When remoteproc recovery is disabled and rproc crashed, user space
client has no way to reboot co-processor except by a complete platform
reboot.
Indeed rproc_shutdown() is called by sysfs state_store() only is rproc
state is RPROC_RUNNING.
This patch offers the possibility to shutdown the co-processor if
it is in RPROC_CRASHED state and so to restart properly co-processor
from sysfs interface.
Signed-off-by: Loic Pallardy <[email protected]>
---
drivers/remoteproc/remoteproc_core.c | 2 +-
drivers/remoteproc/remoteproc_sysfs.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 097f33e4f1f3..7ac87a75cd1b 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -1812,7 +1812,7 @@ void rproc_shutdown(struct rproc *rproc)
if (!atomic_dec_and_test(&rproc->power))
goto out;
- ret = rproc_stop(rproc, false);
+ ret = rproc_stop(rproc, rproc->state == RPROC_CRASHED);
if (ret) {
atomic_inc(&rproc->power);
goto out;
diff --git a/drivers/remoteproc/remoteproc_sysfs.c b/drivers/remoteproc/remoteproc_sysfs.c
index 7f8536b73295..1029458a4678 100644
--- a/drivers/remoteproc/remoteproc_sysfs.c
+++ b/drivers/remoteproc/remoteproc_sysfs.c
@@ -101,7 +101,7 @@ static ssize_t state_store(struct device *dev,
if (ret)
dev_err(&rproc->dev, "Boot failed: %d\n", ret);
} else if (sysfs_streq(buf, "stop")) {
- if (rproc->state != RPROC_RUNNING)
+ if (rproc->state != RPROC_RUNNING && rproc->state != RPROC_CRASHED)
return -EINVAL;
rproc_shutdown(rproc);
--
2.7.4
Hi Loic,
On Wed, Mar 11, 2020 at 11:54:31AM +0100, Loic Pallardy wrote:
> When remoteproc recovery is disabled and rproc crashed, user space
> client has no way to reboot co-processor except by a complete platform
> reboot.
> Indeed rproc_shutdown() is called by sysfs state_store() only is rproc
> state is RPROC_RUNNING.
>
> This patch offers the possibility to shutdown the co-processor if
> it is in RPROC_CRASHED state and so to restart properly co-processor
> from sysfs interface.
And it is not possible to use the debugfs interface [1] to restart the MCU?
[1]. https://elixir.bootlin.com/linux/v5.6-rc2/source/drivers/remoteproc/remoteproc_debugfs.c#L147
>
> Signed-off-by: Loic Pallardy <[email protected]>
> ---
> drivers/remoteproc/remoteproc_core.c | 2 +-
> drivers/remoteproc/remoteproc_sysfs.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index 097f33e4f1f3..7ac87a75cd1b 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -1812,7 +1812,7 @@ void rproc_shutdown(struct rproc *rproc)
> if (!atomic_dec_and_test(&rproc->power))
> goto out;
>
> - ret = rproc_stop(rproc, false);
> + ret = rproc_stop(rproc, rproc->state == RPROC_CRASHED);
> if (ret) {
> atomic_inc(&rproc->power);
> goto out;
> diff --git a/drivers/remoteproc/remoteproc_sysfs.c b/drivers/remoteproc/remoteproc_sysfs.c
> index 7f8536b73295..1029458a4678 100644
> --- a/drivers/remoteproc/remoteproc_sysfs.c
> +++ b/drivers/remoteproc/remoteproc_sysfs.c
> @@ -101,7 +101,7 @@ static ssize_t state_store(struct device *dev,
> if (ret)
> dev_err(&rproc->dev, "Boot failed: %d\n", ret);
> } else if (sysfs_streq(buf, "stop")) {
> - if (rproc->state != RPROC_RUNNING)
> + if (rproc->state != RPROC_RUNNING && rproc->state != RPROC_CRASHED)
> return -EINVAL;
>
> rproc_shutdown(rproc);
> --
> 2.7.4
>
On Wed 11 Mar 03:54 PDT 2020, Loic Pallardy wrote:
> When remoteproc recovery is disabled and rproc crashed, user space
> client has no way to reboot co-processor except by a complete platform
> reboot.
