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

Isaku Yamahata
2024-08-14T00:31:32Z

On Wed, Aug 14, 2024 at 10:34:11AM +1200,
"Huang, Kai" <kai.huang@intel.com> wrote:

>
> > > +#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().

Agreed, we don't have the direct user of pr_tdx_error_N().
--
Isaku Yamahata <isaku.yamahata@intel.com>