From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 81285606A33C for ; Tue, 3 Nov 2026 09:49:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=GV++1Djw Received: by kanga.kvack.org (Postfix) id ACFAA6B05B2; Tue, 3 Nov 2026 04:49:04 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A53296B05B3; Tue, 3 Nov 2026 04:49:04 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 969A96B05B4; Tue, 3 Nov 2026 04:49:04 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 71EA56B05B2 for ; Tue, 3 Nov 2026 04:49:04 -0500 (EST) Received: from smtpin11.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay08.hostedemail.com (Postfix) with ESMTP id AA6D7140339 for ; Tue, 3 Nov 2026 09:49:03 +0000 (UTC) X-FDA: 85393334166.11.FE10EBA Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf15.hostedemail.com (Postfix) with ESMTP id 0F55EA0003 for ; Tue, 3 Nov 2026 09:49:01 +0000 (UTC) Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=GV++1Djw; spf=pass (imf15.hostedemail.com: domain of rppt@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1793699342; b=cOCzVdt3h3VPy/LCtHGWe31Xnuuo3c4EOpuhDWiEyDneIj1trlIFR7YvzunPwSotsbV8C2 1L5ExiWVaaYzs1948NFrt8/LCiTrpPkTCE44lSYkskLDRm1Y7XWkmMmUo4QzxikhEYUqtq eqn2Zi3kIo7gLtYKrTRiPs5/eYCTsaQ= ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=GV++1Djw; spf=pass (imf15.hostedemail.com: domain of rppt@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1793699342; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=cgwH7+eb4DO1f1hZBo5/HU3TXgqaVoeCZLybivmvUJo=; b=BSv4gtUWw6F8HKdjyaRKb+S3MV8WcXpp/pWnTH2/tF/dOaz15B6lkQQvpMA+L5ZiE1bj4M eGFzjc7VhEt7AM5MMnq9Qegi51kBL37epjEYQ8jB/P/4JXbQCTSRd6DJZKyEbSDZryWwxR OzpfdMelpTOceyjM9YZbbfObXW3/Nu0= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 9BC37605CB; Tue, 3 Nov 2026 09:49:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A74261F000C1; Tue, 3 Nov 2026 09:48:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793699340; bh=cgwH7+eb4DO1f1hZBo5/HU3TXgqaVoeCZLybivmvUJo=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=GV++1DjwxRqBZTgtqKQjH8FDRWWNjQ0UExyz4D4wPRG6CXHgHqlai8IgSZ5/B9AVO fyr6sYpt+ugUguBnTwfa9EONvXK3lfiCOo8fFL2gesEHkb4WUZGfvT6fCfMJNsI31Z Vw/EI3JAg4jrRuPcmYktzzSqUrEL7bUe5ETL5f1c0mbZHI+qxZizlD4FmPKJbOX8x8 UcFo7Cvy49IASUxO9wd2cXytT8/WMCHJsvvJP/mjOG1ZnH5zkongCwU5jFXzRP2W/i UHtO33zaLptW2P5/6tQLOOQzYQ1+oU9XS++2xZHKEc1aCasgMoti+lnda5b6BltK8l casrwkwEvaa2g== Date: Tue, 3 Nov 2026 11:48:43 +0200 From: Mike Rapoport To: Breno Leitao Cc: Ard Biesheuvel , Ilias Apalodimas , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Miaohe Lin , Naoya Horiguchi , Oscar Salvador , Greg Kroah-Hartman , "Rafael J. Wysocki" , Danilo Krummrich , Catalin Marinas , Will Deacon , Mark Rutland , kas@kernel.org, kexec@lists.infradead.org, Brendan Jackman , Johannes Weiner , Zi Yan , shakeel.butt@linux.dev, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-cxl@vger.kernel.org, driver-core@lists.linux.dev, linux-arm-kernel@lists.infradead.org, rmikey@meta.com, riel@surriel.com, harry@kernel.org, kernel-team@meta.com Subject: Re: [PATCH v6 3/7] mm/memory-failure: add hwpoison_boot_page() to flag an inherited frame Message-ID: References: <20261016-hwpoison-kho-v6-0-f304255147da@debian.org> <20261016-hwpoison-kho-v6-3-f304255147da@debian.org> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261016-hwpoison-kho-v6-3-f304255147da@debian.org> X-Stat-Signature: h3qfte5aw1m4smsiwks4f7dexx19qfr6 X-Rspamd-Queue-Id: 0F55EA0003 X-Rspam-User: X-Rspamd-Server: rspam11 X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS autolearn=unavailable autolearn_force=no version=4.0.1 X-HE-Tag: 1793699341-261180 