Re: [PATCH] x86/purgatory: Compile purgatory with -D__DISABLE_EXPORTS

[Thomas Huth]

On 25/09/2026 21.16, Eric Biggers wrote:
> On Fri, Sep 25, 2026 at 03:01:49PM +0200, Arnd Bergmann wrote:
> > From: Arnd Bergmann <arnd@xxxxxxxx>
> >
> > A previous patch fixed compile-time issues by setting __NO_FORTIFY
> > for all of the purgatory code, but this is insufficient and still
> > leaves build failures that appeared recently in linux-next:
> >
> > ld.lld: error: undefined symbol: __memset
> > > > > referenced by string.c
> > > > >                arch/x86/purgatory/purgatory.ro:(__UNIQUE_ID_addressable___memset_2)
> >
> > ld.lld: error: undefined symbol: __memmove
> > > > > referenced by string.c
> > > > >                arch/x86/purgatory/purgatory.ro:(__UNIQUE_ID_addressable___memmove_3)
> >
> > Set __DISABLE_EXPORTS as well, to avoid pulling in a reference to the
> > wrong string functions.
> >
> > Fixes: 65cbe410d312 ("x86/purgatory: Compile purgatory with -D__NO_FORTIFY")
> > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> > ---
> >   arch/x86/purgatory/Makefile | 4 +---
> >   1 file changed, 1 insertion(+), 3 deletions(-)
>
> I dropped the patch this fixes already, as I mentioned at
> https://lore.kernel.org/linux-crypto/20260924174911.GA1978@sol/ .  It's
> gone from linux-next now.  I think Thomas Huth is planning to send a
> fixed version, together with the two patches that depend on this.
>
> But compiling all of purgatory (and not just sha256.o as is the status
> quo) with -D__NO_FORTIFY -D__DISABLE_EXPORTS sounds good to me.
Yes, I think that's the way to go, and I've now also verified that the 
change is working. I've now send a new version of the patch here:

 https://lore.kernel.org/lkml/20260928083055.104266-2-thuth@xxxxxxxxxx/

 Thomas