* [PATCH] coresight: Fix crash when Perf and sysfs modes are used concurrently
@ 2023-10-06 13:14 ` James Clark
0 siblings, 0 replies; 8+ messages in thread
From: James Clark @ 2023-10-06 13:14 UTC (permalink / raw)
To: coresight, hejunhao3, suzuki.poulose
Cc: James Clark, Mike Leach, Leo Yan, Alexander Shishkin,
linux-arm-kernel, linux-kernel
Partially revert the change in commit 6148652807ba ("coresight: Enable
and disable helper devices adjacent to the path") which changed the bare
call from source_ops(csdev)->enable() to coresight_enable_source() for
Perf sessions. It was missed that coresight_enable_source() is
specifically for the sysfs interface, rather than being a generic call.
This interferes with the sysfs reference counting to cause the following
crash:
$ perf record -e cs_etm/@tmc_etr0/ -C 0 &
$ echo 1 > /sys/bus/coresight/devices/tmc_etr0/enable_sink
$ echo 1 > /sys/bus/coresight/devices/etm0/enable_source
$ echo 0 > /sys/bus/coresight/devices/etm0/enable_source
Unable to handle kernel NULL pointer dereference at virtual
address 00000000000001d0
Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
...
Call trace:
etm4_disable+0x54/0x150 [coresight_etm4x]
coresight_disable_source+0x6c/0x98 [coresight]
coresight_disable+0x74/0x1c0 [coresight]
enable_source_store+0x88/0xa0 [coresight]
dev_attr_store+0x20/0x40
sysfs_kf_write+0x4c/0x68
kernfs_fop_write_iter+0x120/0x1b8
vfs_write+0x2dc/0x3b0
ksys_write+0x70/0x108
__arm64_sys_write+0x24/0x38
invoke_syscall+0x50/0x128
el0_svc_common.constprop.0+0x104/0x130
do_el0_svc+0x40/0xb8
el0_svc+0x2c/0xb8
el0t_64_sync_handler+0xc0/0xc8
el0t_64_sync+0x1a4/0x1a8
Code: d53cd042 91002000 b9402a81 b8626800 (f940ead5)
---[ end trace 0000000000000000 ]---
This commit linked below also fixes the issue, but has unlocked updates
to the mode which could potentially race. So until we come up with a
more complete solution that takes all locking and interaction between
both modes into account, just revert back to the old behavior for Perf.
Reported-by: Junhao He <hejunhao3@huawei.com>
Closes: https://lore.kernel.org/linux-arm-kernel/20230921132904.60996-1-hejunhao3@huawei.com/
Fixes: 6148652807ba ("coresight: Enable and disable helper devices adjacent to the path")
Signed-off-by: James Clark <james.clark@arm.com>
---
drivers/hwtracing/coresight/coresight-etm-perf.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 5ca6278baff4..89e8ed214ea4 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -493,7 +493,7 @@ static void etm_event_start(struct perf_event *event, int flags)
goto fail_end_stop;
/* Finally enable the tracer */
- if (coresight_enable_source(csdev, CS_MODE_PERF, event))
+ if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF))
goto fail_disable_path;
/*
@@ -587,7 +587,7 @@ static void etm_event_stop(struct perf_event *event, int mode)
return;
/* stop tracer */
- coresight_disable_source(csdev, event);
+ source_ops(csdev)->disable(csdev, event);
/* tell the core */
event->hw.state = PERF_HES_STOPPED;
--
2.34.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH] coresight: Fix crash when Perf and sysfs modes are used concurrently
@ 2023-10-06 13:14 ` James Clark
0 siblings, 0 replies; 8+ messages in thread
From: James Clark @ 2023-10-06 13:14 UTC (permalink / raw)
To: coresight, hejunhao3, suzuki.poulose
Cc: James Clark, Mike Leach, Leo Yan, Alexander Shishkin,
linux-arm-kernel, linux-kernel
Partially revert the change in commit 6148652807ba ("coresight: Enable
and disable helper devices adjacent to the path") which changed the bare
call from source_ops(csdev)->enable() to coresight_enable_source() for
Perf sessions. It was missed that coresight_enable_source() is
specifically for the sysfs interface, rather than being a generic call.