X-HE-Meta: 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 sBkZo7DU wXV1O4qw+LrzdZmvnnUMJD4LTUrw+O33J5/UpMzYsksG2BcCvAQXUStyXHWFIzO9DcU5E4VA/7s5h8dJSQDZ4gM74JFhHBLYvz6ZKPKNhI6d2McmxEnMr5a/9gEj8SdXIFfqhXjuKj//mdnoWLd2ZjWWTMaVyA+nZMgbMmAm71Gbz7dhuC27tglyBtkpASBnmA10C1dEoSodd7eMr5cySQpS1fBx6i0m/iODZ0OX9/646VU8D8yLHqp0PWK+XmmD5d+ufa+53kInUnEh6FDr1A9ysB147B7E1uYnS+sRu6zB0tX+tgf4QoWLTp/+mHLdhzfftINJb5a3UpeEre8DhEmB8n56Mad24hFBvrVBF8KI8oX7OPQasT6g5YWaleyxMR45XvqTv5jokwG4bLXQBEB/euw== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Fri, Oct 16, 2026 at 05:15:43AM -0700, Breno Leitao wrote: > A kernel that kexecs inherits the frames its predecessor found > hardware-poisoned. It has to carry them as PG_hwpoison in its own memmap, > so that everything that already understands the flag covers them, > including the kexec segment placement check. > > Add a helper that sets the flag and counts the frame in > num_poisoned_pages. It runs while the memmap is initialised, before > memory_dev_init() has run. memblk_nr_poison_inc() divides by > sections_per_block, which memory_dev_init() sets, so the helper > increments num_poisoned_pages itself instead of calling > num_poisoned_pages_inc(). > > An inherited frame is a hardware failure like any other, so the helper > sets hw_memory_failure. Without it, unpoison_memory() accepts the frame, > clears the flag and drops the last reference, which frees a frame that > is still bad. > > The helper also counts the frame as managed, as a frame that fails at > run time stays counted. Memory offlining subtracts every frame of the > block that is not PageOffline, so a frame that was never counted leaves > the managed page count too low after an offline. > > The per-node memory failure statistics are not updated. This kernel > handled no failure, it only inherited one. > > Signed-off-by: Breno Leitao > --- > mm/internal.h | 5 +++++ > mm/memory-failure.c | 8 ++++++++ > 2 files changed, 13 insertions(+) > > diff --git a/mm/internal.h b/mm/internal.h > index da14c56fb24e11..4bd3bbce86e0ad 100644 > --- a/mm/internal.h > +++ b/mm/internal.h > @@ -1169,6 +1169,7 @@ void SetPageHWPoisonTakenOff(struct page *page); > void ClearPageHWPoisonTakenOff(struct page *page); > bool take_page_off_buddy(struct page *page); > bool put_page_back_buddy(struct page *page); > +void __init hwpoison_boot_page(struct page *page); > struct task_struct *task_early_kill(struct task_struct *tsk, int force_early); > void add_to_kill_ksm(struct task_struct *tsk, const struct page *p, > struct vm_area_struct *vma, struct list_head *to_kill, > @@ -1181,6 +1182,10 @@ static inline int unmap_poisoned_folio(struct folio *folio, unsigned long pfn, b > { > return -EBUSY; > } > + > +static inline void hwpoison_boot_page(struct page *page) > +{ > +} > #endif We've been splitting internal.h to smaller headers, maybe it's time to add "memory-faulure.h"? > extern unsigned long __must_check vm_mmap_pgoff(struct file *, unsigned long, > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index a2ca8df501caee..d0d6b184ee469f 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -96,6 +96,14 @@ void num_poisoned_pages_sub(unsigned long pfn, long i) > memblk_nr_poison_sub(pfn, i); > } > > +void __init hwpoison_boot_page(struct page *page) > +{ > + SetPageHWPoison(page); > + atomic_long_inc(&num_poisoned_pages); > + hw_memory_failure = true; > + adjust_managed_page_count(page, 1); > +} > + > /* > * Return the first or the last hardware-poisoned online page in [start, > * start + size), or PHYS_ADDR_MAX if the range is clean. > > -- > 2.53.0-Meta > -- Sincerely yours, Mike.