Re: page fault in sched_pin()

yeah we know and are just committing the fix..


Don Lewis wrote:
> I just cvsup'ed a few hours ago and I'm getting a page fault in
> sched_pin() early in the boot process.  It looks like a NULL pointer
> dereference.  I'm using SCHED_4BSD+PREEMPTION.
> 
> It looks like the problem is that proc0_init() (which calls schedinit())
> needs to be called before kmeminit(), so that the thread0->td_sched is
> initialized before it is dereferenced in sched_pin().
> 
> The SYSINIT for kmeminit() is SI_SUB_KMEM, which is defined as
> 0x1800000, while the SYSINIT for proc0_init() is SI_SUB_INTRINSIC, which
> is defined as 0x2200000.
> 
> An alternative would be to make sched_pin() a no-op this early in the
> boot process.
> 
> 
> Copyright (c) 1992-2004 The FreeBSD Project.
> Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
>         The Regents of the University of California. All rights reserved.
> FreeBSD 6.0-CURRENT #241: Sat Sep 11 02:23:16 PDT 2004
>     dl_at_scratch.catspoiler.org:/usr/obj/usr/src/sys/GENERICSMB
> WARNING: WITNESS option enabled, expect reduced performance.
> kernel trap 12 with interrupts disabled
> 
> 
> Fatal trap 12: page fault while in kernel mode
> cpuid = 0; apic id = 00
> fault virtual address   = 0x30
> fault code              = supervisor write, page not present
> instruction pointer     = 0x8:0xc0620c47
> stack pointer           = 0x10:0xc0c21cc0
> frame pointer           = 0x10:0xc0c21cc0
> code segment            = base 0x0, limit 0xfffff, type 0x1b
>                         = DPL 0, pres 1, def32 1, gran 1
> processor eflags        = resume, IOPL = 0
> current process         = 0 ()
> [thread 0]
> Stopped at      sched_pin+0xf:  incl    0x30(%eax)
> db> tr
> sched_pin(c0c21cdc,c07a0edc,c1047828,bfeff000,c103a000) at sched_pin+0xf
> pmap_zero_page(c1047828,bfeff000,c103a000,c0c21cf4,c075f724) at pmap_zero_page+0x35
> pmap_growkernel(d6247000) at pmap_growkernel+0xf4
> vm_map_findspace(c103a000,bfeff000,14000000,c08d3c3c) at vm_map_findspace+0x118
> vm_map_find(c103a000,0,0,0,c08d3c3c,14000000,1,7,7,0) at vm_map_find+0x41
> kmem_suballoc(c103a000,c08d3c3c,c08d3c40,14000000,14000) at kmem_suballoc+0x36
> kmeminit(0,c1ec00,c1e000,0,c0440b85) at kmeminit+0xe5
> mi_startup() at mi_startup+0x96
> begin() at begin+0x2c
> db> 
> 
> _______________________________________________
> freebsd-current_at_freebsd.org mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-current
> To unsubscribe, send any mail to "freebsd-current-unsubscribe_at_freebsd.org"