* [PATCH] drm/amd/display: Add NULL checks for vblank workqueue
@ 2021-09-07 14:10 Nicholas Kazlauskas
2021-09-07 14:20 ` Harry Wentland
0 siblings, 1 reply; 5+ messages in thread
From: Nicholas Kazlauskas @ 2021-09-07 14:10 UTC (permalink / raw)
To: amd-gfx
Cc: Nicholas Kazlauskas, Roman Li, Wayne Lin, Harry Wentland, Mike Lothian
[Why]
If we're running a headless config with 0 links then the vblank
workqueue will be NULL - causing a NULL pointer exception during
any commit.
[How]
Guard access to the workqueue if it's NULL and don't queue or flush
work if it is.
Cc: Roman Li <Roman.Li@amd.com>
Cc: Wayne Lin <Wayne.Lin@amd.com>
Cc: Harry Wentland <Harry.Wentland@amd.com>
Reported-by: Mike Lothian <mike@fireburn.co.uk>
BugLink: https://gitlab.freedesktop.org/drm/amd/-/issues/1700
Fixes: 91f86d4cce2 ("drm/amd/display: Use vblank control events for PSR enable/disable")
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
---
.../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 32 +++++++++++--------
1 file changed, 18 insertions(+), 14 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 8837259215d..46e08736f94 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -6185,21 +6185,23 @@ static inline int dm_set_vblank(struct drm_crtc *crtc, bool enable)
return 0;
#if defined(CONFIG_DRM_AMD_DC_DCN)
- work = kzalloc(sizeof(*work), GFP_ATOMIC);
- if (!work)
- return -ENOMEM;
+ if (dm->vblank_control_workqueue) {
+ work = kzalloc(sizeof(*work), GFP_ATOMIC);
+ if (!work)
+ return -ENOMEM;
- INIT_WORK(&work->work, vblank_control_worker);
- work->dm = dm;
- work->acrtc = acrtc;
- work->enable = enable;
+ INIT_WORK(&work->work, vblank_control_worker);
+ work->dm = dm;
+ work->acrtc = acrtc;
+ work->enable = enable;
- if (acrtc_state->stream) {
- dc_stream_retain(acrtc_state->stream);
- work->stream = acrtc_state->stream;
- }
+ if (acrtc_state->stream) {
+ dc_stream_retain(acrtc_state->stream);
+ work->stream = acrtc_state->stream;
+ }
- queue_work(dm->vblank_control_workqueue, &work->work);
+ queue_work(dm->vblank_control_workqueue, &work->work);
+ }
#endif
return 0;
@@ -8809,7 +8811,8 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
* If PSR or idle optimizations are enabled then flush out
* any pending work before hardware programming.
*/
- flush_workqueue(dm->vblank_control_workqueue);
+ if (dm->vblank_control_workqueue)
+ flush_workqueue(dm->vblank_control_workqueue);
#endif
bundle->stream_update.stream = acrtc_state->stream;
@@ -9144,7 +9147,8 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state)
/* if there mode set or reset, disable eDP PSR */
if (mode_set_reset_required) {
#if defined(CONFIG_DRM_AMD_DC_DCN)
- flush_workqueue(dm->vblank_control_workqueue);
+ if (dm->vblank_control_workqueue)
+ flush_workqueue(dm->vblank_control_workqueue);
#endif
amdgpu_dm_psr_disable_all(dm);
}
--
2.25.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] drm/amd/display: Add NULL checks for vblank workqueue
2021-09-07 14:10 [PATCH] drm/amd/display: Add NULL checks for vblank workqueue Nicholas Kazlauskas
@ 2021-09-07 14:20 ` Harry Wentland
2021-09-08 1:41 ` Mike Lothian
0 siblings, 1 reply; 5+ messages in thread
From: Harry Wentland @ 2021-09-07 14:20 UTC (permalink / raw)
To: Nicholas Kazlauskas, amd-gfx; +Cc: Roman Li, Wayne Lin, Mike Lothian
On 2021-09-07 10:10 a.m., Nicholas Kazlauskas wrote:
> [Why]
> If we're running a headless config with 0 links then the vblank
> workqueue will be NULL - causing a NULL pointer exception during
> any commit.
>
> [How]
> Guard access to the workqueue if it's NULL and don't queue or flush
> work if it is.
>
> Cc: Roman Li <Roman.Li@amd.com>
> Cc: Wayne Lin <Wayne.Lin@amd.com>
> Cc: Harry Wentland <Harry.Wentland@amd.com>
> Reported-by: Mike Lothian <mike@fireburn.co.uk>
> BugLink: https://gitlab.freedesktop.org/drm/amd/-/issues/1700
> Fixes: 91f86d4cce2 ("drm/amd/display: Use vblank control events for PSR enable/disable")
> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Harry
> ---
> .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 32 +++++++++++--------
> 1 file changed, 18 insertions(+), 14 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 8837259215d..46e08736f94 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -6185,21 +6185,23 @@ static inline int dm_set_vblank(struct drm_crtc *crtc, bool enable)
> return 0;
>
> #if defined(CONFIG_DRM_AMD_DC_DCN)
> - work = kzalloc(sizeof(*work), GFP_ATOMIC);
> - if (!work)
> - return -ENOMEM;
> + if (dm->vblank_control_workqueue) {
> + work = kzalloc(sizeof(*work), GFP_ATOMIC);
> + if (!work)
> + return -ENOMEM;
>
> - INIT_WORK(&work->work, vblank_control_worker);
> - work->dm = dm;
> - work->acrtc = acrtc;
> - work->enable = enable;
> + INIT_WORK(&work->work, vblank_control_worker);
> + work->dm = dm;
> + work->acrtc = acrtc;
> + work->enable = enable;
>
> - if (acrtc_state->stream) {
> - dc_stream_retain(acrtc_state->stream);
> - work->stream = acrtc_state->stream;
> - }
> + if (acrtc_state->stream) {
> + dc_stream_retain(acrtc_state->stream);
> + work->stream = acrtc_state->stream;
> + }
>
> - queue_work(dm->vblank_control_workqueue, &work->work);
> + queue_work(dm->vblank_control_workqueue, &work->work);
> + }
> #endif
>
> return 0;
> @@ -8809,7 +8811,8 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
> * If PSR or idle optimizations are enabled then flush out
> * any pending work before hardware programming.
> */
> - flush_workqueue(dm->vblank_control_workqueue);
> + if (dm->vblank_control_workqueue)
> + flush_workqueue(dm->vblank_control_workqueue);
> #endif
>
> bundle->stream_update.stream = acrtc_state->stream;
> @@ -9144,7 +9147,8 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state)
> /* if there mode set or reset, disable eDP PSR */
> if (mode_set_reset_required) {
> #if defined(CONFIG_DRM_AMD_DC_DCN)
> - flush_workqueue(dm->vblank_control_workqueue);
> + if (dm->vblank_control_workqueue)
> + flush_workqueue(dm->vblank_control_workqueue);
> #endif
> amdgpu_dm_psr_disable_all(dm);
> }
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] drm/amd/display: Add NULL checks for vblank workqueue
2021-09-07 14:20 ` Harry Wentland
@ 2021-09-08 1:41 ` Mike Lothian
2021-09-09 19:16 ` Harry Wentland
2021-09-13 18:57 ` Alex Deucher
0 siblings, 2 replies; 5+ messages in thread
From: Mike Lothian @ 2021-09-08 1:41 UTC (permalink / raw)
To: Harry Wentland; +Cc: Nicholas Kazlauskas, amd-gfx list, Roman Li, Wayne Lin
Hi
I've just tested this out against Linus's tree and it seems to fix things
Out of interest does Tonga have GPU reset when things go wrong?
Thanks
Mike
On Tue, 7 Sept 2021 at 15:20, Harry Wentland <harry.wentland@amd.com> wrote:
>
>
>
> On 2021-09-07 10:10 a.m., Nicholas Kazlauskas wrote:
> > [Why]
> > If we're running a headless config with 0 links then the vblank
> > workqueue will be NULL - causing a NULL pointer exception during
> > any commit.
> >
> > [How]
> > Guard access to the workqueue if it's NULL and don't queue or flush
> > work if it is.