> Indeed rproc_shutdown() is called by sysfs state_store() only is rproc
> state is RPROC_RUNNING.
>
> This patch offers the possibility to shutdown the co-processor if
> it is in RPROC_CRASHED state and so to restart properly co-processor
> from sysfs interface.
>
I did recently run into a similar problem when I fed my remoteproc
faulty firmware, which lead to it recovering immediately upon boot. The
amount of time spent in !CRASHED state was minimal, so I didn't have any
way to stop the remoteproc.
> Signed-off-by: Loic Pallardy <[email protected]>
> ---
> drivers/remoteproc/remoteproc_core.c | 2 +-
> drivers/remoteproc/remoteproc_sysfs.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index 097f33e4f1f3..7ac87a75cd1b 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -1812,7 +1812,7 @@ void rproc_shutdown(struct rproc *rproc)
> if (!atomic_dec_and_test(&rproc->power))
> goto out;
>
> - ret = rproc_stop(rproc, false);
> + ret = rproc_stop(rproc, rproc->state == RPROC_CRASHED);
Afaict this is unrelated to the problem you're describing in the commit
message.
> if (ret) {
> atomic_inc(&rproc->power);
> goto out;
> diff --git a/drivers/remoteproc/remoteproc_sysfs.c b/drivers/remoteproc/remoteproc_sysfs.c
> index 7f8536b73295..1029458a4678 100644
> --- a/drivers/remoteproc/remoteproc_sysfs.c
> +++ b/drivers/remoteproc/remoteproc_sysfs.c
> @@ -101,7 +101,7 @@ static ssize_t state_store(struct device *dev,
> if (ret)
> dev_err(&rproc->dev, "Boot failed: %d\n", ret);
> } else if (sysfs_streq(buf, "stop")) {
> - if (rproc->state != RPROC_RUNNING)
> + if (rproc->state != RPROC_RUNNING && rproc->state != RPROC_CRASHED)
Analogous to the problem reported by Alex here
https://patchwork.kernel.org/patch/11413161/ the handling of stop seems
racy.
In particular, I believe you're failing to protect against a race
with a just scheduled rproc_crash_handler_work() being executed after
the mutex_unlock() in rproc_shutdown()...
With Alex fix that should be less of a problem though...
Regards,
Bjorn
> return -EINVAL;
>
> rproc_shutdown(rproc);
> --
> 2.7.4
>
Hi Mathieu,
> -----Original Message-----
> From: Mathieu Poirier <[email protected]>
> Sent: mercredi 11 mars 2020 22:45
> To: Loic PALLARDY <[email protected]>
> Cc: [email protected]; [email protected]; linux-
> [email protected]; [email protected]; Arnaud
> POULIQUEN <[email protected]>; [email protected];
> Fabien DESSENNE <[email protected]>; [email protected]
> Subject: Re: [RFC 1/2] remoteproc: sysfs: authorize rproc shutdown when
> rproc is crashed
>
> Hi Loic,
>
> On Wed, Mar 11, 2020 at 11:54:31AM +0100, Loic Pallardy wrote:
> > When remoteproc recovery is disabled and rproc crashed, user space
> > client has no way to reboot co-processor except by a complete platform
> > reboot.
> > Indeed rproc_shutdown() is called by sysfs state_store() only is rproc
> > state is RPROC_RUNNING.
> >
> > This patch offers the possibility to shutdown the co-processor if
> > it is in RPROC_CRASHED state and so to restart properly co-processor
> > from sysfs interface.
>
> And it is not possible to use the debugfs interface [1] to restart the MCU?
>
> [1]. https://elixir.bootlin.com/linux/v5.6-
> rc2/source/drivers/remoteproc/remoteproc_debugfs.c#L147
Debugfs interface is optional and on final product it is often disabled.
The used control interfaces are in kernel API and sysfs one.
