[Qemu-devel] Re: sparc32 do not clear interrupts when masking

[Blue Swirl <blauwirbel@gmail.com>]

On Sat, Jan 16, 2010 at 8:47 AM, Blue Swirl <blauwirbel@gmail.com> wrote:
> On Sat, Jan 16, 2010 at 8:16 AM, Blue Swirl <blauwirbel@gmail.com> wrote:
>> On Fri, Jan 15, 2010 at 10:37 PM, Artyom Tarasenko
>> <atar4qemu@googlemail.com> wrote:
>>> Don't clear interrupts on disabling, because
>>> * Sun4M_SystemArchitecture_edited2.pdf doesn't describe
>>>  that masking or un-masking IRQ shall clear pending ones.
>>>
>>> * Field tests also show that SPARCstation-20 doesn't
>>>  clear them.
>>
>> Awesome work!
>>
>>> * The patch makes Solaris 2.5.1/2.6 boot ~1500 times
>>>  faster (~20 seconds instead of ~8 hours)
>>
>> Unfortunately there is some problem with the patch (or more likely
>> there is some other bug that this uncovers), because all my Linux test
>> now panic. NetBSD and OpenBSD are unaffected.
>>
>> For example, sparc-test:
>> eth0: LANCE 52:54:00:12:34:56
>> esp0: no command in esp_handle()
>> Kernel panic - not syncing: esp_handle: current_SC == penguin within interrupt!
>>  <0>Press L1-A to return to the boot prom
>>
>> The bug may be in ESP interrupt handling (or in the interrupt chain
>> between ESP, DMA controller and interrupt controller) as the panic
>> always happens in ESP probe.
>
> In fact the bug was that OpenBIOS didn't clear ESP interrupts after
> issuing commands, so the IRQ line was left raised which confused
> Linux.
>

Thanks, applied. I fixed the OpenBIOS bug and updated images in pc-bios.