From fddca67cc633b28a73bbb1bb272018f5a3a7ea74 Mon Sep 17 00:00:00 2001 From: Radostin Stoyanov Date: Sun, 11 May 2025 11:33:29 +0100 Subject: [PATCH] seize: fix pause devices for frozen containers The container checkpointing procedure in Kubernetes freezes running containers to create a consistent snapshot of both the runtime state and the rootfs of the container. However, when checkpointing a GPU container, the container must be unfrozen before invoking the cuda-checkpoint tool. This is achieved in prepare_freezer_for_interrupt_only_mode(), which needs to be called before the PAUSE_DEVICES hook. The patch introducing this functionality fixes this problem for containers with multiple processes. However, if the container has a single process, prepare_freezer_for_interrupt_only_mode() must be invoked immediately before the PAUSE_DEVICES hook. Fixes: #2514 Signed-off-by: Radostin Stoyanov --- criu/seize.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/criu/seize.c b/criu/seize.c index f56357ac7..23f192d46 100644 --- a/criu/seize.c +++ b/criu/seize.c @@ -1060,22 +1060,32 @@ int collect_pstree(void) */ alarm(opts.timeout); - ret = run_plugins(PAUSE_DEVICES, pid); - if (ret < 0 && ret != -ENOTSUP) { - goto err; - } - if (opts.freeze_cgroup && cgroup_version()) goto err; pr_debug("Detected cgroup V%d freezer\n", cgroup_v2 ? 2 : 1); if (opts.freeze_cgroup && !compel_interrupt_only_mode) { + ret = run_plugins(PAUSE_DEVICES, pid); + if (ret < 0 && ret != -ENOTSUP) { + goto err; + } + if (freeze_processes()) goto err; } else { if (opts.freeze_cgroup && prepare_freezer_for_interrupt_only_mode()) goto err; + + /* + * Call PAUSE_DEVICES after prepare_freezer_for_interrupt_only_mode() + * to be able to checkpoint containers in a frozen state. + */ + ret = run_plugins(PAUSE_DEVICES, pid); + if (ret < 0 && ret != -ENOTSUP) { + goto err; + } + if (compel_interrupt_task(pid)) { set_cr_errno(ESRCH); goto err; @@ -1136,4 +1146,4 @@ int checkpoint_devices(void) exit_code = 0; err: return exit_code; -} \ No newline at end of file +}