Regards,
Loic
>
>
> >
> > Signed-off-by: Loic Pallardy <[email protected]>
> > ---
> > drivers/remoteproc/remoteproc_core.c | 2 +-
> > drivers/remoteproc/remoteproc_sysfs.c | 2 +-
> > 2 files changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/remoteproc/remoteproc_core.c
> b/drivers/remoteproc/remoteproc_core.c
> > index 097f33e4f1f3..7ac87a75cd1b 100644
> > --- a/drivers/remoteproc/remoteproc_core.c
> > +++ b/drivers/remoteproc/remoteproc_core.c
> > @@ -1812,7 +1812,7 @@ void rproc_shutdown(struct rproc *rproc)
> > if (!atomic_dec_and_test(&rproc->power))
> > goto out;
> >
> > - ret = rproc_stop(rproc, false);
> > + ret = rproc_stop(rproc, rproc->state == RPROC_CRASHED);
> > if (ret) {
> > atomic_inc(&rproc->power);
> > goto out;
> > diff --git a/drivers/remoteproc/remoteproc_sysfs.c
> b/drivers/remoteproc/remoteproc_sysfs.c
> > index 7f8536b73295..1029458a4678 100644
> > --- a/drivers/remoteproc/remoteproc_sysfs.c
> > +++ b/drivers/remoteproc/remoteproc_sysfs.c
> > @@ -101,7 +101,7 @@ static ssize_t state_store(struct device *dev,
> > if (ret)
> > dev_err(&rproc->dev, "Boot failed: %d\n", ret);
> > } else if (sysfs_streq(buf, "stop")) {
> > - if (rproc->state != RPROC_RUNNING)
> > + if (rproc->state != RPROC_RUNNING && rproc->state !=
> RPROC_CRASHED)
> > return -EINVAL;
> >
> > rproc_shutdown(rproc);
> > --
> > 2.7.4
> >
Hi Bjorn,
> -----Original Message-----
> From: Bjorn Andersson <[email protected]>
> Sent: jeudi 12 mars 2020 00:27
> To: Loic PALLARDY <[email protected]>
> Cc: [email protected]; [email protected]; linux-
> [email protected]; [email protected]; Arnaud
> POULIQUEN <[email protected]>; [email protected];
> Fabien DESSENNE <[email protected]>; [email protected]
> Subject: Re: [RFC 1/2] remoteproc: sysfs: authorize rproc shutdown when
> rproc is crashed
>
> On Wed 11 Mar 03:54 PDT 2020, Loic Pallardy wrote:
>
> > When remoteproc recovery is disabled and rproc crashed, user space
> > client has no way to reboot co-processor except by a complete platform
> > reboot.
> > Indeed rproc_shutdown() is called by sysfs state_store() only is rproc
> > state is RPROC_RUNNING.
> >
> > This patch offers the possibility to shutdown the co-processor if
> > it is in RPROC_CRASHED state and so to restart properly co-processor
> > from sysfs interface.
> >
>
> I did recently run into a similar problem when I fed my remoteproc
> faulty firmware, which lead to it recovering immediately upon boot. The
> amount of time spent in !CRASHED state was minimal, so I didn't have any
> way to stop the remoteproc.
>
> > Signed-off-by: Loic Pallardy <[email protected]>
> > ---
> > drivers/remoteproc/remoteproc_core.c | 2 +-
> > drivers/remoteproc/remoteproc_sysfs.c | 2 +-
> > 2 files changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/remoteproc/remoteproc_core.c
> b/drivers/remoteproc/remoteproc_core.c
> > index 097f33e4f1f3..7ac87a75cd1b 100644
> > --- a/drivers/remoteproc/remoteproc_core.c
> > +++ b/drivers/remoteproc/remoteproc_core.c
> > @@ -1812,7 +1812,7 @@ void rproc_shutdown(struct rproc *rproc)
> > if (!atomic_dec_and_test(&rproc->power))
> > goto out;
> >
> > - ret = rproc_stop(rproc, false);
> > + ret = rproc_stop(rproc, rproc->state == RPROC_CRASHED);
>
> Afaict this is unrelated to the problem you're describing in the commit
> message.
