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From: Florian Weimer <fweimer@redhat.com>
To: Walt Drummond via Gdb <gdb@sourceware.org>
Cc: Tom Tromey <tom@tromey.com>,  Walt Drummond <walt@drummond.us>
Subject: Re: AMD64_LINUX_frame_size
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Date: Mon, 11 Jan 2021 11:43:05 +0100
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 (Walt Drummond via Gdb's message of "Thu, 7 Jan 2021 13:49:50 -0800")
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* Walt Drummond via Gdb:

> Thanks Tom.  My math shows the kernel sizes as
> Redzone 128
> math frame/xstate 840
> rt_sigframe 456
>
> That's a total of 1424 bytes, so maybe GDB is saving less than it should?

With AVX-512, the kernel size is way larger.

Do you know for what purpose GDB needs this information?  Decoding the
xstate is quite complicated as far as I know.  Is it related to
preserving stack contents across signal delivery?

Thanks,
Florian
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