> >
> > Cc: Roman Li <Roman.Li@amd.com>
> > Cc: Wayne Lin <Wayne.Lin@amd.com>
> > Cc: Harry Wentland <Harry.Wentland@amd.com>
> > Reported-by: Mike Lothian <mike@fireburn.co.uk>
> > BugLink: https://gitlab.freedesktop.org/drm/amd/-/issues/1700
> > Fixes: 91f86d4cce2 ("drm/amd/display: Use vblank control events for PSR enable/disable")
> > Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
>
> Reviewed-by: Harry Wentland <harry.wentland@amd.com>
>
> Harry
>
> > ---
> > .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 32 +++++++++++--------
> > 1 file changed, 18 insertions(+), 14 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 8837259215d..46e08736f94 100644
> > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> > @@ -6185,21 +6185,23 @@ static inline int dm_set_vblank(struct drm_crtc *crtc, bool enable)
> > return 0;
> >
> > #if defined(CONFIG_DRM_AMD_DC_DCN)
> > - work = kzalloc(sizeof(*work), GFP_ATOMIC);
> > - if (!work)
> > - return -ENOMEM;
> > + if (dm->vblank_control_workqueue) {
> > + work = kzalloc(sizeof(*work), GFP_ATOMIC);
> > + if (!work)
> > + return -ENOMEM;
> >
> > - INIT_WORK(&work->work, vblank_control_worker);
> > - work->dm = dm;
> > - work->acrtc = acrtc;
> > - work->enable = enable;
> > + INIT_WORK(&work->work, vblank_control_worker);
> > + work->dm = dm;
> > + work->acrtc = acrtc;
> > + work->enable = enable;
> >
> > - if (acrtc_state->stream) {
> > - dc_stream_retain(acrtc_state->stream);
> > - work->stream = acrtc_state->stream;
> > - }
> > + if (acrtc_state->stream) {
> > + dc_stream_retain(acrtc_state->stream);
> > + work->stream = acrtc_state->stream;
> > + }
> >
> > - queue_work(dm->vblank_control_workqueue, &work->work);
> > + queue_work(dm->vblank_control_workqueue, &work->work);
> > + }
> > #endif
> >
> > return 0;
> > @@ -8809,7 +8811,8 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
> > * If PSR or idle optimizations are enabled then flush out
> > * any pending work before hardware programming.
> > */
> > - flush_workqueue(dm->vblank_control_workqueue);
> > + if (dm->vblank_control_workqueue)
> > + flush_workqueue(dm->vblank_control_workqueue);
> > #endif
> >
> > bundle->stream_update.stream = acrtc_state->stream;
> > @@ -9144,7 +9147,8 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state)
> > /* if there mode set or reset, disable eDP PSR */
> > if (mode_set_reset_required) {
> > #if defined(CONFIG_DRM_AMD_DC_DCN)
> > - flush_workqueue(dm->vblank_control_workqueue);
> > + if (dm->vblank_control_workqueue)
> > + flush_workqueue(dm->vblank_control_workqueue);
> > #endif
> > amdgpu_dm_psr_disable_all(dm);
> > }
> >
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] drm/amd/display: Add NULL checks for vblank workqueue
2021-09-08 1:41 ` Mike Lothian
@ 2021-09-09 19:16 ` Harry Wentland
2021-09-13 18:57 ` Alex Deucher
1 sibling, 0 replies; 5+ messages in thread
From: Harry Wentland @ 2021-09-09 19:16 UTC (permalink / raw)
To: Mike Lothian, Deucher, Alexander
Cc: Nicholas Kazlauskas, amd-gfx list, Roman Li, Wayne Lin
On 2021-09-07 9:41 p.m., Mike Lothian wrote:
> Hi
>
> I've just tested this out against Linus's tree and it seems to fix things
>
Thanks.
> Out of interest does Tonga have GPU reset when things go wrong?
>
Not sure. Alex might know.
Harry
> Thanks
>
> Mike
>
> On Tue, 7 Sept 2021 at 15:20, Harry Wentland <harry.wentland@amd.com> wrote:
>>
>>
>>
>> On 2021-09-07 10:10 a.m., Nicholas Kazlauskas wrote:
>>> [Why]
>>> If we're running a headless config with 0 links then the vblank
>>> workqueue will be NULL - causing a NULL pointer exception during
>>> any commit.
