On 20-08-2024 20:29, Beleswar Prasad Padhi wrote:
On 20-08-2024 19:50, Jan Kiszka wrote:
On 20.08.24 11:48, Beleswar Prasad Padhi wrote:
On 20-08-2024 15:09, Jan Kiszka wrote:
On 20.08.24 11:30, Beleswar Prasad Padhi wrote:
Hi Jan,
On 19-08-2024 22:17, Jan Kiszka wrote:
From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
When k3_r5_cluster_rproc_exit is run, core 1 is shutdown and removed
first. When core 0 should then be stopped before its removal, it
will
find core1->rproc as NULL already and crashes. Happens on rmmod e.g.
Did you check this on top of -next-20240820 tag? There was a
series[0]
which was merged recently which fixed this condition. I don't see
this
issue when trying on top of -next-20240820 tag.
[0]:
https://lore.kernel.org/all/20240808074127.2688131-1-b-padhi@xxxxxx/
I didn't try those yet, I was on 6.11-rcX. But from reading them
quickly, I'm not seeing the two issues I found directly addressed
there.
Check the comment by Andrew Davis[0], that addresses the above issue.
[0]:
https://lore.kernel.org/all/0bba5293-a55d-4f13-887c-272a54d6e1ca@xxxxxx/
OK, then someone still needs to update his patch accordingly.
That comment was addressed in the v4 series revision[1] and was merged
to linux-next, available with tag -next-20240820. Request you to
please check if the issue persists with -next-20240820 tag. I checked
myself, and was not able to reproduce.
[1]: https://lore.kernel.org/all/Zr9nbWnADDB+ZOlg@p14s/
Fixes: 3c8a9066d584 ("remoteproc: k3-r5: Do not allow core1 to power
up before core0 via sysfs")
CC: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
---
There might be one more because I can still make this driver crash
after an operator error. Were error scenarios tested at all?
Can you point out what is this issue more specifically, and I can
take
this up then.
Try starting core1 before core0, and then again - system will hang or
If you are trying to stop and then start the cores from sysfs, that is
not yet supported. The hang is thus expected.
What? Then the driver is broken, even more. Why wasn't it fully
implemented?
Just wanted to point out that this "graceful shutdown" feature is
majorly dependent on the Device Manager Firmware(point 3) and minimal
changes to the remoteproc driver (point 2 and 4). Thus, as soon as
Firmware is capable, we will send out the patches for this feature.
The driver is capable of starting a core and stopping it all well. The
problem is, when we stop a core from sysfs (without resetting the SoC
itself), the remotecore is powered off, but its resources are not
relinquished. So when we start it back, there could be some memory
corruptions. This feature of "graceful shutdown" of remotecores is
almost implemented and will be posted to this driver soon. Request you
to try out after that.
With graceful shutdown feature, this will be the flow:
1. We issue a core stop operation from sysfs.
2. The remoteproc driver sends a special "SHUTDOWN" mailbox message to
the remotecore.
3. The remotecore relinquishes all of its acquired resources through
Device Manager Firmware and sends an ACK back.
4. The remotecore enters WFI state and then is resetted through Host
core.
5. Then, if we try to do the core start operation from sysfs, core
should be up as expected.
Thanks,
Beleswar
Jan
