From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793156804; b=RkJdyh2tLr/Ry6MDzPv0eGPBKhzun0xaTKzD/7zC6AdDaOCdo7jlXNCAIq4aCkmDcocc uX1ZFSz79mVBmSe51S/Kp6za/1PxCfZAprslX+u8AaAbUgcZDSoEiWjzI5eXZtfIU/7Ys eam8jHZ2m5s2Kxr5R28w9Y2RAyvRd3x2psIpDwY8sm6sJp16gjK+Fdh/Rs24hKYL9alNg 9qqw7n0ksHMV7+9vzvcGbucQh3TDMeWJHFYa4FdSUWS4wr4pV7bMtUWzPqaap6uTRtaau xpstmOnt7EucCLGYo44NwLFzOYWSVbZaxBaphuI2eAc7EXyE26YqotkAwDdzOe35Y3A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793156804; h=Received:DKIM-Signature:Date:To:From:Subject:Message-Id; bh=DBdwUfsBdMvdd05UGfYk/F/suUI6kx3MJW4W4fl1LvM=; b=iBS+2AbzLStd/pPrNYWjJ8k2U76A6+dXLTxB6bDnCrKqIpcXVAe3OHOZT7Kin0rli7JN gxTyhxNoNPUgcPvE5v5hU3zY4yFbQ86wSIsAKvHjANhb7GOBAHtxn1SzT7wLIWnRQjDLV 0VXqB0mTYv9yMnLnPeB7wRsQohqVJ6NGVaFxtkIG61UoAxw20tecckTIy1789QSIO0Map T62V9HlFFbcgZohBMhcwJUOeKNQ9a8tZzClj0Qy3ydLJBAyVLwIHCimEIg06MRTPr/iM2 16MXe4j6slQgtHR8E3ZVykoX7e9SSZ3wbV+hUok2kIacNTvFPC+2Z34NRVVYl3Po63g== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linux-foundation.org header.i=@linux-foundation.org header.a=rsa-sha256 header.s=korg header.b=uu86d0hq; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 549BB606A31A for ; Wed, 28 Oct 2026 03:06:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux-foundation.org header.i=@linux-foundation.org header.a=rsa-sha256 header.s=korg header.b=uu86d0hq Received: by smtp.kernel.org (Postfix) with ESMTPSA id BFB321F01828; Wed, 28 Oct 2026 03:06:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1793156803; bh=DBdwUfsBdMvdd05UGfYk/F/suUI6kx3MJW4W4fl1LvM=; h=Date:To:From:Subject; b=uu86d0hqGKcPu0lKJsl8ay2gyday69NI/bQleZIYXmT1tORik9rJm7m+7rn+n+WWy /SAtNugJlFZBh8wxcdU5gCX8koqvw+2v0ZUG1r8+8slk20YjRWfIP4CG9DhthLeNuS WcbepJAR+m/yOYsLDubLcFA3xNHzcmSPhh4yh2AQ= Date: Tue, 27 Oct 2026 20:06:43 -0700 To: mm-commits@vger.kernel.org,josef@toxicpanda.com,akpm@linux-foundation.org From: Andrew Morton Subject: [to-be-updated] mm-page_isolation-do-not-take-slab-pages-for-free.patch removed from -mm tree Message-Id: <20261028030643.BFB321F01828@smtp.kernel.org> X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list The quilt patch titled Subject: mm: page_isolation: do not take slab pages for free has been removed from the -mm tree. Its filename was mm-page_isolation-do-not-take-slab-pages-for-free.patch This patch was dropped because an updated version will be issued ------------------------------------------------------ From: Josef Bacik Subject: mm: page_isolation: do not take slab pages for free Date: Tue, 27 Oct 2026 16:46:33 +0100 page_is_unmovable() regards a page with a reference count of zero as free or about to be freed. Since slab allocates frozen pages, they will be wrongly considered to be freed if order 0 (higher-order compound pages are caught earlier). If such slabs are the only unmovable pages of a memory block, memory offlining now isolates the block, this can lead to offline_pages() looping without progress. Thus detect the slab pages as removable to return -EBUSY, as would happen before commit 9aec2fb0fd5e ("slab: allocate frozen pages"). Link: https://lore.kernel.org/20261027-pgalloc-ai-hotfixes-v1-7-9c7d1aca801e@kernel.org Fixes: 9aec2fb0fd5e ("slab: allocate frozen pages") Signed-off-by: Josef Bacik Signed-off-by: Vlastimil Babka (SUSE) Signed-off-by: David Hildenbrand (Arm) Signed-off-by: Andrew Morton Assisted-by: LLM Cc: Zi Yan Cc: Shakeel Butt Cc: Mike Rapoport Cc: Oscar Salvador Cc: Matthew Wilcox (Oracle) Cc: Suren Baghdasaryan Cc: Michal Hocko Cc: Brendan Jackman Cc: Johannes Weiner Cc: "Gregory Price (Meta)" --- mm/memory_hotplug.c | 7 +++++++ mm/page_isolation.c | 7 +++++++ 2 files changed, 14 insertions(+) --- a/mm/memory_hotplug.c~mm-page_isolation-do-not-take-slab-pages-for-free +++ a/mm/memory_hotplug.c @@ -1847,6 +1847,13 @@ static int scan_movable_pages(unsigned l if (PageOffline(page) && page_count(page)) return -EBUSY; + /* + * A page that was allocated, but was not a slab page yet, when + * its pageblock was isolated. + */ + if (PageSlab(page)) + return -EBUSY; + folio = page_folio(page); if (!folio_test_hugetlb(folio)) continue; --- a/mm/page_isolation.c~mm-page_isolation-do-not-take-slab-pages-for-free +++ a/mm/page_isolation.c @@ -75,6 +75,13 @@ bool page_is_unmovable(struct zone *zone } /* + * Slab pages are frozen: do not take their reference count of zero + * for that of a free page. + */ + if (PageSlab(page)) + return true; + + /* * We can't use page_count without pin a page * because another CPU can free compound page. * This check already skips compound tails of THP _ Patches currently in -mm which might be from josef@toxicpanda.com are mm-memory_hotplug-resize-zones-under-their-seqlock.patch mm-page_alloc-check-pageblock-pfns-under-span-seqlock.patch mm-filemap-dont-lose-a-folio-lock-wakeup-to-a-signal.patch