Reserving memory and /proc/memzones

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This kernel patch is a modified version of Michel Lespinasse's (walken@via.ecp.fr) /proc/memzones patch. It includes the ability to exclude memory addresses from use by marking the memory as reserved. This is useful if you have a slightly defective SIMM, which I happen to have. Since I had the kernel mark the bad memory as reserved, I have had no sig 11 errors while compiling the kernel or anything else. The new kernel command-line option is:

reservemem=<start addr>,<size>,...

Up to five blocks of memory can be reserved. I changed the end of low memory to 0xa0000 instead of 0x9f000. If this causes a problem, (I believe this was a workaround for IBM's ThinkPad) just add: reservemem=0x9f000,0x1000 I changed the kernel option reserve to reserveio to prevent confusion between the two. Here is what /proc/memzones looks like on my system:

Kernel 2.0.30:
00000000-00000fff : reserved
00001000-0009ffff : free
000c0000-000c7fff : rom
000ed000-000edfff : rom
00100000-00182fff : kernel code
00183000-00248fff : kernel data
00249000-00a6ffff : free
00a70000-00a71fff : reserved    <-- This is the location of my bad ram
00a72000-027fffff : free

Kernel 2.1.38:
00000000-00002fff : reserved
00003000-0009ffff : free
000c0000-000c7fff : rom
000ed000-000edfff : rom
00100000-001a6fff : kernel code
001a7000-001b6fff : kernel data
001b7000-001bcfff : free        <-- This gap is caused by freeing the init code
001bd000-00280fff : kernel data
00281000-00a6ffff : free
00a70000-00a71fff : reserved
00a72000-027fffff : free