Re: [Qemu-devel] Linux 2.6.15 hangs with QEMU 0.8.0

[Marius Groeger]

On Thu, 1 Jun 2006, Johannes Schindelin wrote:

> > with my qemu-0.8.0 I noticed that Linux 2.6.15 runs only with the appended
> > patch.
>
> Which patch?

Brilliant me. Sorry, I forgot the patch. I don't have it handy here at 
home, but it's easily described: in <asm-mips/hazards.h>, it made 
irq_enable_hazard emit 3 NOPs just as irq_disable_hazard. I stumbeled 
over this as my kernel hung im sched.c:wait_for_completionn(). Turned 
out that schedule() wasn't called properly which went away with the 
NOPs.

Again, I didn't really investigate too much, but I reckoned if the 
NOPS are needed upon irq_disable_hazard, they're needed for 
irq_enable_hazard as well, since CP0 status is write modified in both 
situations.

--
Marius Groeger <address@hidden>
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