Date: Tue, 22 Sep 2015 22:58:22 +0200 From: Palle Girgensohn <girgen@FreeBSD.org> To: Julien Charbon <jch@freebsd.org> Cc: Konstantin Belousov <kostikbel@gmail.com>, freebsd-net@freebsd.org, Hans Petter Selasky <hps@selasky.org> Subject: Re: Kernel panics in tcp_twclose Message-ID: <F9D29C16-502B-43A1-BE2C-D2AD30F0B9EF@FreeBSD.org> In-Reply-To: <56019AF8.8000705@freebsd.org> References: <26B0FF93-8AE3-4514-BDA1-B966230AAB65@FreeBSD.org> <55FC1809.3070903@freebsd.org> <20150918160605.GN67105@kib.kiev.ua> <55FFBE01.6060706@freebsd.org> <3721F099-F45D-4DCD-8AB3-84D1ABC44145@FreeBSD.org> <73856F2B-3E70-483C-9988-C84E798CEB44@FreeBSD.org> <44EBAC98-4761-4E47-8E47-5032430A1C8A@FreeBSD.org> <56019AF8.8000705@freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
> 22 sep 2015 kl. 20:16 skrev Julien Charbon <jch@freebsd.org>:
>=20
>=20
> Hi Palle,
>=20
> On 22/09/15 18:49, Palle Girgensohn wrote:
>>> 22 sep 2015 kl. 18:46 skrev Palle Girgensohn
>>> <girgen@FreeBSD.org>:
>>>> 21 sep 2015 kl. 15:53 skrev Palle Girgensohn
>>>> <girgen@FreeBSD.org>:
>>>>> 21 sep 2015 kl. 10:21 skrev Julien Charbon
>>>>> <jch@FreeBSD.org>: On 18/09/15 18:06, Konstantin Belousov
>>>>> wrote:
>>>>>> On Fri, Sep 18, 2015 at 03:56:25PM +0200, Julien Charbon
>>>>>> wrote:
>>>>>>> [...]
>>>>> - Second, if issue is still in stable/10, compile 10.2 kernel
>>>>> with these options:
>>>>>=20
>>>>> options DDB options DEADLKRES options
>>>>> INVARIANTS options INVARIANT_SUPPORT options
>>>>> WITNESS options WITNESS_SKIPSPIN
>>>>>=20
>>>>> To see where the original fault is coming from.
>>>> [...]
>>>>=20
>>>> I'll try stable/10 now. Would you suggest a "clean" stable/10,
>>>> or could 287621 and 287780 help?
>>>>=20
>>>> I'll add the debugging suggested options right away.
>>>>=20
>>>> Palle
>>>=20
>>> I have a new core dump from ^/stable/10 with:
>>>=20
>>> options DDB options DEADLKRES options
>>> INVARIANTS options INVARIANT_SUPPORT options
>>> WITNESS options WITNESS_SKIPSPIN
>>=20
>> # kgdb kernel /var/crash/vmcore.2 GNU gdb 6.1.1 [FreeBSD] Copyright
>> 2004 Free Software Foundation, Inc. GDB is free software, covered
>> by the GNU General Public License, and you are welcome to change it
>> and/or distribute copies of it under certain conditions. Type "show
>> copying" to see the conditions. There is absolutely no warranty for
>> GDB. Type "show warranty" for details. This GDB was configured as
>> "amd64-marcel-freebsd"...
