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Subject: Re: [PATCH] clocksource: disable irq when holding watchdog_lock.
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On 2023/10/17 23:10, Paul E. McKenney wrote:
>> But I'm hitting something different (but might be timer/scheduler related) problem.
>> What config option would cause taking more than 2 minutes to bring up only 8 CPUs?
>> (This environment is Oracle VM VirtualBox on Windows 11 host.)
>>
> The timing is about the same in both cases.  Does this happen in kernels
> built with CONFIG_PROVE_LOCKING=n?

Disabling all options in "Lock Debugging (spinlocks, mutexes, etc...)" does not help.

> 
> Either way, what mainline or -stable version is this?

The kernel is latest commit of upstream linux.git tree.
I'm seeing this slowdown (almost hung-up) problem for many releases,
but nobody else seems to be reporting this problem.

The only reliable workaround is to specify "nosmp" kernel command line option.