Latest findings:
* The deepest loop that actually never exits is actually the `while not 
os.path.exists(fexit):` in the `eofcat` script. This is because the `block = 
os.read(0, 1000000)` always reads nothing.
* From the guest:
  * `head`ing the `stdin` file doesn't help.
  * `tail`ing the `stdin` file does help, it unblocks the loop, just the same 
way as `stat`ing it.
* From the host:
  * `stat`ing `stdin` doesn't change anything.
  * Appending more data to it doesn't change anything either.
  * This adds up with the fact that it's a kernel change in the guest that 
triggered the bug.
* That `stdin` file is stored on a 9p shared FS. This might be a related 
change, but nothing confirmed yet: 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c9b93cafb69cbbbe375de29c1ebf410dbc33ebfc

-- 
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/2056461

Title:
  autopkgtest-virt-qemu on noble images sometimes hangs doing copydown

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/autopkgtest/+bug/2056461/+subscriptions


-- 
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs

Reply via email to