>>=20
>> Unread portion of the kernel message buffer: panic: tcp_detach:
>> INP_TIMEWAIT && INP_DROPPED && tp !=3D NULL cpuid =3D 16 KDB: stack
>> backtrace: db_trace_self_wrapper() at
>> db_trace_self_wrapper+0x2b/frame 0xfffffe183d9e97e0 kdb_backtrace()
>> at kdb_backtrace+0x39/frame 0xfffffe183d9e9890 vpanic() at
>> vpanic+0x126/frame 0xfffffe183d9e98d0 kassert_panic() at
>> kassert_panic+0x139/frame 0xfffffe183d9e9940 tcp_usr_detach() at
>> tcp_usr_detach+0xf9/frame 0xfffffe183d9e9970 sofree() at
>> sofree+0x1f1/frame 0xfffffe183d9e99a0 soclose() at
>> soclose+0x3a0/frame 0xfffffe183d9e99f0 _fdrop() at
>> _fdrop+0x29/frame 0xfffffe183d9e9a10 closef() at closef+0x1e2/frame
>> 0xfffffe183d9e9aa0 closefp() at closefp+0x9d/frame
>> 0xfffffe183d9e9ae0 amd64_syscall() at amd64_syscall+0x25a/frame
>> 0xfffffe183d9e9bf0 Xfast_syscall() at Xfast_syscall+0xfb/frame
>> 0xfffffe183d9e9bf0 --- syscall (6, FreeBSD ELF64, sys_close), rip =3D
>> 0x801c8d94a, rsp =3D 0x7ffff91c8668, rbp =3D 0x7ffff91c8680 --- KDB:
>> enter: panic Uptime: 18h57m59s Dumping 23085 out of 98263
>> MB:..1%..11%..21%..31%..41%..51%..61%..71%..81%..91%
>>=20
>> Reading symbols from /boot/kernel/nullfs.ko.symbols...done. Loaded
>> symbols for /boot/kernel/nullfs.ko.symbols Reading symbols from
>> /boot/kernel/zfs.ko.symbols...done. Loaded symbols for
>> /boot/kernel/zfs.ko.symbols Reading symbols from
>> /boot/kernel/opensolaris.ko.symbols...done. Loaded symbols for
>> /boot/kernel/opensolaris.ko.symbols Reading symbols from
>> /boot/kernel/ng_bridge.ko.symbols...done. Loaded symbols for
>> /boot/kernel/ng_bridge.ko.symbols Reading symbols from
>> /boot/kernel/netgraph.ko.symbols...done. Loaded symbols for
>> /boot/kernel/netgraph.ko.symbols Reading symbols from
>> /boot/kernel/ng_eiface.ko.symbols...done. Loaded symbols for
>> /boot/kernel/ng_eiface.ko.symbols Reading symbols from
>> /boot/kernel/ng_ether.ko.symbols...done. Loaded symbols for
>> /boot/kernel/ng_ether.ko.symbols Reading symbols from
>> /boot/kernel/accf_data.ko.symbols...done. Loaded symbols for
>> /boot/kernel/accf_data.ko.symbols Reading symbols from
>> /boot/kernel/accf_http.ko.symbols...done. Loaded symbols for
>> /boot/kernel/accf_http.ko.symbols Reading symbols from
>> /boot/kernel/ums.ko.symbols...done. Loaded symbols for
>> /boot/kernel/ums.ko.symbols Reading symbols from
>> /boot/kernel/ng_socket.ko.symbols...done. Loaded symbols for
>> /boot/kernel/ng_socket.ko.symbols Reading symbols from
>> /boot/kernel/fdescfs.ko.symbols...done. Loaded symbols for
>> /boot/kernel/fdescfs.ko.symbols #0 doadump (textdump=3D1) at
>> pcpu.h:219 219 __asm("movq %%gs:%1,%0" : "=3Dr" (td) =
(kgdb) bt #0
>> doadump (textdump=3D1) at pcpu.h:219 #1 0xffffffff8094b337 in
>> kern_reboot (howto=3D260) at /usr/src/sys/kern/kern_shutdown.c:451 #2
>> 0xffffffff8094b845 in vpanic (fmt=3D<value optimized out>, ap=3D<value
>> optimized out>) at /usr/src/sys/kern/kern_shutdown.c:758 #3
>> 0xffffffff8094b6d9 in kassert_panic (fmt=3D<value optimized out>) at
