LKML Archive on lore.kernel.org
 help / color / Atom feed
From: Dmitry Vyukov <dvyukov@google.com>
To: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Petr Mladek <pmladek@suse.com>,
	Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
	syzkaller <syzkaller@googlegroups.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Fengguang Wu <fengguang.wu@intel.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] printk: inject caller information into the body of message
Date: Wed, 20 Jun 2018 07:44:52 +0200
Message-ID: <CACT4Y+ZGSefrYL9xtQs=yPMRNFsOUumuJXsShJPhCOBSLySxuw@mail.gmail.com> (raw)
In-Reply-To: <CACT4Y+brbqfBWntjVaj-Ri2WhBdXpkA_PYs59qgLZ0vtepZEtw@mail.gmail.com>

On Sat, May 26, 2018 at 8:36 AM, Dmitry Vyukov <dvyukov@google.com> wrote:
> On Thu, May 24, 2018 at 4:14 AM, Sergey Senozhatsky
> <sergey.senozhatsky.work@gmail.com> wrote:
>>> First, we should ask what we expect from this feature.
>>
>> Yeah. Can't really comment on this, it's up to Tetsuo and Dmitry to
>> decide. So far I've seen slightly different requirements/expectations.
>
> The root problem is that it's not possible to make sense out of kernel
> output if message takes more than 1 line (or output non-atomically
> with several printk's) because of intermixed output from several
> tasks/interrupts/etc. For example, it's not generally possible to
> recover crash stack trace, because one gets random mix of frames.
> Humans usually, but not always, can restore most of the sense. So the
> goal is to make this ought-to-be-simple task actually simple and not
> requiring human intelligence and time each time.
>
> Prefixing each line with task/cpu/interrupt context should do the
> trick as it will be possible to split kernel output into multiple
> independent streams and analyze them independently.
>
> In our context (syzbot testing) we can enable an additional config,
> and adopt parser to understand additional line prefix. But I don't
> know how prefixing lines fits into a larger picture. Does it make
> sense to thought out a potential extension story for this format? E.g.
> user specifies set of extension records that are dumped before each
> line, and then can unambiguously parse them? I guess some
> consoles/interfaces will never be extended to provide access to the
> extension records, so it can make sense to make them accessible in
> text format too (optionally).


up

We continue to get mess like this, each instance of which needs to be
checked by human.


BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
sysfs: cannot create duplicate filename '/class/ieee80211/!'
PGD 1cae7e067 P4D 1cae7e067 PUD 1b4da6067 PMD 0
Oops: 0010 [#1] SMP KASAN
CPU: 1 PID: 1728 Comm: syz-executor4 Not tainted 4.17.0+ #84
Hardware name: Google Google Compute Engine/Google Compute Engine,
BIOS Google 01/01/2011
CPU: 0 PID: 1738 Comm: syz-executor7 Not tainted 4.17.0+ #84
RIP: 0010:          (null)
Hardware name: Google Google Compute Engine/Google Compute Engine,
BIOS Google 01/01/2011
Code:
Call Trace:
Bad RIP value.
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
RSP: 0018:ffff88018cd3f590 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff880192f05800 RCX: 1ffffffff10eeea9
 sysfs_warn_dup.cold.3+0x1c/0x2b fs/sysfs/dir.c:30
RDX: ffff88018cd3fab0 RSI: ffff8801c927a480 RDI: ffff88018c77c040
 sysfs_do_create_link_sd.isra.2+0x116/0x130 fs/sysfs/symlink.c:50
RBP: ffff88018cd3f700 R08: 0000000000000001 R09: 0000000000000000
 sysfs_do_create_link fs/sysfs/symlink.c:79 [inline]
 sysfs_create_link+0x65/0xc0 fs/sysfs/symlink.c:91
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff100319a7eb7
R13: ffff88018cd3fab0 R14: ffff880192f05812 R15: ffff880192f05c58
 device_add_class_symlinks drivers/base/core.c:1632 [inline]
 device_add+0x5c9/0x16f0 drivers/base/core.c:1834
FS:  00007f4a8e71f700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000191e1b000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 wiphy_register+0x182e/0x24e0 net/wireless/core.c:813
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 ieee80211_register_hw+0x13cd/0x35d0 net/mac80211/main.c:1050
 sock_poll+0x1d1/0x710 net/socket.c:1168
 mac80211_hwsim_new_radio+0x1da2/0x33b0
drivers/net/wireless/mac80211_hwsim.c:2772
 vfs_poll+0x77/0x2a0 fs/select.c:40
 do_pollfd fs/select.c:848 [inline]
 do_poll fs/select.c:896 [inline]
 do_sys_poll+0x6fd/0x1100 fs/select.c:990
 hwsim_new_radio_nl+0x7b8/0xa60 drivers/net/wireless/mac80211_hwsim.c:3247
 genl_family_rcv_msg+0x889/0x1120 net/netlink/genetlink.c:599
 genl_rcv_msg+0xc6/0x170 net/netlink/genetlink.c:624
 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2448
 __do_sys_poll fs/select.c:1048 [inline]
 __se_sys_poll fs/select.c:1036 [inline]
 __x64_sys_poll+0x189/0x510 fs/select.c:1036
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:635
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x58b/0x740 net/netlink/af_netlink.c:1336
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:290
 netlink_sendmsg+0x9f0/0xfa0 net/netlink/af_netlink.c:1901
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455b29
 sock_sendmsg_nosec net/socket.c:645 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:655
Code:
 ___sys_sendmsg+0x805/0x940 net/socket.c:2161
1d
ba
fb
ff
c3
66
2e
0f
1f
 __sys_sendmsg+0x115/0x270 net/socket.c:2199
84
00
00
00
 __do_sys_sendmsg net/socket.c:2208 [inline]
 __se_sys_sendmsg net/socket.c:2206 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2206
00
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:290
00 66
90
48
89
f8 48
89
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
f7
RIP: 0033:0x455b29
48
Code:
89
1d
d6
ba fb
48
ff
89
c3
ca
66
4d
2e
89
0f
c2
1f
4d
84
89
00
c8
00
4c
00
8b
00
4c
00
24 08
66
0f
90
05 <48>
48
3d
89
01
f8
f0
48
ff ff
89
0f 83
f7
eb
48
b9 fb
89
ff
d6
c3
48 89
66
ca 4d
2e
89
0f
c2
1f
4d
84
89
00
c8
00
4c
00
8b
00
4c
RSP: 002b:00007f4a8e71ec68 EFLAGS: 00000246
24
 ORIG_RAX: 0000000000000007
08
RAX: ffffffffffffffda RBX: 00007f4a8e71f6d4 RCX: 0000000000455b29
0f
RDX: 0000000000000004 RSI: 0000000000000005 RDI: 0000000020000000
05
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
<48> 3d
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
01
R13: 00000000004c06c7 R14: 00000000004d0030 R15: 0000000000000000
f0
Modules linked in:
ff
Dumping ftrace buffer:
ff
   (ftrace buffer empty)
0f
CR2: 0000000000000000
83
---[ end trace 69744e61e26ed6a4 ]---
eb b9 fb ff c3 66 2e
RIP: 0010:          (null)
0f 1f 84 00 00 00
Code:
00
RSP: 002b:00007f4e4fdedc68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
Bad RIP value.
RAX: ffffffffffffffda RBX: 00007f4e4fdee6d4 RCX: 0000000000455b29
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000014
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
RSP: 0018:ffff88018cd3f590 EFLAGS: 00010246
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004c0ee7 R14: 00000000004d0d80 R15: 0000000000000000
RAX: 0000000000000000 RBX: ffff880192f05800 RCX: 1ffffffff10eeea9
RDX: ffff88018cd3fab0 RSI: ffff8801c927a480 RDI: ffff88018c77c040
RBP: ffff88018cd3f700 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff100319a7eb7
R13: ffff88018cd3fab0 R14: ffff880192f05812 R15: ffff880192f05c58
FS:  00007f4a8e71f700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
netlink: 8 bytes leftover after parsing attributes in process `syz-executor2'.
CR2: ffffffffffffffd6 CR3: 0000000191e1b000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

