From 7090d7fc969fcc9985d7e538cfcd8a69a5f9c616 Mon Sep 17 00:00:00 2001 From: Matthew Brost Date: Wed, 24 Jul 2024 08:28:31 -0700 Subject: [PATCH] drm/xe: Move VM dma-resv lock from xe_exec_queue_create to __xe_exec_queue_init The critical section which requires the VM dma-resv is the call xe_lrc_create in __xe_exec_queue_init. Move this lock to __xe_exec_queue_init holding it just around xe_lrc_create. Not only is good practice, this also fixes a locking double of the VM dma-resv in the error paths of __xe_exec_queue_init as xe_lrc_put tries to acquire this too resulting in a deadlock. Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs") Cc: Maarten Lankhorst Signed-off-by: Matthew Brost Reviewed-by: Maarten Lankhorst Link: https://patchwork.freedesktop.org/patch/msgid/20240724152831.1848325-1-matthew.brost@intel.com (cherry picked from commit 549dd786b61cd3db903f5d94d07fc5a89ccdbeb9) Signed-off-by: Rodrigo Vivi --- drivers/gpu/drm/xe/xe_exec_queue.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/xe/xe_exec_queue.c b/drivers/gpu/drm/xe/xe_exec_queue.c index a39384bb9553..16f24f4a7062 100644 --- a/drivers/gpu/drm/xe/xe_exec_queue.c +++ b/drivers/gpu/drm/xe/xe_exec_queue.c @@ -105,22 +105,35 @@ static struct xe_exec_queue *__xe_exec_queue_alloc(struct xe_device *xe, static int __xe_exec_queue_init(struct xe_exec_queue *q) { + struct xe_vm *vm = q->vm; int i, err; + if (vm) { + err = xe_vm_lock(vm, true); + if (err) + return err; + } + for (i = 0; i < q->width; ++i) { q->lrc[i] = xe_lrc_create(q->hwe, q->vm, SZ_16K); if (IS_ERR(q->lrc[i])) { err = PTR_ERR(q->lrc[i]); - goto err_lrc; + goto err_unlock; } } + if (vm) + xe_vm_unlock(vm); + err = q->ops->init(q); if (err) goto err_lrc; return 0; +err_unlock: + if (vm) + xe_vm_unlock(vm); err_lrc: for (i = i - 1; i >= 0; --i) xe_lrc_put(q->lrc[i]); @@ -140,15 +153,7 @@ struct xe_exec_queue *xe_exec_queue_create(struct xe_device *xe, struct xe_vm *v if (IS_ERR(q)) return q; - if (vm) { - err = xe_vm_lock(vm, true); - if (err) - goto err_post_alloc; - } - err = __xe_exec_queue_init(q); - if (vm) - xe_vm_unlock(vm); if (err) goto err_post_alloc; -- 2.25.1