6.15-stable review patch. If anyone has any objections, please let me know.
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From: Michal Wajdeczko michal.wajdeczko@intel.com
[ Upstream commit af2b588abe006bd55ddd358c4c3b87523349c475 ]
While we are indirectly draining our dedicated workqueue ggtt->wq that we use to complete asynchronous removal of some GGTT nodes, this happends as part of the managed-drm unwinding (ggtt_fini_early), which could be later then manage-device unwinding, where we could already unmap our MMIO/GMS mapping (mmio_fini).
This was recently observed during unsuccessful VF initialization:
[ ] xe 0000:00:02.1: probe with driver xe failed with error -62 [ ] xe 0000:00:02.1: DEVRES REL ffff88811e747340 __xe_bo_unpin_map_no_vm (16 bytes) [ ] xe 0000:00:02.1: DEVRES REL ffff88811e747540 __xe_bo_unpin_map_no_vm (16 bytes) [ ] xe 0000:00:02.1: DEVRES REL ffff88811e747240 __xe_bo_unpin_map_no_vm (16 bytes) [ ] xe 0000:00:02.1: DEVRES REL ffff88811e747040 tiles_fini (16 bytes) [ ] xe 0000:00:02.1: DEVRES REL ffff88811e746840 mmio_fini (16 bytes) [ ] xe 0000:00:02.1: DEVRES REL ffff88811e747f40 xe_bo_pinned_fini (16 bytes) [ ] xe 0000:00:02.1: DEVRES REL ffff88811e746b40 devm_drm_dev_init_release (16 bytes) [ ] xe 0000:00:02.1: [drm:drm_managed_release] drmres release begin [ ] xe 0000:00:02.1: [drm:drm_managed_release] REL ffff88810ef81640 __fini_relay (8 bytes) [ ] xe 0000:00:02.1: [drm:drm_managed_release] REL ffff88810ef80d40 guc_ct_fini (8 bytes) [ ] xe 0000:00:02.1: [drm:drm_managed_release] REL ffff88810ef80040 __drmm_mutex_release (8 bytes) [ ] xe 0000:00:02.1: [drm:drm_managed_release] REL ffff88810ef80140 ggtt_fini_early (8 bytes)
and this was leading to:
[ ] BUG: unable to handle page fault for address: ffffc900058162a0 [ ] #PF: supervisor write access in kernel mode [ ] #PF: error_code(0x0002) - not-present page [ ] Oops: Oops: 0002 [#1] SMP NOPTI [ ] Tainted: [W]=WARN [ ] Workqueue: xe-ggtt-wq ggtt_node_remove_work_func [xe] [ ] RIP: 0010:xe_ggtt_set_pte+0x6d/0x350 [xe] [ ] Call Trace: [ ] <TASK> [ ] xe_ggtt_clear+0xb0/0x270 [xe] [ ] ggtt_node_remove+0xbb/0x120 [xe] [ ] ggtt_node_remove_work_func+0x30/0x50 [xe] [ ] process_one_work+0x22b/0x6f0 [ ] worker_thread+0x1e8/0x3d
Add managed-device action that will explicitly drain the workqueue with all pending node removals prior to releasing MMIO/GSM mapping.
Fixes: 919bb54e989c ("drm/xe: Fix missing runtime outer protection for ggtt_remove_node") Signed-off-by: Michal Wajdeczko michal.wajdeczko@intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: Lucas De Marchi lucas.demarchi@intel.com Reviewed-by: Rodrigo Vivi rodrigo.vivi@intel.com Link: https://lore.kernel.org/r/20250612220937.857-2-michal.wajdeczko@intel.com (cherry picked from commit 89d2835c3680ab1938e22ad81b1c9f8c686bd391) Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/xe/xe_ggtt.c | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/drivers/gpu/drm/xe/xe_ggtt.c b/drivers/gpu/drm/xe/xe_ggtt.c index 5fcb2b4c2c139..60bce5de52725 100644 --- a/drivers/gpu/drm/xe/xe_ggtt.c +++ b/drivers/gpu/drm/xe/xe_ggtt.c @@ -201,6 +201,13 @@ static const struct xe_ggtt_pt_ops xelpg_pt_wa_ops = { .ggtt_set_pte = xe_ggtt_set_pte_and_flush, };
+static void dev_fini_ggtt(void *arg) +{ + struct xe_ggtt *ggtt = arg; + + drain_workqueue(ggtt->wq); +} + /** * xe_ggtt_init_early - Early GGTT initialization * @ggtt: the &xe_ggtt to be initialized @@ -257,6 +264,10 @@ int xe_ggtt_init_early(struct xe_ggtt *ggtt) if (err) return err;
+ err = devm_add_action_or_reset(xe->drm.dev, dev_fini_ggtt, ggtt); + if (err) + return err; + if (IS_SRIOV_VF(xe)) { err = xe_gt_sriov_vf_prepare_ggtt(xe_tile_get_gt(ggtt->tile, 0)); if (err)