BTX loader hangs after version info
Mark Kirkwood
markir at paradise.net.nz
Mon May 26 02:23:35 UTC 2008
Peter Holm wrote:
> On Sun, May 25, 2008 at 08:33:01PM +1200, Mark Kirkwood wrote:
>
>> I wrote:
>>
>>> John Baldwin wrote:
>>>
>>>> Try this patch. I'm not 100% certain this will fix it as I can't
>>>> reproduce
>>>> the issue, but I think it might help. Specifically, when the boot
>>>> code makes
>>>> a v86 call, the loader/boot2/whatever swaps in/out a new set of
>>>> registers via
>>>> the v86 structure including the eflags register. However, none of
>>>> the boot
>>>> programs actually initialized the v86 structure. Thus, the BIOS
>>>> routines
>>>> would start off running with whatever garbage was in v86.efl when
>>>> each boot
>>>> program started. This meant that we could end up invoking BIOS
>>>> routines with
>>>> interrupts disabled, and I think this might explain a hard hang (if a
>>>> BIOS
>>>> routine was waiting for an interrupt the interrupt would never
>>>> fire). The
>>>> patch fixes all the boot programs to initialize v86 to a better known
>>>> state. At the least it sets v86.efl to a sane value (0x202) rather
>>>> than random. (The
>>>> random might have always been 0x0 BTW, not sure on that one.)
>>>>
>>>>
>>>>
>>> Thanks John,
>>>
>>> Unfortunately this patch does *not* cure the issue for my old
>>> Supermicro P3TDDE, it still hangs just before presenting the menu. I
>>> had to boot off the livefs and copy /boot/loader.old -> /boot/loader
>>> to get back to being bootable again - but at least the old fella is on
>>> a more up-to-date 7-STABLE now :-)
>>>
>> Given that the patch *did* cure Peters Tyan S2720, I'll double check I
>> didn't fat finger applying the patch (mind you the Tyan has AMI BOIS -
>> same as my Supermicro P3TDERs that *do* work ok with current 7-STABLE,
>> whereas the P3TDDE has Award BIOS).
>>
>> Anyway, I'll double check and report back...
>>
>> Cheers
>>
>> Mark
>>
>
> I did 18 boots with and with out John's patch. With the patch I got 6
> actual boots and 12 hangs in the loaders progress bar.
>
> Without the patch I got 10 boots and 8 hangs.
>
> But, my Tyan M/B is old and with known ACPI issues so I'm not sure if
> this is of much value.
>
> Mark, it would be nice if you also observe if a sequence of reboots
> eventually boots your system. My longest bad streek was 8 reboots.
>
>
Yeah, I see the same thing - with John's patch applied, out of 9 reboots
I got 7 hangs and 2 actual boots. (didn't try without the patch).
Mark
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