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Groups > linux.kernel > #1590521 > unrolled thread
| Started by | Thomas Gleixner <tglx@linutronix.de> |
|---|---|
| First post | 2017-03-01 18:10 +0100 |
| Last post | 2017-03-02 04:40 +0100 |
| Articles | 10 — 3 participants |
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Re: PPro arch_cpu_idle: NMI watchdog: Watchdog detected hard LOCKUP on cpu 1 Thomas Gleixner <tglx@linutronix.de> - 2017-03-01 18:10 +0100
Re: PPro arch_cpu_idle: NMI watchdog: Watchdog detected hard LOCKUP on cpu 1 Thomas Gleixner <tglx@linutronix.de> - 2017-03-02 02:40 +0100
Re: PPro arch_cpu_idle: NMI watchdog: Watchdog detected hard LOCKUP on cpu 1 Thomas Gleixner <tglx@linutronix.de> - 2017-03-02 19:10 +0100
Re: PPro arch_cpu_idle: NMI watchdog: Watchdog detected hard LOCKUP on cpu 1 Meelis Roos <mroos@linux.ee> - 2017-03-03 02:40 +0100
Re: PPro arch_cpu_idle: NMI watchdog: Watchdog detected hard LOCKUP on cpu 1 Meelis Roos <mroos@linux.ee> - 2017-03-03 12:00 +0100
Re: PPro arch_cpu_idle: NMI watchdog: Watchdog detected hard LOCKUP on cpu 1 Thomas Gleixner <tglx@linutronix.de> - 2017-03-03 14:10 +0100
Re: PPro arch_cpu_idle: NMI watchdog: Watchdog detected hard LOCKUP on cpu 1 Meelis Roos <mroos@linux.ee> - 2017-03-05 21:50 +0100
Re: PPro arch_cpu_idle: NMI watchdog: Watchdog detected hard LOCKUP on cpu 1 Frederic Weisbecker <fweisbec@gmail.com> - 2017-03-06 00:30 +0100
Re: PPro arch_cpu_idle: NMI watchdog: Watchdog detected hard LOCKUP on cpu 1 Meelis Roos <mroos@linux.ee> - 2017-03-06 12:50 +0100
Re: PPro arch_cpu_idle: NMI watchdog: Watchdog detected hard LOCKUP on cpu 1 Meelis Roos <mroos@linux.ee> - 2017-03-02 04:40 +0100
| From | Thomas Gleixner <tglx@linutronix.de> |
|---|---|
| Date | 2017-03-01 18:10 +0100 |
| Subject | Re: PPro arch_cpu_idle: NMI watchdog: Watchdog detected hard LOCKUP on cpu 1 |
| Message-ID | <tgfVg-65H-17@gated-at.bofh.it> |
On Wed, 1 Mar 2017, Meelis Roos wrote: > This is on my trusty IBM PC365, dual Pentium Pro. 4.10 worked fine, > 4.10.0-09686-g9e314890292c and 4.10.0-10770-g2d6be4abf514 exhibit a > problem. Ocassionally NMI watchdog kicks in and discovers one of the > CPUs in LOCKUP. The system keeps running fine. The first lockup was > different, all the others were from arch_cpu_idle. Sometime ecey couple > of seconds (after some activity), sometimes nothing for a long time > (idle, no SSH logins). The only watchdog related patch which hit after 4.10 is: 8dcde9def5a1 kernel/watchdog.c: do not hardcode CPU 0 as the initial thread Can you try to revert that for a start? I'm not seeing why it should be the culprit from a quick glance, but ... Thanks, tglx
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| From | Thomas Gleixner <tglx@linutronix.de> |
|---|---|
| Date | 2017-03-02 02:40 +0100 |
| Message-ID | <tgnSN-3ew-9@gated-at.bofh.it> |
| In reply to | #1590521 |
On Thu, 2 Mar 2017, Meelis Roos wrote: > > > This is on my trusty IBM PC365, dual Pentium Pro. 4.10 worked fine, > > > 4.10.0-09686-g9e314890292c and 4.10.0-10770-g2d6be4abf514 exhibit a > > > problem. Ocassionally NMI watchdog kicks in and discovers one of the > > > CPUs in LOCKUP. The system keeps running fine. The first lockup was > > > different, all the others were from arch_cpu_idle. Sometime ecey couple > > > of seconds (after some activity), sometimes nothing for a long time > > > (idle, no SSH logins). > > > > The only watchdog related patch which hit after 4.10 is: > > > > 8dcde9def5a1 kernel/watchdog.c: do not hardcode CPU 0 as the initial thread > > > > Can you try to revert that for a start? I'm not seeing why it should be the > > culprit from a quick glance, but ... > > Reverting this patch does not help. I did not expect that, but excluding it was a valid shot in the dark. Thanmks for trying. To be honest, I have no idea what causes that at the moment, but I will come back to you tomorrow after thinking it through (with brain awake) how to debug this. Thanks, tglx
