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 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 EFI 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 EFI loader.

Signed-off-by: Ard Biesheuvel <ard.biesheu...@linaro.org>
---
 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 5cd1f3491df5..c63f44f20ae3 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -150,7 +150,7 @@ 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
@@ -168,7 +168,7 @@ 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_offset                    // SizeOfHeaders
@@ -215,7 +215,7 @@ 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_offset            // VirtualAddress
        .long   _edata - stext          // SizeOfRawData
        .long   stext_offset            // PointerToRawData
-- 
1.8.3.2

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