6.17-stable review patch. If anyone has any objections, please let me know.
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From: Matthew Brost matthew.brost@intel.com
[ Upstream commit 7ac74613e5f2ef3450f44fd2127198662c2563a9 ]
An array of VM binds can potentially evict other buffer objects (BOs) within the same VM under certain conditions, which may lead to NULL pointer dereferences later in the bind pipeline. To prevent this, clear the allow_res_evict flag in the xe_bo_validate call.
v2: - Invert polarity of no_res_evict (Thomas) - Add comment in code explaining issue (Thomas)
Cc: stable@vger.kernel.org Reported-by: Paulo Zanoni paulo.r.zanoni@intel.com Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6268 Fixes: 774b5fa509a9 ("drm/xe: Avoid evicting object of the same vm in none fault mode") Fixes: 77f2ef3f16f5 ("drm/xe: Lock all gpuva ops during VM bind IOCTL") Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs") Signed-off-by: Matthew Brost matthew.brost@intel.com Tested-by: Paulo Zanoni paulo.r.zanoni@intel.com Reviewed-by: Thomas Hellström thomas.hellstrom@linux.intel.com Link: https://lore.kernel.org/r/20251009110618.3481870-1-matthew.brost@intel.com (cherry picked from commit 8b9ba8d6d95fe75fed6b0480bb03da4b321bea08) Signed-off-by: Lucas De Marchi lucas.demarchi@intel.com [ removed exec parameter from xe_bo_validate() calls ] Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/xe/xe_vm.c | 32 +++++++++++++++++++++++--------- drivers/gpu/drm/xe/xe_vm_types.h | 2 ++ 2 files changed, 25 insertions(+), 9 deletions(-)
--- a/drivers/gpu/drm/xe/xe_vm.c +++ b/drivers/gpu/drm/xe/xe_vm.c @@ -2894,7 +2894,7 @@ static void vm_bind_ioctl_ops_unwind(str }
static int vma_lock_and_validate(struct drm_exec *exec, struct xe_vma *vma, - bool validate) + bool res_evict, bool validate) { struct xe_bo *bo = xe_vma_bo(vma); struct xe_vm *vm = xe_vma_vm(vma); @@ -2905,7 +2905,8 @@ static int vma_lock_and_validate(struct err = drm_exec_lock_obj(exec, &bo->ttm.base); if (!err && validate) err = xe_bo_validate(bo, vm, - !xe_vm_in_preempt_fence_mode(vm)); + !xe_vm_in_preempt_fence_mode(vm) && + res_evict); }
return err; @@ -2978,14 +2979,23 @@ static int prefetch_ranges(struct xe_vm }
static int op_lock_and_prep(struct drm_exec *exec, struct xe_vm *vm, - struct xe_vma_op *op) + struct xe_vma_ops *vops, struct xe_vma_op *op) { int err = 0; + bool res_evict; + + /* + * We only allow evicting a BO within the VM if it is not part of an + * array of binds, as an array of binds can evict another BO within the + * bind. + */ + res_evict = !(vops->flags & XE_VMA_OPS_ARRAY_OF_BINDS);
switch (op->base.op) { case DRM_GPUVA_OP_MAP: if (!op->map.invalidate_on_bind) err = vma_lock_and_validate(exec, op->map.vma, + res_evict, !xe_vm_in_fault_mode(vm) || op->map.immediate); break; @@ -2996,11 +3006,13 @@ static int op_lock_and_prep(struct drm_e
err = vma_lock_and_validate(exec, gpuva_to_vma(op->base.remap.unmap->va), - false); + res_evict, false); if (!err && op->remap.prev) - err = vma_lock_and_validate(exec, op->remap.prev, true); + err = vma_lock_and_validate(exec, op->remap.prev, + res_evict, true); if (!err && op->remap.next) - err = vma_lock_and_validate(exec, op->remap.next, true); + err = vma_lock_and_validate(exec, op->remap.next, + res_evict, true); break; case DRM_GPUVA_OP_UNMAP: err = check_ufence(gpuva_to_vma(op->base.unmap.va)); @@ -3009,7 +3021,7 @@ static int op_lock_and_prep(struct drm_e
err = vma_lock_and_validate(exec, gpuva_to_vma(op->base.unmap.va), - false); + res_evict, false); break; case DRM_GPUVA_OP_PREFETCH: { @@ -3025,7 +3037,7 @@ static int op_lock_and_prep(struct drm_e
err = vma_lock_and_validate(exec, gpuva_to_vma(op->base.prefetch.va), - false); + res_evict, false); if (!err && !xe_vma_has_no_bo(vma)) err = xe_bo_migrate(xe_vma_bo(vma), region_to_mem_type[region]); @@ -3069,7 +3081,7 @@ static int vm_bind_ioctl_ops_lock_and_pr return err;
list_for_each_entry(op, &vops->list, link) { - err = op_lock_and_prep(exec, vm, op); + err = op_lock_and_prep(exec, vm, vops, op); if (err) return err; } @@ -3698,6 +3710,8 @@ int xe_vm_bind_ioctl(struct drm_device * }
xe_vma_ops_init(&vops, vm, q, syncs, num_syncs); + if (args->num_binds > 1) + vops.flags |= XE_VMA_OPS_ARRAY_OF_BINDS; for (i = 0; i < args->num_binds; ++i) { u64 range = bind_ops[i].range; u64 addr = bind_ops[i].addr; --- a/drivers/gpu/drm/xe/xe_vm_types.h +++ b/drivers/gpu/drm/xe/xe_vm_types.h @@ -467,6 +467,8 @@ struct xe_vma_ops { struct xe_vm_pgtable_update_ops pt_update_ops[XE_MAX_TILES_PER_DEVICE]; /** @flag: signify the properties within xe_vma_ops*/ #define XE_VMA_OPS_FLAG_HAS_SVM_PREFETCH BIT(0) +#define XE_VMA_OPS_FLAG_MADVISE BIT(1) +#define XE_VMA_OPS_ARRAY_OF_BINDS BIT(2) u32 flags; #ifdef TEST_VM_OPS_ERROR /** @inject_error: inject error to test error handling */