Karol Herbst
2023-Feb-20 11:26 UTC
[Nouveau] linux-6.2-rc4+ hangs on poweroff/reboot: Bisected
On Mon, Feb 20, 2023 at 11:51 AM Chris Clayton <chris2553 at googlemail.com> wrote:> > > > On 20/02/2023 05:35, Ben Skeggs wrote: > > On Sun, 19 Feb 2023 at 04:55, Chris Clayton <chris2553 at googlemail.com> wrote: > >> > >> > >> > >> On 18/02/2023 15:19, Chris Clayton wrote: > >>> > >>> > >>> On 18/02/2023 12:25, Karol Herbst wrote: > >>>> On Sat, Feb 18, 2023 at 1:22 PM Chris Clayton <chris2553 at googlemail.com> wrote: > >>>>> > >>>>> > >>>>> > >>>>> On 15/02/2023 11:09, Karol Herbst wrote: > >>>>>> On Wed, Feb 15, 2023 at 11:36 AM Linux regression tracking #update > >>>>>> (Thorsten Leemhuis) <regressions at leemhuis.info> wrote: > >>>>>>> > >>>>>>> On 13.02.23 10:14, Chris Clayton wrote: > >>>>>>>> On 13/02/2023 02:57, Dave Airlie wrote: > >>>>>>>>> On Sun, 12 Feb 2023 at 00:43, Chris Clayton <chris2553 at googlemail.com> wrote: > >>>>>>>>>> > >>>>>>>>>> > >>>>>>>>>> > >>>>>>>>>> On 10/02/2023 19:33, Linux regression tracking (Thorsten Leemhuis) wrote: > >>>>>>>>>>> On 10.02.23 20:01, Karol Herbst wrote: > >>>>>>>>>>>> On Fri, Feb 10, 2023 at 7:35 PM Linux regression tracking (Thorsten > >>>>>>>>>>>> Leemhuis) <regressions at leemhuis.info> wrote: > >>>>>>>>>>>>> > >>>>>>>>>>>>> On 08.02.23 09:48, Chris Clayton wrote: > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> I'm assuming that we are not going to see a fix for this regression before 6.2 is released. > >>>>>>>>>>>>> > >>>>>>>>>>>>> Yeah, looks like it. That's unfortunate, but happens. But there is still > >>>>>>>>>>>>> time to fix it and there is one thing I wonder: > >>>>>>>>>>>>> > >>>>>>>>>>>>> Did any of the nouveau developers look at the netconsole captures Chris > >>>>>>>>>>>>> posted more than a week ago to check if they somehow help to track down > >>>>>>>>>>>>> the root of this problem? > >>>>>>>>>>>> > >>>>>>>>>>>> I did now and I can't spot anything. I think at this point it would > >>>>>>>>>>>> make sense to dump the active tasks/threads via sqsrq keys to see if > >>>>>>>>>>>> any is in a weird state preventing the machine from shutting down. > >>>>>>>>>>> > >>>>>>>>>>> Many thx for looking into it! > >>>>>>>>>> > >>>>>>>>>> Yes, thanks Karol. > >>>>>>>>>> > >>>>>>>>>> Attached is the output from dmesg when this block of code: > >>>>>>>>>> > >>>>>>>>>> /bin/mount /dev/sda7 /mnt/sda7 > >>>>>>>>>> /bin/mountpoint /proc || /bin/mount /proc > >>>>>>>>>> /bin/dmesg -w > /mnt/sda7/sysrq.dmesg.log & > >>>>>>>>>> /bin/echo t > /proc/sysrq-trigger > >>>>>>>>>> /bin/sleep 1 > >>>>>>>>>> /bin/sync > >>>>>>>>>> /bin/sleep 1 > >>>>>>>>>> kill $(pidof dmesg) > >>>>>>>>>> /bin/umount /mnt/sda7 > >>>>>>>>>> > >>>>>>>>>> is executed immediately before /sbin/reboot is called as the final step of rebooting my system. > >>>>>>>>>> > >>>>>>>>>> I hope this is what you were looking for, but if not, please let me know what you need > >>>>>>>> > >>>>>>>> Thanks Dave. [...] > >>>>>>> FWIW, in case anyone strands here in the archives: the msg was > >>>>>>> truncated. The full post can be found in a new thread: > >>>>>>> > >>>>>>> https://lore.kernel.org/lkml/e0b80506-b3cf-315b-4327-1b988d86031e at googlemail.com/ > >>>>>>> > >>>>>>> Sadly it seems the info "With runpm=0, both reboot and poweroff work on > >>>>>>> my laptop." didn't bring us much further to a solution. :-/ I don't > >>>>>>> really like it, but for regression tracking I'm now putting this on the > >>>>>>> back-burner, as a fix is not in sight. > >>>>>>> > >>>>>>> #regzbot monitor: > >>>>>>> https://lore.kernel.org/lkml/e0b80506-b3cf-315b-4327-1b988d86031e at googlemail.com/ > >>>>>>> #regzbot backburner: hard to debug and apparently rare > >>>>>>> #regzbot ignore-activity > >>>>>>> > >>>>>> > >>>>>> yeah.. this bug looks a little annoying. Sadly the only Turing based > >>>>>> laptop I got doesn't work on Nouveau because of firmware related > >>>>>> issues and we probably need to get updated ones from Nvidia here :( > >>>>>> > >>>>>> But it's a bit weird that the kernel