There are quite a lot of places in podman were we have some signal
handlers, most notably libpod/shutdown/handler.go.
However when we rexec we do not want any of that and just send all
signals we get down to the child obviously. So before we install our
signal handler we must first reset all others with signal.Reset().
Also while at it fix a problem were the joinUserAndMountNS() code path
would not forward signals at all. This code path is used when you have
running containers but the pause process was killed.
Fixes#16091
Given that signal handlers run in different goroutines parallel it would
explain why it flakes sometimes in CI. However to my understanding this
flake can only happen when the pause process is dead before we run the
podman command. So the question still is what kills the pause process?
Signed-off-by: Paul Holzinger <pholzing@redhat.com>
Currently --tmpdir changes the location of the pause.pid file. this
causes issues because the c code in pkg/rootless does not know about
that. I tried to fix this[1] by fixing the c code to not use the
shortcut. While this fix worked it will result in many pause processes
leaking in the integrration tests.
Commit ab88632 added this behavior but following the disccusion it was
never the intention that we end up having more than one pause process.
The issues that was trying to fix was caused by somthing else AFAICT,
the main problem seems to be that the pause.pid file parent directory
may not be created when we try to create the pid file so it failed with
ENOENT. This patch fixes it by creating this directory always and revert
the change to no longer depend on the tmpdir value.
With this commit we now always use XDG_RUNTIME_DIR/libpod/tmp/pause.pid
for all podman processes. This allows the c shortcut to work reliably
and should therefore improve perfomance over my other approach.
A system test is added to ensure we see the right behavior and that
podman system migrate actually stops the pause process. Thanks to Ed
Santiago for the improved test to make it work for both `catatonit` and
`podman pause`.
This should fix the issues with namespace missmatches that we can see in
CI as flakes.
[1] https://github.com/containers/podman/pull/18057Fixes#18057
Signed-off-by: Paul Holzinger <pholzing@redhat.com>