  reply index

Thread overview: 94+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <201804232233.CIC65675.OJSOMFQOFFHVtL@I-love.SAKURA.ne.jp>
     [not found] ` <CACT4Y+boyw_Qy=y-iTnsKZrtTgF0Hk3nHN_xtqUdX4etgiYDQw@mail.gmail.com>
2018-04-24  1:33   ` printk feature for syzbot? Sergey Senozhatsky
2018-04-24 14:40     ` Steven Rostedt
2018-04-26 10:06     ` Petr Mladek
2018-05-10  4:22       ` Sergey Senozhatsky
2018-05-10 11:30         ` Petr Mladek
2018-05-10 12:11           ` Sergey Senozhatsky
2018-05-10 14:22             ` Steven Rostedt
2018-05-10 14:50         ` Tetsuo Handa
2018-05-11  1:45           ` Sergey Senozhatsky
     [not found]             ` <201805110238.w4B2cIGH079602@www262.sakura.ne.jp>
2018-05-11  6:21               ` Sergey Senozhatsky
2018-05-11  9:17                 ` Dmitry Vyukov
2018-05-11  9:50                   ` Sergey Senozhatsky
2018-05-11 11:58                     ` [PATCH] printk: inject caller information into the body of message Tetsuo Handa
2018-05-17 11:21                       ` Sergey Senozhatsky
2018-05-17 11:52                         ` Sergey Senozhatsky
2018-05-18 12:15                         ` Petr Mladek
2018-05-18 12:25                           ` Dmitry Vyukov
2018-05-18 12:54                             ` Petr Mladek
2018-05-18 13:08                               ` Dmitry Vyukov
2018-05-24  2:21                                 ` Sergey Senozhatsky
2018-05-23 10:19                           ` Tetsuo Handa
2018-05-24  2:14                           ` Sergey Senozhatsky
2018-05-26  6:36                             ` Dmitry Vyukov
2018-06-20  5:44                               ` Dmitry Vyukov [this message]
2018-06-20  8:31                                 ` Sergey Senozhatsky
2018-06-20  8:45                                   ` Dmitry Vyukov
2018-06-20  9:06                                     ` Sergey Senozhatsky
2018-06-20  9:18                                       ` Sergey Senozhatsky
2018-06-20  9:31                                         ` Dmitry Vyukov
2018-06-20 11:07                                           ` Sergey Senozhatsky
2018-06-20 11:32                                             ` Dmitry Vyukov
2018-06-20 13:06                                               ` Sergey Senozhatsky
2018-06-22 13:06                                                 ` Tetsuo Handa
2018-06-25  1:41                                                   ` Sergey Senozhatsky
2018-06-25  9:36                                                     ` Dmitry Vyukov
2018-06-27 10:29                                                       ` Tetsuo Handa
2018-09-10 11:20                                                 ` Alexander Potapenko
2018-09-12  6:53                                                   ` Sergey Senozhatsky
2018-09-12 16:05                                                     ` Steven Rostedt
2018-09-13  7:12                                                       ` Sergey Senozhatsky
2018-09-13 12:26                                                         ` Petr Mladek
2018-09-13 14:28                                                           ` Sergey Senozhatsky
2018-09-14  1:22                                                             ` Steven Rostedt
2018-09-14  2:15                                                               ` Sergey Senozhatsky
2018-09-14  6:57                                                             ` Sergey Senozhatsky
2018-09-14 10:37                                                               ` Tetsuo Handa
2018-09-14 11:50                                                                 ` Sergey Senozhatsky
2018-09-14 12:03                                                                   ` Tetsuo Handa
2018-09-14 12:22                                                                     ` Sergey Senozhatsky
2018-09-19 11:02                                                                       ` Tetsuo Handa
2018-09-24  8:11                                                                         ` Tetsuo Handa
2018-09-27 16:10                                                                           ` Tetsuo Handa
2018-09-28  9:02                                                                             ` Sergey Senozhatsky
2018-09-28  9:09                                                                           ` Sergey Senozhatsky
2018-09-28 11:01                                                                             ` Tetsuo Handa
2018-09-29 10:51                                                                               ` Sergey Senozhatsky
2018-09-29 11:15                                                                                 ` Tetsuo Handa
2018-10-01  2:37                                                                                   ` Sergey Senozhatsky
2018-10-01  2:58                                                                                     ` Sergey Senozhatsky
2018-10-01 11:21                                                                                     ` Tetsuo Handa
2018-10-02  6:38                                                                                       ` Sergey Senozhatsky
2018-10-08 10:31                                                                                         ` Tetsuo Handa
2018-10-08 16:03                                                                                           ` Petr Mladek
2018-10-08 20:48                                                                                             ` Tetsuo Handa
2018-10-09 14:52                                                                                               ` Petr Mladek
2018-10-09 21:19                                                                                                 ` Tetsuo Handa
2018-10-10 10:14                                                                                                   ` Tetsuo Handa
2018-10-11 10:20                                                                                                     ` Tetsuo Handa
2018-10-11 13:47                                                                                                       ` Steven Rostedt
2018-10-08 15:43                                                                                         ` Petr Mladek
2018-09-28  8:56                                                                         ` Sergey Senozhatsky
2018-09-28 11:21                                                                           ` Tetsuo Handa
2018-09-29 11:13                                                                             ` Sergey Senozhatsky
2018-09-29 11:39                                                                               ` Tetsuo Handa
2018-10-01  5:52                                                                               ` Sergey Senozhatsky
2018-10-01  8:37                                                                                 ` Sergey Senozhatsky
2018-10-01 18:06                                                                               ` Steven Rostedt
2018-09-14  1:12                                                         ` Steven Rostedt
2018-09-14  1:55                                                           ` Sergey Senozhatsky
2018-06-21  8:29                                               ` Sergey Senozhatsky
2018-06-20  9:30                                       ` Dmitry Vyukov
2018-06-20 11:19                                         ` Sergey Senozhatsky
2018-06-20 11:25                                           ` Dmitry Vyukov
2018-06-20 11:37                                         ` Fengguang Wu
2018-06-20 12:31                                           ` Dmitry Vyukov
2018-06-20 12:41                                             ` Fengguang Wu
2018-06-20 12:45                                               ` Dmitry Vyukov
2018-06-20 12:48                                                 ` Fengguang Wu
2018-05-11 13:37                     ` printk feature for syzbot? Steven Rostedt
2018-05-15  5:20                       ` Sergey Senozhatsky
2018-05-15 14:39                         ` Steven Rostedt
2018-05-11 11:02                 ` [PATCH] printk: fix possible reuse of va_list variable Tetsuo Handa
2018-05-11 11:27                   ` Sergey Senozhatsky
2018-05-17 11:57                   ` Petr Mladek

