From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 44EBFC43334 for ; Fri, 22 Jul 2022 14:16:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235229AbiGVOQk (ORCPT ); Fri, 22 Jul 2022 10:16:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233115AbiGVOQj (ORCPT ); Fri, 22 Jul 2022 10:16:39 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AF4F5A026A for ; Fri, 22 Jul 2022 07:16:38 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 3D6F962096 for ; Fri, 22 Jul 2022 14:16:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8B7B1C341C6; Fri, 22 Jul 2022 14:16:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1658499397; bh=qPci77WK/98/z0Cyg/1FZengXU7A1Tr9GDGL2oMHA0M=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=VQuQTeCEljHzEjJXz4qGxwKYrcgTdErLguIV6/4HKkpKoeCVIjSS0uv4pb2wvi1IK bHat0KgKoTn8ZmQA0QM7Xtc58ZnG+QHHbVxlaalI324Z8MM58OSogUO9xixlT/pYqY WTUY5o2m2IWAhK7ubI5zNin0z5/lmMlSXnCPIR4ekta45lejAK3soV79PlOezX3wxa w8hcjECHGr2MIJJom2Jlg7tTyRVHYA3ub9R2auvu0D38tWkp22THyNfc/R1OtypSkJ wxf2gaxDERD9CxJkocrr0j6/U3YJmhiwDH+AVIkutn7mSUfh3VITPIpoxvL3+D7+28 LLc/b2d+pdf/w== Received: from sofa.misterjones.org ([185.219.108.64] helo=why.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1oEtSF-009MCL-0a; Fri, 22 Jul 2022 15:16:35 +0100 Date: Fri, 22 Jul 2022 15:16:34 +0100 Message-ID: <87leslxmf1.wl-maz@kernel.org> From: Marc Zyngier To: Peter Collingbourne Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, Cornelia Huck , Catalin Marinas , Will Deacon , Evgenii Stepanov , kvm@vger.kernel.org, Steven Price , Vincenzo Frascino Subject: Re: [PATCH v2 3/7] mm: Add PG_arch_3 page flag In-Reply-To: <20220722015034.809663-4-pcc@google.com> References: <20220722015034.809663-1-pcc@google.com> <20220722015034.809663-4-pcc@google.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/27.1 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: pcc@google.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, cohuck@redhat.com, catalin.marinas@arm.com, will@kernel.org, eugenis@google.com, kvm@vger.kernel.org, steven.price@arm.com, vincenzo.frascino@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Fri, 22 Jul 2022 02:50:29 +0100, Peter Collingbourne wrote: > > As with PG_arch_2, this flag is only allowed on 64-bit architectures due > to the shortage of bits available. It will be used by the arm64 MTE code > in subsequent patches. > > Signed-off-by: Peter Collingbourne > Cc: Will Deacon > Cc: Marc Zyngier > Cc: Steven Price > [catalin.marinas@arm.com: added flag preserving in __split_huge_page_tail()] > Signed-off-by: Catalin Marinas > --- > fs/proc/page.c | 1 + > include/linux/page-flags.h | 1 + > include/trace/events/mmflags.h | 7 ++++--- > mm/huge_memory.c | 1 + > 4 files changed, 7 insertions(+), 3 deletions(-) > > diff --git a/fs/proc/page.c b/fs/proc/page.c > index a2873a617ae8..438b8aa7249d 100644 > --- a/fs/proc/page.c > +++ b/fs/proc/page.c > @@ -220,6 +220,7 @@ u64 stable_page_flags(struct page *page) > u |= kpf_copy_bit(k, KPF_ARCH, PG_arch_1); > #ifdef CONFIG_64BIT > u |= kpf_copy_bit(k, KPF_ARCH_2, PG_arch_2); > + u |= kpf_copy_bit(k, KPF_ARCH_2, PG_arch_3); Are PG_arch_2 and PG_arch_3 supposed to share the same user bit in /proc/kpageflags? This seems odd. M. -- Without deviation from the norm, progress is not possible.