This interferes with the sysfs reference counting to cause the following
crash:
$ perf record -e cs_etm/@tmc_etr0/ -C 0 &
$ echo 1 > /sys/bus/coresight/devices/tmc_etr0/enable_sink
$ echo 1 > /sys/bus/coresight/devices/etm0/enable_source
$ echo 0 > /sys/bus/coresight/devices/etm0/enable_source
Unable to handle kernel NULL pointer dereference at virtual
address 00000000000001d0
Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
...
Call trace:
etm4_disable+0x54/0x150 [coresight_etm4x]
coresight_disable_source+0x6c/0x98 [coresight]
coresight_disable+0x74/0x1c0 [coresight]
enable_source_store+0x88/0xa0 [coresight]
dev_attr_store+0x20/0x40
sysfs_kf_write+0x4c/0x68
kernfs_fop_write_iter+0x120/0x1b8
vfs_write+0x2dc/0x3b0
ksys_write+0x70/0x108
__arm64_sys_write+0x24/0x38
invoke_syscall+0x50/0x128
el0_svc_common.constprop.0+0x104/0x130
do_el0_svc+0x40/0xb8
el0_svc+0x2c/0xb8
el0t_64_sync_handler+0xc0/0xc8
el0t_64_sync+0x1a4/0x1a8
Code: d53cd042 91002000 b9402a81 b8626800 (f940ead5)
---[ end trace 0000000000000000 ]---
This commit linked below also fixes the issue, but has unlocked updates
to the mode which could potentially race. So until we come up with a
more complete solution that takes all locking and interaction between
both modes into account, just revert back to the old behavior for Perf.
Reported-by: Junhao He <hejunhao3@huawei.com>
Closes: https://lore.kernel.org/linux-arm-kernel/20230921132904.60996-1-hejunhao3@huawei.com/
Fixes: 6148652807ba ("coresight: Enable and disable helper devices adjacent to the path")
Signed-off-by: James Clark <james.clark@arm.com>
---
drivers/hwtracing/coresight/coresight-etm-perf.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 5ca6278baff4..89e8ed214ea4 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -493,7 +493,7 @@ static void etm_event_start(struct perf_event *event, int flags)
goto fail_end_stop;
/* Finally enable the tracer */
- if (coresight_enable_source(csdev, CS_MODE_PERF, event))
+ if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF))
goto fail_disable_path;
/*
@@ -587,7 +587,7 @@ static void etm_event_stop(struct perf_event *event, int mode)
return;
/* stop tracer */
- coresight_disable_source(csdev, event);
+ source_ops(csdev)->disable(csdev, event);
/* tell the core */
event->hw.state = PERF_HES_STOPPED;
--
2.34.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH] coresight: Fix crash when Perf and sysfs modes are used concurrently
2023-10-06 13:14 ` James Clark
@ 2023-10-09 12:27 ` Suzuki K Poulose
-1 siblings, 0 replies; 8+ messages in thread
From: Suzuki K Poulose @ 2023-10-09 12:27 UTC (permalink / raw)
To: James Clark, coresight, hejunhao3
Cc: Mike Leach, Leo Yan, Alexander Shishkin, linux-arm-kernel, linux-kernel
Junhao He,
Please could you test the patch and let us know if it resolves the
problem for you ?
On 06/10/2023 14:14, James Clark wrote:
> Partially revert the change in commit 6148652807ba ("coresight: Enable
> and disable helper devices adjacent to the path") which changed the bare
> call from source_ops(csdev)->enable() to coresight_enable_source() for
> Perf sessions. It was missed that coresight_enable_source() is
> specifically for the sysfs interface, rather than being a generic call.
