gpu: nvgpu: Use real PDE size to determine pte_blk_order

In the buddy allocator use the actual size of the PDE to determine
the pte_blk_order field which is used to determine what page size a
buddy has (or doesn't). Previously this was just set as the large
page size times 1024 which would over allocate PDE ranges for Pascal+
chips. This caused userspace, which was using the real PDE size, to
sometime allocate small and large pages in what the buddy allocator
mistakenly thought was one PDE.

Bug 200105199

Change-Id: I7ab7db7962015fc268bad61b558a18704133e1cb
Signed-off-by: Alex Waterman <alexw@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1639731
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/common/mm/buddy_allocator.c b/drivers/gpu/nvgpu/common/mm/buddy_allocator.c
index a2546e9d..e5a9b62b 100644
--- a/drivers/gpu/nvgpu/common/mm/buddy_allocator.c
+++ b/drivers/gpu/nvgpu/common/mm/buddy_allocator.c
@@ -1255,7 +1255,7 @@ int __nvgpu_buddy_allocator_init(struct gk20a *g, struct nvgpu_allocator *__a,
 
         a->vm = vm;
         if (flags & GPU_ALLOC_GVA_SPACE) {
-                pde_size = ((u64)vm->big_page_size) << 10;
+                pde_size = 1ULL << nvgpu_vm_pde_coverage_bit_count(vm);
                 a->pte_blk_order = balloc_get_order(a, pde_size);
         }