Re: [9front] stats(1) suicide

[arisawa <arisawa@ar.aichi-u.ac.jp>]

Hello cinap,

the experiment below is on my 9front terminal that is executed
from 9front boot loader
	boot from tcp
which means the kernel is not pxe booted from the file server but locally 
loaded from 9fat partition.
the kernel makes cwfs64x cuicide.
on the other hands, the commands are of file servers.

I recompiled cwfs64x
term% ls -l /amd64/bin/cwfs64x
--rwxrwxr-x M 20 arisawa sys 415466 Aug  9 13:27 /amd64/bin/cwfs64x
term% 

term% cwfs64x -f /dev/sdE0/fscache
cwfs64x 730: suicide: invalid address 0x199ab0e40/16384 in sys call pc=0x22ac64
cwfs64x 730: suicide: sys: bad address in syscall pc=0x22ac64
term% 

as you see from the acid output, pread() makes trouble
complaining the read buffer 0x199ab0e40 is invalid.
the value is as much as 6.8G. (I have 16GB ram on the terminal)

Please examine pread() syscall.

Kenji Arisawa

term% broke
echo kill>/proc/730/ctl # cwfs64x
term% acid 730
/proc/730/text:amd64 plan 9 executable
/sys/lib/acid/port
/sys/lib/acid/amd64
acid: lstk()
pread(a0=0x4)+0xe /sys/src/libc/9syscall/pread.s:6
wrenread(b=0x0,d=0xb2b29100,c=0x199ab0e40)+0xaa /sys/src/cmd/cwfs/wren.c:95
	r=0x22261d00000000
	dr=0xb2b29170
devread(c=0x199ab0e40,b=0x0)+0x84 /sys/src/cmd/cwfs/sub.c:989
	e=0x219bbd00000000
getbuf(d=0xb2b29100,addr=0x0,flag=0x5)+0x251 /sys/src/cmd/cwfs/iobuf.c:106
	hp=0x12f4038
	p=0x364e3f0
sysinit()+0x642 /sys/src/cmd/cwfs/config.c:571
	cp=0x1b2b28e40
	d=0xb2b29100
	p=0x21eb5d
	fsp=0x300000000
	ep=0x22ad70
	fs=0x138885477e301960
	error=0x21dd510006bcad
main(argc=0x0,argv=0x7ffffeffef88)+0x247 /sys/src/cmd/cwfs/main.c:342
	nets=0x9c3f00000000
	_args=0x40df7c
	_argc=0x66
	ann=0x0
	i=0x225add00009c3f
_main+0x40 /sys/src/libc/amd64/main9.s:15
acid: 

term% dd -if /dev/sdE0/fscache -count 1 >[2]/dev/null | tr -d '\000'
service cwfs
filsys main c(/dev/sdE0/fscache)(/dev/sdE0/fsworm)
filsys other (/dev/sdE0/other)
filsys dump o
noauth
blocksize 16384
daddrbits 64
indirblks 4
dirblks 6
namelen 144
term% 


maia% 
2014/08/09 7:57、cinap_lenrek@felloff.net のメール：

> kenji,
> 
> the note bug should not apply to release 9front-3730.5d864bfef728.iso.bz2,
> as it was introduced in a later commit. also, cwfs doesnt install any note
> handlers so it cant be affected.
> 
>> cwfs64x 319: suicide: invalid address 0x1056efee8/16384 in syscall pc=0x22ac56
>> cwfs64x 319: suicide: sys: bad address in syscall pc=0x22ac56
> 
> i looked up the pc addresses and it tells me this is the sleep syscall. this
> is very odd. sl and others run cwfs64x just fine on the latest pc64 and i'v
> not seen such an issue yet.
> 
> can you verify by running:
> 
> acid /amd64/bin/cwfs64x
> src(0x22ac56)
> asm(sleep)
> 
> the last line will will disassemble the sleep syscall stub, and should
> result in something like:
> 
> acid: asm(sleep)
> sleep 0x000000000022ac53	MOVQ	BP,a0+0x0(FP)
> sleep+0x5 0x000000000022ac58	MOVQ	$0x11,BP
> sleep+0xc 0x000000000022ac5f	SYSCALL
> sleep+0xe 0x000000000022ac61	RET
> 
> --
> cinap