Message-ID: <53612634.2070802@zytor.com>
Date: Wed, 30 Apr 2014 09:35:00 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Mark Kettenis <mark.kettenis@xs4all.nl>
CC: pinskia@gmail.com, teawater@gmail.com, tglx@linutronix.de,
        mingo@redhat.com, x86@kernel.org, eparis@redhat.com,
        ak@linux.intel.com, linux-kernel@vger.kernel.org, gdb@sourceware.org
Subject: Re: [PATCH] Fix get ERESTARTSYS with m32 in x86_64 when debug by
 GDB
References: <CANFwon0oLO+qCtpewc=BxKBOm05aBMpV=yG0CxwW1isWHfnZqw@mail.gmail.com>	<53554846.3070608@zytor.com>	<CANFwon3zA9FMujmnN3nMiv8Zr8bU9o72XXa26dkePNq57U=JcQ@mail.gmail.com>	<53608125.2020103@zytor.com> <CA+=Sn1=y-smZOaD_yRxEwgu-PPaZYdQtB_RGPCA5-9wmB6=hvQ@mail.gmail.com> <536085B7.5070002@zytor.com> <201404301335.s3UDZX4J017978@glazunov.sibelius.xs4all.nl>
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On 04/30/2014 06:35 AM, Mark Kettenis wrote:
> 
> If (and only if) the goal of that TS_COMPAT flag solely is to trigger
> the error code sign-extension in arch/x86/asm/syscall.h:syscall_get_error(),
> we could work around to problem in GDB by checking "orig_ax" to see if
> we're continuing an interrupted system call and sign extend the error
> code in the real "eax" register if we are.
> 

Well... this "if and only if" clause is false, although it might work
specifically in this context.  I need to do a writeup about this... I
should try to do that today.

	-hpa

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