Re: [PATCH RT 10/30] hrtimer: Prevent using hrtimer_grab_expiry_lock() on migration_base

[Steven Rostedt]

On Mon, 27 Apr 2020 15:10:00 +0200
Rasmus Villemoes <rasmus.villemoes@xxxxxxxxx> wrote:

> However, building with their rescue initrd and booting that, the board
> would consistently hang during reboot. Sometimes I would get lines like
> 
> [   72.956630] sched: RT throttling activated
> [   72.973769] lanx: port 1(lan1) entered disabled state
> [   73.000401] lanx: port 2(lan2) entered disabled state
> [   73.974951] lanx: port 3(lan3) entered disabled state
> [   73.997473] lanx: port 4(lan4) entered disabled state
> [   74.968006] lanx: port 5(lan5) entered disabled state
> 
> other times there would be no output, but the board was still hanging.
> Reverting
> 
> b1a471ec4df1 - hrtimer: Prevent using hrtimer_grab_expiry_lock() on
> migration_base
> 40aae5708e7a - hrtimer: Add a missing bracket and hide `migration_base'
> on !SMP
> 
> on top of v4.19.94-rt39 makes that problem go away, i.e. the board
> reboots as expected.
> 
> The board is a 32 bit powerpc (mpc8309) !SMP. Any ideas what I can do to
> debug this further?

Thanks Rasmus for looking into this. Tom now maintains 4.19-rt.

Tom, care to pull in these patches on top of 4.19-rt?

-- Steve