> This interferes with the sysfs reference counting to cause the following
> crash:
>
> $ perf record -e cs_etm/@tmc_etr0/ -C 0 &
> $ echo 1 > /sys/bus/coresight/devices/tmc_etr0/enable_sink
> $ echo 1 > /sys/bus/coresight/devices/etm0/enable_source
> $ echo 0 > /sys/bus/coresight/devices/etm0/enable_source
>
> Unable to handle kernel NULL pointer dereference at virtual
> address 00000000000001d0
> Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
> ...
> Call trace:
> etm4_disable+0x54/0x150 [coresight_etm4x]
> coresight_disable_source+0x6c/0x98 [coresight]
> coresight_disable+0x74/0x1c0 [coresight]
> enable_source_store+0x88/0xa0 [coresight]
> dev_attr_store+0x20/0x40
> sysfs_kf_write+0x4c/0x68
> kernfs_fop_write_iter+0x120/0x1b8
> vfs_write+0x2dc/0x3b0
> ksys_write+0x70/0x108
> __arm64_sys_write+0x24/0x38
> invoke_syscall+0x50/0x128
> el0_svc_common.constprop.0+0x104/0x130
> do_el0_svc+0x40/0xb8
> el0_svc+0x2c/0xb8
> el0t_64_sync_handler+0xc0/0xc8
> el0t_64_sync+0x1a4/0x1a8
> Code: d53cd042 91002000 b9402a81 b8626800 (f940ead5)
> ---[ end trace 0000000000000000 ]---
>
> This commit linked below also fixes the issue, but has unlocked updates
> to the mode which could potentially race. So until we come up with a
> more complete solution that takes all locking and interaction between
> both modes into account, just revert back to the old behavior for Perf.
>
> Reported-by: Junhao He <hejunhao3@huawei.com>
> Closes: https://lore.kernel.org/linux-arm-kernel/20230921132904.60996-1-hejunhao3@huawei.com/
> Fixes: 6148652807ba ("coresight: Enable and disable helper devices adjacent to the path")
> Signed-off-by: James Clark <james.clark@arm.com>
The patch looks good to me. I will wait for Junhao to test this before
pulling it in.
Suzuki
> ---
> drivers/hwtracing/coresight/coresight-etm-perf.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
> index 5ca6278baff4..89e8ed214ea4 100644
> --- a/drivers/hwtracing/coresight/coresight-etm-perf.c
> +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
> @@ -493,7 +493,7 @@ static void etm_event_start(struct perf_event *event, int flags)
> goto fail_end_stop;
>
> /* Finally enable the tracer */
> - if (coresight_enable_source(csdev, CS_MODE_PERF, event))
> + if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF))
> goto fail_disable_path;
>
> /*
> @@ -587,7 +587,7 @@ static void etm_event_stop(struct perf_event *event, int mode)
> return;
>
> /* stop tracer */
> - coresight_disable_source(csdev, event);
> + source_ops(csdev)->disable(csdev, event);
>
> /* tell the core */
> event->hw.state = PERF_HES_STOPPED;
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] coresight: Fix crash when Perf and sysfs modes are used concurrently
@ 2023-10-09 12:27 ` Suzuki K Poulose
0 siblings, 0 replies; 8+ messages in thread
From: Suzuki K Poulose @ 2023-10-09 12:27 UTC (permalink / raw)
To: James Clark, coresight, hejunhao3
Cc: Mike Leach, Leo Yan, Alexander Shishkin, linux-arm-kernel, linux-kernel
Junhao He,
Please could you test the patch and let us know if it resolves the
problem for you ?
On 06/10/2023 14:14, James Clark wrote:
> Partially revert the change in commit 6148652807ba ("coresight: Enable
> and disable helper devices adjacent to the path") which changed the bare
> call from source_ops(csdev)->enable() to coresight_enable_source() for
> Perf sessions. It was missed that coresight_enable_source() is
> specifically for the sysfs interface, rather than being a generic call.
