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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 91F91C88E75 for ; Tue, 15 Sep 2026 13:39:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=tZSU09jDCsIk/tpoX25HEUkW1egfskgNv1nvZG1Ds40=; b=0Sie+ZbiE5NI5iEH5vL7liN902 bHNaY4wm8fiJeQG5UR5KuLT7/rNowKZzaRZGHYzWvLxNUzfK2Jkjl+5WGRIgENzojxyi+4QXQ1Rfc xKtplXvUn/jvSSCo1XJawqLixjRoKXptxp6WXwScH5HBgMQs1qzj/elpm6SL6kyXRgv4XQs2Jqrmg vJ+IfKJBBeSOmVqKFgnljEHGq6xcAXDXZAdptvvxYUDuZ2JzUJfZiHlgMDaB/Em4oTfGz94wJiLah hEXc3uyi7asEayhlWXtwd+Uc8k5nxra372n88DeO01N5IKpEdhpiI0ffhZHPaoQ7euoHAkLOrzWBQ i+3v6n1Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x6TNX-00000006lg8-21gz; Tue, 15 Sep 2026 13:39:19 +0000 Received: from stravinsky.debian.org ([2001:41b8:202:deb::311:108]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1x6TNU-00000006lej-464Z for kexec@lists.infradead.org; Tue, 15 Sep 2026 13:39:18 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=debian.org; s=smtpauto.stravinsky; h=X-Debian-User:In-Reply-To:Content-Transfer-Encoding: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Reply-To:Content-ID:Content-Description; bh=tZSU09jDCsIk/tpoX25HEUkW1egfskgNv1nvZG1Ds40=; b=BANf+DRv0G7ET6nd+Q02kEYT2c vD0Mdmy0esC2oiO1N8yesVKAZLUPkTsnz8o42k+YjQG4Z+8iuYgTcrL0MNA6PbeaKganDKnzH1Y6o dz1s24SikbwO6UvoBwIl5MOsySvfek4zhd34ghQRFqhlMs76eRAiXy7gCoWV3PKofIQOYDmDdmZ+z 8umNKp9aZ7sYSbOGScmRPisgvY7fTzJF4LhfQfgaYtHzp+aE8umHMErYILFzLYv+cC6N8zV0soirE MzgEa0+BS6oIJQ04ge7Wt0Df7pee81AIR4q7tocqaLjyrupAkjIJjTRtDxCT86XCyk5TrACr2je2b QoiL60yw==; Received: from authenticated-user by stravinsky.debian.org with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.96) (envelope-from ) id 1x6TN9-004QnQ-0c; Tue, 15 Sep 2026 13:38:55 +0000 Date: Tue, 15 Sep 2026 06:38:47 -0700 From: Breno Leitao To: Harry Yoo Cc: Ard Biesheuvel , Ilias Apalodimas , Miaohe Lin , Naoya Horiguchi , Andrew Morton , "Kiryl Shutsemau (Meta)" , kexec@lists.infradead.org, David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H . Peter Anvin" , Brendan Jackman , Johannes Weiner , Zi Yan , linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, rmikey@meta.com, riel@surriel.com, kernel-team@meta.com Subject: Re: [PATCH v4 2/5] mm/memory-failure: libstub: install the poisoned-memory EFI table Message-ID: References: <20260909-hwpoison-kho-v4-0-359313564495@debian.org> <20260909-hwpoison-kho-v4-2-359313564495@debian.org> <2c9a7bef-3189-4f78-a6cb-61d2f7afd643@app.fastmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Debian-User: leitao X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260915_063917_020499_3E87B209 X-CRM114-Status: GOOD ( 18.46 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On Tue, Sep 15, 2026 at 02:31:38PM +0100, Harry Yoo wrote: > On Tue, Sep 15, 2026 at 05:39:44AM -0700, Breno Leitao wrote: > > > Also, I wonder if some architectures have a scattered set of pfn > > > ranges so that the span from the start pfn to the end pfn being much > > > larger than the actual physical memory size. > > > > > > If so it might make more sense to have a bitmap for each pfn range. > > > > Agreed, having a ->next in linux_efi_poisoned_memory is a good idea that > > we can lean on depending on whatever problem comes up down the road. > > > > Very good point — let's keep this linux_efi_poisoned_memory chain idea in > > mind for whenever we need to expand it. > > You mean 1) keeping the structure as-is for now (and expand later with > new EFI table version) or 2) adjusting the structure in the future > revision of this patchset? I'd say option (1): keep the structure as it is for now, and only adjust it once/if we actually decide to implement the hot-add use case. That's exactly why I added the "u32 version" field to struct linux_efi_poisoned_memory, so, it can be expanded later. Version 1 (this patchset) covers the common, basic approach. If down the road someone sees value in extending it to other use cases (such as hot-plug), we can bump it to v2 and add a ->next field then. What do you think? Thanks for the review, --breno