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=1794244021; b=gKADz8zBQs4uq6jvT4h0qQXBQpEM61agWJ4UapJoONpZjLmKPaWrEixBJQDhcSF4KN+F EI7+ziAOY+nMnG366AEKuJCsqPuNqYVD7WFKevWJmHK1XmNZUDDoWnUT7p264qjGYCe7Z Ta7K8HLjWq3Ba1KdwsY1Dgxi6fgRm4ekRzcxJHJHt3dG37HP4zw7AYx6rLrAl/7t8SjWH jvzTDHABgbnntnmd9hh9QGWrQLmpPN/C2xdus9f6rp/O6TvyL1luZqzc5RMYJLqTNAsfd gUCBklGZPWGf0Aro1C5VkcZ0jnUxg/j1WHX7R9J0ANXrofjGwZ9KDVPdLNSIrBCK54w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794244021; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=o0XLFTdWrN2sO/ZXmho8UhMLZmwb5fSxJsxm1JO1NnQ=; b=idSNGAqfOKEXyZv5g7nVfrP/AlVvJjxsPxVyFyvs1pyTZdEGEXef2KI2mHpVB+0TnJe+ 7c0JLdcXnjNMDk9n4XI3A1tIs9PZbeSLDE6EiTRVV51ccqALxwVX6AThxhkGcnKp+GeFQ vfFfm7CTzbc9t1GnzWz6QE4YbFQ+FZGdp76qpiqKmbBJFQvyDYAUpNo6PeMz+TBMtHvRc 7jOjwUsnhEJmvcNZWk4JQzDVJakP/KiohRT3mu9P+wXM6nPPubYg+kkEINL0S7VAxehCy qvjFmp4BeBej+Oib1oIYRjNLI7OPCTuoO7cQh7PqPieV4XrIgHqvB4dlqrFqFhAkPIw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=T1ri6Mw0; 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 DDF41606A31C for ; Mon, 9 Nov 2026 17:07:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=T1ri6Mw0 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E33B1F0089F; Mon, 9 Nov 2026 17:07:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794244020; bh=o0XLFTdWrN2sO/ZXmho8UhMLZmwb5fSxJsxm1JO1NnQ=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=T1ri6Mw0QFyPJcihXpadaZPdI3lB9pEhPM9bSusA/SsCM6ecCGEWRplMOFgN6Kd3o SiRwCKP/Wd26LmEbLIpQxXIWBjo+a5nBsjkyx0luP5lh4hpd9ZYUCMcuupEQrvg+gQ 9Z9BPBUcSuVBCiOQQc8wXtTXLBd5r9HNCHeMYZr5UxSgNnDCiNygvn+sotDYu+HzO/ xN5LXMNJHd31mFrrk7TgLnBUf6PlO6i3oGwnUto0gYzK+wnarskRneeaWTFSwOg9XN cBE5j2TqYWJxd0e4OC7KBJoxphJbQCISwpHRxJIz+WrCHdTWl605bqzc8Nf0z3xurD GiJCX5QMIugdw== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH RFC v3 03/14] ext4: use sb_find_get_block_nonatomic() in ext4_get_inode_loc_noio() Reply-To: sashiko-reviews@lists.linux.dev To: "Christian Brauner" Cc: linux-ext4@vger.kernel.org, tytso@mit.edu In-Reply-To: <20261109-work-inode-metadata_writeback-v3-3-91ac6c024018@kernel.org> References: <20261109-work-inode-metadata_writeback-v3-0-91ac6c024018@kernel.org> <20261109-work-inode-metadata_writeback-v3-3-91ac6c024018@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Mon, 09 Nov 2026 17:06:59 +0000 X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > ext4_get_inode_loc_noio() looks the inode table block up with > sb_find_get_block(). That's the atomic lookup. It serializes against > try_to_free_buffers() with i_private_lock instead of the folio lock and > gives up if the folio is being migrated. So it can report the block as > not cached while it is. >=20 > For ext4_fc_snapshot_inode() that only means falling back to a full > commit. But ext4_sync_inode_metadata() is going to use > ext4_get_inode_loc_noio() to find the inode block that fsync() has to > write out and there a dirty block must not be skipped. >=20 > ext4_fc_snapshot_inode() is the only caller and it can sleep. It runs > under jbd2_journal_lock_updates() and allocates the snapshot with > GFP_NOFS. So use sb_find_get_block_nonatomic() which takes the folio > lock and waits for the migration instead. >=20 > Suggested-by: Jan Kara > Cc: stable@vger.kernel.org # v7.3 > Reviewed-by: Jan Kara > Signed-off-by: Christian Brauner (Amutable) Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261109-work-inode= -metadata_writeback-v3-0-91ac6c024018@kernel.org?part=3D3