On 20.06.23 14:20, kirill.shutemov@xxxxxxxxxxxxxxx wrote:
On Tue, Jun 20, 2023 at 10:37:16AM +0000, Huang, Kai wrote:
+ /*
+ * SEAMCALL caused #GP or #UD. By reaching here %eax contains
+ * the trap number. Convert the trap number to the TDX error
+ * code by setting TDX_SW_ERROR to the high 32-bits of %rax.
+ *
+ * Note cannot OR TDX_SW_ERROR directly to %rax as OR instruction
+ * only accepts 32-bit immediate at most.
Not sure if that comment is really helpful here. It's a common pattern
for large immediates, no?
I am not sure. I guess I am not expert of x86 assembly but only casual writer.
Hi Dave, Kirill,
Are you OK to remove it?
I would rather keep it. I wanted to ask why separate MOV is needed here,
before I read the comment. Also size of $TDX_SW_ERROR is not visible here,
so it contributes to possible confusion without the comment.
Fine with me, but I'd assume that the assembler will simply complain in
case we'd try to use a large immediate.
--
Cheers,
David / dhildenb