>>>
>>> [How]
>>> Guard access to the workqueue if it's NULL and don't queue or flush
>>> work if it is.
>>>
>>> Cc: Roman Li <Roman.Li@amd.com>
>>> Cc: Wayne Lin <Wayne.Lin@amd.com>
>>> Cc: Harry Wentland <Harry.Wentland@amd.com>
>>> Reported-by: Mike Lothian <mike@fireburn.co.uk>
>>> BugLink: https://gitlab.freedesktop.org/drm/amd/-/issues/1700>>>> Fixes: 91f86d4cce2 ("drm/amd/display: Use vblank control events for PSR enable/disable")
>>> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
>>
>> Reviewed-by: Harry Wentland <harry.wentland@amd.com>
>>
>> Harry
>>
>>> ---
>>> .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 32 +++++++++++--------
>>> 1 file changed, 18 insertions(+), 14 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 8837259215d..46e08736f94 100644
>>> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>>> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>>> @@ -6185,21 +6185,23 @@ static inline int dm_set_vblank(struct drm_crtc *crtc, bool enable)
>>> return 0;
>>>
>>> #if defined(CONFIG_DRM_AMD_DC_DCN)
>>> - work = kzalloc(sizeof(*work), GFP_ATOMIC);
>>> - if (!work)
>>> - return -ENOMEM;
>>> + if (dm->vblank_control_workqueue) {
>>> + work = kzalloc(sizeof(*work), GFP_ATOMIC);
>>> + if (!work)
>>> + return -ENOMEM;
>>>
>>> - INIT_WORK(&work->work, vblank_control_worker);
>>> - work->dm = dm;
>>> - work->acrtc = acrtc;
>>> - work->enable = enable;
>>> + INIT_WORK(&work->work, vblank_control_worker);
>>> + work->dm = dm;
>>> + work->acrtc = acrtc;
>>> + work->enable = enable;
>>>
>>> - if (acrtc_state->stream) {
>>> - dc_stream_retain(acrtc_state->stream);
>>> - work->stream = acrtc_state->stream;
>>> - }
>>> + if (acrtc_state->stream) {
>>> + dc_stream_retain(acrtc_state->stream);
>>> + work->stream = acrtc_state->stream;
>>> + }
>>>
>>> - queue_work(dm->vblank_control_workqueue, &work->work);
>>> + queue_work(dm->vblank_control_workqueue, &work->work);
>>> + }
>>> #endif
>>>
>>> return 0;
>>> @@ -8809,7 +8811,8 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
>>> * If PSR or idle optimizations are enabled then flush out
>>> * any pending work before hardware programming.
>>> */
>>> - flush_workqueue(dm->vblank_control_workqueue);
>>> + if (dm->vblank_control_workqueue)
>>> + flush_workqueue(dm->vblank_control_workqueue);
>>> #endif
>>>
>>> bundle->stream_update.stream = acrtc_state->stream;
>>> @@ -9144,7 +9147,8 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state)
>>> /* if there mode set or reset, disable eDP PSR */
>>> if (mode_set_reset_required) {
>>> #if defined(CONFIG_DRM_AMD_DC_DCN)
>>> - flush_workqueue(dm->vblank_control_workqueue);
>>> + if (dm->vblank_control_workqueue)
>>> + flush_workqueue(dm->vblank_control_workqueue);
>>> #endif
>>> amdgpu_dm_psr_disable_all(dm);
>>> }
>>>
>>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] drm/amd/display: Add NULL checks for vblank workqueue
2021-09-08 1:41 ` Mike Lothian
2021-09-09 19:16 ` Harry Wentland
@ 2021-09-13 18:57 ` Alex Deucher
1 sibling, 0 replies; 5+ messages in thread
From: Alex Deucher @ 2021-09-13 18:57 UTC (permalink / raw)
To: Mike Lothian
Cc: Harry Wentland, Nicholas Kazlauskas, amd-gfx list, Roman Li, Wayne Lin
On Tue, Sep 7, 2021 at 9:42 PM Mike Lothian <mike@fireburn.co.uk> wrote:
>
> Hi
>
> I've just tested this out against Linus's tree and it seems to fix things
>
> Out of interest does Tonga have GPU reset when things go wrong?
Yes, it does.
