Add basic deadlock detection for container start/remove

We can easily tell if we're going to deadlock by comparing lock
IDs before actually taking the lock. Add a few checks for this in
common places where deadlocks might occur.

This does not yet cover pod operations, where detection is more
difficult (and costly) due to the number of locks being involved
being higher than 2.

Also, add some error wrapping on the Podman side, so we can tell
people to use `system renumber` when it occurs.

Signed-off-by: Matthew Heon <matthew.heon@pm.me>

1 files changed, 5 insertions, 0 deletions

diff --git a/libpod/define/errors.go b/libpod/define/errors.go
index 523062866..b79cf08dc 100644
--- a/libpod/define/errors.go
+++ b/libpod/define/errors.go
@@ -61,6 +61,11 @@ var (
 	// the user.
 	ErrDetach = utils.ErrDetach
 
+	// ErrWillDeadlock indicates that the requested operation will cause a
+	// deadlock. This is usually caused by upgrade issues, and is resolved
+	// by renumbering the locks.
+	ErrWillDeadlock = errors.New("deadlock due to lock mismatch")
+
 	// ErrNoCgroups indicates that the container does not have its own
 	// CGroup.
 	ErrNoCgroups = errors.New("this container does not have a cgroup")