Right, it is because now rproc_shudown could be could in a context where rproc is in RPROC_CRASHED state and so false is no more the default value.
Could be split in another patch.
>
> > if (ret) {
> > atomic_inc(&rproc->power);
> > goto out;
> > diff --git a/drivers/remoteproc/remoteproc_sysfs.c
> b/drivers/remoteproc/remoteproc_sysfs.c
> > index 7f8536b73295..1029458a4678 100644
> > --- a/drivers/remoteproc/remoteproc_sysfs.c
> > +++ b/drivers/remoteproc/remoteproc_sysfs.c
> > @@ -101,7 +101,7 @@ static ssize_t state_store(struct device *dev,
> > if (ret)
> > dev_err(&rproc->dev, "Boot failed: %d\n", ret);
> > } else if (sysfs_streq(buf, "stop")) {
> > - if (rproc->state != RPROC_RUNNING)
> > + if (rproc->state != RPROC_RUNNING && rproc->state !=
> RPROC_CRASHED)
>
> Analogous to the problem reported by Alex here
> https://patchwork.kernel.org/patch/11413161/ the handling of stop seems
> racy.
>
> In particular, I believe you're failing to protect against a race
> with a just scheduled rproc_crash_handler_work() being executed after
> the mutex_unlock() in rproc_shutdown()...
>
> With Alex fix that should be less of a problem though...
Thanks for pointing me Alex's patch. But I don't think it is exactly the same issue as it concerns the recovery procedure itself.
In my case, the recovery is disabled. On a crash detection, rproc->state is simply set to RPROC_CRASHED
and recovery is not triggered.
Without client action, rproc will stay forever in RPROC_CRASHED test.
Today without this modification, it is not possible to shutdown rproc properly, putting coprocessor under reset, disabling clocks...
Regards,
Loic
>
> Regards,
> Bjorn
>
> > return -EINVAL;
> >
> > rproc_shutdown(rproc);
> > --
> > 2.7.4
> >
Hi Loic,
On Wed, Mar 11, 2020 at 11:54:31AM +0100, Loic Pallardy wrote:
> When remoteproc recovery is disabled and rproc crashed, user space
> client has no way to reboot co-processor except by a complete platform
> reboot.
> Indeed rproc_shutdown() is called by sysfs state_store() only is rproc
> state is RPROC_RUNNING.
>
> This patch offers the possibility to shutdown the co-processor if
> it is in RPROC_CRASHED state and so to restart properly co-processor
> from sysfs interface.
If recovery is disabled on an rproc the platform likely intended to have a hard
reboot and as such we should not be concerned about this case.
Where I think we have a problem, something that is asserted by looking at your 2
patches, is cases where rproc_trigger_recovery() fails. That leaves the system
in a state where it can't be recovered, something the remoteproc core should not
allow.
>
> Signed-off-by: Loic Pallardy <[email protected]>
> ---
> drivers/remoteproc/remoteproc_core.c | 2 +-
> drivers/remoteproc/remoteproc_sysfs.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index 097f33e4f1f3..7ac87a75cd1b 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -1812,7 +1812,7 @@ void rproc_shutdown(struct rproc *rproc)
> if (!atomic_dec_and_test(&rproc->power))
> goto out;
>
> - ret = rproc_stop(rproc, false);
> + ret = rproc_stop(rproc, rproc->state == RPROC_CRASHED);
Please add a comment that explains how we can be in rproc_shutdown() when the
processor has crashed and point to rproc_trigger_recovery(). See below for more
details.
