RE: [Xen-devel] guest attempted write to read-only memory page.

["Tian, Kevin" <kevin.tian@xxxxxxxxx>]

>From: Tian, Kevin
>Sent: Monday, December 22, 2008 9:11 PM
>>
>>Possibly we should silence the shadow code too, at least 
>>perhaps while in
>>real mode or for a certain EIP range.
>>
>
>I'm not sure that's the right fix. Why is write access to rom disabled
>before rom scan when etherboot is known to have write requirement?
>
>#ifdef HVMASSIST
>  call _enable_rom_write_access
>  call _clobber_entry_point
>  call _copy_e820_table
>  call smbios_init
>  call _disable_rom_write_access
>#endif
>
>  call _init_boot_vectors
>
>  mov  cx, #0xc800  ;; init option roms
>  mov  ax, #0xe000
>  call rom_scan
>
>Should we move disable action to post rom_scan? If shadow warning
>is simply silenced for such case, it seems breaking the purpose of
>disable_dom_write_access...
>

I make a quick test, that warning disappears after moving disable
action post rom_scan. But I haven't found the place triggering such
write violation, as in previous revision write access is also disabled
before rom_scan. It could come from recent bochs update on 
expansion rom part by 18931.

Thanks,
Kevin
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel