From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail78-36.sinamail.sina.com.cn (mail78-36.sinamail.sina.com.cn [219.142.78.36]) (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 CC22A101C4 for ; Sat, 13 Jul 2024 01:51:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=219.142.78.36 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720835500; cv=none; b=VO56piTRGfObf7B+Jkhb7i8MlvBaz2VFMorEuY+csDmPOqmlkXXe4Sr5jFR55zg7Amuy4WWjDsP02O4q8utGzjI21SqxAourvRBnEDtfoFKqlTJ7ROsW9QaHfV/Vpr9gb6AwI5DmsewIQ+VznirV+yzxwwLwOxfnhmxaWx2C95U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720835500; c=relaxed/simple; bh=adCyKKkMwjJZDcM9U8gURfC4VUQHEm1LBHVXeI7ccgM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=eiyiXchTB4MTxUv9gzmPAVGpuluhhYF3UUZyGYVxKKh+0+0u8Wn4Ko7PELA47JygEYLVvmHf7yJeKq6U8VKkbcvAA9YLeSQYnvoIrqtmEHzQmArg8fxLV//NtlIzo6WtNzMkwOxmnqsu31/oLf+CTHtBaiQeKHpr/PYHkXVDDHg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sina.com; spf=pass smtp.mailfrom=sina.com; arc=none smtp.client-ip=219.142.78.36 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sina.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sina.com X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([113.118.69.52]) by sina.com (10.185.250.24) with ESMTP id 6691DD0F0000028E; Sat, 13 Jul 2024 09:49:06 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com Authentication-Results: sina.com; spf=none smtp.mailfrom=hdanton@sina.com; dkim=none header.i=none; dmarc=none action=none header.from=hdanton@sina.com X-SMAIL-MID: 13578110748490 X-SMAIL-UIID: B59426E96D894658A91CB898A4239E91-20240713-094906-1 From: Hillf Danton To: syzbot Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [mm?] BUG: unable to handle kernel paging request in list_lru_add Date: Sat, 13 Jul 2024 09:48:58 +0800 Message-Id: <20240713014858.1281-1-hdanton@sina.com> In-Reply-To: <0000000000002d320c061d0ff813@google.com> References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Fri, 12 Jul 2024 10:11:25 -0700 > syzbot has found a reproducer for the following issue on: > > HEAD commit: 43db1e03c086 Merge tag 'for-6.10/dm-fixes-2' of git://git... > git tree: upstream > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12b1da7e980000 #syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 43db1e03c086 --- x/mm/list_lru.c +++ y/mm/list_lru.c @@ -94,6 +94,8 @@ bool list_lru_add(struct list_lru *lru, spin_lock(&nlru->lock); if (list_empty(item)) { l = list_lru_from_memcg_idx(lru, nid, memcg_kmem_id(memcg)); + if (NULL == l) + l = &lru->node[nid].lru; list_add_tail(item, &l->list); /* Set shrinker bit if the first element was added */ if (!l->nr_items++) --