[PATCH 5.19 619/717] drm/amdgpu: SDMA update use unlocked iterator

From: Greg Kroah-Hartman
Date: Sat Oct 22 2022 - 05:03:27 EST


From: Philip Yang <Philip.Yang@xxxxxxx>

[ Upstream commit 3913f0179ba366f7d7d160c506ce00de1602bbc4 ]

SDMA update page table may be called from unlocked context, this
generate below warning. Use unlocked iterator to handle this case.

WARNING: CPU: 0 PID: 1475 at
drivers/dma-buf/dma-resv.c:483 dma_resv_iter_next
Call Trace:
dma_resv_iter_first+0x43/0xa0
amdgpu_vm_sdma_update+0x69/0x2d0 [amdgpu]
amdgpu_vm_ptes_update+0x29c/0x870 [amdgpu]
amdgpu_vm_update_range+0x2f6/0x6c0 [amdgpu]
svm_range_unmap_from_gpus+0x115/0x300 [amdgpu]
svm_range_cpu_invalidate_pagetables+0x510/0x5e0 [amdgpu]
__mmu_notifier_invalidate_range_start+0x1d3/0x230
unmap_vmas+0x140/0x150
unmap_region+0xa8/0x110

Signed-off-by: Philip Yang <Philip.Yang@xxxxxxx>
Suggested-by: Felix Kuehling <felix.kuehling@xxxxxxx>
Reviewed-by: Christian König <christian.koenig@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_vm_sdma.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_sdma.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_sdma.c
index 1fd3cbca20a2..718db7d98e5a 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_sdma.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_sdma.c
@@ -211,12 +211,15 @@ static int amdgpu_vm_sdma_update(struct amdgpu_vm_update_params *p,
int r;

/* Wait for PD/PT moves to be completed */
- dma_resv_for_each_fence(&cursor, bo->tbo.base.resv,
- DMA_RESV_USAGE_KERNEL, fence) {
+ dma_resv_iter_begin(&cursor, bo->tbo.base.resv, DMA_RESV_USAGE_KERNEL);
+ dma_resv_for_each_fence_unlocked(&cursor, fence) {
r = amdgpu_sync_fence(&p->job->sync, fence);
- if (r)
+ if (r) {
+ dma_resv_iter_end(&cursor);
return r;
+ }
}
+ dma_resv_iter_end(&cursor);

do {
ndw = p->num_dw_left;
--
2.35.1