Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750717AbXBKQez (ORCPT ); Sun, 11 Feb 2007 11:34:55 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750718AbXBKQez (ORCPT ); Sun, 11 Feb 2007 11:34:55 -0500 Received: from x35.xmailserver.org ([64.71.152.41]:3697 "EHLO x35.xmailserver.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750717AbXBKQey (ORCPT ); Sun, 11 Feb 2007 11:34:54 -0500 X-AuthUser: davidel@xmailserver.org Date: Sun, 11 Feb 2007 08:34:51 -0800 (PST) From: Davide Libenzi X-X-Sender: davide@alien.or.mcafeemobile.com To: Heiko Carstens cc: Ralf Baechle , David Woodhouse , linux-mips@linux-mips.org, Andrew Morton , Alexey Dobriyan , Linux Kernel Mailing List , Ulrich Drepper Subject: Re: -mm merge plans for 2.6.21 In-Reply-To: <20070211161446.GB11547@osiris.ibm.com> Message-ID: References: <20070208150710.1324f6b4.akpm@linux-foundation.org> <1171042535.29713.96.camel@pmac.infradead.org> <20070209134516.2367a7aa.akpm@linux-foundation.org> <1171058342.29713.136.camel@pmac.infradead.org> <20070210102205.GB8145@osiris.boeblingen.de.ibm.com> <1171103527.29713.228.camel@pmac.infradead.org> <20070210213447.GB9116@linux-mips.org> <20070211161446.GB11547@osiris.ibm.com> X-GPG-FINGRPRINT: CFAE 5BEE FD36 F65E E640 56FE 0974 BF23 270F 474E X-GPG-PUBLIC_KEY: http://www.xmailserver.org/davidel.asc MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1838 Lines: 45 On Sun, 11 Feb 2007, Heiko Carstens wrote: > On Sat, Feb 10, 2007 at 09:34:47PM +0000, Ralf Baechle wrote: > > On Sat, Feb 10, 2007 at 10:32:07AM +0000, David Woodhouse wrote: > > > > > On Sat, 2007-02-10 at 11:22 +0100, Heiko Carstens wrote: > > > > Which remembers me that I think that MIPS is using the non-compat version > > > > of sys_epoll_pwait for compat syscalls. But maybe MIPS doesn't need a compat > > > > syscall for some reason. Dunno. > > > > > > It's OK as long as the 64-bit kernel, N32 and O32 userspace all agree > > > there there's 32 bits of padding between the fields of this structure: > > > > > > struct epoll_event { > > > __u32 events; > > > __u64 data; > > > }; > > > > > > I suspect it's a fairly safe bet that N32 userspace agrees; if the O32 > > > ABI is different then it would need the compat syscall. > > > > That is correct - and apparently for all ABIs because I wasn't able to find > > a compat_sys_epoll_pwait at all. > > Hmm.. so you don't need to do some fancy compat conversion for the sigset_t > that gets passed? Why is that? I don't get it... The compat_sys_epoll_pwait function has two sources of compat. One is the sigset_t and the other one is the struct epoll_event. The sigset_t compat is always needed, while the struct epoll_event may be needed. The code of (upcoming) compat_sys_epoll_pwait takes care of both, with a smart compile-time check to wire sys_epoll_wait or compat_sys_epoll_wait, depending on the need of the struct epoll_event compat handling. So yes, compat_sys_epoll_pwait is needed. - Davide - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/