Position independent AArch64 code needs to be linked and loaded at the same
relative offset from a 4 KB boundary, or adrp/add and adrp/ldr pairs will
not work correctly. (This is how PC relative symbol references with a 4 GB
reach are emitted)

We need to declare this in the PE/COFF header, otherwise the PE/COFF loader
may load the Image and invoke the stub at an offset which violates this rule.

Signed-off-by: Ard Biesheuvel <[email protected]>
---
 arch/arm64/kernel/head.S | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 0a6e4f924df8..5e83e5b8a9de 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -159,7 +159,7 @@ optional_header:
 
 extra_header_fields:
        .quad   0                               // ImageBase
-       .long   0x20                            // SectionAlignment
+       .long   0x1000                          // SectionAlignment
        .long   0x8                             // FileAlignment
        .short  0                               // MajorOperatingSystemVersion
        .short  0                               // MinorOperatingSystemVersion
@@ -226,7 +226,7 @@ section_table:
        .short  0               // NumberOfRelocations  (0 for executables)
        .short  0               // NumberOfLineNumbers  (0 for executables)
        .long   0xe0500020      // Characteristics (section flags)
-       .align 5
+       .align 12
 #endif
 
 ENTRY(stext)
-- 
1.8.3.2

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