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LowMem persits, even after deinstalling BadRam

Hi There!

I installed BadRam recently, to block some badram. No I deinstalled it, cleaned the /boot/grub/menu.lst file, and checked if /etc/badram.conf is present. Seems alright. However I do not get rid of it, here is the dmesg output:

BIOS-provided physical RAM map:
BIOS-e820: 0000000000000000 - 000000000009e800 (usable)
BIOS-e820: 000000000009e800 - 00000000000a0000 (reserved)
BIOS-e820: 00000000000d0000 - 00000000000d8000 (reserved)
BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 000000003def0000 (usable)
BIOS-e820: 000000003def0000 - 000000003deff000 (ACPI data)
BIOS-e820: 000000003deff000 - 000000003df00000 (ACPI NVS)
BIOS-e820: 000000003df00000 - 000000003e000000 (usable)
BIOS-e820: 00000000fff00000 - 0000000100000000 (reserved)
Warning only 896MB will be used.
Use a HIGHMEM enabled kernel.
896MB LOWMEM available.

I also installed a customised kernel, and this one does this too. I guess it is somewhere now incorporated, where I cannot see it. Does anyone have an idea how to solve this?
BTW, during installation of the new kernel (make menuconfig), I cannot see an option for using badram configuration.
Thanks you any hints!

AHAB

Do you have more than 896MB of RAM? If so you should do as the kernel says and enable HIGHMEM support. This has nothing to do with badRam.

Quote:

BTW, during installation of the new kernel (make menuconfig), I cannot see an option for using badram configuration.

Did you apply the BadRam patch correctly?

Yeah, I sorted out, or better I have been let to this link:
http://kerneltrap.org/node/2450/7217
which describes the problem with LowMem and HighMem when having 1024MB of RAM.
I could have sworn that I had the same amount of memory already before BadRam installation. I compiled the kernel with HighMem support, now I have the full amount. However In the article they recommend not to enable HighMem on just 1024MB, because the mapping seems to be too intense. Rather, one should be happy, without the 128MB en plus.
Anyway, thanks for your help.

Ahab

Quote:

It is advised to not enable CONFIG_HIGHMEM in the kernel to utilize the extra 128 MB you get for your 1 GB RAM system. I/O Devices cannot directly address high memory from PCI space, so bounce buffers have to be used. Plus the virtual memory management and paging costs come with extra mappings. For details on bounce buffers, refer to Mel Gorman's documentation (link below).

That is very interesting, and is something I would never have considered. Good thing I have 1.5G ;)