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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83978C3A5A0 for ; Mon, 19 Aug 2019 16:25:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5603122CE3 for ; Mon, 19 Aug 2019 16:25:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=soleen.com header.i=@soleen.com header.b="V6Ye+hp2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727659AbfHSQZU (ORCPT ); Mon, 19 Aug 2019 12:25:20 -0400 Received: from mail-ed1-f67.google.com ([209.85.208.67]:40906 "EHLO mail-ed1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726905AbfHSQZU (ORCPT ); Mon, 19 Aug 2019 12:25:20 -0400 Received: by mail-ed1-f67.google.com with SMTP id h8so2225335edv.7 for ; Mon, 19 Aug 2019 09:25:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=FTybdQSbJYXviMaMHMnMLGJOZBBRUnDKBVwSpon3+iQ=; b=V6Ye+hp2Gl1Ax/97+paIXXGQgJ1el9suKrpEMODehYp5ZX9LIhVfYpDR2ESokcsHRS Aaz3p/FE/TRUrMt+RPQ6/lJGgzcI3HJwwQGGz10VNFg3QS8za2uv5R7hlAm4sQDIzvbD sDwE1+rbxFUH1L0rGmmn2OAaKuqDIESg6uehSYO2UG5pe45fYOj2I23wddTYtUzVCZzy r01SGTGDPR8juGpx0lo2cvmPh8F97yyRqb4hvMacpxOunjoc/ryvfLHdcgVmsStgU9zY KKgdk1hu/HOVk0nBmNczKcAHngdnw8qioLsHdDXAqNLoCV5Xng/kc6cOfjjEkbXgerKM kEJA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=FTybdQSbJYXviMaMHMnMLGJOZBBRUnDKBVwSpon3+iQ=; b=jpdB7cuM44j6RA902CHKel6Y6wT4bUycOmaiW0rYvZXt42c2WL83tL5Pg51dGK2HfG bG3Mdi0tmhlgxEh5V6sd040wX+dkcblPMqvIlCxJgnJOUA3X8hl7hiqbTVjzW0MwxgBz mEjdi3B1fH/fvhKsNf34pJPX8n7TepWVznCgMy3FHSY426LidFFeFAPh+uWqSMV1LxQi Xk5OEfxB8knKn9fuAVr2TT7UKAy30axUM3w1EGfVF01FgSlz/JZ3UTn4D4q96tu36OsZ wY6G06Uj49qfhRHlPyOktF4TpdbxOyYwnRKEECoSZjBiH3ybuIwL2J3xk0HTyGVf+hPT 1nMg== X-Gm-Message-State: APjAAAW11ij0CHvJRssumWzrq7uWaJlqJG8vWWPu0vjRB/8CSHzVF4mi lbAekDMYgowHmbvyz/dAWqpCuWvkgSMooYY6c632Lg== X-Google-Smtp-Source: APXvYqx6DaFjnU6QugCtFRq+z73auQsM7avscMrrbc99LuibAhGgZ9NPXOzVtge16aLCOwfiY8fafEF9yfKLFmVJPQk= X-Received: by 2002:aa7:c552:: with SMTP id s18mr13639157edr.0.1566231918418; Mon, 19 Aug 2019 09:25:18 -0700 (PDT) MIME-Version: 1.0 References: <20190817024629.26611-1-pasha.tatashin@soleen.com> <20190817024629.26611-3-pasha.tatashin@soleen.com> <20190819155014.GD9927@lakrids.cambridge.arm.com> In-Reply-To: <20190819155014.GD9927@lakrids.cambridge.arm.com> From: Pavel Tatashin Date: Mon, 19 Aug 2019 12:25:07 -0400 Message-ID: Subject: Re: [PATCH v2 02/14] arm64, hibernate: create_safe_exec_page cleanup To: Mark Rutland Cc: James Morris , Sasha Levin , "Eric W. Biederman" , kexec mailing list , LKML , Jonathan Corbet , Catalin Marinas , will@kernel.org, Linux ARM , Marc Zyngier , James Morse , Vladimir Murzin , Matthias Brugger , Bhupesh Sharma , linux-mm Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Mark, Thank you for your review comments. My replies below: On Mon, Aug 19, 2019 at 11:50 AM Mark Rutland wrote: > > On Fri, Aug 16, 2019 at 10:46:17PM -0400, Pavel Tatashin wrote: > > create_safe_exec_page() is going to be split into two parts in preparation > > of moving page table handling code out of hibernate.c > > > > Remove allocator parameter, and rename dst to page. Also, remove the > > goto's, as we can return directly without cleanups. > > It would be nice if you could do the goto/allocator/rename changes as > separate patches, since it's vastly easier to verify each change in > isolation that way. Sure, I will split these changes into separate patches in the next version of this patch series. > > What's the point of the rename? It's inconsistent with the phys_dst_addr > that you leave as-is, so I'm not sure that's worthwhile. dst_addr, phys_dst_addr VA/PA destination addresses. But, page is a buffer in the current VA space (hence changed to void *), dst looked confusing as it seemed as it was part of the destination addresses. > > > > > Signed-off-by: Pavel Tatashin > > --- > > arch/arm64/kernel/hibernate.c | 60 +++++++++++++++-------------------- > > 1 file changed, 26 insertions(+), 34 deletions(-) > > > > diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c > > index 9341fcc6e809..96b6f8da7e49 100644 > > --- a/arch/arm64/kernel/hibernate.c > > +++ b/arch/arm64/kernel/hibernate.c > > @@ -196,57 +196,51 @@ EXPORT_SYMBOL(arch_hibernation_header_restore); > > */ > > static int create_safe_exec_page(void *src_start, size_t length, > > unsigned long dst_addr, > > - phys_addr_t *phys_dst_addr, > > - void *(*allocator)(gfp_t mask), > > - gfp_t mask) > > + phys_addr_t *phys_dst_addr) > > { > > - int rc = 0; > > + void *page = (void *)get_safe_page(GFP_ATOMIC); > > + pgd_t *trans_table; > > The addition of this trans_table variable wasn't mentioned in the commit > message... > > > + trans_table = (void *)get_safe_page(GFP_ATOMIC); > > + if (!trans_table) > > + return -ENOMEM; > > > > - pgdp = pgd_offset_raw(allocator(mask), dst_addr); > > + pgdp = pgd_offset_raw(trans_table, dst_addr); > > > - write_sysreg(phys_to_ttbr(virt_to_phys(pgdp)), ttbr0_el1); > > + write_sysreg(phys_to_ttbr(virt_to_phys(trans_table)), ttbr0_el1); > > > ... and I guess you're trying to ensure that we program the TTBR with > the correct base address, without the offset of whatever pgd entry we > happen to have plumbed in? > > I think that's a fix, and should come before any other cleanup or > rework. Yes. > > If you can respin that specific change with s/trans_table/pgdir/, that > would make sense to me. I will split this patch into several changes. I will describe trans_table rational in different e-mail. There we will decide what namespace to use. Thank you, Pasha