[edk2-devel] [PATCH V2] UefiCpuPkg/CpuDxe: Fix boot error
Laszlo Ersek
lersek at redhat.com
Thu Jan 7 11:56:47 UTC 2021
Adding James, Mike, and Tom:
On 01/07/21 04:10, Guo Dong wrote:
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3084
>
> When DXE drivers are dispatched above 4GB memory in 64bit
> mode, the address setCodeSelectorLongJump in stack will
> be override by parameter. Jump to Qword is not supported
> by some processors. So use "o64 retf" instead.
>
> Signed-off-by: Guo Dong <guo.dong at intel.com>
> ---
> UefiCpuPkg/CpuDxe/X64/CpuAsm.nasm | 8 +++-----
> 1 file changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/UefiCpuPkg/CpuDxe/X64/CpuAsm.nasm b/UefiCpuPkg/CpuDxe/X64/CpuAsm.nasm
> index c3489bcc3e..a8216cd56f 100644
> --- a/UefiCpuPkg/CpuDxe/X64/CpuAsm.nasm
> +++ b/UefiCpuPkg/CpuDxe/X64/CpuAsm.nasm
> @@ -20,13 +20,11 @@
> ;------------------------------------------------------------------------------
> global ASM_PFX(SetCodeSelector)
> ASM_PFX(SetCodeSelector):
> - sub rsp, 0x10
> + push rcx,
> lea rax, [setCodeSelectorLongJump]
> - mov [rsp], rax
> - mov [rsp+4], cx
> - jmp dword far [rsp]
> + push rax
> + o64 retf
> setCodeSelectorLongJump:
> - add rsp, 0x10
> ret
>
> ;------------------------------------------------------------------------------
>
I'm asking for:
- a Reviewed-by or Tested-by from James please, and
- an Acked-by or Reviewed-by from Mike please, and
- a Reviewed-by or Tested-by from Tom please.
Personally I'm not going to verify the details of the conversion of the
mode switch, from the far jump to the far ret, but squinting from a
distance, the patch looks plausible.
Acked-by: Laszlo Ersek <lersek at redhat.com>
Thanks!
Laszlo
-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#69916): https://edk2.groups.io/g/devel/message/69916
Mute This Topic: https://groups.io/mt/79491640/1813853
Group Owner: devel+owner at edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [edk2-devel-archive at redhat.com]
-=-=-=-=-=-=-=-=-=-=-=-
More information about the edk2-devel-archive
mailing list