> if (ret) {
> atomic_inc(&rproc->power);
> goto out;
> diff --git a/drivers/remoteproc/remoteproc_sysfs.c b/drivers/remoteproc/remoteproc_sysfs.c
> index 7f8536b73295..1029458a4678 100644
> --- a/drivers/remoteproc/remoteproc_sysfs.c
> +++ b/drivers/remoteproc/remoteproc_sysfs.c
> @@ -101,7 +101,7 @@ static ssize_t state_store(struct device *dev,
> if (ret)
> dev_err(&rproc->dev, "Boot failed: %d\n", ret);
> } else if (sysfs_streq(buf, "stop")) {
> - if (rproc->state != RPROC_RUNNING)
> + if (rproc->state != RPROC_RUNNING && rproc->state != RPROC_CRASHED)
> return -EINVAL;
Wouldn't it be better to just prevent the MCU to stay in a crashed state (when
recovery is not disabled)?
I like what you did in the next patch where the state of the MCU is set to
RPROC_CRASHED in case of failure, so that we keep. I also think the hunk
above is correct. All that is left is to call rproc_shutdown() directly in
rproc_trigger_recovery() when something goes wrong. I would also add a
dev_err() so that users have a clue of what happened.
That would leave the system in a stable state without having to add intelligence
to state_store().
Let me know that you think...
Mathieu
>
> rproc_shutdown(rproc);
> --
> 2.7.4
>
Hi Mathieu,
> -----Original Message-----
> From: Mathieu Poirier <[email protected]>
> Sent: mercredi 25 mars 2020 18:58
> To: Loic PALLARDY <[email protected]>
> Cc: [email protected]; [email protected]; linux-
> [email protected]; [email protected]; Arnaud
> POULIQUEN <[email protected]>; [email protected];
> Fabien DESSENNE <[email protected]>; [email protected]
> Subject: Re: [RFC 1/2] remoteproc: sysfs: authorize rproc shutdown when
> rproc is crashed
>
> Hi Loic,
>
> On Wed, Mar 11, 2020 at 11:54:31AM +0100, Loic Pallardy wrote:
> > When remoteproc recovery is disabled and rproc crashed, user space
> > client has no way to reboot co-processor except by a complete platform
> > reboot.
> > Indeed rproc_shutdown() is called by sysfs state_store() only is rproc
> > state is RPROC_RUNNING.
> >
> > This patch offers the possibility to shutdown the co-processor if
> > it is in RPROC_CRASHED state and so to restart properly co-processor
> > from sysfs interface.
>
> If recovery is disabled on an rproc the platform likely intended to have a hard
> reboot and as such we should not be concerned about this case.
I disagree with your view. In fact, we can have a configuration for which
we don't want a silent recovery. Application layer can be involved to stop and
restart some services because it is the simplest way to resync with the coprocessor.
What's missing today is an event to notify user space application that coprocessor state
has changed. (even if we can rely on rpmsg services closure)
>
> Where I think we have a problem, something that is asserted by looking at
> your 2
> patches, is cases where rproc_trigger_recovery() fails. That leaves the
> system
> in a state where it can't be recovered, something the remoteproc core
> should not
> allow.
>
Right this is a second use case we faced when user space application which provided
firmware file crashed before coprocessor. In that case firmware file may be removed
from /lib/firmware directory and coprocessor recovery failed.
Application, when restarting, can't anymore control coprocessor.
Regards,
Loic
> >
> > Signed-off-by: Loic Pallardy <[email protected]>
> > ---
> > drivers/remoteproc/remoteproc_core.c | 2 +-
> > drivers/remoteproc/remoteproc_sysfs.c | 2 +-
> > 2 files changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/remoteproc/remoteproc_core.c
> b/drivers/remoteproc/remoteproc_core.c
> > index 097f33e4f1f3..7ac87a75cd1b 100644
> > --- a/drivers/remoteproc/remoteproc_core.c
> > +++ b/drivers/remoteproc/remoteproc_core.c
> > @@ -1812,7 +1812,7 @@ void rproc_shutdown(struct rproc *rproc)
> > if (!atomic_dec_and_test(&rproc->power))
> > goto out;
> >
> > - ret = rproc_stop(rproc, false);
> > + ret = rproc_stop(rproc, rproc->state == RPROC_CRASHED);
>
> Please add a comment that explains how we can be in rproc_shutdown()
> when the
> processor has crashed and point to rproc_trigger_recovery(). See below for
> more
> details.
