Commit dda56e13 authored by Jacob Shin's avatar Jacob Shin Committed by H. Peter Anvin
Browse files

x86, mm: Fixup code testing if a pfn is direct mapped 



Update code that previously assumed pfns [ 0 - max_low_pfn_mapped ) and
[ 4GB - max_pfn_mapped ) were always direct mapped, to now look up
pfn_mapped ranges instead.

-v2: change applying sequence to keep git bisecting working.
     so add dummy pfn_range_is_mapped(). - Yinghai Lu

Signed-off-by: default avatarJacob Shin <jacob.shin@amd.com>
Link: http://lkml.kernel.org/r/1353123563-3103-12-git-send-email-yinghai@kernel.org


Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
parent 4eea6aa5

arch/x86/include/asm/page_types.h

+8 −0
Original line number Diff line number Diff line
@@ -51,6 +51,14 @@ static inline phys_addr_t get_max_mapped(void) 
	return (phys_addr_t)max_pfn_mapped << PAGE_SHIFT;

}



static inline bool pfn_range_is_mapped(unsigned long start_pfn,

					unsigned long end_pfn)

{

	return end_pfn <= max_low_pfn_mapped ||

	       (end_pfn > (1UL << (32 - PAGE_SHIFT)) &&

		end_pfn <= max_pfn_mapped);

}



extern unsigned long init_memory_mapping(unsigned long start,

					 unsigned long end);

arch/x86/kernel/cpu/amd.c

+3 −5
Original line number Diff line number Diff line
@@ -676,12 +676,10 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c) 
		 * benefit in doing so.

		 */

		if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg)) {

			unsigned long pfn = tseg >> PAGE_SHIFT;



			printk(KERN_DEBUG "tseg: %010llx\n", tseg);

			if ((tseg>>PMD_SHIFT) <

				(max_low_pfn_mapped>>(PMD_SHIFT-PAGE_SHIFT)) ||

				((tseg>>PMD_SHIFT) <

				(max_pfn_mapped>>(PMD_SHIFT-PAGE_SHIFT)) &&

				(tseg>>PMD_SHIFT) >= (1ULL<<(32 - PMD_SHIFT))))

			if (pfn_range_is_mapped(pfn, pfn + 1))

				set_memory_4k((unsigned long)__va(tseg), 1);

		}

	}

arch/x86/platform/efi/efi.c

+3 −4
Original line number Diff line number Diff line
@@ -835,7 +835,7 @@ void __init efi_enter_virtual_mode(void) 
	efi_memory_desc_t *md, *prev_md = NULL;

	efi_status_t status;

	unsigned long size;

	u64 end, systab, end_pfn;

	u64 end, systab, start_pfn, end_pfn;

	void *p, *va, *new_memmap = NULL;

	int count = 0;
@@ -888,10 +888,9 @@ void __init efi_enter_virtual_mode(void) 
		size = md->num_pages << EFI_PAGE_SHIFT;

		end = md->phys_addr + size;



		start_pfn = PFN_DOWN(md->phys_addr);

		end_pfn = PFN_UP(end);

		if (end_pfn <= max_low_pfn_mapped

		    || (end_pfn > (1UL << (32 - PAGE_SHIFT))

			&& end_pfn <= max_pfn_mapped)) {

		if (pfn_range_is_mapped(start_pfn, end_pfn)) {

			va = __va(md->phys_addr);



			if (!(md->attribute & EFI_MEMORY_WB))

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