clang reportes this error
drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2322:8: error:
variable 'possible_crtcs' is used uninitialized whenever 'if'
condition is false [-Werror,-Wsometimes-uninitialized]
if (vp) {
^~
drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2336:36: note:
uninitialized use occurs here
ret = vop2_plane_init(vop2, win, possible_crtcs);
^~~~~~~~~~~~~~
drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2322:4:
note: remove the 'if' if its condition is always true
if (vp) {
^~~~~~~~
The else-statement changes the win->type to OVERLAY without setting the
possible_crtcs variable. Rework the block, initialize possible_crtcs to
0 to remove the else-statement. Split the else-if-statement out to its
own if-statement so the OVERLAY check will catch when the win-type has
been changed.
Fixes: 368419a2d429 ("drm/rockchip: vop2: initialize possible_crtcs properly")
Signed-off-by: Tom Rix <[email protected]>
---
drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
index 03ca32cd2050..fce992c3506f 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
@@ -2301,7 +2301,7 @@ static int vop2_create_crtcs(struct vop2 *vop2)
nvp = 0;
for (i = 0; i < vop2->registered_num_wins; i++) {
struct vop2_win *win = &vop2->win[i];
- u32 possible_crtcs;
+ u32 possible_crtcs = 0;
if (vop2->data->soc_id == 3566) {
/*
@@ -2327,12 +2327,11 @@ static int vop2_create_crtcs(struct vop2 *vop2)
/* change the unused primary window to overlay window */
win->type = DRM_PLANE_TYPE_OVERLAY;
}
- } else if (win->type == DRM_PLANE_TYPE_OVERLAY) {
- possible_crtcs = (1 << nvps) - 1;
- } else {
- possible_crtcs = 0;
}
+ if (win->type == DRM_PLANE_TYPE_OVERLAY)
+ possible_crtcs = (1 << nvps) - 1;
+
ret = vop2_plane_init(vop2, win, possible_crtcs);
if (ret) {
drm_err(vop2->drm, "failed to init plane %s: %d\n",
--
2.27.0
Am Donnerstag, 16. M?rz 2023, 14:23:02 CET schrieb Tom Rix:
> clang reportes this error
> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2322:8: error:
> variable 'possible_crtcs' is used uninitialized whenever 'if'
> condition is false [-Werror,-Wsometimes-uninitialized]
> if (vp) {
> ^~
> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2336:36: note:
> uninitialized use occurs here
> ret = vop2_plane_init(vop2, win, possible_crtcs);
> ^~~~~~~~~~~~~~
> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2322:4:
> note: remove the 'if' if its condition is always true
> if (vp) {
> ^~~~~~~~
>
> The else-statement changes the win->type to OVERLAY without setting the
> possible_crtcs variable. Rework the block, initialize possible_crtcs to
> 0 to remove the else-statement. Split the else-if-statement out to its
> own if-statement so the OVERLAY check will catch when the win-type has
> been changed.
>
> Fixes: 368419a2d429 ("drm/rockchip: vop2: initialize possible_crtcs properly")
> Signed-off-by: Tom Rix <[email protected]>
> ---
> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 9 ++++-----
> 1 file changed, 4 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> index 03ca32cd2050..fce992c3506f 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> @@ -2301,7 +2301,7 @@ static int vop2_create_crtcs(struct vop2 *vop2)
> nvp = 0;
> for (i = 0; i < vop2->registered_num_wins; i++) {
> struct vop2_win *win = &vop2->win[i];
> - u32 possible_crtcs;
> + u32 possible_crtcs = 0;
>
> if (vop2->data->soc_id == 3566) {
> /*
> @@ -2327,12 +2327,11 @@ static int vop2_create_crtcs(struct vop2 *vop2)
> /* change the unused primary window to overlay window */
> win->type = DRM_PLANE_TYPE_OVERLAY;
> }
> - } else if (win->type == DRM_PLANE_TYPE_OVERLAY) {
> - possible_crtcs = (1 << nvps) - 1;
> - } else {
> - possible_crtcs = 0;
> }
>
> + if (win->type == DRM_PLANE_TYPE_OVERLAY)
> + possible_crtcs = (1 << nvps) - 1;
> +
After a long hard stare at the code in question, I think doing it this
way looks like the correct one, as as you mention in the commit message
the first "if" will change the win->type to OVERLAY in one case, but this
then will never be added.
Michael, do you agree/disagree?
Thanks
Heiko
https://lore.kernel.org/r/[email protected]
> ret = vop2_plane_init(vop2, win, possible_crtcs);
> if (ret) {
> drm_err(vop2->drm, "failed to init plane %s: %d\n",
>
Hi Tom, Heiko,
On 3/16/23 15:05, Heiko Stuebner wrote:
> Am Donnerstag, 16. März 2023, 14:23:02 CET schrieb Tom Rix:
>> clang reportes this error
>> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2322:8: error:
>> variable 'possible_crtcs' is used uninitialized whenever 'if'
>> condition is false [-Werror,-Wsometimes-uninitialized]
>> if (vp) {
>> ^~
>> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2336:36: note:
>> uninitialized use occurs here
>> ret = vop2_plane_init(vop2, win, possible_crtcs);
>> ^~~~~~~~~~~~~~
>> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2322:4:
>> note: remove the 'if' if its condition is always true
>> if (vp) {
>> ^~~~~~~~
>>
>> The else-statement changes the win->type to OVERLAY without setting the
>> possible_crtcs variable. Rework the block, initialize possible_crtcs to
>> 0 to remove the else-statement. Split the else-if-statement out to its
>> own if-statement so the OVERLAY check will catch when the win-type has
>> been changed.
