From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from d12nrmr1607.megacenter.de.ibm.com (d12nrmr1607.megacenter.de.ibm.com [9.149.167.49]) by mtagate3.de.ibm.com (8.12.10/8.12.10) with ESMTP id j72GiImp089682 for ; Tue, 2 Aug 2005 16:44:18 GMT Received: from d12av04.megacenter.de.ibm.com (d12av04.megacenter.de.ibm.com [9.149.165.229]) by d12nrmr1607.megacenter.de.ibm.com (8.12.10/NCO/VERS6.7) with ESMTP id j72GiIeZ162926 for ; Tue, 2 Aug 2005 18:44:18 +0200 Received: from d12av04.megacenter.de.ibm.com (loopback [127.0.0.1]) by d12av04.megacenter.de.ibm.com (8.12.11/8.13.3) with ESMTP id j72GiHDt008631 for ; Tue, 2 Aug 2005 18:44:18 +0200 In-Reply-To: Subject: Re: [patch 2.6.13-rc4] fix get_user_pages bug Message-ID: From: Martin Schwidefsky Date: Tue, 2 Aug 2005 18:44:18 +0200 MIME-Version: 1.0 Content-type: text/plain; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Linus Torvalds Cc: Andrew Morton , Robin Holt , Hugh Dickins , linux-kernel , linux-mm@kvack.org, Ingo Molnar , Nick Piggin , Roland McGrath List-ID: Linus Torvalds wrote on 08/02/2005 05:30:37 PM: > > With the additional !pte_write(pte) check (and if I haven't overlooked > > something which is not unlikely) s390 should work fine even without the > > software-dirty bit hack. > > No it won't. It will just loop forever in a tight loop if somebody tries > to put a breakpoint on a read-only location. Yes, I have realized that as well nowe after staring at the code a little bit longer. That maybe_mkwrite is really tricky. > On the other hand, this being s390, maybe nobody cares? Some will care. At least I do. I've tested the latest git with gdb and it will indeed loop forever if I try to write to a read-only vma. blue skies, Martin Martin Schwidefsky Linux for zSeries Development & Services IBM Deutschland Entwicklung GmbH -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org