> > This reverts commit 406663ed61c8ad2b792824af1c1bc0e4faa711c6. With
> > BPREDICT enabled, my Lager board can't boot anymore and gets stuck
> > early in the boot process (mostly without any printout, sometimes with a
> > little printout)
>
> And it just stops without printing anything special?
Yes. The only notable difference I recognized in the output was the set
bit for branch prediction in the cr register output. That's why I
assumed this commit to be guilty...
>
> > Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
>
> I suspect you're bitten by the issue from "RCU lockup? (was: Re: [PATCH v2
> tip/core/rcu 10/14] rcu: Don't redundantly disable irqs in
> rcu_irq_{enter,exit}())" (http://www.spinics.net/lists/kernel/msg2167464.html).
... but it seems you are right on the spot here. Thanks!
> Does it help if you add a function
>
> void filler(void)
> {
> asm("nop");
> asm("nop");
> }
Adding 21 nops made the board boot again. (Wow, adding NOPs everywhere
really feels like hacking the Commodore 64 when trying to get the timing
stable :D)
This is gonna be a nasty one :(
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