diff mbox series

[Bug,1923583,NEW] colo: pvm flush failed after svm killed

Message ID 161830261172.29345.7866671962411605196.malonedeb@wampee.canonical.com (mailing list archive)
State New, archived
Headers show
Series [Bug,1923583,NEW] colo: pvm flush failed after svm killed | expand

Commit Message

Thomas Huth April 13, 2021, 8:30 a.m. UTC
Public bug reported:

   Primary vm flush failed after killing svm, which leads primary vm guest filesystem unavailable.

qemu versoin: 5.2.0
host/guest os: CentOS Linux release 7.6.1810 (Core)

Reproduce steps:
1. create colo vm following https://github.com/qemu/qemu/blob/master/docs/COLO-FT.txt
2. kill secondary vm (don't remove nbd child from quorum on primary vm)and wait for a minute. the interval depends on guest os.
result: primary vm file system shutdown because of flush cache error.

After serveral tests, I found that qemu-5.0.0 worked well, and it's the
Flush all children in generic code) leads this change, and both virtio-
blk and ide turned out to be bad.

I think it's nbd(replication) flush failed leads bdrv_co_flush(quorum_bs) failed, here is the call stack.
#0  bdrv_co_flush (bs=0x56242b3cc0b0=nbd_bs) at ../block/io.c:2856
#1  0x0000562428b0f399 in bdrv_co_flush (bs=0x56242b3c7e00=replication_bs) at ../block/io.c:2920
#2  0x0000562428b0f399 in bdrv_co_flush (bs=0x56242a4ad800=quorum_bs) at ../block/io.c:2920
#3  0x0000562428b70d56 in blk_do_flush (blk=0x56242a4ad4a0) at ../block/block-backend.c:1672
#4  0x0000562428b70d87 in blk_aio_flush_entry (opaque=0x7fd0980073f0) at ../block/block-backend.c:1680
#5  0x0000562428c5f9a7 in coroutine_trampoline (i0=-1409269904, i1=32721) at ../util/coroutine-ucontext.c:173

While i am not sure whether i use colo inproperly? Can we assume that
nbd child of quorum immediately removed right after svm crashed? Or it's
really a bug? Does the following patch fix? Help is needed! Thanks a

** Affects: qemu
     Importance: Undecided
         Status: New

** Patch added: "primary guest kernel message"


no-reply@patchew.org April 13, 2021, 8:45 a.m. UTC | #1
Patchew URL: https://patchew.org/QEMU/161830261172.29345.7866671962411605196.malonedeb@wampee.canonical.com/


This series seems to have some coding style problems. See output below for
more information:

Type: series
Message-id: 161830261172.29345.7866671962411605196.malonedeb@wampee.canonical.com
Subject: [Bug 1923583] [NEW] colo: pvm flush failed after svm killed

git rev-parse base > /dev/null || exit 0
git config --local diff.renamelimit 0
git config --local diff.renames True
git config --local diff.algorithm histogram
./scripts/checkpatch.pl --mailback base..

Updating 3c8cf5a9c21ff8782164d1def7f44bd888713384
From https://github.com/patchew-project/qemu
 * [new tag]         patchew/161830261172.29345.7866671962411605196.malonedeb@wampee.canonical.com -> patchew/161830261172.29345.7866671962411605196.malonedeb@wampee.canonical.com
 - [tag update]      patchew/20210413081008.3409459-1-f4bug@amsat.org -> patchew/20210413081008.3409459-1-f4bug@amsat.org
Switched to a new branch 'test'
f43885d colo: pvm flush failed after svm killed

ERROR: Missing Signed-off-by: line(s)

total: 1 errors, 0 warnings, 8 lines checked

Commit f43885d3a7e9 (colo: pvm flush failed after svm killed) has style problems, please review.  If any of these errors
are false positives report them to the maintainer, see
=== OUTPUT END ===

Test command exited with code: 1

The full log is available at
Email generated automatically by Patchew [https://patchew.org/].
Please send your feedback to patchew-devel@redhat.com
Thomas Huth May 15, 2021, 10:23 a.m. UTC | #2
The QEMU project is currently moving its bug tracking to another system.
For this we need to know which bugs are still valid and which could be
closed already. Thus we are setting the bug state to "Incomplete" now.

If the bug has already been fixed in the latest upstream version of QEMU,
then please close this ticket as "Fix released".

If it is not fixed yet and you think that this bug report here is still
valid, then you have two options:

1) If you already have an account on gitlab.com, please open a new ticket
for this problem in our new tracker here:


and then close this ticket here on Launchpad (or let it expire auto-
matically after 60 days). Please mention the URL of this bug ticket on
Launchpad in the new ticket on GitLab.

2) If you don't have an account on gitlab.com and don't intend to get
one, but still would like to keep this ticket opened, then please switch
the state back to "New" or "Confirmed" within the next 60 days (other-
wise it will get closed as "Expired"). We will then eventually migrate
the ticket automatically to the new system (but you won't be the reporter
of the bug in the new system and thus you won't get notified on changes

Thank you and sorry for the inconvenience.

** Changed in: qemu
       Status: New => Incomplete
diff mbox series


diff --git a/block/quorum.c b/block/quorum.c
index cfc1436..f2c0805 100644
--- a/block/quorum.c
+++ b/block/quorum.c
@@ -1279,7 +1279,7 @@  static BlockDriver bdrv_quorum = {
     .bdrv_dirname                       = quorum_dirname,
     .bdrv_co_block_status               = quorum_co_block_status,
-    .bdrv_co_flush_to_disk              = quorum_co_flush,
+    .bdrv_co_flush                      = quorum_co_flush,
     .bdrv_getlength                     = quorum_getlength,