amd64 head -r329465 (non-debug build, but with symbols): "panic: spin lock held too long" during make check-old, reported during a sys_vfork
Mark Millard
marklmi26-fbsd at yahoo.com
Sun Feb 18 02:10:29 UTC 2018
[Some more information added, from /usr/libexec/kgdb use.]
On 2018-Feb-17, at 5:39 PM, Mark Millard <marklmi26-fbsd at yahoo.com> wrote:
> This is for FreeBSD running under Hyper-V on a Windows 10 Pro machine.
> The FreeBSD "disk" bindings are to SSDs, not the insides of NTFS files.
> 29 logical processors assigned to FreeBSD (on a 32-thread Ryzen
> Threadripper 1950X). No other Hyper-V use.
>
> This happened during:
>
> # ~/sys_build_scripts.amd64-host/make_powerpc64vtsc_nodebug_clang_altbinutils-amd64-host.sh check-old DESTDIR=/usr/obj/DESTDIRs/clang-powerpc64-installworld_altbinutils
> Script started, output file is /root/sys_typescripts/typescript_make_powerpc64vtsc_nodebug_clang_altbinutils-amd64-host-2018-02-17:15:56:20
>>>> Checking for old files
>
>
> (Hand typed from a picture of a window's content
> at slighly different times, expect typos:)
>
> KDB: enter: panic
> [thread pid 42170 tid 100752 ]
> Stopped at kdb_enter+0x3b: movq $0,kdb_why
> db> call doadump
> Dumping 4825 out of 110559 MB: ... (omitted) ...
> Dump complete
> = 0
>
>
> (The "pid 42170" identification as the process reporting the
> issue does not seem to appear in the core.txt.0 file.)
>
>
> # ls -lTdt /var/crash/*
> -rw-r--r-- 1 root wheel 100792 Feb 17 16:09:18 2018 /var/crash/core.txt.0
> lrwxr-xr-x 1 root wheel 8 Feb 17 16:09:08 2018 /var/crash/vmcore.last -> vmcore.0
> lrwxr-xr-x 1 root wheel 6 Feb 17 16:09:08 2018 /var/crash/info.last -> info.0
> -rw------- 1 root wheel 5060296704 Feb 17 16:09:08 2018 /var/crash/vmcore.0
> -rw------- 1 root wheel 392 Feb 17 16:08:59 2018 /var/crash/info.0
> -rw-r--r-- 1 root wheel 2 Feb 17 16:08:59 2018 /var/crash/bounds
> -rw-r--r-- 1 root wheel 5 Nov 22 04:34:36 2017 /var/crash/minfree
>
> From /var/crash/core.txt.0 :
>
> Unread portion of the kernel message buffer:
> spin lock 0xffffffff81b2dcc0 (sched lock 5) held by 0xfffff8011d936560 (tid 100691) too long
> panic: spin lock held too long
> cpuid = 5
> time = 1518911834
> KDB: stack backtrace:
> db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe00f10094d0
> vpanic() at vpanic+0x18d/frame 0xfffffe00f1009530
> panic() at panic+0x43/frame 0xfffffe00f1009590
> _mtx_lock_indefinite_check() at _mtx_lock_indefinite_check+0x71/frame 0xfffffe00f10095a0
> thread_lock_flags_() at thread_lock_flags_+0xdb/frame 0xfffffe00f1009610
> statclock_cnt() at statclock_cnt+0xdc/frame 0xfffffe00f1009650
> handleevents() at handleevents+0x113/frame 0xfffffe00f10096a0
> timercb() at timercb+0xa9/frame 0xfffffe00f10096f0
> lapic_handle_timer() at lapic_handle_timer+0xa7/frame 0xfffffe00f1009730
> timerint_u() at timerint_u+0x96/frame 0xfffffe00f1009810
> thread_lock_flags_() at thread_lock_flags_+0xc1/frame 0xfffffe00f1009880
> fork1() at fork1+0x1b9f/frame 0xfffffe00f1009930
> sys_vfork() at sys_vfork+0x4c/frame 0xfffffe00f1009980
