From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932552Ab0J0Vhu (ORCPT ); Wed, 27 Oct 2010 17:37:50 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:33093 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932495Ab0J0Vhr (ORCPT ); Wed, 27 Oct 2010 17:37:47 -0400 Date: Wed, 27 Oct 2010 22:37:45 +0100 From: Al Viro To: Chris Metcalf Cc: Arnd Bergmann , linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: situation with signals Message-ID: <20101027213745.GI19804@ZenIV.linux.org.uk> References: <20100923221141.GK19804@ZenIV.linux.org.uk> <9lYpY1#WLHA.1516@exchange1.tad.internal.tilera.com> <4CC89352.7020808@tilera.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4CC89352.7020808@tilera.com> User-Agent: Mutt/1.5.20 (2009-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 27, 2010 at 05:02:10PM -0400, Chris Metcalf wrote: > I set aside this thread to look at when I had a minute, and I believe there > is just one of the signal issues present in the tile code. The fix is to > reset regs->fault to something other than the "syscall" fault type when > exiting from do_signal(), so I'll submit that up for 2.6.37 shortly. > > Otherwise I think tile is doing things right, though I admit, the signal > support is pretty deep magic generally. FWIW, I'd do that in handle_signal() when hitting a syscall restart. BTW, is everything in your pt_regs safe to modify? I.e. could bogus values put there by sigreturn lead to something like kernel mode being retained when you return from syscall or interesting flags being set, etc.?