Re: [PATCH 3/3] i386: use ACPI to power off the machine

[David Michael]

On Tue, Jul 1, 2014 at 5:23 AM, Justus Winter
<4winter@informatik.uni-hamburg.de> wrote:
> Quoting David Michael (2014-06-23 00:31:57)
>> Hi,
>>
>> On Sat, May 3, 2014 at 4:56 AM, Justus Winter
>> <4winter@informatik.uni-hamburg.de> wrote:
>> > However, when I use --enable-device-drivers=qemu it doesn't work:
>> >
>> > db> halt
>> > Looking for RSDP. Scanning EBDA
>> > Looking for RSDP. Scanning EBDA
>> > rsdp1=0
>> >
>> > Hum.  Maybe someone overwrote our precious EBDA table (whatever that
>> > is).  It's supposed to be around physical address 0x40e.  See acpi.c
>> > for the code looking for the RSDP.
>>
>> It seems to work when acpi.c is patched to use the "Scanning BIOS"
>> sections if it can't get the EDBA length.  Changing "if (! ebda_len)
>> return 0;" to just "if (edba_len)" does the trick, making the first
>> loop conditional instead of calling off the search.
>
> If you can get it to work, then by all means, please do it :)

I've sent a patch that makes the described change, and I've been using
it with QEMU for a week or two without issues so far.

Thanks for working on this functionality; it's really useful.

David