On Mon, Jul 14, 2008 at 2:44 AM, Eric W. Biederman <ebiederm at xmission.com> wrote: > Bernhard Walle <bwalle at suse.de> writes: > >> * Yinghai Lu [2008-07-14 00:11]: >>> >>> should use min_t(u64, 1ULL<<32, max_low_pfn<<PAGE_SHIFT) replace ULONG_MAX >> >> Shouldn't we use min_t(u64, ULLONG_MAX, max_low_pfn<<PAGE_SHIFT), i.e. >> should we really limit the crashkernel to a 32 bit address on a 64 bit >> system? > > We should use the lowest physical address that meets our size and > alignment constraints. However there is no reason to make this be < > 4G or even < 1G. The worst case is that we reserve an area the kdump > kernel can't run out of. However /sbin/kexec should check for that as > the kexec on panic code is not necessarily a linux kernel. for 64bit, kdump can start from address above 4g with bzImage? YH
