From c16173fa568582113145daee70fc317b10bc51e0 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 30 Jul 2014 11:59:03 +0100 Subject: [PATCH] arm64/efi: efistub: cover entire static mem footprint in PE/COFF .text The static memory footprint of a kernel Image at boot is larger than the Image file itself. Things like .bss data and initial page tables are allocated statically but populated dynamically so their content is not contained in the Image file. However, if EFI (or GRUB) has loaded the Image at precisely the desired offset of base of DRAM + TEXT_OFFSET, the Image will be booted in place, and we have to make sure that the allocation done by the PE/COFF loader is large enough. Fix this by growing the PE/COFF .text section to cover the entire static memory footprint. The part of the section that is not covered by the payload will be zero initialised by the PE/COFF loader. Acked-by: Mark Salter Acked-by: Mark Rutland Acked-by: Leif Lindholm Tested-by: Leif Lindholm Signed-off-by: Ard Biesheuvel Signed-off-by: Will Deacon --- arch/arm64/kernel/head.S | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 873069056229..0a6e4f924df8 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -151,7 +151,7 @@ optional_header: .short 0x20b // PE32+ format .byte 0x02 // MajorLinkerVersion .byte 0x14 // MinorLinkerVersion - .long _edata - stext // SizeOfCode + .long _end - stext // SizeOfCode .long 0 // SizeOfInitializedData .long 0 // SizeOfUninitializedData .long efi_stub_entry - efi_head // AddressOfEntryPoint @@ -169,7 +169,7 @@ extra_header_fields: .short 0 // MinorSubsystemVersion .long 0 // Win32VersionValue - .long _edata - efi_head // SizeOfImage + .long _end - efi_head // SizeOfImage // Everything before the kernel image is considered part of the header .long stext - efi_head // SizeOfHeaders @@ -216,7 +216,7 @@ section_table: .byte 0 .byte 0 .byte 0 // end of 0 padding of section name - .long _edata - stext // VirtualSize + .long _end - stext // VirtualSize .long stext - efi_head // VirtualAddress .long _edata - stext // SizeOfRawData .long stext - efi_head // PointerToRawData