Re: 2.0.31 and kmem

Joerg Pommnitz (pommnitz@darmstadt.gmd.de)
Wed, 12 Nov 1997 16:21:08 +0100

As a guess, this machine is a very old installation
and still uses the kmem based ps package. This ps
directly reads data structures in kernel memory, so
if the kernel data structures layout change, this ps has
to be recompiled (or fixed, if its not just an additional
field in a structure).
What probably happens is, that ps tries to follow
pointers in kmem, that are not longer on the offsets,
that ps expects them to be. As a result, random data
is misinterpreted, which results in the errors you see.

Solution: upgrade your ps suite either to a kmem based
version that works with 2.0.31 (is there one) or switch
to a recent proc fs based version.

Regards
Joerg

Joel Matuseski wrote:
>
> We just upgraded one of our servers to 2.0.31, and after a few
> tries, we still get some funny errors.. for instance output of free
>
> size used cache free shared
> lseek kmem: Unknown error 164351000
> memory: 1312272 -111528560 111528560 1312272 0
> total: 1312272 -111528560 111528560 1312272 0
>
> We've used 2.0.31 on other machines, with no apparent issues. Does anyone
> have any ideas?
>
> ps reports some interesting errors, also..
> error reading kmem (offset = 0x5534ec83)
> lseek kmem: Unknown error 1957472681
> lseek kmem: Unknown error 1958206356
> lseek kmem: Unknown error 1240530875
> error reading kmem (offset = 0x44891840)
> error reading kmem (offset = 0x458b2c24)
> error reading kmem (offset = 0x24448910)
> error reading kmem (offset = 0x247c8d28)
> error reading kmem (offset = 0x247c8940)
> error reading kmem (offset = 0x86a5714)
> error reading kmem (offset = 0x2474b60f)
> lseek kmem: Unknown error 1240508880
> error reading kmem (offset = 0x5338245c)
> lseek kmem: Unknown error 163923992
> error reading kmem (offset = 0x24448dff)
> error reading kmem (offset = 0x2444894e)
> error reading kmem (offset = 0x247c8b24)
> error reading kmem (offset = 0x5de85356)
> lseek kmem: Unknown error 2080377286