doesn't shutdown, because I don't > >>>>>> see anything in the logs which would prevent that from happening. > >>>>>> Unless it's waiting on one of the tasks to complete, but none of them > >>>>>> looked in any way nouveau related. > >>>>>> > >>>>>> If somebody else has any fancy kernel debugging tips here to figure > >>>>>> out why it hangs, that would be very helpful... > >>>>>> > >>>>> > >>>>> I think I've figured this out. It's to do with how my system is configured. I do have an initrd, but the only thing on > >>>>> it is the cpu microcode which, it is recommended, should be loaded early. The absence of the NVidia firmare from an > >>>>> initrd doesn't matter because the drivers for the hardware that need to load firmware are all built as modules, So, by > >>>>> the time the devices are configured via udev, the root partition is mounted and the drivers can get at the firmware. > >>>>> > >>>>> I've found, by turning on nouveau debug and taking a video of the screen as the system shuts down, that nouveau seems to > >>>>> be trying to run the scrubber very very late in the shutdown process. The problem is that by this time, I think the root > >>>>> partition, and thus the scrubber binary, have become inaccessible. > >>>>> > >>>>> I seem to have two choices - either make the firmware accessible on an initrd or unload the module in a shutdown script > >>>>> before the scrubber binary becomes inaccessible. The latter of these is the workaround I have implemented whilst the > >>>>> problem I reported has been under investigation. For simplicity, I think I'll promote my workaround to being the > >>>>> permanent solution. > >>>>> > >>>>> So, apologies (and thanks) to everyone whose time I have taken up with this non-bug. > >>>>> > >>>> > >>>> Well.. nouveau shouldn't prevent the system from shutting down if the > >>>> firmware file isn't available. Or at least it should print a > >>>> warning/error. Mind messing with the code a little to see if skipping > >>>> it kind of works? I probably can also come up with a patch by next > >>>> week. > >>>> > >>> Well, I'd love to but a quick glance at the code caused me to bump into this obscenity: > >>> > >>> int > >>> gm200_flcn_reset_wait_mem_scrubbing(struct nvkm_falcon *falcon) > >>> { > >>> nvkm_falcon_mask(falcon, 0x040, 0x00000000, 0x00000000); > >>> > >>> if (nvkm_msec(falcon->owner->device, 10, > >>> if (!(nvkm_falcon_rd32(falcon, 0x10c) & 0x00000006)) > >>> break; > >>> ) < 0) > >>> return -ETIMEDOUT; > >>> > >>> return 0; > >>> } > >>> > >>> nvkm_msec is #defined to nvkm_usec which in turn is #defined to nvkm_nsec where the loop that the break is related to > >>> appears > >> > >> I think someone who knows the code needs to look at this. What I can confirm is that after a freeze, I waited for 90 > >> seconds for a timeout to occur, but it didn't. > > Hey, > > > > Are you able to try the attached patch for me please? > > > > Thanks, > > Ben. > > > > Thanks Ben. > > Yes, this patch fixes the lockup on reboot and poweroff that I've been seeing on my laptop. As you would expect, > offloaded rendering is still working and the discrete GPU is being powered on and off as required. > > Thanks. > > Reported-by: Chris Clayton <chris2553 at googlemail.com> > Tested-by: Chris Clayton <chris2553 at googlemail.com> >Ben, did you manage to get push rights to drm-misc by now or should I just pick the patch and push it through -fixes?> >> > >> > >> .> Chris > >>>>> > >>>>>>> Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) > >>>>>>> -- > >>>>>>> Everything you wanna know about Linux kernel regression tracking: > >>>>>>> https://linux-regtracking.leemhuis.info/about/#tldr > >>>>>>> That page also explains what to do if mails like this annoy you. > >>>>>>> > >>>>>>> #regzbot ignore-activity > >>>>>>> > >>>>>> > >>>>> > >>>> >
Ben Skeggs
2023-Feb-20 22:16 UTC
[Nouveau] linux-6.2-rc4+ hangs on poweroff/reboot: Bisected
