Messages in this thread | | | Date | Fri, 24 Aug 2012 18:23:48 -0700 | Subject | Re: [PATCH 5/5] x86: if kernel .text .data .bss are not marked as E820_RAM, complain and fix | From | Yinghai Lu <> |
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On Fri, Aug 24, 2012 at 4:55 PM, Jacob Shin <jacob.shin@amd.com> wrote: > 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> > --- > arch/x86/kernel/setup.c | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c > index 4217fb4..b84aceb5 100644 > --- a/arch/x86/kernel/setup.c > +++ b/arch/x86/kernel/setup.c > @@ -926,6 +926,21 @@ 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, bss_resource.end, E820_RAM)) { > + pr_warn(".text .data .bss are not marked as E820_RAM!\n"); > + > + e820_add_region(code_resource.start, > + bss_resource.end - code_resource.start + 1, > + E820_RAM); > + sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
this sanitze_e820_map could be spared. trim_bios_range will that always.
> + } > + > trim_bios_range(); > #ifdef CONFIG_X86_32 > if (ppro_with_ram_bug()) {
also should use brk_limit instead of bss_resource.end. aka need to keep the map for brk area.
Thanks
Yinghai
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