[PATCH] drm/amd/display: Fix white screen page fault for gpuvm

[PATCH] drm/amd/display: Fix white screen page fault for gpuvm

[Nicholas Kazlauskas]

[Why]
The "base_addr_is_mc_addr" field was added for dcn3.1 support but
pa_config was never updated to set it to false.

Uninitialized memory causes it to be set to true which results in
address mistranslation and white screen.

[How]
Use memset to ensure all fields are initialized to 0 by default.

Cc: Aaron Liu <aaron.liu@amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 53363728dbb..b0426bb3f2e 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -1125,6 +1125,8 @@ static void mmhub_read_system_context(struct amdgpu_device *adev, struct dc_phy_
 	uint32_t agp_base, agp_bot, agp_top;
 	PHYSICAL_ADDRESS_LOC page_table_start, page_table_end, page_table_base;
 
+	memset(pa_config, 0, sizeof(*pa_config));
+
 	logical_addr_low  = min(adev->gmc.fb_start, adev->gmc.agp_start) >> 18;
 	pt_base = amdgpu_gmc_pd_addr(adev->gart.bo);
 
-- 
2.25.1

Re: [PATCH] drm/amd/display: Fix white screen page fault for gpuvm

[Alex Deucher]

Acked-by: Alex Deucher <alexander.deucher@amd.com>

Can you add a fixes: tag?

Alex

On Mon, Sep 13, 2021 at 3:11 PM Nicholas Kazlauskas
<nicholas.kazlauskas@amd.com> wrote:
>
> [Why]
> The "base_addr_is_mc_addr" field was added for dcn3.1 support but
> pa_config was never updated to set it to false.
>
> Uninitialized memory causes it to be set to true which results in
> address mistranslation and white screen.
>
> [How]
> Use memset to ensure all fields are initialized to 0 by default.
>
> Cc: Aaron Liu <aaron.liu@amd.com>
> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
> ---
>  drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 53363728dbb..b0426bb3f2e 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -1125,6 +1125,8 @@ static void mmhub_read_system_context(struct amdgpu_device *adev, struct dc_phy_
>         uint32_t agp_base, agp_bot, agp_top;
>         PHYSICAL_ADDRESS_LOC page_table_start, page_table_end, page_table_base;
>
> +       memset(pa_config, 0, sizeof(*pa_config));
> +
>         logical_addr_low  = min(adev->gmc.fb_start, adev->gmc.agp_start) >> 18;
>         pt_base = amdgpu_gmc_pd_addr(adev->gart.bo);
>
> --
> 2.25.1
>

Re: [PATCH] drm/amd/display: Fix white screen page fault for gpuvm

[Kazlauskas, Nicholas]

On 2021-09-13 3:13 p.m., Alex Deucher wrote:
> Acked-by: Alex Deucher <alexander.deucher@amd.com>
> 
> Can you add a fixes: tag?
> 
> Alex

Sure, I think the relevant patch is:

Fixes: 64b1d0e8d50 ("drm/amd/display: Add DCN3.1 HWSEQ")

Regards,
Nicholas Kazlauskas

> 
> On Mon, Sep 13, 2021 at 3:11 PM Nicholas Kazlauskas
> <nicholas.kazlauskas@amd.com> wrote:
>>
>> [Why]
>> The "base_addr_is_mc_addr" field was added for dcn3.1 support but
>> pa_config was never updated to set it to false.
>>
>> Uninitialized memory causes it to be set to true which results in
>> address mistranslation and white screen.
>>
>> [How]
>> Use memset to ensure all fields are initialized to 0 by default.
>>
>> Cc: Aaron Liu <aaron.liu@amd.com>
>> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
>> ---
>>   drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> index 53363728dbb..b0426bb3f2e 100644
>> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> @@ -1125,6 +1125,8 @@ static void mmhub_read_system_context(struct amdgpu_device *adev, struct dc_phy_
>>          uint32_t agp_base, agp_bot, agp_top;
>>          PHYSICAL_ADDRESS_LOC page_table_start, page_table_end, page_table_base;
>>
>> +       memset(pa_config, 0, sizeof(*pa_config));
>> +
>>          logical_addr_low  = min(adev->gmc.fb_start, adev->gmc.agp_start) >> 18;
>>          pt_base = amdgpu_gmc_pd_addr(adev->gart.bo);
>>
>> --
>> 2.25.1
>>