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| From | Thomas Gleixner <tglx@linutronix.de> |
|---|---|
| Date | 2017-03-02 19:10 +0100 |
| Message-ID | <tgDkR-63W-3@gated-at.bofh.it> |
| In reply to | #1590784 |
On Wed, 1 Mar 2017, Thomas Gleixner wrote: > On Thu, 2 Mar 2017, Meelis Roos wrote: > > > > > This is on my trusty IBM PC365, dual Pentium Pro. 4.10 worked fine, > > > > 4.10.0-09686-g9e314890292c and 4.10.0-10770-g2d6be4abf514 exhibit a > > > > problem. Ocassionally NMI watchdog kicks in and discovers one of the > > > > CPUs in LOCKUP. The system keeps running fine. The first lockup was > > > > different, all the others were from arch_cpu_idle. Sometime ecey couple > > > > of seconds (after some activity), sometimes nothing for a long time > > > > (idle, no SSH logins). > > > > > > The only watchdog related patch which hit after 4.10 is: > > > > > > 8dcde9def5a1 kernel/watchdog.c: do not hardcode CPU 0 as the initial thread > > > > > > Can you try to revert that for a start? I'm not seeing why it should be the > > > culprit from a quick glance, but ... > > > > Reverting this patch does not help. > > I did not expect that, but excluding it was a valid shot in the > dark. Thanmks for trying. > > To be honest, I have no idea what causes that at the moment, but I will > come back to you tomorrow after thinking it through (with brain awake) how > to debug this. Went through the related changes which came in during the merge window. One which affects the per cpu timers is: 914122c389d0 Can you try to revert that one please? Thanks, tglx
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| From | Meelis Roos <mroos@linux.ee> |
|---|---|
| Date | 2017-03-03 02:40 +0100 |
| Message-ID | <tgKml-2cx-7@gated-at.bofh.it> |
| In reply to | #1591366 |
> > > > > This is on my trusty IBM PC365, dual Pentium Pro. 4.10 worked fine, > > > > > 4.10.0-09686-g9e314890292c and 4.10.0-10770-g2d6be4abf514 exhibit a > > > > > problem. Ocassionally NMI watchdog kicks in and discovers one of the > > > > > CPUs in LOCKUP. The system keeps running fine. The first lockup was > > > > > different, all the others were from arch_cpu_idle. Sometime ecey couple > > > > > of seconds (after some activity), sometimes nothing for a long time > > > > > (idle, no SSH logins). > > > > > > > > The only watchdog related patch which hit after 4.10 is: > > > > > > > > 8dcde9def5a1 kernel/watchdog.c: do not hardcode CPU 0 as the initial thread > > > > > > > > Can you try to revert that for a start? I'm not seeing why it should be the > > > > culprit from a quick glance, but ... > > > > > > Reverting this patch does not help. > > > > I did not expect that, but excluding it was a valid shot in the > > dark. Thanmks for trying. > > > > To be honest, I have no idea what causes that at the moment, but I will > > come back to you tomorrow after thinking it through (with brain awake) how > > to debug this. > > Went through the related changes which came in during the merge window. One > which affects the per cpu timers is: 914122c389d0 > > Can you try to revert that one please? Reverted, no effect. -- Meelis Roos (mroos@linux.ee)
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| From | Meelis Roos <mroos@linux.ee> |
|---|---|
| Date | 2017-03-03 12:00 +0100 |
| Message-ID | <tgT6i-8tS-17@gated-at.bofh.it> |
| In reply to | #1591366 |
