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Subject: Re: [RFC 3/4] x86/signal/64: Re-add support for SS in the 64-bit
 signal context
To: Andy Lutomirski <luto@amacapital.net>
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Cc: Denys Vlasenko <dvlasenk@redhat.com>,
        Pavel Emelyanov <xemul@parallels.com>, Borislav Petkov <bp@alien8.de>,
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From: Stas Sergeev <stsp@list.ru>
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Date: Sun, 18 Oct 2015 19:29:03 +0300
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18.10.2015 19:12, Andy Lutomirski пишет:
> On Sun, Oct 18, 2015 at 6:36 AM, Stas Sergeev <stsp@list.ru> wrote:
>> 15.10.2015 00:41, Andy Lutomirski пишет:
>>>> If this my
>>>> understanding is correct and the flag is just an indication rather
>>>> than a requested action, perhaps the name should be different,
>>>> e.g. UC_SIG_FROM_32BIT or the like?
>>>> Anyway, this is minor. :)
>>>> I'll try to test the patch within a few days, thanks for you time!
>>> No problem.  Thanks for being willing to test!
>> Hello Andy, I am unlucky at testing this.
>> dosemu doesn't even start for me on the git kernels.
>> After a half day of debugging, it seems the kernel forgets
>> to fill in the "err" field in the sigcontext struct when
>> page fault occurs. That confuses the dosemu's instruction
>> decoder.
>> Does this ring any bells?
> No, but I can reproduce it on some kernels.  Let me see if I can fix it, too.
Thanks!
You should really consider adding dosemu as your test-case.
It feels very unhappy on all recent kernels. I was getting hard
lock-ups under different circumstances (when starting windows,
for example). But fedora-packaged kernels are quite good, as of
yet. I fear the problems will soon populate to them too.