>>
>> Fixes: 368419a2d429 ("drm/rockchip: vop2: initialize possible_crtcs properly")
>> Signed-off-by: Tom Rix <[email protected]>
>> ---
>> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 9 ++++-----
>> 1 file changed, 4 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
>> index 03ca32cd2050..fce992c3506f 100644
>> --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
>> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
>> @@ -2301,7 +2301,7 @@ static int vop2_create_crtcs(struct vop2 *vop2)
>> nvp = 0;
>> for (i = 0; i < vop2->registered_num_wins; i++) {
>> struct vop2_win *win = &vop2->win[i];
>> - u32 possible_crtcs;
>> + u32 possible_crtcs = 0;
>>
>> if (vop2->data->soc_id == 3566) {
>> /*
>> @@ -2327,12 +2327,11 @@ static int vop2_create_crtcs(struct vop2 *vop2)
>> /* change the unused primary window to overlay window */
>> win->type = DRM_PLANE_TYPE_OVERLAY;
>> }
>> - } else if (win->type == DRM_PLANE_TYPE_OVERLAY) {
>> - possible_crtcs = (1 << nvps) - 1;
>> - } else {
>> - possible_crtcs = 0;
>> }
>>
>> + if (win->type == DRM_PLANE_TYPE_OVERLAY)
>> + possible_crtcs = (1 << nvps) - 1;
>> +
>
> After a long hard stare at the code in question, I think doing it this
> way looks like the correct one, as as you mention in the commit message
> the first "if" will change the win->type to OVERLAY in one case, but this
> then will never be added.
>
> Michael, do you agree/disagree?
Shoot, this bit of code is more complicated than I believed it would be.
Yes, Tom's patch makes sense to me. But having overlooked the win->type
change in the if-clause makes me think I shouldn't be the judge of that
:-) Still,
Acked-by: Michael Riesch <[email protected]>
Thanks for fixing it and best regards,
Michael
>
>
> Thanks
> Heiko
>
> https://lore.kernel.org/r/[email protected]
>
>> ret = vop2_plane_init(vop2, win, possible_crtcs);
>> if (ret) {
>> drm_err(vop2->drm, "failed to init plane %s: %d\n",
>>
>
>
>
>
On Thu, Mar 16, 2023 at 09:23:02AM -0400, Tom Rix wrote:
> clang reportes this error
> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2322:8: error:
> variable 'possible_crtcs' is used uninitialized whenever 'if'
> condition is false [-Werror,-Wsometimes-uninitialized]
> if (vp) {
> ^~
> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2336:36: note:
> uninitialized use occurs here
> ret = vop2_plane_init(vop2, win, possible_crtcs);
> ^~~~~~~~~~~~~~
> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2322:4:
> note: remove the 'if' if its condition is always true
> if (vp) {
> ^~~~~~~~
>
> The else-statement changes the win->type to OVERLAY without setting the
> possible_crtcs variable. Rework the block, initialize possible_crtcs to
> 0 to remove the else-statement. Split the else-if-statement out to its
> own if-statement so the OVERLAY check will catch when the win-type has
> been changed.
>
> Fixes: 368419a2d429 ("drm/rockchip: vop2: initialize possible_crtcs properly")
> Signed-off-by: Tom Rix <[email protected]>
Reviewed-by: Nathan Chancellor <[email protected]>
> ---
> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 9 ++++-----
> 1 file changed, 4 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> index 03ca32cd2050..fce992c3506f 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> @@ -2301,7 +2301,7 @@ static int vop2_create_crtcs(struct vop2 *vop2)
> nvp = 0;
> for (i = 0; i < vop2->registered_num_wins; i++) {
> struct vop2_win *win = &vop2->win[i];
> - u32 possible_crtcs;
> + u32 possible_crtcs = 0;
>
> if (vop2->data->soc_id == 3566) {
> /*
> @@ -2327,12 +2327,11 @@ static int vop2_create_crtcs(struct vop2 *vop2)
> /* change the unused primary window to overlay window */
> win->type = DRM_PLANE_TYPE_OVERLAY;
> }
> - } else if (win->type == DRM_PLANE_TYPE_OVERLAY) {
> - possible_crtcs = (1 << nvps) - 1;
> - } else {
> - possible_crtcs = 0;
> }
>
> + if (win->type == DRM_PLANE_TYPE_OVERLAY)
> + possible_crtcs = (1 << nvps) - 1;
> +
> ret = vop2_plane_init(vop2, win, possible_crtcs);
> if (ret) {
> drm_err(vop2->drm, "failed to init plane %s: %d\n",
> --
> 2.27.0
>
On Thu, 16 Mar 2023 09:23:02 -0400, Tom Rix wrote:
> clang reportes this error
> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2322:8: error:
> variable 'possible_crtcs' is used uninitialized whenever 'if'
> condition is false [-Werror,-Wsometimes-uninitialized]
> if (vp) {
> ^~
> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2336:36: note:
> uninitialized use occurs here
> ret = vop2_plane_init(vop2, win, possible_crtcs);
> ^~~~~~~~~~~~~~
> drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2322:4:
> note: remove the 'if' if its condition is always true
> if (vp) {
> ^~~~~~~~
>
> [...]
Applied, thanks!
[1/1] drm/rockchip: vop2: fix uninitialized variable possible_crtcs
commit: e88adb4ac27a37de4167150b8a6a736d40cf7018
Best regards,
--
Heiko Stuebner <[email protected]>