Commit 0e691cf8 authored by Yinghai Lu's avatar Yinghai Lu Committed by H. Peter Anvin
Browse files

x86, kexec, 64bit: Only set ident mapping for ram. 



We should set mappings only for usable memory ranges under max_pfn
Otherwise causes same problem that is fixed by

	x86, mm: Only direct map addresses that are marked as E820_RAM

This patch exposes pfn_mapped array, and only sets ident mapping for ranges
in that array.

This patch relies on new kernel_ident_mapping_init that could handle existing
pgd/pud between different calls.

Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1359058816-7615-25-git-send-email-yinghai@kernel.org


Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
parent 9ebdc79f

arch/x86/include/asm/page.h

+4 −0
Original line number Diff line number Diff line
@@ -17,6 +17,10 @@ 


struct page;



#include <linux/range.h>

extern struct range pfn_mapped[];

extern int nr_pfn_mapped;



static inline void clear_user_page(void *page, unsigned long vaddr,

				   struct page *pg)

{

arch/x86/kernel/machine_kexec_64.c

+9 −4
Original line number Diff line number Diff line
@@ -100,10 +100,15 @@ static int init_pgtable(struct kimage *image, unsigned long start_pgtable) 


	level4p = (pgd_t *)__va(start_pgtable);

	clear_page(level4p);

	result = kernel_ident_mapping_init(&info, level4p,

						0, max_pfn << PAGE_SHIFT);

	for (i = 0; i < nr_pfn_mapped; i++) {

		mstart = pfn_mapped[i].start << PAGE_SHIFT;

		mend   = pfn_mapped[i].end << PAGE_SHIFT;



		result = kernel_ident_mapping_init(&info,

						 level4p, mstart, mend);

		if (result)

			return result;

	}



	/*

	 * segments's mem ranges could be outside 0 ~ max_pfn,

arch/x86/mm/init.c

+2 −2
Original line number Diff line number Diff line
@@ -302,8 +302,8 @@ static int __meminit split_mem_range(struct map_range *mr, int nr_range, 
	return nr_range;

}



static struct range pfn_mapped[E820_X_MAX];

static int nr_pfn_mapped;

struct range pfn_mapped[E820_X_MAX];

int nr_pfn_mapped;



static void add_pfn_range_mapped(unsigned long start_pfn, unsigned long end_pfn)

{

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