From: Alex Deucher <alexander.deucher@xxxxxxx>
We don't get the right offset in that case. The GPU has
an unused 4K area of the register BAR space into which you can
remap registers. We remap the HDP flush registers into this
space to allow userspace (CPU or GPU) to flush the HDP when it
updates VRAM. However, on systems with >4K pages, we end up
exposing PAGE_SIZE of MMIO space.
Fixes: d8e408a82704 ("drm/amdkfd: Expose HDP registers to user space")
Reviewed-by: Felix Kuehling <felix.kuehling@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
(cherry picked from commit 24e82654e98e96cece5d8b919c522054456eeec6)
Signed-off-by: Felix Kuehling <felix.kuehling@xxxxxxx>
---
drivers/gpu/drm/amd/amdkfd/kfd_chardev.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
index 799a91a064a1..9a444b17530a 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
@@ -1311,7 +1311,7 @@ static int kfd_ioctl_alloc_memory_of_gpu(struct file *filep,
goto err_unlock;
}
offset = amdgpu_amdkfd_get_mmio_remap_phys_addr(dev->kgd);
- if (!offset) {
+ if (!offset || (PAGE_SIZE > 4096)) {
err = -ENOMEM;
goto err_unlock;
}
@@ -1969,6 +1969,9 @@ static int kfd_mmio_mmap(struct kfd_dev *dev, struct kfd_process *process,
if (vma->vm_end - vma->vm_start != PAGE_SIZE)
return -EINVAL;
+ if (PAGE_SIZE > 4096)
+ return -EINVAL;
+
address = amdgpu_amdkfd_get_mmio_remap_phys_addr(dev->kgd);
vma->vm_flags |= VM_IO | VM_DONTCOPY | VM_DONTEXPAND | VM_NORESERVE |
--
2.34.1
