RE: [外部邮件] Re: [PATCH][v2] hung_task: Panic after fixed number of hung tasks

[Li,Rongqing]

> On October 10, 2025 5:25:05 PM PDT, Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> wrote:
> >Hi,
> >
> >On 9/27/25 10:31 PM, lirongqing wrote:
> >> From: Li RongQing <lirongqing@xxxxxxxxx>
> >>
> >> Currently, when hung_task_panic is enabled, kernel will panic
> >> immediately upon detecting the first hung task. However, some hung
> >> tasks are transient and the system can recover fully, while others
> >> are unrecoverable and trigger consecutive hung task reports, and a panic is
> expected.
> >>
> >> This commit adds a new sysctl parameter hung_task_count_to_panic to
> >> allows specifying the number of consecutive hung tasks that must be
> >> detected
> 
> Why make a new sysctl? Can't you just use hung_task_panic and raise the max
> to INT_MAX?
> 


However, this will prevent the printing of hung task warnings. Hung task warnings are very useful for identifying which tasks are hanging and where they are stuck.

If there is this function, I hope to shorten sysctl_hung_task_timeout_secs to give more information.

And rcu has the similar function as dfe564045c653d "(rcu: Panic after fixed number of stalls)"

-Li