2023-09-12 17:23:52

by Paolo Bonzini

[permalink] [raw]
Subject: Re: [PATCH v4 00/12] Unify TDCALL/SEAMCALL and TDVMCALL assembly

On 9/12/23 02:57, Huang, Kai wrote:
>>> +#include <asm/tdx.h>
>>>
>>> #include <asm-generic/asm-prototypes.h>
>>>
>> Thanks Paolo!
>>
>> I never met this issue, not even from LKP. Do you happen to know
>> which Kconfig option can trigger this? Or would you mind sharing
>> your .config?
> (replying via outlook due to some networking issue of my home
> network)
>
> After digging, this is due to exporting __seamcall*() assembly
> functions while MODVERSIONS is enabled.
>
> This series itself doesn't cause this warning.
>
> I didn't export them in this series because I would like to leave to
> KVM patches when we are sure we need to export them.
>
> E.g., I have seamcall*() wrappers to retry running out of entropy,
> and we may have concern exporting __seamcall*() low level functions
> directly and may wish to export higher level wrappers.
>
> So I think the fix should be with the patch that truly exports those
> __seamcall*(). I'll talk to Isaku on this to get his idea.

Ah indeed it's not caused by your patches, but rather by the Isaku's KVM
TDX support ("KVM: TDX: Add C wrapper functions for SEAMCALLs to the TDX
module"). The fix is just to squash the #include into his patch.

Paolo


2023-09-14 08:40:16

by Isaku Yamahata

[permalink] [raw]
Subject: Re: [PATCH v4 00/12] Unify TDCALL/SEAMCALL and TDVMCALL assembly

On Tue, Sep 12, 2023 at 03:37:49PM +0200,
Paolo Bonzini <[email protected]> wrote:

> On 9/12/23 02:57, Huang, Kai wrote:
> > > > +#include <asm/tdx.h>
> > > >
> > > > #include <asm-generic/asm-prototypes.h>
> > > >
> > > Thanks Paolo!
> > >
> > > I never met this issue, not even from LKP. Do you happen to know
> > > which Kconfig option can trigger this? Or would you mind sharing
> > > your .config?
> > (replying via outlook due to some networking issue of my home
> > network)
> >
> > After digging, this is due to exporting __seamcall*() assembly
> > functions while MODVERSIONS is enabled.
> >
> > This series itself doesn't cause this warning.
> >
> > I didn't export them in this series because I would like to leave to
> > KVM patches when we are sure we need to export them.
> >
> > E.g., I have seamcall*() wrappers to retry running out of entropy,
> > and we may have concern exporting __seamcall*() low level functions
> > directly and may wish to export higher level wrappers.
> >
> > So I think the fix should be with the patch that truly exports those
> > __seamcall*(). I'll talk to Isaku on this to get his idea.
>
> Ah indeed it's not caused by your patches, but rather by the Isaku's KVM TDX
> support ("KVM: TDX: Add C wrapper functions for SEAMCALLs to the TDX
> module"). The fix is just to squash the #include into his patch.

Yes, I'll squash the fix into the patch.
--
Isaku Yamahata <[email protected]>