On Mon, 20 Feb 2023 at 21:27, Karol Herbst <kherbst at redhat.com> wrote:> > On Mon, Feb 20, 2023 at 11:51 AM Chris Clayton <chris2553 at googlemail.com> wrote: > > > > > > > > On 20/02/2023 05:35, Ben Skeggs wrote: > > > On Sun, 19 Feb 2023 at 04:55, Chris Clayton <chris2553 at googlemail.com> wrote: > > >> > > >> > > >> > > >> On 18/02/2023 15:19, Chris Clayton wrote: > > >>> > > >>> > > >>> On 18/02/2023 12:25, Karol Herbst wrote: > > >>>> On Sat, Feb 18, 2023 at 1:22 PM Chris Clayton <chris2553 at googlemail.com> wrote: > > >>>>> > > >>>>> > > >>>>> > > >>>>> On 15/02/2023 11:09, Karol Herbst wrote: > > >>>>>> On Wed, Feb 15, 2023 at 11:36 AM Linux regression tracking #update > > >>>>>> (Thorsten Leemhuis) <regressions at leemhuis.info> wrote: > > >>>>>>> > > >>>>>>> On 13.02.23 10:14, Chris Clayton wrote: > > >>>>>>>> On 13/02/2023 02:57, Dave Airlie wrote: > > >>>>>>>>> On Sun, 12 Feb 2023 at 00:43, Chris Clayton <chris2553 at googlemail.com> wrote: > > >>>>>>>>>> > > >>>>>>>>>> > > >>>>>>>>>> > > >>>>>>>>>> On 10/02/2023 19:33, Linux regression tracking (Thorsten Leemhuis) wrote: > > >>>>>>>>>>> On 10.02.23 20:01, Karol Herbst wrote: > > >>>>>>>>>>>> On Fri, Feb 10, 2023 at 7:35 PM Linux regression tracking (Thorsten > > >>>>>>>>>>>> Leemhuis) <regressions at leemhuis.info> wrote: > > >>>>>>>>>>>>> > > >>>>>>>>>>>>> On 08.02.23 09:48, Chris Clayton wrote: > > >>>>>>>>>>>>>> > > >>>>>>>>>>>>>> I'm assuming that we are not going to see a fix for this regression before 6.2 is released. > > >>>>>>>>>>>>> > > >>>>>>>>>>>>> Yeah, looks like it. That's unfortunate, but happens. But there is still > > >>>>>>>>>>>>> time to fix it and there is one thing I wonder: > > >>>>>>>>>>>>> > > >>>>>>>>>>>>> Did any of the nouveau developers look at the netconsole captures Chris > > >>>>>>>>>>>>> posted more than a week ago to check if they somehow help to track down > > >>>>>>>>>>>>> the root of this problem? > > >>>>>>>>>>>> > > >>>>>>>>>>>> I did now and I can't spot anything. I think at this point it would > > >>>>>>>>>>>> make sense to dump the active tasks/threads via sqsrq keys to see if > > >>>>>>>>>>>> any is in a weird state preventing the machine from shutting down. > > >>>>>>>>>>> > > >>>>>>>>>>> Many thx for looking into it! > > >>>>>>>>>> > > >>>>>>>>>> Yes, thanks Karol. > > >>>>>>>>>> > > >>>>>>>>>> Attached is the output from dmesg when this block of code: > > >>>>>>>>>> > > >>>>>>>>>> /bin/mount /dev/sda7 /mnt/sda7 > > >>>>>>>>>> /bin/mountpoint /proc || /bin/mount /proc > > >>>>>>>>>> /bin/dmesg -w > /mnt/sda7/sysrq.dmesg.log & > > >>>>>>>>>> /bin/echo t > /proc/sysrq-trigger > > >>>>>>>>>> /bin/sleep 1 > > >>>>>>>>>> /bin/sync > > >>>>>>>>>> /bin/sleep 1 > > >>>>>>>>>> kill $(pidof dmesg) > > >>>>>>>>>> /bin/umount /mnt/sda7 > > >>>>>>>>>> > > >>>>>>>>>> is executed immediately before /sbin/reboot is called as the final step of rebooting my system. > > >>>>>>>>>> > > >>>>>>>>>> I hope this is what you were looking for, but if not, please let me know what you need > > >>>>>>>> > > >>>>>>>> Thanks Dave. [...] > > >>>>>>> FWIW, in case anyone strands here in the archives: the msg was > > >>>>>>> truncated. The full post can be found in a new thread: > > >>>>>>> > > >>>>>>> https://lore.kernel.org/lkml/e0b80506-b3cf-315b-4327-1b988d86031e at googlemail.com/ > > >>>>>>> > > >>>>>>> Sadly it seems the info "With runpm=0, both reboot and poweroff work on > > >>>>>>> my laptop." didn't bring us much further to a solution. :-/ I don't > > >>>>>>> really like it, but for regression tracking I'm now putting this on the > > >>>>>>> back-burner, as a fix is not in sight. > > >>>>>>> > > >>>>>>> #regzbot monitor: > > >>>>>>> https://lore.kernel.org/lkml/e0b80506-b3cf-315b-4327-1b988d86031e at googlemail.com/ > > >>>>>>> #regzbot backburner: hard to debug and apparently rare > > >>>>>>> #regzbot ignore-activity > > >>>>>>> > > >>>>>> > > >>>>>> yeah.. this bug looks a little annoying. Sadly the only Turing based > > >>>>>> laptop I got doesn't work on Nouveau because of firmware related > > >>>>>> issues and we probably need to get updated ones from Nvidia here :( > > >>>>>> > > >>>>>> But it's a bit weird that the