Re: ULE nice bugs are fixed.

On Fri, Apr 11, 2003 at 04:40:17PM -0400, Jeff Roberson wrote:
> 
> On Fri, 11 Apr 2003, Steve Kargl wrote:
> 
> >
> > I started to recompile the kernel and while sitting here decided
> > to load linux-mozilla.  The system rebooted before linux-mozilla
> > displayed a window.  I'm not sure this ULE related.
> >
> > Whoops.  The system just panic after coming back up from
> > a linux-mozilla induce reboot.  I've left the machine
> > at the db> prompt.
> >
> > Here's a hand transcribed backtrace.
> >
> > panic: Negative nice count.
> > Stack backtrace
> > bactrace
> > panic
> > kseq_nice_rem
> > kseq_rem
> > sched_switchout
> > mi_switch
> > msleep
> > g_io_schedule_down
> > g_down_procbody
> > fork_exit
> > fork_trampoline
> >
> 
> In ddb please type 'call kseq_print(0)'  This is on UP right?
I'm seeing quite similar panic, when I do renice to lower (negative) value:
("Negative nice count.")

(kgdb) bt  
#0  doadump () at ../../../kern/kern_shutdown.c:240
#1  0xc018b374 in boot (howto=260) at ../../../kern/kern_shutdown.c:372
#2  0xc018b6aa in panic () at ../../../kern/kern_shutdown.c:545
#3  0xc01926a3 in mi_switch () at ../../../kern/kern_synch.c:481
#4  0xc018b022 in boot (howto=256) at ../../../kern/kern_shutdown.c:312
#5  0xc018b6aa in panic () at ../../../kern/kern_shutdown.c:545
#6  0xc019dbe8 in kseq_nice_rem (kseq=0xc0312be0, nice=-10) at ../../../kern/sched_ule.c:324
#7  0xc019e2b5 in sched_nice (kg=0xfffffff6, nice=-20) at ../../../kern/sched_ule.c:809
#8  0xc0188eac in donice (td=0xc25fc850, p=0xc26c0790, n=-20) at ../../../kern/kern_resource.c:296
#9  0xc0188b43 in setpriority (td=0xc25fc850, uap=0xcdd65d14) at ../../../kern/kern_resource.c:205
#10 0xc0298b11 in syscall (frame=
      {tf_fs = 47, tf_es = 47, tf_ds = 47, tf_edi = 87, tf_esi = -10, tf_ebp = -1077937064, tf_isp = -841589388, tf_ebx = -20, tf_edx = 0, tf_ecx = -1077937080, tf_eax = 96, tf_trapno = 12, tf_err = 2, tf_eip = 671874691, tf_cs = 31, tf_eflags = 659, tf_esp = -1077937108, tf_ss = 47}) at ../../../i386/i386/trap.c:1023
#11 0xc0288d9d in Xint0x80_syscall () at {standard input}:138
---Can't read userspace from dump, or kernel process---

The sources are from today. I also noticed, that 5.1-BETA (build around 9th of
May) is working correctly.

Also: I've noticed a strange behaviour - if I do nice -n -15 some_prog, it
will get a nice of -10, and similiar with any other nice values (it +5 from
what it suposed to be).


Cheers,

Wiktor Niesiobedzki