> On Thu, 2 Mar 2017, Thomas Gleixner wrote: > > On Wed, 1 Mar 2017, Thomas Gleixner wrote: > > > On Thu, 2 Mar 2017, Meelis Roos wrote: > > > > > > > > > This is on my trusty IBM PC365, dual Pentium Pro. 4.10 worked fine, > > > > > > 4.10.0-09686-g9e314890292c and 4.10.0-10770-g2d6be4abf514 exhibit a > > > > > > problem. Ocassionally NMI watchdog kicks in and discovers one of the > > > > > > CPUs in LOCKUP. The system keeps running fine. The first lockup was > > > > > > different, all the others were from arch_cpu_idle. Sometime ecey couple > > > > > > of seconds (after some activity), sometimes nothing for a long time > > > > > > (idle, no SSH logins). > > > > > > > > > > The only watchdog related patch which hit after 4.10 is: > > > > > > > > > > 8dcde9def5a1 kernel/watchdog.c: do not hardcode CPU 0 as the initial thread > > > > > > > > > > Can you try to revert that for a start? I'm not seeing why it should be the > > > > > culprit from a quick glance, but ... > > > > > > > > Reverting this patch does not help. > > > > > > I did not expect that, but excluding it was a valid shot in the > > > dark. Thanmks for trying. > > > > > > To be honest, I have no idea what causes that at the moment, but I will > > > come back to you tomorrow after thinking it through (with brain awake) how > > > to debug this. > > > > Went through the related changes which came in during the merge window. One > > which affects the per cpu timers is: 914122c389d0 > > > > Can you try to revert that one please? > > Running out of obvious culprits. Any chance that you can do a bisect or > this too painful on that box? I started bisect yesterday on the P4 that has one similar occurrance. -- Meelis Roos (mroos@linux.ee)
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| From | Thomas Gleixner <tglx@linutronix.de> |
|---|---|
| Date | 2017-03-03 14:10 +0100 |
| Message-ID | <tgT6i-8tS-19@gated-at.bofh.it> |
| In reply to | #1591366 |
On Thu, 2 Mar 2017, Thomas Gleixner wrote: > On Wed, 1 Mar 2017, Thomas Gleixner wrote: > > On Thu, 2 Mar 2017, Meelis Roos wrote: > > > > > > > This is on my trusty IBM PC365, dual Pentium Pro. 4.10 worked fine, > > > > > 4.10.0-09686-g9e314890292c and 4.10.0-10770-g2d6be4abf514 exhibit a > > > > > problem. Ocassionally NMI watchdog kicks in and discovers one of the > > > > > CPUs in LOCKUP. The system keeps running fine. The first lockup was > > > > > different, all the others were from arch_cpu_idle. Sometime ecey couple > > > > > of seconds (after some activity), sometimes nothing for a long time > > > > > (idle, no SSH logins). > > > > > > > > The only watchdog related patch which hit after 4.10 is: > > > > > > > > 8dcde9def5a1 kernel/watchdog.c: do not hardcode CPU 0 as the initial thread > > > > > > > > Can you try to revert that for a start? I'm not seeing why it should be the > > > > culprit from a quick glance, but ... > > > > > > Reverting this patch does not help. > > > > I did not expect that, but excluding it was a valid shot in the > > dark. Thanmks for trying. > > > > To be honest, I have no idea what causes that at the moment, but I will > > come back to you tomorrow after thinking it through (with brain awake) how > > to debug this. > > Went through the related changes which came in during the merge window. One > which affects the per cpu timers is: 914122c389d0 > > Can you try to revert that one please? Running out of obvious culprits. Any chance that you can do a bisect or this too painful on that box? Thanks, tglx
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| From | Meelis Roos <mroos@linux.ee> |
|---|---|
| Date | 2017-03-05 21:50 +0100 |
| Message-ID | <thLgl-5Fg-7@gated-at.bofh.it> |
| In reply to | #1591925 |
Added some CC-s because of bisect find. Whole context should be still
here.
