Re: [Qemu-devel] [SeaBIOS] (PAM stuff) reset doesn't work on OVMF + SeaBIOS CSM

[David Woodhouse]

On Fri, 2013-02-15 at 11:19 +0400, Michael Tokarev wrote:
> This patch is more than 2 years old and is applied to all more or
> less recent qemu versions. 

RHEL 6.3?

I'm *not* seeing this bug with recent qemu versions.

>  This does not tell us why disabling kvm (with this patch applied!)
> makes a difference.  So there must be another (maybe similar) bug
> somewhere...

Are you looking at the same patch I'm looking at? Before the patch, if
KVM is enabled then the i440fx_update_memory_mappings() function just
bails out without doing anything. As the commit message describes, it
fails to remap the 0xf0000 memory from ROM to RAM, so subsequent writes
to the F-segment actually modify the *ROM* content instead of the RAM
copy as they should. (KVM doesn't write-protect the ROM). So on reset,
it ends up running the *modified* copy of the BIOS.

That's an *exact* description of what Laszlo was seeing, surely?

-- 
dwmw2

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