Re: [PATCH] ArmVirtPkg/ArmVirtPrePiUniCoreRelocatable: deal with relaxed XIP alignment

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

On 2 August 2016 at 13:35, Laszlo Ersek <lersek@redhat.com> wrote:
> On 08/02/16 12:17, Ard Biesheuvel wrote:
>> Commit b89919ee8f8c ("BaseTools AARCH64: override XIP module linker
>> alignment to 32 bytes") updated the various AARCH64 toolchain definitions
>> to allow SEC, PEI_CORE and PEIM modules to be built with minimal alignment
>> requirements even when using the AArch64 small code model which normally
>> requires 4 KB section alignment.
>>
>> This involves conversion of ADRP instructions into ADR instructions, which
>> can only be done reliably if the ELF and the PE/COFF sections appear at
>> the same offset modulo 4 KB.
>>
>> The ArmVirtPrePiUniCoreRelocatable linker script did not yet take this
>> into account, so update it by starting the .text section at the next
>> appropriately aligned offset PECOFF_HEADER_SIZE bytes into the image.
>>
>> Contributed-under: TianoCore Contribution Agreement 1.0
>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>> ---
>>
>> This fixes the ArmVirtQemuKernel and ArmVirtXen platforms, which are currently
>> broken when using DEBUG_GCC49, DEBUG_GCC5 or *_CLANG35 (all of which received
>> the linker alignment treatment mentioned above)
>>
>> Symptoms: many occurrences of
>> ...
>> GenFw: ERROR 3000: Invalid
>>   WriteSections64(): <../ArmVirtPrePiUniCoreRelocatable.dll> AARCH64 small
>>      code model requires identical ELF and PE/COFF section offsets modulo 4 KB.
>> ...
>>
>> and a failed build.
>>
>>  ArmVirtPkg/PrePi/Scripts/PrePi-PIE.lds | 5 +++--
>>  1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/ArmVirtPkg/PrePi/Scripts/PrePi-PIE.lds b/ArmVirtPkg/PrePi/Scripts/PrePi-PIE.lds
>> index 44df7840adfd..492a8fff380f 100644
>> --- a/ArmVirtPkg/PrePi/Scripts/PrePi-PIE.lds
>> +++ b/ArmVirtPkg/PrePi/Scripts/PrePi-PIE.lds
>> @@ -14,9 +14,10 @@
>>
>>  SECTIONS
>>  {
>> -  .text 0x0 : ALIGN(CONSTANT(COMMONPAGESIZE)) {
>> -    PROVIDE(__reloc_base = .);
>> +  PROVIDE(__reloc_base = .);
>>
>> +  . = PECOFF_HEADER_SIZE;
>> +  .text : ALIGN(CONSTANT(COMMONPAGESIZE)) {
>>      *(.text .text*)
>>      *(.got .got*)
>>      *(.rodata .rodata*)
>>
>
> Acked-by: Laszlo Ersek <lersek@redhat.com>

Pushed as d54e2d6c1e68
Thanks