Jeremy Fitzhardinge wrote: > head.S creates the very initial pagetable for the kernel. This just > maps enough space for the kernel itself, and an allocation bitmap. > The amount of mapped memory is rounded up to 4Mbytes, and so this > typically ends up mapping 8Mbytes of memory. > > When booting, pagetable_init() needs to create mappings for all > lowmem, and the pagetables for these mappings are allocated from the > free pages around the kernel in low memory. If the number of > pagetable pages + kernel size exceeds head.S's initial mapping, it > will end up faulting on an unmapped page. This will only happen with > specific combinations of kernel size and memory size. > > This patch makes sure that head.S also maps enough space to fit the > kernel pagetables as well as the kernel itself. It ends up using an > additional two pages of unreclaimable memory. > > Signed-off-by: Jeremy Fitzhardinge <jeremy@xxxxxxxxxxxxx> > Acked-by: "H. Peter Anvin" <hpa@xxxxxxxxx> > Cc: Andi Kleen <ak@xxxxxxx> > Cc: Zachary Amsden <zach@xxxxxxxxxx> > Cc: Chris Wright <chrisw@xxxxxxxxxxxx> > Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> > Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>, Is some version of this going in for 2.6.21, or is it not a real problem? _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
