On Sat, Jun 07, 2008 at 06:59:35PM -0500, Alan Cox wrote: > You can download a patch from > http://www.cs.rice.edu/~alc/amd64_kvm_6GB.patch that increases amd64's > kernel virtual address space to 6GB. This patch also increases the > default for the kmem map to almost 2GB. I believe that kernel loadable > modules still work. However, I suspect that mini-dumps are broken. The amd64 modules text/data/bss virtual addresses are allocated from the kernel_map (link_elf_obj.c, link_elf_load_file). Now, the lower end of the kernel_map is top-6Gb.
Kernel code (both kernel proper and modules) is compiled for "kernel memory model", according to the gcc info: `-mcmodel=kernel' Generate code for the kernel code model. The kernel runs in the negative 2 GB of the address space. This model has to be used for Linux kernel code. I suspect we have a problem there. > > I don't plan on committing this patch in its current form. Some of the > changes are done in a hackish way. I am, however, curious to hear > whether or not it works for you. > > Alan
pgpigo0s4evDL.pgp
Description: PGP signature