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='CACT4Y+ZGSefrYL9xtQs=yPMRNFsOUumuJXsShJPhCOBSLySxuw@mail.gmail.com' \
    --to=dvyukov@google.com \
    --cc=akpm@linux-foundation.org \
    --cc=fengguang.wu@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=penguin-kernel@i-love.sakura.ne.jp \
    --cc=pmladek@suse.com \
    --cc=rostedt@goodmis.org \
    --cc=sergey.senozhatsky.work@gmail.com \
    --cc=sergey.senozhatsky@gmail.com \
    --cc=syzkaller@googlegroups.com \
    --cc=torvalds@linux-foundation.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

LKML Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/lkml/0 lkml/git/0.git
	git clone --mirror https://lore.kernel.org/lkml/1 lkml/git/1.git
	git clone --mirror https://lore.kernel.org/lkml/2 lkml/git/2.git
	git clone --mirror https://lore.kernel.org/lkml/3 lkml/git/3.git
	git clone --mirror https://lore.kernel.org/lkml/4 lkml/git/4.git
	git clone --mirror https://lore.kernel.org/lkml/5 lkml/git/5.git
	git clone --mirror https://lore.kernel.org/lkml/6 lkml/git/6.git
	git clone --mirror https://lore.kernel.org/lkml/7 lkml/git/7.git
	git clone --mirror https://lore.kernel.org/lkml/8 lkml/git/8.git
	git clone --mirror https://lore.kernel.org/lkml/9 lkml/git/9.git
	git clone --mirror https://lore.kernel.org/lkml/10 lkml/git/10.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 lkml lkml/ https://lore.kernel.org/lkml \
		linux-kernel@vger.kernel.org
	public-inbox-index lkml

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-kernel


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git