Memory modified after free 0xfffff8001b210e00(504) val=deadc0dd @ 0xfffff8001b21

[John Baldwin]

On Tuesday 28 September 2004 03:12 am, Kris Kennaway wrote:
> On Mon, Sep 20, 2004 at 11:44:50PM -0700, Kris Kennaway wrote:
> > I just got this panic on an SMP sparc package machine running 6.0:
> >
> > Memory modified after free 0xfffff8001b210e00(504) val=deadc0dd @
> > 0xfffff8001b210f20 panic: Most recently used by file desc
> > cpuid = 0
> > KDB: enter: panic
> > [thread 100195]
> > Stopped at      kdb_enter+0x38: ta              %xcc, 1
> > db> trace
> > panic() at panic+0x19c
> > mtrash_ctor() at mtrash_ctor+0x7c
> > uma_zalloc_arg() at uma_zalloc_arg+0x3e8
> > malloc() at malloc+0xa8
> > fdinit() at fdinit+0x40
> > fdcopy() at fdcopy+0x28
> > fork1() at fork1+0x770
> > fork() at fork+0x10
> > syscall() at syscall+0x220
> > -- syscall (2, FreeBSD ELF64, fork) %o7=0x10fe00 --
> > userland() at 0x40643008
> > user trace: trap %o7=0x10fe00
> > pc 0x40643008, sp 0x7fdffffc3d1
> > pc 0x106e6c, sp 0x7fdffffc491
> > pc 0x1067d0, sp 0x7fdffffc561
> > pc 0x107110, sp 0x7fdffffc621
> > pc 0x10a3b4, sp 0x7fdffffc711
> > pc 0x109c78, sp 0x7fdffffc8a1
> > Dumping 512 MB (1 chunks)
> >   chunk at 0: 536870912 bytes panic: trap: fast data access mmu miss
> > cpuid = 0
> > KDB: enter: panic
> > [thread 100195]
> > Stopped at      kdb_enter+0x38: ta              %xcc, 1
> > db>
>
> Happened again..

Unfortunately it's hard to track these down as we really need to know where it 
was free'd() from and UMA/malloc do not currently have the ability to tell us 
that.

-- 
John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org