Re: [patch, 2.6.22-rc6] fix nmi_watchdog=2 bootup hang

Björn Steinbrink
2007-06-25T12:44:55Z

On 2007.06.25 10:26:52 +0200, Ingo Molnar wrote:
>
> * Ingo Molnar <mingo@elte.hu> wrote:
>
> > the winner is ...
> >
> > f8822f42019eceed19cc6c0f985a489e17796ed8 is first bad commit
> > commit f8822f42019eceed19cc6c0f985a489e17796ed8
> > Author: Jeremy Fitzhardinge <jeremy@goop.org>
> > Date: Wed May 2 19:27:14 2007 +0200
> >
> > [PATCH] i386: PARAVIRT: Consistently wrap paravirt ops callsites to make them patchable
>
> and of course i'm happy to test any patch that is simpler than the
> brutal revert i sent.

wrmsrl() looks broken, dropping the upper 32bits of the value to be
written. Does this help?

Björn
---
diff --git a/include/asm-i386/paravirt.h b/include/asm-i386/paravirt.h
index d7a0512..7f846a7 100644
--- a/include/asm-i386/paravirt.h
+++ b/include/asm-i386/paravirt.h
@@ -539,7 +539,7 @@ static inline int paravirt_write_msr(unsigned msr, unsigned low, unsigned high)
val = paravirt_read_msr(msr, &_err); \
} while(0)

-#define wrmsrl(msr,val) ((void)paravirt_write_msr(msr, val, 0))
+#define wrmsrl(msr,val) wrmsr(msr, (u32)((u64)(val)), ((u64)(val))>>32)
#define wrmsr_safe(msr,a,b) paravirt_write_msr(msr, a, b)

/* rdmsr with exception handling */