Commit c16173fa authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Will Deacon
Browse files

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: default avatarMark Salter <msalter@redhat.com>
Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
Acked-by: default avatarLeif Lindholm <leif.lindholm@linaro.org>
Tested-by: default avatarLeif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
parent 113954c6
......@@ -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
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment