[PATCH AUTOSEL 6.8 40/43] drm/xe/xe_migrate: Cast to output precision before multiplying operands

Sasha Levin
2024-04-22T23:55:40Z

From: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>

[ Upstream commit 9cb46b31f3d08ed3fce86349e8c12f96d7c88717 ]

Addressing potential overflow in result of multiplication of two lower
precision (u32) operands before widening it to higher precision
(u64).

-v2
Fix commit message and description. (Rodrigo)

Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240401175300.3823653-1-himal.prasad.ghimiray@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
(cherry picked from commit 34820967ae7b45411f8f4f737c2d63b0c608e0d7)
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/xe/xe_migrate.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c
index 70480c3056021..7a6ad3469d748 100644
--- a/drivers/gpu/drm/xe/xe_migrate.c
+++ b/drivers/gpu/drm/xe/xe_migrate.c
@@ -216,7 +216,7 @@ static int xe_migrate_prepare_vm(struct xe_tile *tile, struct xe_migrate *m,
if (vm->flags & XE_VM_FLAG_64K && level == 1)
flags = XE_PDE_64K;

- entry = vm->pt_ops->pde_encode_bo(bo, map_ofs + (level - 1) *
+ entry = vm->pt_ops->pde_encode_bo(bo, map_ofs + (u64)(level - 1) *
XE_PAGE_SIZE, pat_index);
xe_map_wr(xe, &bo->vmap, map_ofs + XE_PAGE_SIZE * level, u64,
entry | flags);
@@ -224,7 +224,7 @@ static int xe_migrate_prepare_vm(struct xe_tile *tile, struct xe_migrate *m,

/* Write PDE's that point to our BO. */
for (i = 0; i < num_entries - num_level; i++) {
- entry = vm->pt_ops->pde_encode_bo(bo, i * XE_PAGE_SIZE,
+ entry = vm->pt_ops->pde_encode_bo(bo, (u64)i * XE_PAGE_SIZE,
pat_index);

xe_map_wr(xe, &bo->vmap, map_ofs + XE_PAGE_SIZE +
@@ -280,7 +280,7 @@ static int xe_migrate_prepare_vm(struct xe_tile *tile, struct xe_migrate *m,
#define VM_SA_UPDATE_UNIT_SIZE (XE_PAGE_SIZE / NUM_VMUSA_UNIT_PER_PAGE)
#define NUM_VMUSA_WRITES_PER_UNIT (VM_SA_UPDATE_UNIT_SIZE / sizeof(u64))
drm_suballoc_manager_init(&m->vm_update_sa,
- (map_ofs / XE_PAGE_SIZE - NUM_KERNEL_PDE) *
+ (size_t)(map_ofs / XE_PAGE_SIZE - NUM_KERNEL_PDE) *
NUM_VMUSA_UNIT_PER_PAGE, 0);

m->pt_bo = bo;
@@ -479,7 +479,7 @@ static void emit_pte(struct xe_migrate *m,
struct xe_vm *vm = m->q->vm;
u16 pat_index;
u32 ptes;
- u64 ofs = at_pt * XE_PAGE_SIZE;
+ u64 ofs = (u64)at_pt * XE_PAGE_SIZE;
u64 cur_ofs;

/* Indirect access needs compression enabled uncached PAT index */
--
2.43.0