> > > > > > This is on my trusty IBM PC365, dual Pentium Pro. 4.10 worked fine,
> > > > > > 4.10.0-09686-g9e314890292c and 4.10.0-10770-g2d6be4abf514 exhibit a
> > > > > > problem. Ocassionally NMI watchdog kicks in and discovers one of the
> > > > > > CPUs in LOCKUP. The system keeps running fine. The first lockup was
> > > > > > different, all the others were from arch_cpu_idle. Sometime ecey couple
> > > > > > of seconds (after some activity), sometimes nothing for a long time
> > > > > > (idle, no SSH logins).
> > > > >
> > > > > The only watchdog related patch which hit after 4.10 is:
> > > > >
> > > > > 8dcde9def5a1 kernel/watchdog.c: do not hardcode CPU 0 as the initial thread
> > > > >
> > > > > Can you try to revert that for a start? I'm not seeing why it should be the
> > > > > culprit from a quick glance, but ...
> > > >
> > > > Reverting this patch does not help.
> > >
> > > I did not expect that, but excluding it was a valid shot in the
> > > dark. Thanmks for trying.
> > >
> > > To be honest, I have no idea what causes that at the moment, but I will
> > > come back to you tomorrow after thinking it through (with brain awake) how
> > > to debug this.
> >
> > Went through the related changes which came in during the merge window. One
> > which affects the per cpu timers is: 914122c389d0
> >
> > Can you try to revert that one please?
>
> Running out of obvious culprits. Any chance that you can do a bisect or
> this too painful on that box?
Done on a P4 where the problem also appeared. The bisecting resulted in
this commit. Does it seem realistic? I will also try if this help son
the old PPro.
93825f2ec736f30e034ab7c9d56b42849c5b00da is the first bad commit
commit 93825f2ec736f30e034ab7c9d56b42849c5b00da
Author: Frederic Weisbecker <fweisbec@gmail.com>
Date: Tue Jan 31 04:09:16 2017 +0100
jiffies: Reuse TICK_NSEC instead of NSEC_PER_JIFFY
NSEC_PER_JIFFY is an ad-hoc redefinition of TICK_NSEC. Let's rather
use a unique and well maintained version.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1485832191-26889-1-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
:040000 040000 219afc6bb9e757532791f93ed05ddf68a7124cb0 fb9cc12366f970c1bc4872cc38b1c4df5ce9594d M kernel
--
Meelis Roos (mroos@linux.ee)
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| From | Frederic Weisbecker <fweisbec@gmail.com> |
|---|---|
| Date | 2017-03-06 00:30 +0100 |
| Message-ID | <thNLc-7B0-5@gated-at.bofh.it> |
| In reply to | #1592839 |
On Sun, Mar 05, 2017 at 10:48:50PM +0200, Meelis Roos wrote: > Added some CC-s because of bisect find. Whole context should be still > here. > > > > > > > > This is on my trusty IBM PC365, dual Pentium Pro. 4.10 worked fine, > > > > > > > 4.10.0-09686-g9e314890292c and 4.10.0-10770-g2d6be4abf514 exhibit a > > > > > > > problem. Ocassionally NMI watchdog kicks in and discovers one of the > > > > > > > CPUs in LOCKUP. The system keeps running fine. The first lockup was > > > > > > > different, all the others were from arch_cpu_idle. Sometime ecey