6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jesse Zhang [ Upstream commit 8f3ecda0ab42fb5ba7310fe848013d3eff31b416 ] criu_process_info() evicts the queues of the process on every call, and each kfd_process_evict_queues() increments qpd->evicted, but CRIU UNPAUSE restores them only once. After PROCESS_INFO twice and UNPAUSE the queues stay evicted for good. On navi31, a barrier-AND packet on an HSA queue completes after PROCESS_INFO + UNPAUSE, but times out after PROCESS_INFO, PROCESS_INFO, UNPAUSE. The error path has a related problem: when kfd_process_evict_queues() itself fails, it has already rolled back its partial eviction, and the kfd_process_restore_queues() in the error path restores once more. Evict only when the queues are not paused yet, and on errors only undo an eviction done by this call. The barrier now completes after any number of PROCESS_INFO calls followed by UNPAUSE. Fixes: cd9f79103003 ("drm/amdkfd: CRIU Implement KFD unpause operation") Reviewed-by: Felix Kuehling Signed-off-by: Jesse Zhang Signed-off-by: Alex Deucher (cherry picked from commit 4d79c9e3c32c677fcadf5ca10ab81ee0a4b81f99) Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin --- drivers/gpu/drm/amd/amdkfd/kfd_chardev.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c index b90bfbd121f88..e4a6100d036ae 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c @@ -2703,6 +2703,7 @@ static int criu_process_info(struct file *filep, struct kfd_process *p, struct kfd_ioctl_criu_args *args) { + bool paused_here = false; int ret = 0; mutex_lock(&p->mutex); @@ -2713,11 +2714,15 @@ static int criu_process_info(struct file *filep, goto err_unlock; } - ret = kfd_process_evict_queues(p, KFD_QUEUE_EVICTION_CRIU_CHECKPOINT); - if (ret) - goto err_unlock; + /* UNPAUSE restores the queues once, so evict them only once */ + if (!p->queues_paused) { + ret = kfd_process_evict_queues(p, KFD_QUEUE_EVICTION_CRIU_CHECKPOINT); + if (ret) + goto err_unlock; - p->queues_paused = true; + p->queues_paused = true; + paused_here = true; + } args->pid = task_pid_nr_ns(p->lead_thread, task_active_pid_ns(p->lead_thread)); @@ -2732,7 +2737,7 @@ static int criu_process_info(struct file *filep, args->priv_data_size); err_unlock: - if (ret) { + if (ret && paused_here) { kfd_process_restore_queues(p); p->queues_paused = false; } -- 2.53.0