From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DE9CF17BED0 for ; Tue, 5 Nov 2024 16:37:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730824662; cv=none; b=K6szgWjx2iiV8oJSUXuI1v+3aqZcHYc7y2R/nPIxjygNaSk0Sao+bbNbLhLAMpPaxyC/ZL3+AZHO2HKxbvCOXiXEtzXoPAF7913FN+XXlUb5zt3m2K6RsTgoJbfojxJjyIp5x5QK/5QG5urOLnYWww8hsIQFyK3U7eGunSyqhS0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730824662; c=relaxed/simple; bh=O/jTTaUwoQh0eUfvuP4Hr0L9fXuPuSkAUXxIh5zxY9w=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=Lw86qIE5AE6h7SrNJz7a2lF3CJx3X27ymo3sWwo4VHhq0IqxIPTQ7DsvjfG/MNI+4tPId8OlITbWplYjMFRMCxt7kZEUAW1cV5w0KMjifTjU+lu49JBuaymnNZeea0EEtYxn7oIXhMDsfG6y4N6Ei4Nu3gNZShI6dj7HD3QBhkk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=XdCuYqmv; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="XdCuYqmv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 66260C4CECF; Tue, 5 Nov 2024 16:37:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1730824661; bh=O/jTTaUwoQh0eUfvuP4Hr0L9fXuPuSkAUXxIh5zxY9w=; h=Subject:To:Cc:From:Date:From; b=XdCuYqmviqUNRG5L3vOHfyymLRc3K6H3dOhuPCoVOQcDDghb9CcFzYkEwN7RPfyMl +xYioW67rkCZJVLLpLc971/Ur4dh7ACAzHN1fZLPWQ4yb4MH200dDHyPFGCbVO0xud gh2hBRaMKSnjfvXyY6uKWNkAvnuiJjoMn8MY5X90= Subject: FAILED: patch "[PATCH] mm: allow set/clear page_type again" failed to apply to 6.11-stable tree To: yuzhao@google.com,akpm@linux-foundation.org,muchun.song@linux.dev,stable@vger.kernel.org,willy@infradead.org Cc: From: Date: Tue, 05 Nov 2024 17:37:24 +0100 Message-ID: <2024110524-runner-gravity-4288@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.11-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.11.y git checkout FETCH_HEAD git cherry-pick -x 9d08ec41a0645283d79a2e642205d488feaceacf # git commit -s git send-email --to '' --in-reply-to '2024110524-runner-gravity-4288@gregkh' --subject-prefix 'PATCH 6.11.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 9d08ec41a0645283d79a2e642205d488feaceacf Mon Sep 17 00:00:00 2001 From: Yu Zhao Date: Sat, 19 Oct 2024 22:22:12 -0600 Subject: [PATCH] mm: allow set/clear page_type again Some page flags (page->flags) were converted to page types (page->page_types). A recent example is PG_hugetlb. >From the exclusive writer's perspective, e.g., a thread doing __folio_set_hugetlb(), there is a difference between the page flag and type APIs: the former allows the same non-atomic operation to be repeated whereas the latter does not. For example, calling __folio_set_hugetlb() twice triggers VM_BUG_ON_FOLIO(), since the second call expects the type (PG_hugetlb) not to be set previously. Using add_hugetlb_folio() as an example, it calls __folio_set_hugetlb() in the following error-handling path. And when that happens, it triggers the aforementioned VM_BUG_ON_FOLIO(). if (folio_test_hugetlb(folio)) { rc = hugetlb_vmemmap_restore_folio(h, folio); if (rc) { spin_lock_irq(&hugetlb_lock); add_hugetlb_folio(h, folio, false); ... It is possible to make hugeTLB comply with the new requirements from the page type API. However, a straightforward fix would be to just allow the same page type to be set or cleared again inside the API, to avoid any changes to its callers. Link: https://lkml.kernel.org/r/20241020042212.296781-1-yuzhao@google.com Fixes: d99e3140a4d3 ("mm: turn folio_test_hugetlb into a PageType") Signed-off-by: Yu Zhao Cc: Matthew Wilcox (Oracle) Cc: Muchun Song Cc: Signed-off-by: Andrew Morton diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 1b3a76710487..cc839e4365c1 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -975,12 +975,16 @@ static __always_inline bool folio_test_##fname(const struct folio *folio) \ } \ static __always_inline void __folio_set_##fname(struct folio *folio) \ { \ + if (folio_test_##fname(folio)) \ + return; \ VM_BUG_ON_FOLIO(data_race(folio->page.page_type) != UINT_MAX, \ folio); \ folio->page.page_type = (unsigned int)PGTY_##lname << 24; \ } \ static __always_inline void __folio_clear_##fname(struct folio *folio) \ { \ + if (folio->page.page_type == UINT_MAX) \ + return; \ VM_BUG_ON_FOLIO(!folio_test_##fname(folio), folio); \ folio->page.page_type = UINT_MAX; \ } @@ -993,11 +997,15 @@ static __always_inline int Page##uname(const struct page *page) \ } \ static __always_inline void __SetPage##uname(struct page *page) \ { \ + if (Page##uname(page)) \ + return; \ VM_BUG_ON_PAGE(data_race(page->page_type) != UINT_MAX, page); \ page->page_type = (unsigned int)PGTY_##lname << 24; \ } \ static __always_inline void __ClearPage##uname(struct page *page) \ { \ + if (page->page_type == UINT_MAX) \ + return; \ VM_BUG_ON_PAGE(!Page##uname(page), page); \ page->page_type = UINT_MAX; \ }