iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

drm/amdkfd: Fix UBSAN shift-out-of-bounds warning

Browse Source 
If get_num_sdma_queues or get_num_xgmi_sdma_queues is 0, we end up
doing a shift operation where the number of bits shifted equals
number of bits in the operand. This behaviour is undefined.

Set num_sdma_queues or num_xgmi_sdma_queues to ULLONG_MAX, if the
count is >= number of bits in the operand.

Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1472

Reported-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Anson Jacob <Anson.Jacob@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Tested-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Anson Jacob 2021-03-03 12:33:15 -05:00 committed by Alex Deucher
parent 47bfa5f60f
commit 50e2fc36e7
1 changed files with 15 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
View File

@ -1128,6 +1128,9 @@ static int set_sched_resources(struct device_queue_manager *dqm)
static int initialize_cpsch(struct device_queue_manager *dqm)
{
uint64_t num_sdma_queues;
uint64_t num_xgmi_sdma_queues;
pr_debug("num of pipes: %d\n", get_pipes_per_mec(dqm));
mutex_init(&dqm->lock_hidden);
@ -1136,8 +1139,18 @@ static int initialize_cpsch(struct device_queue_manager *dqm)
dqm->active_cp_queue_count = 0;
dqm->gws_queue_count = 0;
dqm->active_runlist = false;
dqm->sdma_bitmap = ~0ULL >> (64 - get_num_sdma_queues(dqm));
dqm->xgmi_sdma_bitmap = ~0ULL >> (64 - get_num_xgmi_sdma_queues(dqm));
num_sdma_queues = get_num_sdma_queues(dqm);
if (num_sdma_queues >= BITS_PER_TYPE(dqm->sdma_bitmap))
dqm->sdma_bitmap = ULLONG_MAX;
else
dqm->sdma_bitmap = (BIT_ULL(num_sdma_queues) - 1);
num_xgmi_sdma_queues = get_num_xgmi_sdma_queues(dqm);
if (num_xgmi_sdma_queues >= BITS_PER_TYPE(dqm->xgmi_sdma_bitmap))
dqm->xgmi_sdma_bitmap = ULLONG_MAX;
else
dqm->xgmi_sdma_bitmap = (BIT_ULL(num_xgmi_sdma_queues) - 1);
INIT_WORK(&dqm->hw_exception_work, kfd_process_hw_exception);