> This interferes with the sysfs reference counting to cause the following
> crash:
>
> $ perf record -e cs_etm/@tmc_etr0/ -C 0 &
> $ echo 1 > /sys/bus/coresight/devices/tmc_etr0/enable_sink
> $ echo 1 > /sys/bus/coresight/devices/etm0/enable_source
> $ echo 0 > /sys/bus/coresight/devices/etm0/enable_source
>
> Unable to handle kernel NULL pointer dereference at virtual
> address 00000000000001d0
> Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
> ...
> Call trace:
> etm4_disable+0x54/0x150 [coresight_etm4x]
> coresight_disable_source+0x6c/0x98 [coresight]
> coresight_disable+0x74/0x1c0 [coresight]
> enable_source_store+0x88/0xa0 [coresight]
> dev_attr_store+0x20/0x40
> sysfs_kf_write+0x4c/0x68
> kernfs_fop_write_iter+0x120/0x1b8
> vfs_write+0x2dc/0x3b0
> ksys_write+0x70/0x108
> __arm64_sys_write+0x24/0x38
> invoke_syscall+0x50/0x128
> el0_svc_common.constprop.0+0x104/0x130
> do_el0_svc+0x40/0xb8
> el0_svc+0x2c/0xb8
> el0t_64_sync_handler+0xc0/0xc8
> el0t_64_sync+0x1a4/0x1a8
> Code: d53cd042 91002000 b9402a81 b8626800 (f940ead5)
> ---[ end trace 0000000000000000 ]---
>
> This commit linked below also fixes the issue, but has unlocked updates
> to the mode which could potentially race. So until we come up with a
> more complete solution that takes all locking and interaction between
> both modes into account, just revert back to the old behavior for Perf.
>
> Reported-by: Junhao He <hejunhao3@huawei.com>
> Closes: https://lore.kernel.org/linux-arm-kernel/20230921132904.60996-1-hejunhao3@huawei.com/
> Fixes: 6148652807ba ("coresight: Enable and disable helper devices adjacent to the path")
> Signed-off-by: James Clark <james.clark@arm.com>
The patch looks good to me. I will wait for Junhao to test this before
pulling it in.
Suzuki
> ---
> drivers/hwtracing/coresight/coresight-etm-perf.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
> index 5ca6278baff4..89e8ed214ea4 100644
> --- a/drivers/hwtracing/coresight/coresight-etm-perf.c
> +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
> @@ -493,7 +493,7 @@ static void etm_event_start(struct perf_event *event, int flags)
> goto fail_end_stop;
>
> /* Finally enable the tracer */
> - if (coresight_enable_source(csdev, CS_MODE_PERF, event))
> + if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF))
> goto fail_disable_path;
>
> /*
> @@ -587,7 +587,7 @@ static void etm_event_stop(struct perf_event *event, int mode)
> return;
>
> /* stop tracer */
> - coresight_disable_source(csdev, event);
> + source_ops(csdev)->disable(csdev, event);
>
> /* tell the core */
> event->hw.state = PERF_HES_STOPPED;
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] coresight: Fix crash when Perf and sysfs modes are used concurrently
2023-10-09 12:27 ` Suzuki K Poulose
@ 2023-10-10 2:43 ` hejunhao
-1 siblings, 0 replies; 8+ messages in thread
From: hejunhao @ 2023-10-10 2:43 UTC (permalink / raw)
To: Suzuki K Poulose, James Clark, coresight
Cc: Mike Leach, Alexander Shishkin, linux-arm-kernel, linux-kernel
On 2023/10/9 20:27, Suzuki K Poulose wrote:
> Junhao He,
>
> Please could you test the patch and let us know if it resolves the
> problem for you ?
Hi James and Suzuki ,
I tested the patch on my platform and it worked well.
