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=1794064745; b=jqz7g/kZzzkR1ZNrpWBw6DtvBnFe523HhRqRLwGijGpR/kDKJ9dBpNpzQ7zw0UZJ8bLC 7jsYEjBPwZa/XEVR21+VdVL31wo+opTZ6UNZ5Uqx6DBm0K4ZAK2SeGRpUkl5UOl0QlVsc G5gPkfUDL7kb/F2kN7ilsWB5BjKzR9Dap7VhbgeZ8PAOMsB3msydqeWiMgzTOarZT1sLk K0+REAHtZZcXbxTUJfgVvlnaS167eJuoS/NtP5Fp8e3kRf2dr/PUMuAqPvZkfZ/achLxy 860DEzF5QdagOmea0gYx7edwdd1E67wtpVAAANgDjPBP++q1Sc9DMka2KpqCJnxauvQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794064745; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=cFp5w3IiAfY/nj0UwDPXTtXQIPeQ8EC1M8sfu6tXK7k=; b=1m0SQT9L/V1ENiw8cS1U1c0ZyJPAGXfDClF/2898ILP6r/+83Am5941+/trKaiv8RduZ ZDka26pBET4jr+KYY2ZvOm8IdUV4xqFd+fX79zhmKFkuOmowEjbW337LpMqJ0uPim/pUs 9RXUoKeerN36F7TMA01odQu4+l7yw4+W5vDCb4jOUKC+0dWirKF6dq3qL/Tz66ABi1y54 8Sd2l+Qzt4fnwjY4eQZCmlzxrYWChSPdXfXjo/Iv8pUT2jPDU+NXoXOpf9NZenvU6scNx IwO+G46kKs5P5/AfTFewQ6QAWJklgeXdsHtnHIg0ot2BVFnywt2PINJh48AxDsb58bA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=cqdL4kXs; 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 1F5EA606D81C; Sat, 7 Nov 2026 15:19:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=cqdL4kXs Received: by smtp.kernel.org (Postfix) with ESMTPSA id C35341F0089F; Sat, 7 Nov 2026 15:19:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794064745; bh=cFp5w3IiAfY/nj0UwDPXTtXQIPeQ8EC1M8sfu6tXK7k=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=cqdL4kXsyz+gT52Q45IuErDPhtJAWwO45rfa+uNLaAagqhSP90ZotVt3kAq+hxN2V iqdCdTgFdZIvGwFl9XtiB+kRUY/AORz5LgOOXJyWIReqzp5Rbgo31+OrM2eSZFjSDY 4g6luSMlVFxsxA0CFdRROQuE4B2x6J71Q4yt8ln8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Chao Yu , Barry Song , Nanzhe Zhao , Jaegeuk Kim , Sasha Levin Subject: [PATCH 7.3 0720/1257] f2fs: remove mappedtodisk flag usage in mmap write path Date: Sat, 7 Nov 2026 08:50:16 -0500 Message-ID: <20261107134959.147828771@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134939.434104957@linuxfoundation.org> References: <20261107134939.434104957@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nanzhe Zhao [ Upstream commit b3c9843589257631bac18f30655e82d88970688a ] PG_mappedtodisk was inherited from the nobh/buffer-head era. However, f2fs has no buffer heads and the flag is no longer meaningful. The only user of the flag is the "no holes" shortcut in f2fs_vm_page_mkwrite(), which makes mmap write faults skip marking the folio dirty. Moreover, it causes the following race condition with filesystem freezing: CPU0 (write fault) CPU1 (freeze_super) ---- ---- f2fs_vm_page_mkwrite() sb_start_pagefault() /* shortcut: no dirty */ sb_end_pagefault() sb_wait_write(SB_FREEZE_PAGEFAULT) /* no waiter, passes */ sync_filesystem() /* folio not dirty, skipped */ finish_fault() /* PTE writable */ fault_dirty_shared_page() folio_mark_dirty() /* dirty folio on a frozen fs */ It will also skip APP_MAPPED_IO iostat/REQ_TIME updates and post-EOF folio zeroing. Remove this shortcut in f2fs_vm_page_mkwrite() and stop setting it in f2fs_read_single_page(). Reported-by: Chao Yu Link: https://lore.kernel.org/linux-f2fs-devel/496b913c-eb81-4fa8-be72-c6a06a10aba2@kernel.org/ Reviewed-by: Chao Yu Reviewed-by: Barry Song Fixes: fbfa2cc58d53 ("f2fs: add file operations") Cc: stable@vger.kernel.org Signed-off-by: Nanzhe Zhao Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin --- fs/f2fs/data.c | 1 - fs/f2fs/file.c | 6 ------ 2 files changed, 7 deletions(-) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 5a4af37b358d3..c9a1bb07a5b32 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -2260,7 +2260,6 @@ static int f2fs_read_single_page(struct inode *inode, struct fsverity_info *vi, got_it: if ((map->m_flags & F2FS_MAP_MAPPED)) { block_nr = map->m_pblk + block_in_file - map->m_lblk; - folio_set_mappedtodisk(folio); if (!f2fs_is_valid_blkaddr(F2FS_I_SB(inode), block_nr, DATA_GENERIC_ENHANCE_READ)) { diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 5bd908799e7d5..b391ced41edda 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -217,12 +217,6 @@ static vm_fault_t f2fs_vm_page_mkwrite(struct vm_fault *vmf) /* wait for GCed page writeback via META_MAPPING */ f2fs_wait_on_block_writeback(inode, dn.data_blkaddr); - /* - * check to see if the page is mapped already (no holes) - */ - if (folio_test_mappedtodisk(folio)) - goto out_sem; - /* page is wholly or partially inside EOF */ if (((loff_t)(folio->index + 1) << PAGE_SHIFT) > i_size_read(inode)) { -- 2.53.0