Re: HEAD/i386 r320212: three reproducible panics

On Friday 23 June 2017 19:42:55 Oleg V. Nauman wrote:
>  a) Panic on shutdown:
> 
> 
> Fatal trap 1: privileged instruction fault while in kernel mode
> cpuid = 1; apic id = 01
> instruction pointer  = 0x20:0xc6be2023
> stack pointer          = 0x28:0xe13c39f4
> frame pointer          = 0x28:0xe13c3a20
> code segment      = base 0x0, limit 0xfffff, type 0x1b
>          = DPL 0, pres 1, def32 1, gran 1
> processor eflags  = interrupt enabled, resume, IOPL = 0
> current process      = 11 (swi1: netisr 0)
> trap number    = 1
> panic: privileged instruction fault
> cpuid = 1
> time = 1498206262
> Uptime: 6m19s
> 
>  The trace is:
> 
> __curthread () at ./machine/pcpu.h:225
> 225      __asm("movl %%fs:%1,%0" : "=r" (td)
> (kgdb) #0  __curthread () at ./machine/pcpu.h:225
> #1  doadump (textdump=-968633472) at ../../../kern/kern_shutdown.c:318
> #2  0xc06e88c4 in kern_reboot (howto=<optimized out>)
>     at ../../../kern/kern_shutdown.c:386
> #3  0xc06e8c5b in vpanic (fmt=<optimized out>,
>     ap=0xe13c3874 "}\334\235\300H\254 \306\001")
>     at ../../../kern/kern_shutdown.c:779
> #4  0xc06e8b1b in panic (fmt=0xc092e18e "%s")
>     at ../../../kern/kern_shutdown.c:710
> #5  0xc08eed21 in trap_fatal (frame=0xe13c39b4, eva=<optimized out>)
>     at ../../../i386/i386/trap.c:978
> #6  0xc08eea38 in trap (frame=<optimized out>)
>     at ../../../i386/i386/trap.c:704
> #7  <signal handler called>
> #8  0xc6be2023 in ?? ()
> #9  0xc082ed53 in tcp_do_segment (m=<optimized out>, th=<optimized out>,
>     so=<optimized out>, tp=<optimized out>, drop_hdrlen=<optimized out>,
>     tlen=<optimized out>, iptos=<optimized out>,
>     ti_locked=<error reading variable: Cannot access memory at address 0x1>)
> at ../../../netinet/tcp_input.c:2444
> #10 0xc082c181 in tcp_input (mp=<optimized out>, offp=<optimized out>,
>     proto=<optimized out>) at ../../../netinet/tcp_input.c:1191
> #11 0xc0820878 in ip_input (m=0x0) at ../../../netinet/ip_input.c:823
> #12 0xc07d5d0f in netisr_process_workstream_proto (nwsp=<optimized out>,
>     proto=<optimized out>) at ../../../net/netisr.c:899
> #13 swi_net (arg=<optimized out>) at ../../../net/netisr.c:946
> #14 0xc06bb3c5 in intr_event_execute_handlers (p=0x109, ie=<optimized out>)
>     at ../../../kern/kern_intr.c:1336
> #15 0xc06bb5f0 in ithread_execute_handlers (ie=<optimized out>,
>     p=<optimized out>) at ../../../kern/kern_intr.c:1349
> #16 ithread_loop (arg=0xc60e6d00) at ../../../kern/kern_intr.c:1430
> #17 0xc06b8a76 in fork_exit (callout=0xc06bb560 <ithread_loop>,
>     arg=<optimized out>, frame=<optimized out>)
>     at ../../../kern/kern_fork.c:1038
> #18 <signal handler called>
> (kgdb)

 Interesting enough that panic triggered by named shutdown ( well, 'rndc 
flush' is triggering this panic too )

 rndc calling isc__app_ctxrun function and finally panics the system:

---- lib/isc/unix/app.c ---
            return (ISC_R_UNEXPECTED);
         }

#ifndef HAVE_UNIXWARE_SIGWAIT
         result = sigwait(&sset, &sig); <--- panic
         if (result == 0) {

----------------------------
variables are set to:
 sset= {__bits = {16387, 0, 0, 0}}
 sig = 134533280