restart callback not supposed to sleep?

Lothar Waßmann LW at
Mon Aug 20 04:57:34 EDT 2012


Uwe Kleine-König writes:
> Hello,
> while triggering a reboot via sysrq on an ARM machine I saw a "BUG:
> sleeping function called from invalid context" message (details below).
> The reason is that the sysrq handler is calling the restart hook in irq
> context. So what should be done about that? The obvious possiblities
> are:
>  a) ignore the problem as it won't result in problems (and maybe somehow
>     silence the warnign); or
>  b) make the restart hook atomic; or
>  c) assert sysrq not calling the hook in atomic mode
> What do you think?
This has been discussed earlier (with your participation) with 'a)'
being the conclusion.

Lothar Waßmann

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