1 files changed, 41 insertions, 0 deletions

diff --git a/gitlab/issues/target_missing/host_missing/accel_missing/520.toml b/gitlab/issues/target_missing/host_missing/accel_missing/520.toml
new file mode 100644
index 00000000..e8259194
--- /dev/null
+++ b/gitlab/issues/target_missing/host_missing/accel_missing/520.toml
@@ -0,0 +1,41 @@
+id = 520
+title = "qemu-ga fsfreeze crashes the kernel"
+state = "opened"
+created_at = "2021-08-09T09:27:29.740Z"
+closed_at = "n/a"
+labels = ["Guest Agent"]
+url = "https://gitlab.com/qemu-project/qemu/-/issues/520"
+host-os = "Proxmox 6.4"
+host-arch = "x86_64"
+qemu-version = "QEMU emulator version 5.2.0 (pve-qemu-kvm_5.2.0)"
+guest-os = "CentOS 7"
+guest-arch = "x86_64"
+description = """Hello,
+
+Still required your attention, duplicate from:
+https://bugs.launchpad.net/bugs/1807073
+https://bugs.launchpad.net/bugs/1813045
+
+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.
+
+Moreover, a lot of Proxmox users are complaining about the issue as well:
+https://forum.proxmox.com/threads/error-vm-100-qmp-command-guest-fsfreeze-thaw-failed-got-timeout.68082/
+https://forum.proxmox.com/threads/problem-with-fsfreeze-freeze-and-qemu-guest-agent.65707/"""
+reproduce = """1. Manually start backup for the VM with qemu-agent enabled.
+2. The backup process stuck at "INFO: issuing guest-agent 'fs-freeze' command"
+3. The VM become unavailable, you can only unlock it and force reset."""
+additional = """/var/log/messages logs:  
+Aug  6 21:54:00 cpanel qemu-ga: info: guest-ping called  
+Aug  6 21:54:01 cpanel qemu-ga: info: guest-fsfreeze called  
+Aug  6 21:54:01 cpanel qemu-ga: info: executing fsfreeze hook with arg 'freeze'  
+
+
+after this the VM becomes completely unavailable."""