b40d 0000000000000141 Call Trace: <IRQ> [<ffffffff810a2110>] ? tick_sched_timer+0x0/0xc0 [<ffffffff8102b40d>] ? lapic_next_event+0x1d/0x30 [<ffffffff81073e31>] __do_softirq+0xc1/0x1e0 [<ffffffff81096bc0>] ? hrtimer_interrupt+0x140/0x250 [<ffffffff8100c24c>] call_softirq+0x1c/0x30 [Initializing cgroup subsys cpuset Initializing cgroup subsys cpu Linux version 2.6.32-269.el6.x86_64 (mockbuild.bos.redhat.com) (g2 Command line: ro root=/dev/mapper/vg_taft01-lv_root rd_LVM_LV=vg_taft01/lv_swapK KERNEL supported cpus: Intel GenuineIntel AMD AuthenticAMD Centaur CentaurHauls I've added print statements to CTR, DTR, SUSPEND, and RESUME operations. They print out the operation being performed and the memory position of the dm_target struct. The print-outs seem to indicate that the ordering of the suspend/resume operations is wrong: 1) Table1 CTR 2) Table1 RESUME 3) Table2 CTR 4) Table2 RESUME 5) Snap CTR 6) Table1 SUSPEND 7) Table2 SUSPEND 8) Table2 RESUME 9) Snap RESUME 10) Table1 DTR Table2 should probably not be resumed before Table1 is suspended. Actual output below. device-mapper: raid: RAID CTR - 0xffffc90014aa0040 device-mapper: raid: Superblocks created for new array md/raid1:mdX: not clean -- starting background reconstruction md/raid1:mdX: active with 2 out of 2 mirrors Choosing daemon_sleep default (5 sec) created bitmap (4 pages) for device mdX device-mapper: raid: RAID RESUME, 0xffffc90014aa0040 mdX: bitmap file is out of date, doing full recovery mdX: bitmap initialized from disk: read 1/1 pages, set 8192 of 8192 bits md: resync of RAID array mdX md: minimum _guaranteed_ speed: 1000 KB/sec/disk. md: using maximum available idle IO bandwidth (but not more than 200000 KB/sec) f. md: using 128k window, over a total of 4194304k. md: mdX: resync done. [device-mapper: raid: RAID CTR - 0xffffc9001506b040 md/raid1:mdX: active with 2 out of 2 mirrors created bitmap (4 pages) for device mdX device-mapper: raid: RAID RESUME, 0xffffc9001506b040 mdX: bitmap initialized from disk: read 1/1 pages, set 1 of 8192 bits device-mapper: snapshots: SNAP CTR device-mapper: raid: RAID PRESUSPEND, 0xffffc90014aa0040 device-mapper: raid: RAID POSTSUSPEND, 0xffffc90014aa0040 device-mapper: raid: RAID PRESUSPEND, 0xffffc9001506b040 device-mapper: raid: RAID POSTSUSPEND, 0xffffc9001506b040 device-mapper: raid: RAID RESUME, 0xffffc9001506b040 device-mapper: snapshots: SNAP PRERESUME device-mapper: snapshots: SNAP RESUME device-mapper: raid: RAID DTR, 0xffffc90014aa0040 ------------[ cut here ]------------ kernel BUG at kernel/timer.c:960! Created attachment 583023 [details]
output of 'lvcreate -s' command showing possible bad ordering of suspend/resume
Here is the state of the machine before the command was issued (and the command issued to get the output attached here).
