Re: [PATCH 05/25] KVM: TDX: Add helper functions to print TDX SEAMCALL error

Huang, Kai
2024-08-13T22:34:26Z

>> +#define pr_tdx_error(__fn, __err) \
>> + pr_err_ratelimited("SEAMCALL %s failed: 0x%llx\n", #__fn, __err)
>> +
>> +#define pr_tdx_error_N(__fn, __err, __fmt, ...) \
>> + pr_err_ratelimited("SEAMCALL %s failed: 0x%llx, " __fmt, #__fn, __err, __VA_ARGS__)
>
> Stringify in the inner macro results in expansion of __fn. It means value
> itself, not symbolic string. Stringify should be in the outer macro.
> "SEAMCALL 7 failed" vs "SEAMCALL TDH_MEM_RANGE_BLOCK failed"
>
> #define __pr_tdx_error_N(__fn_str, __err, __fmt, ...) \
> pr_err_ratelimited("SEAMCALL " __fn_str " failed: 0x%llx, " __fmt, __err, __VA_ARGS__)
>
> #define pr_tdx_error_N(__fn, __err, __fmt, ...) \
> __pr_tdx_error_N(#__fn, __err, __fmt, __VA_ARGS__)
>
> #define pr_tdx_error_1(__fn, __err, __rcx) \
> __pr_tdx_error_N(#__fn, __err, "rcx 0x%llx\n", __rcx)
>
> #define pr_tdx_error_2(__fn, __err, __rcx, __rdx) \
> __pr_tdx_error_N(#__fn, __err, "rcx 0x%llx, rdx 0x%llx\n", __rcx, __rdx)
>
> #define pr_tdx_error_3(__fn, __err, __rcx, __rdx, __r8) \
> __pr_tdx_error_N(#__fn, __err, "rcx 0x%llx, rdx 0x%llx, r8 0x%llx\n", __rcx, __rdx, __r8)
>

You are right. Thanks for catching this!

The above code looks good to me, except we don't need pr_tdx_error_N()
anymore.

I think we can just replace the old pr_tdx_error_N() with your
__pr_tdx_error_N().