Commit 7d68dc3f authored by Maarten Lankhorst's avatar Maarten Lankhorst Committed by Ingo Molnar
Browse files

x86, efi: Do not reserve boot services regions within reserved areas 



Commit 916f676f started reserving boot service code since some systems
require you to keep that code around until SetVirtualAddressMap is called.

However, in some cases those areas will overlap with reserved regions.
The proper medium-term fix is to fix the bootloader to prevent the
conflicts from occurring by moving the kernel to a better position,
but the kernel should check for this possibility, and only reserve regions
which can be reserved.

Signed-off-by: default avatarMaarten Lankhorst <m.b.lankhorst@gmail.com>
Link: http://lkml.kernel.org/r/4DF7A005.1050407@gmail.com


Acked-by: default avatarMatthew Garrett <mjg@redhat.com>
Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent c11760c6

arch/x86/include/asm/memblock.h

+1 −1
Original line number Diff line number Diff line
@@ -4,7 +4,6 @@ 
#define ARCH_DISCARD_MEMBLOCK



u64 memblock_x86_find_in_range_size(u64 start, u64 *sizep, u64 align);

void memblock_x86_to_bootmem(u64 start, u64 end);



void memblock_x86_reserve_range(u64 start, u64 end, char *name);

void memblock_x86_free_range(u64 start, u64 end);
@@ -19,5 +18,6 @@ u64 memblock_x86_hole_size(u64 start, u64 end); 
u64 memblock_x86_find_in_range_node(int nid, u64 start, u64 end, u64 size, u64 align);

u64 memblock_x86_free_memory_in_range(u64 addr, u64 limit);

u64 memblock_x86_memory_in_range(u64 addr, u64 limit);

bool memblock_x86_check_reserved_size(u64 *addrp, u64 *sizep, u64 align);



#endif

arch/x86/mm/memblock.c

+2 −2
Original line number Diff line number Diff line
@@ -8,7 +8,7 @@ 
#include <linux/range.h>



/* Check for already reserved areas */

static bool __init check_with_memblock_reserved_size(u64 *addrp, u64 *sizep, u64 align)

bool __init memblock_x86_check_reserved_size(u64 *addrp, u64 *sizep, u64 align)

{

	struct memblock_region *r;

	u64 addr = *addrp, last;
@@ -59,7 +59,7 @@ u64 __init memblock_x86_find_in_range_size(u64 start, u64 *sizep, u64 align) 
		if (addr >= ei_last)

			continue;

		*sizep = ei_last - addr;

		while (check_with_memblock_reserved_size(&addr, sizep, align))

		while (memblock_x86_check_reserved_size(&addr, sizep, align))

			;



		if (*sizep)

arch/x86/platform/efi/efi.c

+25 −4
Original line number Diff line number Diff line
@@ -310,14 +310,31 @@ void __init efi_reserve_boot_services(void) 


	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {

		efi_memory_desc_t *md = p;

		unsigned long long start = md->phys_addr;

		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;

		u64 start = md->phys_addr;

		u64 size = md->num_pages << EFI_PAGE_SHIFT;



		if (md->type != EFI_BOOT_SERVICES_CODE &&

		    md->type != EFI_BOOT_SERVICES_DATA)

			continue;



		memblock_x86_reserve_range(start, start + size, "EFI Boot");

		/* Only reserve where possible:

		 * - Not within any already allocated areas

		 * - Not over any memory area (really needed, if above?)

		 * - Not within any part of the kernel

		 * - Not the bios reserved area

		*/

		if ((start+size >= virt_to_phys(_text)

				&& start <= virt_to_phys(_end)) ||

			!e820_all_mapped(start, start+size, E820_RAM) ||

			memblock_x86_check_reserved_size(&start, &size,

							1<<EFI_PAGE_SHIFT)) {

			/* Could not reserve, skip it */

			md->num_pages = 0;

			memblock_dbg(PFX "Could not reserve boot range "

					"[0x%010llx-0x%010llx]\n",

						start, start+size-1);

		} else

			memblock_x86_reserve_range(start, start+size,

							"EFI Boot");

	}

}
@@ -334,6 +351,10 @@ static void __init efi_free_boot_services(void) 
		    md->type != EFI_BOOT_SERVICES_DATA)

			continue;



		/* Could not reserve boot area */

		if (!size)

			continue;



		free_bootmem_late(start, size);

	}

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE