6.12-stable review patch. If anyone has any objections, please let me know.
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From: Matthew Brost matthew.brost@intel.com
commit 391008f34e711253c5983b0bf52277cc43723127 upstream.
For an unknown reason the math to determine the PF queue size does is not correct - compute UMD applications are overflowing the PF queue which is fatal. A multippier of 8 fixes the problem.
Fixes: 3338e4f90c14 ("drm/xe: Use topology to determine page fault queue size") Cc: stable@vger.kernel.org Signed-off-by: Matthew Brost matthew.brost@intel.com Reviewed-by: Jagmeet Randhawa jagmeet.randhawa@intel.com Link: https://lore.kernel.org/r/20250408155915.78770-1-matthew.brost@intel.com (cherry picked from commit 29582e0ea75c95668d168b12406e3c56cf5a73c4) Signed-off-by: Lucas De Marchi lucas.demarchi@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/xe/xe_gt_pagefault.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
--- a/drivers/gpu/drm/xe/xe_gt_pagefault.c +++ b/drivers/gpu/drm/xe/xe_gt_pagefault.c @@ -423,9 +423,16 @@ static int xe_alloc_pf_queue(struct xe_g num_eus = bitmap_weight(gt->fuse_topo.eu_mask_per_dss, XE_MAX_EU_FUSE_BITS) * num_dss;
- /* user can issue separate page faults per EU and per CS */ + /* + * user can issue separate page faults per EU and per CS + * + * XXX: Multiplier required as compute UMD are getting PF queue errors + * without it. Follow on why this multiplier is required. + */ +#define PF_MULTIPLIER 8 pf_queue->num_dw = - (num_eus + XE_NUM_HW_ENGINES) * PF_MSG_LEN_DW; + (num_eus + XE_NUM_HW_ENGINES) * PF_MSG_LEN_DW * PF_MULTIPLIER; +#undef PF_MULTIPLIER
pf_queue->gt = gt; pf_queue->data = devm_kcalloc(xe->drm.dev, pf_queue->num_dw,