>
> On 06/10/2023 14:14, James Clark wrote:
>> Partially revert the change in commit 6148652807ba ("coresight: Enable
>> and disable helper devices adjacent to the path") which changed the bare
>> call from source_ops(csdev)->enable() to coresight_enable_source() for
>> Perf sessions. It was missed that coresight_enable_source() is
>> specifically for the sysfs interface, rather than being a generic call.
>> This interferes with the sysfs reference counting to cause the following
>> crash:
>>
>> $ perf record -e cs_etm/@tmc_etr0/ -C 0 &
>> $ echo 1 > /sys/bus/coresight/devices/tmc_etr0/enable_sink
>> $ echo 1 > /sys/bus/coresight/devices/etm0/enable_source
>> $ echo 0 > /sys/bus/coresight/devices/etm0/enable_source
>>
>> Unable to handle kernel NULL pointer dereference at virtual
>> address 00000000000001d0
>> Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
>> ...
>> Call trace:
>> etm4_disable+0x54/0x150 [coresight_etm4x]
>> coresight_disable_source+0x6c/0x98 [coresight]
>> coresight_disable+0x74/0x1c0 [coresight]
>> enable_source_store+0x88/0xa0 [coresight]
>> dev_attr_store+0x20/0x40
>> sysfs_kf_write+0x4c/0x68
>> kernfs_fop_write_iter+0x120/0x1b8
>> vfs_write+0x2dc/0x3b0
>> ksys_write+0x70/0x108
>> __arm64_sys_write+0x24/0x38
>> invoke_syscall+0x50/0x128
>> el0_svc_common.constprop.0+0x104/0x130
>> do_el0_svc+0x40/0xb8
>> el0_svc+0x2c/0xb8
>> el0t_64_sync_handler+0xc0/0xc8
>> el0t_64_sync+0x1a4/0x1a8
>> Code: d53cd042 91002000 b9402a81 b8626800 (f940ead5)
>> ---[ end trace 0000000000000000 ]---
>>
>> This commit linked below also fixes the issue, but has unlocked updates
>> to the mode which could potentially race. So until we come up with a
>> more complete solution that takes all locking and interaction between
>> both modes into account, just revert back to the old behavior for Perf.
>>
>> Reported-by: Junhao He <hejunhao3@huawei.com>
>> Closes:
>> https://lore.kernel.org/linux-arm-kernel/20230921132904.60996-1-hejunhao3@huawei.com/
>> Fixes: 6148652807ba ("coresight: Enable and disable helper devices
>> adjacent to the path")
>> Signed-off-by: James Clark <james.clark@arm.com>
>
> The patch looks good to me. I will wait for Junhao to test this before
> pulling it in.
>
> Suzuki
>
Tested-by: Junhao He <hejunhao3@huawei.com>
Thanks.
Junhao.
>
>
>
>> ---
>> drivers/hwtracing/coresight/coresight-etm-perf.c | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c
>> b/drivers/hwtracing/coresight/coresight-etm-perf.c
>> index 5ca6278baff4..89e8ed214ea4 100644
>> --- a/drivers/hwtracing/coresight/coresight-etm-perf.c
>> +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
>> @@ -493,7 +493,7 @@ static void etm_event_start(struct perf_event
>> *event, int flags)
>> goto fail_end_stop;
>> /* Finally enable the tracer */
>> - if (coresight_enable_source(csdev, CS_MODE_PERF, event))
>> + if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF))
>> goto fail_disable_path;
>> /*
>> @@ -587,7 +587,7 @@ static void etm_event_stop(struct perf_event
>> *event, int mode)
>> return;
>> /* stop tracer */
>> - coresight_disable_source(csdev, event);
>> + source_ops(csdev)->disable(csdev, event);
>> /* tell the core */
>> event->hw.state = PERF_HES_STOPPED;
>
> _______________________________________________
> CoreSight mailing list -- coresight@lists.linaro.org
> To unsubscribe send an email to coresight-leave@lists.linaro.org
>
> .