Alex
>
> Thanks
>
> Mike
>
> On Tue, 7 Sept 2021 at 15:20, Harry Wentland <harry.wentland@amd.com> wrote:
> >
> >
> >
> > On 2021-09-07 10:10 a.m., Nicholas Kazlauskas wrote:
> > > [Why]
> > > If we're running a headless config with 0 links then the vblank
> > > workqueue will be NULL - causing a NULL pointer exception during
> > > any commit.
> > >
> > > [How]
> > > Guard access to the workqueue if it's NULL and don't queue or flush
> > > work if it is.
> > >
> > > Cc: Roman Li <Roman.Li@amd.com>
> > > Cc: Wayne Lin <Wayne.Lin@amd.com>
> > > Cc: Harry Wentland <Harry.Wentland@amd.com>
> > > Reported-by: Mike Lothian <mike@fireburn.co.uk>
> > > BugLink: https://gitlab.freedesktop.org/drm/amd/-/issues/1700
> > > Fixes: 91f86d4cce2 ("drm/amd/display: Use vblank control events for PSR enable/disable")
> > > Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
> >
> > Reviewed-by: Harry Wentland <harry.wentland@amd.com>
> >
> > Harry
> >
> > > ---
> > > .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 32 +++++++++++--------
> > > 1 file changed, 18 insertions(+), 14 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 8837259215d..46e08736f94 100644
> > > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> > > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> > > @@ -6185,21 +6185,23 @@ static inline int dm_set_vblank(struct drm_crtc *crtc, bool enable)
> > > return 0;
> > >
> > > #if defined(CONFIG_DRM_AMD_DC_DCN)
> > > - work = kzalloc(sizeof(*work), GFP_ATOMIC);
> > > - if (!work)
> > > - return -ENOMEM;
> > > + if (dm->vblank_control_workqueue) {
> > > + work = kzalloc(sizeof(*work), GFP_ATOMIC);
> > > + if (!work)
> > > + return -ENOMEM;
> > >
> > > - INIT_WORK(&work->work, vblank_control_worker);
> > > - work->dm = dm;
> > > - work->acrtc = acrtc;
> > > - work->enable = enable;
> > > + INIT_WORK(&work->work, vblank_control_worker);
> > > + work->dm = dm;
> > > + work->acrtc = acrtc;
> > > + work->enable = enable;
> > >
> > > - if (acrtc_state->stream) {
> > > - dc_stream_retain(acrtc_state->stream);
> > > - work->stream = acrtc_state->stream;
> > > - }
> > > + if (acrtc_state->stream) {
> > > + dc_stream_retain(acrtc_state->stream);
> > > + work->stream = acrtc_state->stream;
> > > + }
> > >
> > > - queue_work(dm->vblank_control_workqueue, &work->work);
> > > + queue_work(dm->vblank_control_workqueue, &work->work);
> > > + }
> > > #endif
> > >
> > > return 0;
> > > @@ -8809,7 +8811,8 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
> > > * If PSR or idle optimizations are enabled then flush out
> > > * any pending work before hardware programming.
> > > */
> > > - flush_workqueue(dm->vblank_control_workqueue);
> > > + if (dm->vblank_control_workqueue)
> > > + flush_workqueue(dm->vblank_control_workqueue);
> > > #endif
> > >
> > > bundle->stream_update.stream = acrtc_state->stream;
> > > @@ -9144,7 +9147,8 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state)
> > > /* if there mode set or reset, disable eDP PSR */
> > > if (mode_set_reset_required) {
> > > #if defined(CONFIG_DRM_AMD_DC_DCN)
> > > - flush_workqueue(dm->vblank_control_workqueue);
> > > + if (dm->vblank_control_workqueue)
> > > + flush_workqueue(dm->vblank_control_workqueue);
> > > #endif
> > > amdgpu_dm_psr_disable_all(dm);
> > > }
> > >
> >
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2021-09-13 18:57 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-09-07 14:10 [PATCH] drm/amd/display: Add NULL checks for vblank workqueue Nicholas Kazlauskas
2021-09-07 14:20 ` Harry Wentland
2021-09-08 1:41 ` Mike Lothian
2021-09-09 19:16 ` Harry Wentland
2021-09-13 18:57 ` Alex Deucher
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