From owner-freebsd-current Thu Feb 22 8:48:24 2001 Delivered-To: freebsd-current@freebsd.org Received: from blizzard.sabbo.net (pop3.sabbo.net [193.193.218.18]) by hub.freebsd.org (Postfix) with ESMTP id A338137B67D; Thu, 22 Feb 2001 08:47:40 -0800 (PST) (envelope-from sobomax@FreeBSD.org) Received: from vic.sabbo.net (root@vic.sabbo.net [193.193.218.112]) by blizzard.sabbo.net (8.10.1/8.10.1) with ESMTP id f1MGitf19820; Thu, 22 Feb 2001 18:45:16 +0200 Received: from FreeBSD.org (big_brother.vega.com [192.168.1.1]) by vic.sabbo.net (8.11.2/8.11.2) with ESMTP id f1MGiiS48322; Thu, 22 Feb 2001 18:44:44 +0200 (EET) (envelope-from sobomax@FreeBSD.org) Message-ID: <3A9541F9.68EDF8D5@FreeBSD.org> Date: Thu, 22 Feb 2001 18:44:41 +0200 From: Maxim Sobolev Organization: Vega International Capital X-Mailer: Mozilla 4.76 [en] (WinNT; U) X-Accept-Language: uk,ru,en MIME-Version: 1.0 To: John Baldwin Cc: Dag-Erling Smorgrav , current@FreeBSD.org, "Alexander N. Kabaev" Subject: Re: A possible bug in the interrupt thread preemption code [Was: References: Content-Type: text/plain; charset=koi8-r Content-Transfer-Encoding: 7bit Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG John Baldwin wrote: > On 22-Feb-01 Maxim Sobolev wrote: > > John Baldwin wrote: > > > >> On 22-Feb-01 Maxim Sobolev wrote: > >> > >> >> > Here it is (from DDB): > >> >> > panic(c027de93,c0297409,c027f878,368,80286) > >> >> > _mtx_assert(c02ea000,9,c027f878,368,80286) > >> >> > mi_switch(c32c5da0,3,c02cea44,c357be98) > >> >> > ithread_schedule(c0747c00,1) > >> >> > sched_ithd(e) > >> >> > Xresume14() > >> >> > --- interrupt, eip = 0xc025b60f, esp = 0x80296, ebp = 0xc357bf08 --- > >> >> > trap(18, 10, 10,c01597b6,20) > >> >> > calltrap() > >> >> > --- trap 0x9, eip = 0xc025a5de, esp = 0xc357bf50, ebp = 0xc357bf64 --- > >> >> > sw1b(c0146cbc,c0146cbc,c32c5da0,c357bf94) > >> >> > ithread_loop(c0747c00,c357bfa8) > >> >> > fork_exit(c0146cbc,c0747c00,c357bfa8) > >> >> > fork_trampoline() > >> >> > >> >> *sigh* This is why enabling interrupts in trap() is such a bad idea. If > >> >> we > >> >> get a trap in the scheduler, then lots of bad crap starts to happen > >> >> because > >> >> we > >> >> can get an interrupt while we are in a trap. :( Can you compile your > >> >> kernel > >> >> with > >> >> INVARIANTS on though, as I think the kernel should've panic'd earlier if > >> >> it > >> >> is > >> >> doing what I think it is doing. > >> > > >> > It's already have INVARIANTS, MUTEX_DEBUG, WITNESS and WITNESS_DDB. > >> > >> Hmm, ouch, you do'nt want MUTEX_DEBUG, that'll slow your system to a crawl. > > > > It doesn't really matter, because system can't even boot into single-user due > > to > > panic. > > > >> >> Also, if you are feeling industrious, edit > >> >> sys/i386/i386/trap.c and comment out the enable_intr() call near the > >> >> beginning > >> >> of the trap() function right after the printf for 'kernel trap %d with > >> >> interrupts disabled'. > >> > > >> > Ok, I'll try so. > >> > > >> > -Maxim > >> > >> It will still panic, just hopefully a better panic. > > > > I did understand that, but the panic I see after the change is exactly the > > same as > > before. Any other ideas? > > A recursive sched_lock? Erm, well, stick these options in your kernel config: > > options KTR > options KTR_EXTEND > options KTR_COMPILE=KTR_LOCK > options KTR_MASK=KTR_MASK Bah, it even doesn't compile with these options: cc -c -pipe -O -march=pentium -Wall -Wredundant-decls -Wnested-externs -Wstrict-prototypes -Wmissing-prototypes -Wpointer-arith -Winline -Wcast-qual -fformat-extensions -ansi -nostdinc -I- -I. -I../.. -I../../dev -I../../../include -I../../contrib/dev/acpica/Subsystem/Include -D_KERNEL -include opt_global.h -elf -mpreferred-stack-boundary=2 ../../kern/kern_ktr.c ../../kern/kern_ktr.c: In function `__Tunable_ktr_mask': ../../kern/kern_ktr.c:95: `KTR_MASK' undeclared (first use in this function) ../../kern/kern_ktr.c:95: (Each undeclared identifier is reported only once ../../kern/kern_ktr.c:95: for each function it appears in.) *** Error code 1 1 error -Maxim To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message