2020-03-08 09:27:27

by Christophe JAILLET

Subject: [PATCH] drm/amdgpu/display: Fix an error handling path in 'dm_update_crtc_state()'

'dc_stream_release()' may be called twice. Once here, and once below in the
error handling path if we branch to the 'fail' label.

Set 'new_stream' to NULL, once released to avoid the duplicated release
function call.

Signed-off-by: Christophe JAILLET <[email protected]>
---
Maybe the 'goto fail' at line 7745 should be turned into a 'return ret'
instead. Could be clearer.

No Fixes tag provided because I've not been able to dig deep enough in the
git history.
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

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 97c1b01c0fc1..9d7773a77c4f 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -7704,8 +7704,10 @@ static int dm_update_crtc_state(struct amdgpu_display_manager *dm,

skip_modeset:
/* Release extra reference */
- if (new_stream)
- dc_stream_release(new_stream);
+ if (new_stream) {
+ dc_stream_release(new_stream);
+ new_stream = NULL;
+ }

/*
* We want to do dc stream updates that do not require a
--
2.20.1

2020-03-09 08:25:12

by walter harms

Subject: AW: [PATCH] drm/amdgpu/display: Fix an error handling path in 'dm_update_crtc_state()'

________________________________________
Von: [email protected] <[email protected]> im Auftrag von Christophe JAILLET <[email protected]>
Gesendet: Sonntag, 8. M?rz 2020 10:26
An: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]
Cc: [email protected]; [email protected]; [email protected]; [email protected]; Christophe JAILLET
Betreff: [PATCH] drm/amdgpu/display: Fix an error handling path in 'dm_update_crtc_state()'

'dc_stream_release()' may be called twice. Once here, and once below in the
error handling path if we branch to the 'fail' label.

Set 'new_stream' to NULL, once released to avoid the duplicated release
function call.

Signed-off-by: Christophe JAILLET <[email protected]>
---
Maybe the 'goto fail' at line 7745 should be turned into a 'return ret'
instead. Could be clearer.

No Fixes tag provided because I've not been able to dig deep enough in the
git history.
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

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 97c1b01c0fc1..9d7773a77c4f 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -7704,8 +7704,10 @@ static int dm_update_crtc_state(struct amdgpu_display_manager *dm,

skip_modeset:
/* Release extra reference */
- if (new_stream)
- dc_stream_release(new_stream);
+ if (new_stream) {
+ dc_stream_release(new_stream);
+ new_stream = NULL;
+ }


dc_stream_release() is NULL-checked, so the if can be dropped.

re,
wh

/*
* We want to do dc stream updates that do not require a
--
2.20.1

2020-03-12 13:40:03

by Dan Carpenter

Subject: Re: [PATCH] drm/amdgpu/display: Fix an error handling path in 'dm_update_crtc_state()'

On Mon, Mar 09, 2020 at 08:24:04AM +0000, Walter Harms wrote:
>
> ________________________________________
> Von: [email protected] <[email protected]> im Auftrag von Christophe JAILLET <[email protected]>
> Gesendet: Sonntag, 8. M?rz 2020 10:26
> An: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]
> Cc: [email protected]; [email protected]; [email protected]; [email protected]; Christophe JAILLET
> Betreff: [PATCH] drm/amdgpu/display: Fix an error handling path in 'dm_update_crtc_state()'
>
> 'dc_stream_release()' may be called twice. Once here, and once below in the
> error handling path if we branch to the 'fail' label.
>
> Set 'new_stream' to NULL, once released to avoid the duplicated release
> function call.
>
> Signed-off-by: Christophe JAILLET <[email protected]>
> ---
> Maybe the 'goto fail' at line 7745 should be turned into a 'return ret'
> instead. Could be clearer.
>
> No Fixes tag provided because I've not been able to dig deep enough in the
> git history.
> ---
> drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> 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 97c1b01c0fc1..9d7773a77c4f 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -7704,8 +7704,10 @@ static int dm_update_crtc_state(struct amdgpu_display_manager *dm,
>
> skip_modeset:
> /* Release extra reference */
> - if (new_stream)
> - dc_stream_release(new_stream);
> + if (new_stream) {
> + dc_stream_release(new_stream);
> + new_stream = NULL;
> + }
>
>
> dc_stream_release() is NULL-checked, so the if can be dropped.
>
> re,
> wh

Walter, it's really hard to separate your reply from the quoted email.
What's going on with that? Could you configure your email client to
use "> " for the quoted bit?

regards,
dan carpenter