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Subject: Re: [PATCH 1/2] x86-64/setcontext: Pop the pointer into %rdx after
 syscall
To: "H.J. Lu" <hjl.tools@gmail.com>, GNU C Library <libc-alpha@sourceware.org>
References: <20180426121700.GA30766@intel.com>
From: Florian Weimer <fweimer@redhat.com>
Message-ID: <8b0e9b44-d231-ef32-05a7-5fad5c7352b1@redhat.com>
Date: Sun, 29 Apr 2018 21:03:00 -0000
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On 04/26/2018 02:17 PM, H.J. Lu wrote:
> +	/* Pop the pointer into RDX which is preserved by the syscall.  */
> +	popq	%rdx

Sorry, the comment is a bit unclear.  Why do you need to restore %rdx if 
it is preserved by the system call?  Maybe it becomes clearer with a 
future change?

Thanks,
Florian