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I have a laptop with some corrupted ram addresses, so I'm trying to use memmap to reserve them before linux boots up.

I have been trying to use memmap=10M$1024M as a kernel boot option, but linux crashes (with no errors) and restarts. If I use a different syntax for memmap like memmap=1023M@0M it boots fine.

Do I have to specify a certain size block to reserve or could my kernel version not support reserving memory with memmap?

Maybe I'm better off using memmap=exactmap, and if so, could somebody point me to a good faq on how to use it?

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i stumbled upon this:

This command notifies the memory manager that specified regions of RAM ought to be filtered out (usually, because they're damaged). This remains in effect after a payload kernel has been loaded by GRUB, as long as the loaded kernel obtains its memory map f> rom GRUB. Kernels that support this include Linux, GNU Mach, the kernel of FreeBSD and Multiboot kernels in general.

maybe that helps?

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Im currently in a foreign country where its difficult to get any new parts, so Im looking for a fix for the next two months. – alexl Feb 12 '11 at 16:32
Use memtest86 and set badram parameters.... – ZaB Feb 18 '12 at 23:18

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