>
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] coresight: Fix crash when Perf and sysfs modes are used concurrently
@ 2023-10-10 2:43 ` hejunhao
0 siblings, 0 replies; 8+ messages in thread
From: hejunhao @ 2023-10-10 2:43 UTC (permalink / raw)
To: Suzuki K Poulose, James Clark, coresight
Cc: Mike Leach, Alexander Shishkin, linux-arm-kernel, linux-kernel
On 2023/10/9 20:27, Suzuki K Poulose wrote:
> Junhao He,
>
> Please could you test the patch and let us know if it resolves the
> problem for you ?
Hi James and Suzuki ,
I tested the patch on my platform and it worked well.
>
> On 06/10/2023 14:14, James Clark wrote:
>> Partially revert the change in commit 6148652807ba ("coresight: Enable
>> and disable helper devices adjacent to the path") which changed the bare
>> call from source_ops(csdev)->enable() to coresight_enable_source() for
>> Perf sessions. It was missed that coresight_enable_source() is
>> specifically for the sysfs interface, rather than being a generic call.
>> This interferes with the sysfs reference counting to cause the following
>> crash:
>>
>> $ perf record -e cs_etm/@tmc_etr0/ -C 0 &
>> $ echo 1 > /sys/bus/coresight/devices/tmc_etr0/enable_sink
>> $ echo 1 > /sys/bus/coresight/devices/etm0/enable_source
>> $ echo 0 > /sys/bus/coresight/devices/etm0/enable_source
>>
>> Unable to handle kernel NULL pointer dereference at virtual
>> address 00000000000001d0
>> Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
>> ...
>> Call trace:
>> etm4_disable+0x54/0x150 [coresight_etm4x]
>> coresight_disable_source+0x6c/0x98 [coresight]
>> coresight_disable+0x74/0x1c0 [coresight]
>> enable_source_store+0x88/0xa0 [coresight]
>> dev_attr_store+0x20/0x40
>> sysfs_kf_write+0x4c/0x68
>> kernfs_fop_write_iter+0x120/0x1b8
>> vfs_write+0x2dc/0x3b0
>> ksys_write+0x70/0x108
>> __arm64_sys_write+0x24/0x38
>> invoke_syscall+0x50/0x128
>> el0_svc_common.constprop.0+0x104/0x130
>> do_el0_svc+0x40/0xb8
>> el0_svc+0x2c/0xb8
>> el0t_64_sync_handler+0xc0/0xc8
>> el0t_64_sync+0x1a4/0x1a8
>> Code: d53cd042 91002000 b9402a81 b8626800 (f940ead5)
>> ---[ end trace 0000000000000000 ]---
>>
>> This commit linked below also fixes the issue, but has unlocked updates
>> to the mode which could potentially race. So until we come up with a
>> more complete solution that takes all locking and interaction between
>> both modes into account, just revert back to the old behavior for Perf.
>>
>> Reported-by: Junhao He <hejunhao3@huawei.com>
>> Closes:
>> https://lore.kernel.org/linux-arm-kernel/20230921132904.60996-1-hejunhao3@huawei.com/
>> Fixes: 6148652807ba ("coresight: Enable and disable helper devices
>> adjacent to the path")
>> Signed-off-by: James Clark <james.clark@arm.com>
>
> The patch looks good to me. I will wait for Junhao to test this before
> pulling it in.
>
> Suzuki
>
Tested-by: Junhao He <hejunhao3@huawei.com>
Thanks.
Junhao.
