Re: Panic at line 602 in file ffs_vnops.c

----- Original Message ----- 
From: "Willem Jan Withagen" <wjw_at_withagen.nl>

> In an attempt to port some compiler tools, I'm testing its memory allocator.
> And that does not really work, it is a shure way to crash my dual opteron.
> 
> panic: ffs_write: uio -> uio_resid < 0
> at line 602 in file /home2/src/sys/ufs/ffs/ffs_vnop.c
> 
> If I then type 'cont' I'd exepct to get coredump.
> But it just gives up on 708 buffers, prints the uptime
> and sits quitely in a corner until I hard-reset it.
> No other keys will get it back....
> 
> Before it crashes I first get the inocent LOR on ....swap...:1313
> The program usually get an invalid pointer allocated with calloc.
> And as far as I can tell, then crashes on free-ing with this pointer.
> 
> Any takers on this?? 
> Looks to me there are 2 problems:
>     I'm able to upset allocator with this program.
>         (If I write the same program, in shorthand, it stays alive)
>     The system does not want to dump/reboot

To follow up on myself:

'where' after the crash gives: (copied via paper)
ffs_write()   at ... +0x64e
vn_rdwr()     at ... +0xf1
vn_rdwr_inchuncks()    at ... +0x77
elf64_coredump()       at ... +0x1222
coredump()    at ... +0x5da
sigexit()     at ... +0x71
postsig()     at ... +0x30e
ast()         at ... +0x297
Xfas_syscall()         at ... +0xdd

------ syscall(0, FreeBSD ELF64, nosys)
    rip = 0x20067b8ec
    rsp = 0x7fffffffe678
    rbp = 0x2006de6c0

So it looks like the systems want to write a dump, but does not really get
to write it....

What more can I do??

--WjW