drm/amdgpu: disable gfxoff when using register read interface

When gfxoff is enabled, accessing gfx registers via MMIO
can lead to a hang.

Bug: https://bugzilla.kernel.org/show_bug.cgi?id=205497
Acked-by: Xiaojie Yuan <xiaojie.yuan@amd.com>
Reviewed-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Alex Deucher 2019-11-14 11:39:05 -05:00
parent dda0f4558c
commit 70f7eb639e
1 changed files with 5 additions and 1 deletions

View File

@ -655,15 +655,19 @@ static int amdgpu_info_ioctl(struct drm_device *dev, void *data, struct drm_file
return -ENOMEM;
alloc_size = info->read_mmr_reg.count * sizeof(*regs);
for (i = 0; i < info->read_mmr_reg.count; i++)
amdgpu_gfx_off_ctrl(adev, false);
for (i = 0; i < info->read_mmr_reg.count; i++) {
if (amdgpu_asic_read_register(adev, se_num, sh_num,
info->read_mmr_reg.dword_offset + i,
&regs[i])) {
DRM_DEBUG_KMS("unallowed offset %#x\n",
info->read_mmr_reg.dword_offset + i);
kfree(regs);
amdgpu_gfx_off_ctrl(adev, true);
return -EFAULT;
}
}
amdgpu_gfx_off_ctrl(adev, true);
n = copy_to_user(out, regs, min(size, alloc_size));
kfree(regs);
return n ? -EFAULT : 0;