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Date: Fri, 20 Sep 2002 23:19:46 -0700
From: Richard Henderson <rth@twiddle.net>
To: george anzinger <george@mvista.com>
Cc: Mikael Pettersson <mikpe@csd.uu.se>, Daniel Jacobowitz <dan@debian.org>,
       Brian Gerst <bgerst@didntduck.org>,
       Petr Vandrovec <VANDROVE@vc.cvut.cz>,
       "Richard B. Johnson" <root@chaos.analogic.com>,
       dvorak <dvorak@xs4all.nl>, linux-kernel@vger.kernel.org
Subject: Re: Syscall changes registers beyond %eax, on linux-i386
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In-Reply-To: <3D8ADD05.999E4A5C@mvista.com>; from george@mvista.com on Fri, Sep 20, 2002 at 01:32:05AM -0700
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On Fri, Sep 20, 2002 at 01:32:05AM -0700, george anzinger wrote:
> So, is there a problem?  Yes, neither the call stub macros
> in asm/unistd.h nor those in glibc bother to list the used
> registers beyond the third ":".

No, this is not the real problem.  The real problem is that if
the program receives a signal during a system call, the kernel
will return all the way up to entry.S, deliver the signal and
then restart the syscall.

Except the syscall will restart with the corrupted registers.

Hilarity ensues.



r~