>
> > if (ret) {
> > atomic_inc(&rproc->power);
> > goto out;
> > diff --git a/drivers/remoteproc/remoteproc_sysfs.c
> b/drivers/remoteproc/remoteproc_sysfs.c
> > index 7f8536b73295..1029458a4678 100644
> > --- a/drivers/remoteproc/remoteproc_sysfs.c
> > +++ b/drivers/remoteproc/remoteproc_sysfs.c
> > @@ -101,7 +101,7 @@ static ssize_t state_store(struct device *dev,
> > if (ret)
> > dev_err(&rproc->dev, "Boot failed: %d\n", ret);
> > } else if (sysfs_streq(buf, "stop")) {
> > - if (rproc->state != RPROC_RUNNING)
> > + if (rproc->state != RPROC_RUNNING && rproc->state !=
> RPROC_CRASHED)
> > return -EINVAL;
>
> Wouldn't it be better to just prevent the MCU to stay in a crashed state
> (when
> recovery is not disabled)?
>
> I like what you did in the next patch where the state of the MCU is set to
> RPROC_CRASHED in case of failure, so that we keep. I also think the hunk
> above is correct. All that is left is to call rproc_shutdown() directly in
> rproc_trigger_recovery() when something goes wrong. I would also add a
> dev_err() so that users have a clue of what happened.
>
> That would leave the system in a stable state without having to add
> intelligence
> to state_store().
It is a solution we debate internally. Should rproc_shutdown() called directly in
rproc_trigger_recovery() or not? If we go in such direction, that clearly simplify
coprocessor control as it will always be in a "stable" state. But that means user
will lost information that coprocessor crashed (mainly when recovery is disabled).
We just know that coprocessor is stopped but not why? Crashed or client action?
For debug purpose, it could be an issue from my pov.
Regards,
Loic
>
> Let me know that you think...
>
> Mathieu
>
> >
> > rproc_shutdown(rproc);
> > --
> > 2.7.4
> >
On Wed, 25 Mar 2020 at 12:30, Loic PALLARDY <[email protected]> wrote:
>
> Hi Mathieu,
>
> > -----Original Message-----
> > From: Mathieu Poirier <[email protected]>
> > Sent: mercredi 25 mars 2020 18:58
> > To: Loic PALLARDY <[email protected]>
> > Cc: [email protected]; [email protected]; linux-
> > [email protected]; [email protected]; Arnaud
> > POULIQUEN <[email protected]>; [email protected];
> > Fabien DESSENNE <[email protected]>; [email protected]
> > Subject: Re: [RFC 1/2] remoteproc: sysfs: authorize rproc shutdown when
> > rproc is crashed
> >
> > Hi Loic,
> >
> > On Wed, Mar 11, 2020 at 11:54:31AM +0100, Loic Pallardy wrote:
> > > When remoteproc recovery is disabled and rproc crashed, user space
> > > client has no way to reboot co-processor except by a complete platform
> > > reboot.
> > > Indeed rproc_shutdown() is called by sysfs state_store() only is rproc
> > > state is RPROC_RUNNING.
> > >
> > > This patch offers the possibility to shutdown the co-processor if
> > > it is in RPROC_CRASHED state and so to restart properly co-processor
> > > from sysfs interface.
> >
> > If recovery is disabled on an rproc the platform likely intended to have a hard
> > reboot and as such we should not be concerned about this case.
> I disagree with your view. In fact, we can have a configuration for which
> we don't want a silent recovery. Application layer can be involved to stop and
> restart some services because it is the simplest way to resync with the coprocessor.
> What's missing today is an event to notify user space application that coprocessor state
> has changed. (even if we can rely on rpmsg services closure)
I have a better understanding of the scenario now.
