From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752536AbeEGInS (ORCPT ); Mon, 7 May 2018 04:43:18 -0400 Received: from s3.sipsolutions.net ([144.76.63.242]:58908 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752315AbeEGInN (ORCPT ); Mon, 7 May 2018 04:43:13 -0400 Message-ID: <1525682589.6049.4.camel@sipsolutions.net> Subject: Re: WARNING in kernfs_add_one From: Johannes Berg To: Greg KH , linux-wireless@vger.kernel.org, Eric Dumazet Cc: netdev@vger.kernel.org, syzbot , linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, tj@kernel.org Date: Mon, 07 May 2018 10:43:09 +0200 In-Reply-To: <20180505220721.GA10829@kroah.com> (sfid-20180506_000758_042156_C31EA22A) References: <0000000000000390eb056b77596d@google.com> <20180505164041.GD7746@kroah.com> <095bc684-0029-0b2e-5e28-23376174ca02@gmail.com> <20180505220721.GA10829@kroah.com> (sfid-20180506_000758_042156_C31EA22A) Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.6 (3.26.6-1.fc27) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2018-05-05 at 15:07 -0700, Greg KH wrote: > > > > syzbot found the following crash on: Maybe it should learn to differentiate warnings, if it's going to set panic_on_warn :-) I get why, but still, at least differentiating in the emails wouldn't be bad. > > > > kernfs: ns required in 'ieee80211' for 'phy3' Huh. What does that even mean? > > > > RIP: 0010:kernfs_add_one+0x406/0x4d0 fs/kernfs/dir.c:758 > > > > RSP: 0018:ffff8801ca9eece0 EFLAGS: 00010286 > > > > RAX: 000000000000002d RBX: ffffffff87d5cee0 RCX: ffffffff8160ba7d > > > > RDX: 0000000000000000 RSI: ffffffff81610731 RDI: ffff8801ca9ee840 > > > > RBP: ffff8801ca9eed20 R08: ffff8801d9538500 R09: 0000000000000006 > > > > R10: ffff8801d9538500 R11: 0000000000000000 R12: ffff8801ad1cb6c0 > > > > R13: ffffffff885da640 R14: 0000000000000020 R15: 0000000000000000 > > > > kernfs_create_link+0x112/0x180 fs/kernfs/symlink.c:41 > > > > sysfs_do_create_link_sd.isra.2+0x90/0x130 fs/sysfs/symlink.c:43 > > > > sysfs_do_create_link fs/sysfs/symlink.c:79 [inline] > > > > sysfs_create_link+0x65/0xc0 fs/sysfs/symlink.c:91 > > > > device_add_class_symlinks drivers/base/core.c:1612 [inline] > > > > device_add+0x7a0/0x16d0 drivers/base/core.c:1810 > > > > wiphy_register+0x178a/0x2430 net/wireless/core.c:806 > > > > ieee80211_register_hw+0x13cd/0x35d0 net/mac80211/main.c:1047 > > > > mac80211_hwsim_new_radio+0x1d9b/0x3410 > > > > drivers/net/wireless/mac80211_hwsim.c:2772 > > > > hwsim_new_radio_nl+0x7a7/0xa60 drivers/net/wireless/mac80211_hwsim.c:3246 > > > > genl_family_rcv_msg+0x889/0x1120 net/netlink/genetlink.c:599 Basically we're creating a new virtual radio, which in turn creates a new device, which we have to register. Something is going on with the context here that makes sysfs unhappy, but TBH I have no idea what. johannes