x86, mm: if kernel .text .data .bss are not marked as E820_RAM, complain and fix (4eea6aa5) · Commits · 戴 / test

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 −0

Original line number	Diff line number	Diff line
		@@ -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()) {

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