On 01/28/2013 05:05 PM, Thomas Renninger wrote: > > But this (converting usable memory to reserved one before usable kdump memory > is added) will let machines run into problems again for which the check: > "mmconf area must be in reserved memory" got added? > > If, then memory which was usable before has to be converted to a special > E820_KUMP (or whatever type) to make sure existing checks which look for > "is reserved memory" still work the same way as in a productive kernel. > > Advantage of this would be that the info what originally was usable > memory is preserved and can be used in future kdump related patches. > > So I guess the final patch should be: > - Add a new e820 type: > E820_KDUMP_RESERVED /* Originally usable memory where the crashed > kernel kernel resided in */ > - Use Yinghai's last posted patch, but instead of: > + e820_update_range(0, ULLONG_MAX, E820_RAM, > + E820_RESERVED); > ... > + e820_remove_range(start_at, mem_size, E820_RESERVED, 0); > do: > + e820_update_range(0, ULLONG_MAX, E820_RAM, > + E820_KDUMP_RESERVED); > ... > + e820_remove_range(start_at, mem_size, E820_KDUMP_RESERVED, 0); > > - Come up with another memmap=kdump_reserve_ram memmap option name > or however it should get named... > > If this proposal gets accepted, I can send a tested patch... > Yes, this is much saner. There really shouldn't need to be an option, even; since the tools need to be modified anyway, just modify the actual memory map data structure itself. -hpa