[root@bp-01 ~]# lvcreate --type raid1 -m 1 -L 500M -n lv vg
Logical volume "lv" created
[root@bp-01 ~]# dmsetup table | grep vg-
vg-lv: 0 1024000 raid raid1 3 0 region_size 1024 2 253:3 253:4 253:5 253:6
vg-lv_rmeta_1: 0 8192 linear 8:33 2048
vg-lv_rmeta_0: 0 8192 linear 8:17 2048
vg-lv_rimage_1: 0 1024000 linear 8:33 10240
vg-lv_rimage_0: 0 1024000 linear 8:17 10240
[root@bp-01 ~]# lvcreate -s vg/lv -L 500M -n snap -vvvvv >& output.txt
[
Ordering problem apparently also reproducible using original mirror implementation. Two separate problems: 1. userspace sending invalid sequence of operations; - this needs fixing for 6.3 2. kernel crash when it receives the invalid sequence. - if it's easy to detect the situation and return an error, we should do that - but otherwise it doesn't matter as it makes no sense for userspace to issue that sequence of ioctls. Moved the LVM2 part of this problem to bug 821454. This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release. I found the problem that is causing the kernel panic. MD is setting a timer that occasionally kicks the personality's I/O processing thread. In this case, the timer can go off after the mddev structure has been removed. This causes a dereference to an area of memory that has been freed - kernel panic. To fix the issue, I've submitted a patch to linux-raid that adds del_timer_sync to remove the timer before mddev_suspend finishes. We don't want a timer going off after an mddev_suspend is called. This is especially true with device-mapper, since it can call the destructor function immediately following a suspend. This results in the removal (kfree) of the structures upon which the timer depends - resulting in a very ugly panic. Therefore, we add a del_timer_sync to mddev_suspend to prevent this. While this approach works, it seems that 'md_stop_writes' should handle this properly. It calls del_timer_sync already, but then allows writes to /finish/ after it is called. Finishing writes call md_write_end, which resets the timer. Why call del_timer_sync at all in 'md_stop_writes' then? Given this line of reasoning, it may be more appropriate to have 'md_stop_writes' wait for all I/O to complete and then call 'del_timer_sync'. Then we wouldn't have to remove the timer in 'mddev_suspend'. Upstream patch/thread is here: https://www.redhat.com/archives/dm-devel/2012-May/msg00122.html ... and Neil's request for Linus to pull the patch into 3.4 is here: https://lkml.org/lkml/2012/5/17/6 Patch(es) available on kernel-2.6.32-274.el6 Patch(es) available on kernel-2.6.32-274.el6 Patch(es) available on kernel-2.6.32-274.el6 These test cases no longer fail with the latest kernel/lvm rpms. 2.6.32-274.el6.x86_64 lvm2-2.02.95-10.el6 BUILT: Fri May 18 03:26:00 CDT 2012 lvm2-libs-2.02.95-10.el6 BUILT: Fri May 18 03:26:00 CDT 2012 lvm2-cluster-2.02.95-10.el6 BUILT: Fri May 18 03:26:00 CDT 2012 udev-147-2.41.el6 BUILT: Thu Mar 1 13:01:08 CST 2012 device-mapper-1.02.74-10.el6 BUILT: Fri May 18 03:26:00 CDT 2012 device-mapper-libs-1.02.74-10.el6 BUILT: Fri May 18 03:26:00 CDT 2012 device-mapper-event-1.02.74-10.el6 BUILT: Fri May 18 03:26:00 CDT 2012 device-mapper-event-libs-1.02.74-10.el6 BUILT: Fri May 18 03:26:00 CDT 2012 cmirror-2.02.95-10.el6 BUILT: Fri May 18 03:26:00 CDT 2012 Verified with lvm2-2.02.95-10.el6.x86_64 kernel-2.6.32-278.el6.x86_64 as well Technical note added. If any revisions are required, please edit the "Technical Notes" field accordingly. All revisions will be proofread by the Engineering Content Services team. New Contents: When creating a snapshot of a mounted RAID volume, a kernel panic could occur. This happened because a timer designed to wake up an I/O processing thread was not deactivated when the RAID device was replace by a snapshot origin. The timer then woke a thread that attempted to access memory that had already been freed, resulting in a kernel panic. With this update, this bug has been fixed and the kernel panic no longer occurs in this scenario. Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. http://rhn.redhat.com/errata/RHSA-2012-0862.html |