[Fwd: kernel panic when using disable_mtrr_trim [was: Re: memorybeyond4GB invisible to the system even though CONFIG_HIGHMEM64G=y]]

From: Yinghai Lu
Date: Tue Jan 20 2009 - 15:43:01 EST

with the config

current tip said:

RELOCS arch/x86/boot/compressed/vmlinux.relocs
WARNING: Absolute relocations present
Offset Info Type Sym.Value Sym.Name
c14d2186 00920e01 R_386_32 c1514000 __per_cpu_load

--- Begin Message --- Hi Yinghai,

When I boot with "disable_mtrr_trim mem=4g", the system boots fine.
Then I changed that to
"disable_mtrr_trim mem=6g" and a kernel panic occurs:

[...] Freeing unused kernel memory: 296k freed
[...] Write protecting the kernel text: 3040k
[...] Write protecting the kernel read-only data: 1352k
[...] khelper used greatest stack depth: 6724 byytes left
[...] Kernel panic - not syncing: No init found. Try passing init=
option to kernel.

I can always reproduce this: all it takes it to boot from a rescue CD,
switch between "mem=4g" and "mem=6g" in /etc/lilo.conf, run lilo and
reboot. If it is 4g, it boots fine; if it is 6g, a kernel panic
occurs. No other changes at all were made.

Same thing (kernel panic) occurs if mem=5g is used.

I am attaching the kernel config used when this happens.

Please let me know how I can help fix this. Does it somehow depend on
all those MTRR/etc memory-related options in the kernel configuration?

Thank you so much,


Attachment: kernel.config
Description: Binary data

--- End Message ---