Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754377AbbGJLZs (ORCPT ); Fri, 10 Jul 2015 07:25:48 -0400 Received: from pandora.arm.linux.org.uk ([78.32.30.218]:60927 "EHLO pandora.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753672AbbGJLZl (ORCPT ); Fri, 10 Jul 2015 07:25:41 -0400 Date: Fri, 10 Jul 2015 12:25:22 +0100 From: Russell King - ARM Linux To: Stefan Agner Cc: Rob Herring , Laura Abbott , Kees Cook , Arnd Bergmann , Ard Biesheuvel , linux-kernel@vger.kernel.org, Mark Salter , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v3] ARM: early fixmap support for earlycon Message-ID: <20150710112522.GR7557@n2100.arm.linux.org.uk> References: <1433593888-7142-1-git-send-email-stefan@agner.ch> <20150606124800.GR7557@n2100.arm.linux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150606124800.GR7557@n2100.arm.linux.org.uk> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1226 Lines: 28 On Sat, Jun 06, 2015 at 01:48:00PM +0100, Russell King - ARM Linux wrote: > On Sat, Jun 06, 2015 at 02:31:28PM +0200, Stefan Agner wrote: > > @@ -1231,7 +1272,7 @@ static void __init devicemaps_init(const struct machine_desc *mdesc) > > > > early_trap_init(vectors); > > > > - for (addr = VMALLOC_START; addr; addr += PMD_SIZE) > > + for (addr = VMALLOC_START; addr < FIXADDR_START; addr += PMD_SIZE) > > pmd_clear(pmd_off_k(addr)); > > You introduce a bug here - we no logner clear the very top entry of the > page tables, which means it could contain anything - and means that the > subsequent creation of the L2 table in early_pte_alloc() can fail. You trimmed my reply hard, and seemingly ignored this; the v4 patch contains exactly the same code here, and therefore continues to leave the top of the page table uninitialised. Not applying the v4 patch, sorry. -- FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up according to speedtest.net. -- 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/