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From: Walt Drummond <walt@drummond.us>
Date: Wed, 6 Jan 2021 08:38:59 -0800
Message-ID: <CADCN6nxVYmjS+D0VX5-DqRTvf-Xc-EjN7cJ1vRyehg+vV6tVig@mail.gmail.com>
Subject: Re: AMD64_LINUX_frame_size
To: gdb@sourceware.org
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After looking at this further, I think I understand AMD64_LINUX_frame_size
and why it differs from the size of the kernel's rt_sigframe (differences
between glibc's and the kernels' definition of sigset_t), but I don't
understand how GDB arrived at 512 for AMD_LINUX_xstate.  The kernel's math
frame, which also contains the extended state information, is 840 bytes.  I
feel I must be missing something.  Any pointers?

Thanks.

On Mon, Jan 4, 2021 at 10:30 AM Walt Drummond <walt@drummond.us> wrote:

> I'm trying to understand the relationship between the
> AMD64_LINUX_frame_size constant and the kernel's signal stack layout.  Is
> there any documentation or commentary that describes how we got to the
> current value?
>
> Thanks.
>
>