]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
drm/xe/guc: Add devm release action to safely tear down CT
authorSatyanarayana K V P <satyanarayana.k.v.p@intel.com>
Mon, 1 Sep 2025 07:25:41 +0000 (12:55 +0530)
committerMichal Wajdeczko <michal.wajdeczko@intel.com>
Tue, 2 Sep 2025 06:21:58 +0000 (08:21 +0200)
commitee4b32220a6b41e71512e8804585325e685456ba
treef5e5c060bf8759dbfef53ffa8865ce549a8f0c0d
parent1047bd82794a1eab64d643f196d09171ce983f44
drm/xe/guc: Add devm release action to safely tear down CT

When a buffer object (BO) is allocated with the XE_BO_FLAG_GGTT_INVALIDATE
flag, the driver initiates TLB invalidation requests via the CTB mechanism
while releasing the BO. However a premature release of the CTB BO can lead
to system crashes, as observed in:

Oops: Oops: 0000 [#1] SMP NOPTI
RIP: 0010:h2g_write+0x2f3/0x7c0 [xe]
Call Trace:
 guc_ct_send_locked+0x8b/0x670 [xe]
 xe_guc_ct_send_locked+0x19/0x60 [xe]
 send_tlb_invalidation+0xb4/0x460 [xe]
 xe_gt_tlb_invalidation_ggtt+0x15e/0x2e0 [xe]
 ggtt_invalidate_gt_tlb.part.0+0x16/0x90 [xe]
 ggtt_node_remove+0x110/0x140 [xe]
 xe_ggtt_node_remove+0x40/0xa0 [xe]
 xe_ggtt_remove_bo+0x87/0x250 [xe]

Introduce a devm-managed release action during xe_guc_ct_init() and
xe_guc_ct_init_post_hwconfig() to ensure proper CTB disablement before
resource deallocation, preventing the use-after-free scenario.

Signed-off-by: Satyanarayana K V P <satyanarayana.k.v.p@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Summers Stuart <stuart.summers@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://lore.kernel.org/r/20250901072541.31461-1-satyanarayana.k.v.p@intel.com
drivers/gpu/drm/xe/xe_guc.c
drivers/gpu/drm/xe/xe_guc_ct.c
drivers/gpu/drm/xe/xe_guc_ct.h