>
> >
> > Where I think we have a problem, something that is asserted by looking at
> > your 2
> > patches, is cases where rproc_trigger_recovery() fails. That leaves the
> > system
> > in a state where it can't be recovered, something the remoteproc core
> > should not
> > allow.
> >
> Right this is a second use case we faced when user space application which provided
> firmware file crashed before coprocessor. In that case firmware file may be removed
> from /lib/firmware directory and coprocessor recovery failed.
> Application, when restarting, can't anymore control coprocessor.
This is a very specific use case. It seems to me that fixing the
problem with the availability of files under /lib/firmware is where
the solution really lies.
>
> Regards,
> Loic
>
> > >
> > > Signed-off-by: Loic Pallardy <[email protected]>
> > > ---
> > > drivers/remoteproc/remoteproc_core.c | 2 +-
> > > drivers/remoteproc/remoteproc_sysfs.c | 2 +-
> > > 2 files changed, 2 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/remoteproc/remoteproc_core.c
> > b/drivers/remoteproc/remoteproc_core.c
> > > index 097f33e4f1f3..7ac87a75cd1b 100644
> > > --- a/drivers/remoteproc/remoteproc_core.c
> > > +++ b/drivers/remoteproc/remoteproc_core.c
> > > @@ -1812,7 +1812,7 @@ void rproc_shutdown(struct rproc *rproc)
> > > if (!atomic_dec_and_test(&rproc->power))
> > > goto out;
> > >
> > > - ret = rproc_stop(rproc, false);
> > > + ret = rproc_stop(rproc, rproc->state == RPROC_CRASHED);
> >
> > Please add a comment that explains how we can be in rproc_shutdown()
> > when the
> > processor has crashed and point to rproc_trigger_recovery(). See below for
> > more
> > details.
> >
> > > if (ret) {
> > > atomic_inc(&rproc->power);
> > > goto out;
> > > diff --git a/drivers/remoteproc/remoteproc_sysfs.c
> > b/drivers/remoteproc/remoteproc_sysfs.c
> > > index 7f8536b73295..1029458a4678 100644
> > > --- a/drivers/remoteproc/remoteproc_sysfs.c
> > > +++ b/drivers/remoteproc/remoteproc_sysfs.c
> > > @@ -101,7 +101,7 @@ static ssize_t state_store(struct device *dev,
> > > if (ret)
> > > dev_err(&rproc->dev, "Boot failed: %d\n", ret);
> > > } else if (sysfs_streq(buf, "stop")) {
> > > - if (rproc->state != RPROC_RUNNING)
> > > + if (rproc->state != RPROC_RUNNING && rproc->state !=
> > RPROC_CRASHED)
> > > return -EINVAL;
> >
> > Wouldn't it be better to just prevent the MCU to stay in a crashed state
> > (when
> > recovery is not disabled)?
> >
> > I like what you did in the next patch where the state of the MCU is set to
> > RPROC_CRASHED in case of failure, so that we keep. I also think the hunk
> > above is correct. All that is left is to call rproc_shutdown() directly in
> > rproc_trigger_recovery() when something goes wrong. I would also add a
> > dev_err() so that users have a clue of what happened.
> >
> > That would leave the system in a stable state without having to add
> > intelligence
> > to state_store().
> It is a solution we debate internally. Should rproc_shutdown() called directly in
> rproc_trigger_recovery() or not? If we go in such direction, that clearly simplify
> coprocessor control as it will always be in a "stable" state. But that means user
> will lost information that coprocessor crashed (mainly when recovery is disabled).
> We just know that coprocessor is stopped but not why? Crashed or client action?
> For debug purpose, it could be an issue from my pov.
That is why I suggested to add a dev_err() so that users know recovery
of the MCU has failed. Moreover I expect users to be aware of what is
happening on their platform, i.e if application did not switch off the
MCU and it is in the offline state, then it is fair to assume it
crashed.
>
> Regards,
> Loic
> >
> > Let me know that you think...
> >
> > Mathieu
> >
> > >
> > > rproc_shutdown(rproc);
> > > --
> > > 2.7.4
> > >