> amd64_syscall() at amd64_syscall+0xa48/frame 0xfffffe00f1009ab0
> fast_syscall_common() at fast_syscall_common+0x101/frame 0x7fffffffcfc0
> KDB: enter: panic
>
> __curthread () at ./machine/pcpu.h:230
> 230 __asm("movq %%gs:%1,%0" : "=r" (td)
> (kgdb) #0 __curthread () at ./machine/pcpu.h:230
> #1 doadump (textdump=-2122191464) at /usr/src/sys/kern/kern_shutdown.c:347
> #2 0xffffffff8040b42c in db_fncall_generic (addr=<optimized out>,
> rv=<optimized out>, nargs=<optimized out>, args=<optimized out>)
> at /usr/src/sys/ddb/db_command.c:609
> #3 db_fncall (dummy1=<optimized out>, dummy2=<optimized out>,
> dummy3=<optimized out>, dummy4=<optimized out>)
> at /usr/src/sys/ddb/db_command.c:657
> #4 0xffffffff8040af79 in db_command (last_cmdp=<optimized out>,
> cmd_table=<optimized out>, dopager=<optimized out>)
> at /usr/src/sys/ddb/db_command.c:481
> #5 0xffffffff8040acf4 in db_command_loop ()
> at /usr/src/sys/ddb/db_command.c:534
> #6 0xffffffff8040df9f in db_trap (type=<optimized out>, code=<optimized out>)
> at /usr/src/sys/ddb/db_main.c:250
> #7 0xffffffff80b370e3 in kdb_trap (type=3, code=-61456, tf=<optimized out>)
> at /usr/src/sys/kern/subr_kdb.c:697
> #8 0xffffffff80fa2c5c in trap (frame=0xfffffe00f1009400)
> at /usr/src/sys/amd64/amd64/trap.c:547
> #9 <signal handler called>
> #10 kdb_enter (why=0xffffffff811f280b "panic", msg=<optimized out>)
> at /usr/src/sys/kern/subr_kdb.c:479
> #11 0xffffffff80aef17a in vpanic (fmt=<optimized out>, ap=0xfffffe00f1009570)
> at /usr/src/sys/kern/kern_shutdown.c:801
> #12 0xffffffff80aeefc3 in panic (fmt=0x0)
> at /usr/src/sys/kern/kern_shutdown.c:739
> #13 0xffffffff80acfa31 in _mtx_lock_indefinite_check (m=<optimized out>,
> ldap=<optimized out>) at /usr/src/sys/kern/kern_mutex.c:1224
> #14 0xffffffff80acfb9b in thread_lock_flags_ (td=0xfffff818719d1000,
> opts=<optimized out>, file=<optimized out>, line=<optimized out>)
> at /usr/src/sys/kern/kern_mutex.c:913
> #15 0xffffffff80a89d6c in statclock_cnt (cnt=1, usermode=<optimized out>)
> at /usr/src/sys/kern/kern_clock.c:768
> #16 0xffffffff810d0003 in handleevents (now=43230207690178, fake=0)
> at /usr/src/sys/kern/kern_clocksource.c:196
> #17 0xffffffff810d0709 in timercb (et=0xffffffff81c528e8 <lapic_et>,
> arg=<optimized out>) at /usr/src/sys/kern/kern_clocksource.c:353
> #18 0xffffffff8110dad7 in lapic_handle_timer (frame=0xfffffe00f1009740)
> at /usr/src/sys/x86/x86/local_apic.c:1305
> #19 0xffffffff80f849d0 in timerint_u ()
> at /usr/src/sys/amd64/amd64/apic_vector.S:132
> #20 0xfffffe00f1009828 in ?? ()
> #21 0x000000000000b6b1 in ?? ()
> #22 0x0000000000002000 in ?? ()
> #23 0x00000000ffffdfff in ?? ()
> #24 0x00c11c08e43e7fd5 in ?? ()
> #25 0x00000000000003e8 in ?? ()
> #26 0x00000000fffff1eb in ?? ()
> #27 0xfffffe00f1009828 in ?? ()
> #28 0xfffffe00f1009810 in ?? ()
> #29 0x00000000800e6d01 in ?? ()
> #30 0x0000000000000064 in ?? ()
> #31 0xfffff8011d936560 in ?? ()
> #32 0xfffffe00f1009828 in ?? ()
> #33 0xffffffff81771014 in mtx_delay ()
> #34 0x0000000000000000 in ?? ()
> (kgdb)
>
> . . .
