drm/amdkfd: Fix the case that vm range is hole at svm_migrate_copy_to_vram

When migration vm range is hole at cpu side(MIGRATE_PFN_MIGRATE set +
MIGRATE_PFN_VALID unset) driver still allocates device pages. There is no
dma map of src pages and migration. j is 0 and svm_migrate_copy_memory_gart()
will return an uninitialized r. That can trigger out_free_vram_pages to drop
all VRAM just set up.

Initialize r and only call the last svm_migrate_copy_memory_gart if j > 0.

Current code postponed the last page to the final copy. This patch flushes on
the last page when reach to the end of current drm_buddy_block; avoids another
svm_migrate_copy_memory_gart.

Cc: stable@vger.kernel.org
Signed-off-by: Xiaogang Chen <xiaogang.chen@amd.com>
Reviewed-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

0 files changed, 0 insertions, 0 deletions