couple > > > > > > > of seconds (after some activity), sometimes nothing for a long time > > > > > > > (idle, no SSH logins). > > > > > > > > > > > > The only watchdog related patch which hit after 4.10 is: > > > > > > > > > > > > 8dcde9def5a1 kernel/watchdog.c: do not hardcode CPU 0 as the initial thread > > > > > > > > > > > > Can you try to revert that for a start? I'm not seeing why it should be the > > > > > > culprit from a quick glance, but ... > > > > > > > > > > Reverting this patch does not help. > > > > > > > > I did not expect that, but excluding it was a valid shot in the > > > > dark. Thanmks for trying. > > > > > > > > To be honest, I have no idea what causes that at the moment, but I will > > > > come back to you tomorrow after thinking it through (with brain awake) how > > > > to debug this. > > > > > > Went through the related changes which came in during the merge window. One > > > which affects the per cpu timers is: 914122c389d0 > > > > > > Can you try to revert that one please? > > > > Running out of obvious culprits. Any chance that you can do a bisect or > > this too painful on that box? > > Done on a P4 where the problem also appeared. The bisecting resulted in > this commit. Does it seem realistic? I will also try if this help son > the old PPro. > > 93825f2ec736f30e034ab7c9d56b42849c5b00da is the first bad commit > commit 93825f2ec736f30e034ab7c9d56b42849c5b00da > Author: Frederic Weisbecker <fweisbec@gmail.com> > Date: Tue Jan 31 04:09:16 2017 +0100 > > jiffies: Reuse TICK_NSEC instead of NSEC_PER_JIFFY > > NSEC_PER_JIFFY is an ad-hoc redefinition of TICK_NSEC. Let's rather > use a unique and well maintained version. > > Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> > Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> > Cc: Paul Mackerras <paulus@samba.org> > Cc: Michael Ellerman <mpe@ellerman.id.au> > Cc: Heiko Carstens <heiko.carstens@de.ibm.com> > Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> > Cc: Tony Luck <tony.luck@intel.com> > Cc: Fenghua Yu <fenghua.yu@intel.com> > Cc: Peter Zijlstra <peterz@infradead.org> > Cc: Rik van Riel <riel@redhat.com> > Cc: Stanislaw Gruszka <sgruszka@redhat.com> > Cc: Wanpeng Li <wanpeng.li@hotmail.com> > Link: http://lkml.kernel.org/r/1485832191-26889-1-git-send-email-fweisbec@gmail.com > Signed-off-by: Ingo Molnar <mingo@kernel.org> Ouch, looking at that patch again, I probably had a delusional moment when I wrote this: diff --git a/kernel/time/jiffies.c b/kernel/time/jiffies.c index a4a0e47..7906b3f 100644 --- a/kernel/time/jiffies.c +++ b/kernel/time/jiffies.c @@ -125,7 +125,7 @@ int register_refined_jiffies(long cycles_per_second) shift_hz += cycles_per_tick/2; do_div(shift_hz, cycles_per_tick); /* Calculate nsec_per_tick using shift_hz */ - nsec_per_tick = (u64)NSEC_PER_SEC << 8; + nsec_per_tick = (u64)TICK_NSEC << 8; nsec_per_tick += (u32)shift_hz/2; do_div(nsec_per_tick, (u32)shift_hz); Could you please retry after reverting this specific chunk? (that would be the very fix to apply). Thanks!