> UID PID PPID CPU PRI NI VSZ RSS MWCHAN STAT TT TIME COMMAND
> . . .
> 0 1110 1102 0 33 0 12024 3076 ttyin D+ - 0:00.00 [sh]
> 0 1120 1044 0 20 0 18572 7936 select Ds - 0:00.00 [sshd]
> 1001 1123 1120 0 20 0 18936 8044 select D - 0:00.00 [sshd]
> 1001 1124 1123 0 34 0 12120 3196 wait Ds - 0:00.00 [sh]
> 0 1134 1124 0 22 0 12060 3148 wait D - 0:00.00 [su]
> 0 1135 1134 0 20 0 12312 3244 wait D - 0:00.00 [sh]
> 0 42072 1135 0 25 0 11464 3060 wait D+ - 0:00.00 [sh]
> 0 42072 1135 0 25 0 11464 3060 wait D+ - 0:00.00 [sh]
> 0 42075 42072 0 20 0 10928 2480 select D+ - 0:00.00 [script]
> 0 42076 42075 0 52 0 10160 1396 wait Ds+ - 0:00.00 [make]
> 0 42108 42076 0 52 0 12236 3224 wait D+ - 0:00.00 [make]
> 0 42168 42108 0 52 0 11496 3068 wait D+ - 0:00.00 [sh]
> 0 42169 42168 0 52 0 12608 3568 pipewr D+ - 0:00.00 [make]
> 0 42170 42168 0 72 0 10956 2284 - R+ - 0:00.00 [xargs]
> 0 42171 42168 0 35 0 11500 3064 piperd D+ - 0:00.00 [sh]
> 0 46769 42170 0 72 0 10956 2284 - ?VL+ - 0:00.00 [xargs]
> . . .
>
>
>
>
> Context details:
>
> # uname -apKU
> FreeBSD FBSDFSSD 12.0-CURRENT FreeBSD 12.0-CURRENT r329465M amd64 amd64 1200058 1200058
>
> # svnlite status /usr/src | sort
> ? /usr/src/sys/amd64/conf/GENERIC-DBG
> ? /usr/src/sys/amd64/conf/GENERIC-NODBG
> ? /usr/src/sys/arm/conf/GENERIC-DBG
> ? /usr/src/sys/arm/conf/GENERIC-NODBG
> ? /usr/src/sys/arm64/conf/GENERIC-DBG
> ? /usr/src/sys/arm64/conf/GENERIC-NODBG
> ? /usr/src/sys/powerpc/conf/GENERIC64vtsc-DBG
> ? /usr/src/sys/powerpc/conf/GENERIC64vtsc-NODBG
> ? /usr/src/sys/powerpc/conf/GENERICvtsc-DBG
> ? /usr/src/sys/powerpc/conf/GENERICvtsc-NODBG
> M /usr/src/contrib/llvm/lib/Target/PowerPC/PPCFrameLowering.cpp
> M /usr/src/contrib/llvm/tools/lld/ELF/Arch/PPC64.cpp
> M /usr/src/crypto/openssl/crypto/armcap.c
> M /usr/src/lib/libkvm/kvm_powerpc.c
> M /usr/src/lib/libkvm/kvm_private.c
> M /usr/src/stand/defs.mk
> M /usr/src/stand/powerpc/boot1.chrp/Makefile
> M /usr/src/stand/powerpc/kboot/Makefile
> M /usr/src/sys/arm64/arm64/identcpu.c
> M /usr/src/sys/conf/kmod.mk
> M /usr/src/sys/conf/ldscript.powerpc
> M /usr/src/sys/kern/subr_pcpu.c
> M /usr/src/sys/powerpc/aim/mmu_oea64.c
> M /usr/src/sys/powerpc/ofw/ofw_machdep.c
> M /usr/src/sys/powerpc/powerpc/interrupt.c
> M /usr/src/sys/powerpc/powerpc/mp_machdep.c
> M /usr/src/sys/powerpc/powerpc/trap.c
> M /usr/src/sys/vm/uma_core.c
> M /usr/src/usr.bin/top/machine.c
>
> The GENERIC* files include GENERIC and then set explicit
> debug status choices of mine. Most of the rest is tied to
> historical powerpc and powerpc64 investigations. I also
> have top report the maximum swap-in-use figure that it
> sees during its run.