kernel doesn't shutdown, because I don't > > >>>>>> see anything in the logs which would prevent that from happening. > > >>>>>> Unless it's waiting on one of the tasks to complete, but none of them > > >>>>>> looked in any way nouveau related. > > >>>>>> > > >>>>>> If somebody else has any fancy kernel debugging tips here to figure > > >>>>>> out why it hangs, that would be very helpful... > > >>>>>> > > >>>>> > > >>>>> I think I've figured this out. It's to do with how my system is configured. I do have an initrd, but the only thing on > > >>>>> it is the cpu microcode which, it is recommended, should be loaded early. The absence of the NVidia firmare from an > > >>>>> initrd doesn't matter because the drivers for the hardware that need to load firmware are all built as modules, So, by > > >>>>> the time the devices are configured via udev, the root partition is mounted and the drivers can get at the firmware. > > >>>>> > > >>>>> I've found, by turning on nouveau debug and taking a video of the screen as the system shuts down, that nouveau seems to > > >>>>> be trying to run the scrubber very very late in the shutdown process. The problem is that by this time, I think the root > > >>>>> partition, and thus the scrubber binary, have become inaccessible. > > >>>>> > > >>>>> I seem to have two choices - either make the firmware accessible on an initrd or unload the module in a shutdown script > > >>>>> before the scrubber binary becomes inaccessible. The latter of these is the workaround I have implemented whilst the > > >>>>> problem I reported has been under investigation. For simplicity, I think I'll promote my workaround to being the > > >>>>> permanent solution. > > >>>>> > > >>>>> So, apologies (and thanks) to everyone whose time I have taken up with this non-bug. > > >>>>> > > >>>> > > >>>> Well.. nouveau shouldn't prevent the system from shutting down if the > > >>>> firmware file isn't available. Or at least it should print a > > >>>> warning/error. Mind messing with the code a little to see if skipping > > >>>> it kind of works? I probably can also come up with a patch by next > > >>>> week. > > >>>> > > >>> Well, I'd love to but a quick glance at the code caused me to bump into this obscenity: > > >>> > > >>> int > > >>> gm200_flcn_reset_wait_mem_scrubbing(struct nvkm_falcon *falcon) > > >>> { > > >>> nvkm_falcon_mask(falcon, 0x040, 0x00000000, 0x00000000); > > >>> > > >>> if (nvkm_msec(falcon->owner->device, 10, > > >>> if (!(nvkm_falcon_rd32(falcon, 0x10c) & 0x00000006)) > > >>> break; > > >>> ) < 0) > > >>> return -ETIMEDOUT; > > >>> > > >>> return 0; > > >>> } > > >>> > > >>> nvkm_msec is #defined to nvkm_usec which in turn is #defined to nvkm_nsec where the loop that the break is related to > > >>> appears > > >> > > >> I think someone who knows the code needs to look at this. What I can confirm is that after a freeze, I waited for 90 > > >> seconds for a timeout to occur, but it didn't. > > > Hey, > > > > > > Are you able to try the attached patch for me please? > > > > > > Thanks, > > > Ben. > > > > > > > Thanks Ben. > > > > Yes, this patch fixes the lockup on reboot and poweroff that I've been seeing on my laptop. As you would expect, > > offloaded rendering is still working and the discrete GPU is being powered on and off as required. > > > > Thanks. > > > > Reported-by: Chris Clayton <chris2553 at googlemail.com> > > Tested-by: Chris Clayton <chris2553 at googlemail.com> > > > > Ben, did you manage to get push rights to drm-misc by now or should I > just pick the patch and push it through -fixes?Feel free to pick it up! Thank you, Ben.> > > >> > > >> > > >> .> Chris > > >>>>> > > >>>>>>> Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) > > >>>>>>> -- > > >>>>>>> Everything you wanna know about Linux kernel regression tracking: > > >>>>>>> https://linux-regtracking.leemhuis.info/about/#tldr > > >>>>>>> That page also explains what to do if mails like this annoy you. > > >>>>>>> > > >>>>>>> #regzbot ignore-activity > > >>>>>>> > > >>>>>> > > >>>>> > > >>>> > > >