Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753458AbbGaXHO (ORCPT ); Fri, 31 Jul 2015 19:07:14 -0400 Received: from mail.kmu-office.ch ([178.209.48.109]:46742 "EHLO mail.kmu-office.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752952AbbGaXHK (ORCPT ); Fri, 31 Jul 2015 19:07:10 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Date: Thu, 30 Jul 2015 23:02:38 +0200 From: Stefan Agner To: linux@arm.linux.org.uk Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Mark Salter , Kees Cook , Laura Abbott , Arnd Bergmann , Ard Biesheuvel , Rob Herring Subject: Re: [PATCH v4] ARM: early fixmap support for earlycon In-Reply-To: <1434491507-6208-1-git-send-email-stefan@agner.ch> References: <1434491507-6208-1-git-send-email-stefan@agner.ch> Message-ID: <00498073e34373292dd053cdb700ff25@agner.ch> User-Agent: Roundcube Webmail/1.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1247 Lines: 35 On 2015-06-16 23:51, Stefan Agner wrote: > static void __init devicemaps_init(const struct machine_desc *mdesc) > { > @@ -1231,7 +1272,10 @@ static void __init devicemaps_init(const struct > machine_desc *mdesc) > > early_trap_init(vectors); > > - for (addr = VMALLOC_START; addr; addr += PMD_SIZE) > + /* > + * Clear page table except top pmd used by early fixmaps > + */ > + for (addr = VMALLOC_START; addr < (FIXADDR_TOP & PMD_MASK); addr += PMD_SIZE) > pmd_clear(pmd_off_k(addr)); > Hi Russel, Checked this again, v4 does the right thing: FIXADDR_TOP (0xffeff000) & PMD_MASK (0xffe00000) gives us the address of the top PMD (0xFFE00000). We don't clear that since that is taken care of by early fixmap support (early_fixmap_shutdown). v3 used FIXADDR_START, which also left out the second to top PMD. The 3MiB of fixmap spawns two PMD's however only the top PMD is handled by early fixmap. Hence this was wrong in v3, but is fixed in v4. Can you reconsider this patch? -- Stefan -- 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/