RE: [PATCH] drm/amd/display: Fix white screen page fault for gpuvm

[Liu, Aaron]

[AMD Official Use Only]

Verified on Yellow Carp.
Acked-by: Aaron Liu <aaron.liu@amd.com>

--
Best Regards
Aaron Liu

> -----Original Message-----
> From: Kazlauskas, Nicholas <Nicholas.Kazlauskas@amd.com>
> Sent: Tuesday, September 14, 2021 3:26 AM
> To: Alex Deucher <alexdeucher@gmail.com>
> Cc: amd-gfx list <amd-gfx@lists.freedesktop.org>; Liu, Aaron
> <Aaron.Liu@amd.com>
> Subject: Re: [PATCH] drm/amd/display: Fix white screen page fault for
> gpuvm
> 
> On 2021-09-13 3:13 p.m., Alex Deucher wrote:
> > Acked-by: Alex Deucher <alexander.deucher@amd.com>
> >
> > Can you add a fixes: tag?
> >
> > Alex
> 
> Sure, I think the relevant patch is:
> 
> Fixes: 64b1d0e8d50 ("drm/amd/display: Add DCN3.1 HWSEQ")
> 
> Regards,
> Nicholas Kazlauskas
> 
> >
> > On Mon, Sep 13, 2021 at 3:11 PM Nicholas Kazlauskas
> > <nicholas.kazlauskas@amd.com> wrote:
> >>
> >> [Why]
> >> The "base_addr_is_mc_addr" field was added for dcn3.1 support but
> >> pa_config was never updated to set it to false.
> >>
> >> Uninitialized memory causes it to be set to true which results in
> >> address mistranslation and white screen.
> >>
> >> [How]
> >> Use memset to ensure all fields are initialized to 0 by default.
> >>
> >> Cc: Aaron Liu <aaron.liu@amd.com>
> >> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
> >> ---
> >>   drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 ++
> >>   1 file changed, 2 insertions(+)
> >>
> >> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> >> b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> >> index 53363728dbb..b0426bb3f2e 100644
> >> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> >> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> >> @@ -1125,6 +1125,8 @@ static void
> mmhub_read_system_context(struct amdgpu_device *adev, struct dc_phy_
> >>          uint32_t agp_base, agp_bot, agp_top;
> >>          PHYSICAL_ADDRESS_LOC page_table_start, page_table_end,
> >> page_table_base;
> >>
> >> +       memset(pa_config, 0, sizeof(*pa_config));
> >> +
> >>          logical_addr_low  = min(adev->gmc.fb_start, adev->gmc.agp_start) >>
> 18;
> >>          pt_base = amdgpu_gmc_pd_addr(adev->gart.bo);
> >>
> >> --
> >> 2.25.1
> >>

Re: [PATCH] drm/amd/display: Fix white screen page fault for gpuvm

[Harry Wentland]

On 2021-09-13 15:11, Nicholas Kazlauskas wrote:
> [Why]
> The "base_addr_is_mc_addr" field was added for dcn3.1 support but
> pa_config was never updated to set it to false.
> 
> Uninitialized memory causes it to be set to true which results in
> address mistranslation and white screen.
> 
> [How]
> Use memset to ensure all fields are initialized to 0 by default.
> 
> Cc: Aaron Liu <aaron.liu@amd.com>
> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>

Reviewed-by: Harry Wentland <harry.wentland@amd.com>

Harry

> ---
>  drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 53363728dbb..b0426bb3f2e 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -1125,6 +1125,8 @@ static void mmhub_read_system_context(struct amdgpu_device *adev, struct dc_phy_
>  	uint32_t agp_base, agp_bot, agp_top;
>  	PHYSICAL_ADDRESS_LOC page_table_start, page_table_end, page_table_base;
>  
> +	memset(pa_config, 0, sizeof(*pa_config));
> +
>  	logical_addr_low  = min(adev->gmc.fb_start, adev->gmc.agp_start) >> 18;
>  	pt_base = amdgpu_gmc_pd_addr(adev->gart.bo);
>  
>