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

[Tony Lindgren]

On Tue, Aug 13, 2024 at 05:31:31PM -0700, Isaku Yamahata wrote:
> On Wed, Aug 14, 2024 at 10:34:11AM +1200,
> "Huang, Kai" <kai.huang@xxxxxxxxx> 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().

I'll do a patch for these changes.

Tony