>> /usr/src/sys/kern/kern_shutdown.c:646 #4 0xffffffff80b1ee59 in
>> tcp_usr_detach (so=3D<value optimized out>) at
>> /usr/src/sys/netinet/tcp_usrreq.c:202 #5 0xffffffff809cd291 in
>> sofree (so=3D0xfffff801dd302000) at
>> /usr/src/sys/kern/uipc_socket.c:747 #6 0xffffffff809cdb00 in
>> soclose (so=3D<value optimized out>) at
>> /usr/src/sys/kern/uipc_socket.c:849 #7 0xffffffff808fe659 in
>> _fdrop (fp=3D0xfffff802a593db40, td=3D0x0) at file.h:343 #8
>> 0xffffffff80901092 in closef (fp=3D0xfffff802a593db40,
>> td=3D0xfffff80eebc894a0) at /usr/src/sys/kern/kern_descrip.c:2338 #9
>> 0xffffffff808feb5d in closefp (fdp=3D0xfffff80b20cce000, fd=3D<value
>> optimized out>, fp=3D0xfffff802a593db40, td=3D0xfffff80eebc894a0,
>> holdleaders=3D<value optimized out>) at
>> /usr/src/sys/kern/kern_descrip.c:1194 #10 0xffffffff80d7bc3a in
>> amd64_syscall (td=3D0xfffff80eebc894a0, traced=3D0) at
>> subr_syscall.c:134 #11 0xffffffff80d5f1db in Xfast_syscall () at
>> /usr/src/sys/amd64/amd64/exception.S:396 #12 0x0000000801c8d94a in
>> ?? () Previous frame inner to this frame (corrupt stack?) Current
>> language: auto; currently minimal
>=20
> Thanks for the information. As I suspected the initial error was
> elsewhere than tcp_twclose(), never got this assertion before:
>=20
> tcp_detach: INP_TIMEWAIT && INP_DROPPED && tp !=3D NULL
>=20
> from here:
>=20
> static void
> tcp_detach(struct socket *so, struct inpcb *inp)
> {
> struct tcpcb *tp;
>=20
> INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
> INP_WLOCK_ASSERT(inp);
>=20
> KASSERT(so->so_pcb =3D=3D inp, ("tcp_detach: so_pcb !=3D =
inp"));
> KASSERT(inp->inp_socket =3D=3D so, ("tcp_detach: inp_socket !=3D =
so"));
>=20
> tp =3D intotcpcb(inp);
>=20
> if (inp->inp_flags & INP_TIMEWAIT) {
> if (inp->inp_flags & INP_DROPPED) {
> KASSERT(tp =3D=3D NULL, ("tcp_detach: =
INP_TIMEWAIT
> && "
> "INP_DROPPED && tp !=3D NULL"));
>=20
> Let me check if I could find a path that could lead to this
> unexpected case. Unexpected because: INP_DROPPED and inp->inp_ppcb
> is set to NULL are set at same time here:
>=20
> void
> tcp_twclose(struct tcptw *tw, int reuse)
> {
> struct socket *so;
> struct inpcb *inp;
>=20
> inp =3D tw->tw_inpcb;
> KASSERT((inp->inp_flags & INP_TIMEWAIT), ("tcp_twclose:
> !timewait"));
> KASSERT(intotw(inp) =3D=3D tw, ("tcp_twclose: inp_ppcb !=3D =
tw"));
> INP_INFO_WLOCK_ASSERT(&V_tcbinfo); /* in_pcbfree() */
> INP_WLOCK_ASSERT(inp);
>=20
> tcp_tw_2msl_stop(tw, reuse);
> inp->inp_ppcb =3D NULL;
> in_pcbdrop(inp);
> ...
>=20
> Interesting and by the way could you try:
>=20
> # kgdb kernel /var/crash/vmcore.2
> (kgdb) info threads
>=20
> To see if other thread are also in TCP stack at the same time, and if
> one of this thread is referencing the same inp.
>=20
> Thanks.
>=20
> --
> Julien
>=20
BTW, this backtrace looks quite different from the previous ones? Is it =
a different problem, or just a different way to reveal the same problem?
Palle
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?F9D29C16-502B-43A1-BE2C-D2AD30F0B9EF>