diff options
Diffstat (limited to 'results/classifier/gemma3:12b/kernel/1813045')
| -rw-r--r-- | results/classifier/gemma3:12b/kernel/1813045 | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/results/classifier/gemma3:12b/kernel/1813045 b/results/classifier/gemma3:12b/kernel/1813045 new file mode 100644 index 00000000..b265cdc5 --- /dev/null +++ b/results/classifier/gemma3:12b/kernel/1813045 @@ -0,0 +1,17 @@ + +qemu-ga fsfreeze crashes the kernel + +We use mainly Cloudlinux, Debian and Centos. +We experienced many crashes on our qemu instances based on Cloudlinux during a snapshot. +The issue is not related to CloudLinux directly, but to Qemu agent, which does not freeze the file system(s) correctly. What is actually happening: + +When VM backup is invoked, Qemu agent freezes the file systems, so no single change will be made during the backup. But Qemu agent does not respect the loop* devices in freezing order (we have checked its sources), which leads to the next situation: +1) freeze loopback fs + ---> send async reqs to loopback thread +2) freeze main fs +3) loopback thread wakes up and trying to write data to the main fs, which is still frozen, and this finally leads to the hung task and kernel crash. + +I believe this is the culprit: + +/dev/loop0 /tmp ext3 rw,nosuid,noexec,relatime,data=ordered 0 0 +/dev/loop0 /var/tmp ext3 rw,nosuid,noexec,relatime,data=ordered 0 0 \ No newline at end of file |