>
> # svnlite diff /usr/src/sys/vm/uma_core.c
> Index: /usr/src/sys/vm/uma_core.c
> ===================================================================
> --- /usr/src/sys/vm/uma_core.c (revision 329465)
> +++ /usr/src/sys/vm/uma_core.c (working copy)
> @@ -3428,7 +3428,7 @@
> void
> uma_reclaim_wakeup(void)
> {
> -
> +printf("limit %lX, total %lX, needed %d\n", uma_kmem_limit, uma_kmem_total, uma_reclaim_needed);
> if (atomic_fetchadd_int(&uma_reclaim_needed, 1) == 0)
> wakeup(uma_reclaim);
> }
>
>
>
> Side note: It took the automatic fsck and 2 manual fsck
> runs to get back to a clean status (before I could get to
> multi-user).
/usr/local/bin/kgdb did not seem to work. But
/usr/libexec/kgdb seems to. (This is likely the first time
that I've used a normal vmcore.* file on any architecture.
On powerpc I had to hack things into a non-default way of
working. On powerpc64 dumps used to fail.)
# /usr/libexec/kgdb /usr/lib/debug/boot/kernel/kernel.debug /var/crash/vmcore.0
GNU gdb 6.1.1 [FreeBSD]
. . .
So here is what thread 100691 gets as a report in
"info threads" --100752 shows "doadump", but of course
was doing a fork at the time of the problem:
(kgdb) info threads
558 Thread 100691 (PID=46769: xargs) fork_trampoline () at /usr/src/sys/amd64/amd64/exception.S:840
. . .
* 556 Thread 100752 (PID=42170: xargs) doadump (textdump=0x8181ed98) at pcpu.h:230
. . .
The bt for 558 (a.k.a. 100691) does not seem to have much
information:
(kgdb) thread 558
[Switching to thread 558 (Thread 100691)]#0 fork_trampoline () at /usr/src/sys/amd64/amd64/exception.S:840
840 movq %r12,%rdi /* function */
Current language: auto; currently asm
(kgdb) bt
#0 fork_trampoline () at /usr/src/sys/amd64/amd64/exception.S:840
#1 0xffffffff80f8398d in fast_syscall_common () at /usr/src/sys/amd64/amd64/exception.S:480
#2 0x0000000800c43000 in ?? ()
#3 0x0000000000203353 in ?? ()
#4 0x0000000000000001 in .rodata ()
#5 0x0000000800c43008 in ?? ()
#6 0x00c11c08e43e7fd5 in ?? ()
#7 0x0000000000000000 in ?? ()
(kgdb)
But the kernel message buffer material reported:
(repeated from the earlier Email)
spin lock 0xffffffff81b2dcc0 (sched lock 5) held by 0xfffff8011d936560 (tid 100691) too long
I'll note that I have no known way to cause a repeat. I'd been doing the same sort of
build activity for a time when this happened.
===
Mark Millard
marklmi at yahoo.com
( markmi at dsl-only.net is
going away in 2018-Feb, late)
More information about the freebsd-hackers
mailing list