| Date | Wed, 21 Nov 2012 17:47:49 -0800 | From | tip-bot for Jacob Shin <> | Subject | [tip:x86/mm2] x86, mm: if kernel .text .data .bss are not marked as E820_RAM, complain and fix |
| |
Commit-ID: 4eea6aa581abfeb2695ebe9f9d4672597e1bdd4b Gitweb: http://git.kernel.org/tip/4eea6aa581abfeb2695ebe9f9d4672597e1bdd4b Author: Jacob Shin <jacob.shin@amd.com> AuthorDate: Fri, 16 Nov 2012 19:38:47 -0800 Committer: H. Peter Anvin <hpa@linux.intel.com> CommitDate: Sat, 17 Nov 2012 11:59:08 -0800
x86, mm: if kernel .text .data .bss are not marked as E820_RAM, complain and fix
There could be cases where user supplied memmap=exactmap memory mappings do not mark the region where the kernel .text .data and .bss reside as E820_RAM, as reported here:
https://lkml.org/lkml/2012/8/14/86
Handle it by complaining, and adding the range back into the e820.
Signed-off-by: Jacob Shin <jacob.shin@amd.com> Link: http://lkml.kernel.org/r/1353123563-3103-11-git-send-email-yinghai@kernel.org Signed-off-by: Yinghai Lu <yinghai@kernel.org> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> --- arch/x86/kernel/setup.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 4bd8921..d85cbd9 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -832,6 +832,20 @@ void __init setup_arch(char **cmdline_p) insert_resource(&iomem_resource, &data_resource); insert_resource(&iomem_resource, &bss_resource); + /* + * Complain if .text .data and .bss are not marked as E820_RAM and + * attempt to fix it by adding the range. We may have a confused BIOS, + * or the user may have incorrectly supplied it via memmap=exactmap. If + * we really are running on top non-RAM, we will crash later anyways. + */ + if (!e820_all_mapped(code_resource.start, __pa(__brk_limit), E820_RAM)) { + pr_warn(".text .data .bss are not marked as E820_RAM!\n"); + + e820_add_region(code_resource.start, + __pa(__brk_limit) - code_resource.start + 1, + E820_RAM); + } + trim_bios_range(); #ifdef CONFIG_X86_32 if (ppro_with_ram_bug()) {
|