From nobody Fri Dec 19 13:27:16 2025 Received: from mail-ot1-f69.google.com (mail-ot1-f69.google.com [209.85.210.69]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E5F032D978A for ; Sat, 6 Dec 2025 06:55:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.69 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765004156; cv=none; b=iq7WXujgLpvt28v3ZNsmmCgQsM8hM8ANv/8zVtqzTYAPT97YQOX02NegE04SedhwrHkCe3PFg4C5JjIvQiopizaz0iuRb4FnzJtMhSi2jskjEZ9IxRXU095dAPK7kAFkk+WEt9D49rvQk6SSSDsKJmCxHJlA3ot3mqe5lxNiRsc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765004156; c=relaxed/simple; bh=q5kb2QMUOZQ9RXSgtLJC6gFngrkG0FqfTqYLhROW6o8=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=qByhzg7HpA1p7vRAzvgcmo5z319Ibw0nLmgXVec12LVVpT8jUhwT0iaF9EIL6xfCKuO4HdJ0y6oSj3jM2B1UoUif+8Z3KzZMsebhhvipkQFd5GGNfn87WC3B+jfW8ugiFtbBPOykPxr3tA9BqYD5IY66YlJfxRKRQItJ7UzqLQ4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.210.69 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-ot1-f69.google.com with SMTP id 46e09a7af769-7c76977192eso6248138a34.3 for ; Fri, 05 Dec 2025 22:55:54 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1765004154; x=1765608954; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=afeVOEm+bDmmQfeOPip7AH4c7NgavRosi5dWGCXhU4E=; b=eOUXsmURTOTIu0Al0iChv7V/egxI0Kuum19jTMSyBsTi5sVsD4pgm2pTONDTgXooCJ RVSYp3+pEsC4/ZeeZE821zxgWV2S5unWncSygtTtvFisuJsIvCxLx3RgehGs/asJsz09 umHs0MYtztoWNViWhX9EC7zaosx7uSfvn0fKoN8fznOxYhzR81ftCJsJ3k+K2fTHIRsk wEiSJPyFzb9tVK6ASRejR+Vb0TsGxpR917owmcZ0Of9LhPrvJqvae3OiQl+6W+lw8qmp IuaVBixoKbeBg0B7b4ZAt0BiSU7z0IwELQU9vSqJiULO/+3Je6EE8RTdHps4FkOmCgEL L3IA== X-Gm-Message-State: AOJu0YwqOHOdDtmbT8ffCcP4KFPU/8dDMl7feZNBlrspyVMWVI6smFHF 541M/AGf+Rs/A03Vu2gQ4FgAu7q+cki7xWIb7h7EscsPWJCmzp7/DzZ6PwwwX+A4jcftpo7vMFd CUI9CKRoGWJXjzdWfOcz855TiuU6q8k1ZucqH8/zppS7OxhI5Sa91H0cEZJw= X-Google-Smtp-Source: AGHT+IGf3ovsgYCMT9B62FxeT0tItXJVl3us00ADE3rqXhUCaJdE5lVkJTVSkDQ7CBZMmWNl72qGExIWw5iTpqWYOwo/UosYaxvF Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:220d:b0:659:9a49:8f19 with SMTP id 006d021491bc7-6599a94b99emr698170eaf.42.1765004154151; Fri, 05 Dec 2025 22:55:54 -0800 (PST) Date: Fri, 05 Dec 2025 22:55:54 -0800 In-Reply-To: <69332cf9.a70a0220.243dc6.0011.GAE@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6933d37a.a70a0220.38f243.0017.GAE@google.com> Subject: Forwarded: [PATCH] f2fs: fix hung task in block_operations during checkpoint From: syzbot To: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" For archival purposes, forwarding an incoming command email to linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com. *** Subject: [PATCH] f2fs: fix hung task in block_operations during checkpoint Author: kartikey406@gmail.com #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git= master f2fs_sync_inode_meta() can return 0 (success) even when f2fs_update_inode_page() fails and triggers f2fs_stop_checkpoint(). This happens because the error flag check only occurs at the start of each loop iteration, not after f2fs_update_inode_page() returns. When I/O errors occur: 1. f2fs_update_inode_page() retries 8 times then calls f2fs_stop_checkpoint(), which sets CP_ERROR_FLAG 2. f2fs_sync_inode_meta() returns 0 without checking the error flag 3. block_operations() sees success and loops back to retry_flush_qu= otas 4. Dirty inodes remain on list (sync failed), loop repeats forever 5. Checkpoint never completes, waiters block indefinitely This causes hung tasks when operations like unlink wait for checkpo= int completion while holding locks that other tasks need. Fix by checking f2fs_cp_error() after processing each inode in f2fs_sync_inode_meta() to detect errors from f2fs_update_inode_page= (). Reported-by: syzbot+4235e4d7b6fd75704528@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=3D4235e4d7b6fd75704= 528 Signed-off-by: Deepanshu Kartikey --- fs/f2fs/inode.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index f1cda1900658..8deeb865dbb1 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -763,6 +763,10 @@ void f2fs_update_inode_page(struct inode *inode) struct folio *node_folio; int count =3D 0; retry: + if (unlikely(f2fs_cp_error(sbi))) { + printk("f2fs: f2fs_update_inode_page bailing out due to cp_error\n"); + goto stop_checkpoint; + } node_folio =3D f2fs_get_inode_folio(sbi, inode->i_ino); if (IS_ERR(node_folio)) { int err =3D PTR_ERR(node_folio); --=20 2.43.0