>
>
>
>> ---
>> drivers/hwtracing/coresight/coresight-etm-perf.c | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c
>> b/drivers/hwtracing/coresight/coresight-etm-perf.c
>> index 5ca6278baff4..89e8ed214ea4 100644
>> --- a/drivers/hwtracing/coresight/coresight-etm-perf.c
>> +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
>> @@ -493,7 +493,7 @@ static void etm_event_start(struct perf_event
>> *event, int flags)
>> goto fail_end_stop;
>> /* Finally enable the tracer */
>> - if (coresight_enable_source(csdev, CS_MODE_PERF, event))
>> + if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF))
>> goto fail_disable_path;
>> /*
>> @@ -587,7 +587,7 @@ static void etm_event_stop(struct perf_event
>> *event, int mode)
>> return;
>> /* stop tracer */
>> - coresight_disable_source(csdev, event);
>> + source_ops(csdev)->disable(csdev, event);
>> /* tell the core */
>> event->hw.state = PERF_HES_STOPPED;
>
> _______________________________________________
> CoreSight mailing list -- coresight@lists.linaro.org
> To unsubscribe send an email to coresight-leave@lists.linaro.org
>
> .
>
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linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] coresight: Fix crash when Perf and sysfs modes are used concurrently
2023-10-06 13:14 ` James Clark
@ 2023-10-16 23:05 ` Suzuki K Poulose
-1 siblings, 0 replies; 8+ messages in thread
From: Suzuki K Poulose @ 2023-10-16 23:05 UTC (permalink / raw)
To: coresight, James Clark, hejunhao3
Cc: Suzuki K Poulose, Mike Leach, Alexander Shishkin, Leo Yan,
linux-arm-kernel, linux-kernel
On Fri, 6 Oct 2023 14:14:52 +0100, James Clark wrote:
> Partially revert the change in commit 6148652807ba ("coresight: Enable
> and disable helper devices adjacent to the path") which changed the bare
> call from source_ops(csdev)->enable() to coresight_enable_source() for
> Perf sessions. It was missed that coresight_enable_source() is
> specifically for the sysfs interface, rather than being a generic call.
> This interferes with the sysfs reference counting to cause the following
> crash:
>
> [...]
Applied, thanks!
[1/1] coresight: Fix crash when Perf and sysfs modes are used concurrently
https://git.kernel.org/coresight/c/078dbba3f0c9
Best regards,
--
Suzuki K Poulose <suzuki.poulose@arm.com>
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] coresight: Fix crash when Perf and sysfs modes are used concurrently
@ 2023-10-16 23:05 ` Suzuki K Poulose
0 siblings, 0 replies; 8+ messages in thread
From: Suzuki K Poulose @ 2023-10-16 23:05 UTC (permalink / raw)
To: coresight, James Clark, hejunhao3
Cc: Suzuki K Poulose, Mike Leach, Alexander Shishkin, Leo Yan,
linux-arm-kernel, linux-kernel
On Fri, 6 Oct 2023 14:14:52 +0100, James Clark wrote:
> Partially revert the change in commit 6148652807ba ("coresight: Enable
> and disable helper devices adjacent to the path") which changed the bare
> call from source_ops(csdev)->enable() to coresight_enable_source() for
> Perf sessions. It was missed that coresight_enable_source() is
> specifically for the sysfs interface, rather than being a generic call.
> This interferes with the sysfs reference counting to cause the following
> crash:
>
> [...]
Applied, thanks!
[1/1] coresight: Fix crash when Perf and sysfs modes are used concurrently
https://git.kernel.org/coresight/c/078dbba3f0c9
Best regards,
--
Suzuki K Poulose <suzuki.poulose@arm.com>
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2023-10-16 23:06 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-10-06 13:14 [PATCH] coresight: Fix crash when Perf and sysfs modes are used concurrently James Clark
2023-10-06 13:14 ` James Clark
2023-10-09 12:27 ` Suzuki K Poulose
2023-10-09 12:27 ` Suzuki K Poulose
2023-10-10 2:43 ` hejunhao
2023-10-10 2:43 ` hejunhao
2023-10-16 23:05 ` Suzuki K Poulose
2023-10-16 23:05 ` Suzuki K Poulose
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