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| From | Meelis Roos <mroos@linux.ee> |
|---|---|
| Date | 2017-03-06 12:50 +0100 |
| Message-ID | <thZjl-7C0-25@gated-at.bofh.it> |
| In reply to | #1592860 |
> On Sun, Mar 05, 2017 at 10:48:50PM +0200, Meelis Roos wrote: > > Added some CC-s because of bisect find. Whole context should be still > > here. > > > > > > > > > > This is on my trusty IBM PC365, dual Pentium Pro. 4.10 worked fine, > > > > > > > > 4.10.0-09686-g9e314890292c and 4.10.0-10770-g2d6be4abf514 exhibit a > > > > > > > > problem. Ocassionally NMI watchdog kicks in and discovers one of the > > > > > > > > CPUs in LOCKUP. The system keeps running fine. The first lockup was > > > > > > > > different, all the others were from arch_cpu_idle. Sometime ecey couple > > > > > > > > of seconds (after some activity), sometimes nothing for a long time > > > > > > > > (idle, no SSH logins). > > > > > > > > > > > > > > The only watchdog related patch which hit after 4.10 is: > > > > > > > > > > > > > > 8dcde9def5a1 kernel/watchdog.c: do not hardcode CPU 0 as the initial thread > > > > > > > > > > > > > > Can you try to revert that for a start? I'm not seeing why it should be the > > > > > > > culprit from a quick glance, but ... > > > > > > > > > > > > Reverting this patch does not help. > > > > > > > > > > I did not expect that, but excluding it was a valid shot in the > > > > > dark. Thanmks for trying. > > > > > > > > > > To be honest, I have no idea what causes that at the moment, but I will > > > > > come back to you tomorrow after thinking it through (with brain awake) how > > > > > to debug this. > > > > > > > > Went through the related changes which came in during the merge window. One > > > > which affects the per cpu timers is: 914122c389d0 > > > > > > > > Can you try to revert that one please? > > > > > > Running out of obvious culprits. Any chance that you can do a bisect or > > > this too painful on that box? > > > > Done on a P4 where the problem also appeared. The bisecting resulted in > > this commit. Does it seem realistic? I will also try if this help son > > the old PPro. > > > > 93825f2ec736f30e034ab7c9d56b42849c5b00da is the first bad commit > > commit 93825f2ec736f30e034ab7c9d56b42849c5b00da > > Author: Frederic Weisbecker <fweisbec@gmail.com> > > Date: Tue Jan 31 04:09:16 2017 +0100 > > > > jiffies: Reuse TICK_NSEC instead of NSEC_PER_JIFFY [...] > Ouch, looking at that patch again, I probably had a delusional moment when I wrote this: > > diff --git a/kernel/time/jiffies.c b/kernel/time/jiffies.c > index a4a0e47..7906b3f 100644 > --- a/kernel/time/jiffies.c > +++ b/kernel/time/jiffies.c > @@ -125,7 +125,7 @@ int register_refined_jiffies(long cycles_per_second) > shift_hz += cycles_per_tick/2; > do_div(shift_hz, cycles_per_tick); > /* Calculate nsec_per_tick using shift_hz */ > - nsec_per_tick = (u64)NSEC_PER_SEC << 8; > + nsec_per_tick = (u64)TICK_NSEC << 8; > nsec_per_tick += (u32)shift_hz/2; > do_div(nsec_per_tick, (u32)shift_hz); > > > > Could you please retry after reverting this specific chunk? (that would be the very fix > to apply). Reverting this chunk fixed both the PPro and the P4. -- Meelis Roos (mroos@linux.ee)
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| From | Meelis Roos <mroos@linux.ee> |
|---|---|
| Date | 2017-03-02 04:40 +0100 |
| Message-ID | <tgnSN-3ew-11@gated-at.bofh.it> |
| In reply to | #1590521 |
> > This is on my trusty IBM PC365, dual Pentium Pro. 4.10 worked fine, > > 4.10.0-09686-g9e314890292c and 4.10.0-10770-g2d6be4abf514 exhibit a > > problem. Ocassionally NMI watchdog kicks in and discovers one of the > > CPUs in LOCKUP. The system keeps running fine. The first lockup was > > different, all the others were from arch_cpu_idle. Sometime ecey couple > > of seconds (after some activity), sometimes nothing for a long time > > (idle, no SSH logins). > > The only watchdog related patch which hit after 4.10 is: > > 8dcde9def5a1 kernel/watchdog.c: do not hardcode CPU 0 as the initial thread > > Can you try to revert that for a start? I'm not seeing why it should be the > culprit from a quick glance, but ... Reverting this patch does not help. -- Meelis Roos (mroos@linux.ee)
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