From: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> This patch adds the page size to the arm64 kernel image header so that one can infer the PAGESIZE used by the kernel. This will be helpful to diagnose failures to boot the kernel with page size not supported by the CPU. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> --- Documentation/arm64/booting.txt | 7 ++++++- arch/arm64/kernel/image.h | 5 ++++- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/Documentation/arm64/booting.txt b/Documentation/arm64/booting.txt index 7d9d3c2..aaf6d77 100644 --- a/Documentation/arm64/booting.txt +++ b/Documentation/arm64/booting.txt @@ -104,7 +104,12 @@ Header notes: - The flags field (introduced in v3.17) is a little-endian 64-bit field composed as follows: Bit 0: Kernel endianness. 1 if BE, 0 if LE. - Bits 1-63: Reserved. + Bit 1-2: Kernel Page size. + 0 - Unspecified. + 1 - 4K + 2 - 16K + 3 - 64K + Bits 3-63: Reserved. - When image_size is zero, a bootloader should attempt to keep as much memory as possible free for use by the kernel immediately after the diff --git a/arch/arm64/kernel/image.h b/arch/arm64/kernel/image.h index 8fae075..73b736c 100644 --- a/arch/arm64/kernel/image.h +++ b/arch/arm64/kernel/image.h @@ -47,7 +47,10 @@ #define __HEAD_FLAG_BE 0 #endif -#define __HEAD_FLAGS (__HEAD_FLAG_BE << 0) +#define __HEAD_FLAG_PAGE_SIZE ((PAGE_SHIFT - 10) / 2) + +#define __HEAD_FLAGS (__HEAD_FLAG_BE << 0) | \ + (__HEAD_FLAG_PAGE_SIZE << 1) /* * These will output as part of the Image header, which should be little-endian -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
