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 59C48189F5B for ; Mon, 15 Jul 2024 11:37:01 +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=1721043421; cv=none; b=qBSAokF1o+RVf6YkPPQvNw+CVsWuRUexEwH9URU+BtI+5nUMoTa5kJOKiS9cKziXvd8D+GSbDTtisMr58E355Uvj2gUk17rvbClIK9uljp++HbJ9Sdj/A4LWUvVDhLoGOj6RFzBnqizJkkivLDCrLGSm6x8s4mYE4h2mbzPAqiQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721043421; c=relaxed/simple; bh=PUEr48ziNf75ANzMTwbRYlW34XKC2VVG9Hz6u8ehJys=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=PWO9xk6bEO6xC6uPjNJmqNxY73jcpWIZslAaLFb5ePJBlNRST9wrjWa7NOSeh9pzVrDJR1myxJAbMP56dcEwa+aC6j710/C70opZuyQjyaHO1ZwmXS9Y3K0wefWANYaVZzDUW5EpmxEz9NMnfAK+DvihzZm/dNgZa2c5VcdLMVc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=HZjT8w2I; 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="HZjT8w2I" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CE584C32782; Mon, 15 Jul 2024 11:37:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1721043421; bh=PUEr48ziNf75ANzMTwbRYlW34XKC2VVG9Hz6u8ehJys=; h=Subject:To:Cc:From:Date:From; b=HZjT8w2IyFwrZ0kMhfgS3RXFE7KYZJLBMCTViwF8L84l+4sXoMkk/N1gc9lm9Bxi2 B8ysQbADIUrAwxptNbgBGLBntgld4QJSaho7n1ldy5waPHYlICeQCqzKDLQlxSc4E8 JeiXKT7Ftj0lVN03NRJehEZm6ymBga1Fc/zd2xIk= Subject: FAILED: patch "[PATCH] mm/hugetlb: fix potential race in" failed to apply to 6.9-stable tree To: linmiaohe@huawei.com,akpm@linux-foundation.org,muchun.song@linux.dev,osalvador@suse.de,stable@vger.kernel.org Cc: From: Date: Mon, 15 Jul 2024 13:36:58 +0200 Message-ID: <2024071558-unbundle-resize-a6d4@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 6.9-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-6.9.y git checkout FETCH_HEAD git cherry-pick -x 5596d9e8b553dacb0ac34bcf873cbbfb16c3ba3e # git commit -s git send-email --to '' --in-reply-to '2024071558-unbundle-resize-a6d4@gregkh' --subject-prefix 'PATCH 6.9.y' HEAD^.. Possible dependencies: 5596d9e8b553 ("mm/hugetlb: fix potential race in __update_and_free_hugetlb_folio()") bd225530a4c7 ("mm/hugetlb_vmemmap: fix race with speculative PFN walkers") 51718e25c53f ("mm: convert arch_clear_hugepage_flags to take a folio") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 5596d9e8b553dacb0ac34bcf873cbbfb16c3ba3e Mon Sep 17 00:00:00 2001 From: Miaohe Lin Date: Mon, 8 Jul 2024 10:51:27 +0800 Subject: [PATCH] mm/hugetlb: fix potential race in __update_and_free_hugetlb_folio() There is a potential race between __update_and_free_hugetlb_folio() and try_memory_failure_hugetlb(): CPU1 CPU2 __update_and_free_hugetlb_folio try_memory_failure_hugetlb folio_test_hugetlb -- It's still hugetlb folio. folio_clear_hugetlb_hwpoison spin_lock_irq(&hugetlb_lock); __get_huge_page_for_hwpoison folio_set_hugetlb_hwpoison spin_unlock_irq(&hugetlb_lock); spin_lock_irq(&hugetlb_lock); __folio_clear_hugetlb(folio); -- Hugetlb flag is cleared but too late. spin_unlock_irq(&hugetlb_lock); When the above race occurs, raw error page info will be leaked. Even worse, raw error pages won't have hwpoisoned flag set and hit pcplists/buddy. Fix this issue by deferring folio_clear_hugetlb_hwpoison() until __folio_clear_hugetlb() is done. So all raw error pages will have hwpoisoned flag set. Link: https://lkml.kernel.org/r/20240708025127.107713-1-linmiaohe@huawei.com Fixes: 32c877191e02 ("hugetlb: do not clear hugetlb dtor until allocating vmemmap") Signed-off-by: Miaohe Lin Acked-by: Muchun Song Reviewed-by: Oscar Salvador Cc: Signed-off-by: Andrew Morton diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 2afb70171b76..fe44324d6383 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1725,13 +1725,6 @@ static void __update_and_free_hugetlb_folio(struct hstate *h, return; } - /* - * Move PageHWPoison flag from head page to the raw error pages, - * which makes any healthy subpages reusable. - */ - if (unlikely(folio_test_hwpoison(folio))) - folio_clear_hugetlb_hwpoison(folio); - /* * If vmemmap pages were allocated above, then we need to clear the * hugetlb flag under the hugetlb lock. @@ -1742,6 +1735,13 @@ static void __update_and_free_hugetlb_folio(struct hstate *h, spin_unlock_irq(&hugetlb_lock); } + /* + * Move PageHWPoison flag from head page to the raw error pages, + * which makes any healthy subpages reusable. + */ + if (unlikely(folio_test_hwpoison(folio))) + folio_clear_hugetlb_hwpoison(folio); + folio_ref_unfreeze(folio, 1); /*