x86/efi: Use all 64 bit of efi_memmap in setup_e820()

commit 7cc03e48965453b5df1cce5062c826189b04b960 upstream.

The efi_info structure stores low 32 bits of memory map
in efi_memmap and high 32 bits in efi_memmap_hi.

While constructing pointer in the setup_e820(), need
to take into account all 64 bit of the pointer.

It is because on 64bit machine the function
efi_get_memory_map() may return full 64bit pointer and before
the patch that pointer was truncated.

The issue is triggered on Parallles virtual machine and
fixed with this patch.

Signed-off-by: Dmitry Skorodumov <sdmitry@parallels.com>
Cc: Denis V. Lunev <den@openvz.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index 78cbb2db5a8507e190980d2820d4dcde8a3a1c84..ec5a3c7fac7a9f60ff78287f69cc8eff40928c55 100644 (file)
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -560,6 +560,10 @@ static efi_status_t setup_e820(struct boot_params *params,
                unsigned int e820_type = 0;
                unsigned long m = efi->efi_memmap;
 
+#ifdef CONFIG_X86_64
+               m |= (u64)efi->efi_memmap_hi << 32;
+#endif
+
                d = (efi_memory_desc_t *)(m + (i * efi->efi_memdesc_size));
                switch (d->type) {
                case EFI_RESERVED_TYPE: