Re: FAILED: patch "[PATCH] x86/sev: Unroll string mmio with" failed to apply to 5.16-stable tree

[Greg KH <gregkh@linuxfoundation.org>]

On Tue, Apr 05, 2022 at 07:29:01PM +0200, Borislav Petkov wrote:
> On Mon, Apr 04, 2022 at 09:43:42AM +0200, gregkh@linuxfoundation.org wrote:
> > The patch below does not apply to the 5.16-stable tree.
> 
> Really?
> 
> $ git checkout -b 5.16.y stable/linux-5.16.y
> Updating files: 100% (19623/19623), done.
> branch '5.16.y' set up to track 'stable/linux-5.16.y'.
> $ git cherry-pick 4009a4ac82dd95b8cd2b62bd30019476983f0aff
> [5.16.y 045eac1dbd58] x86/sev: Unroll string mmio with CC_ATTR_GUEST_UNROLL_STRING_IO
>  Author: Joerg Roedel <jroedel@suse.de>
>  Date: Mon Mar 21 10:33:51 2022 +0100
>  1 file changed, 57 insertions(+), 8 deletions(-)
> $ git status
> On branch 5.16.y
> Your branch is ahead of 'stable/linux-5.16.y' by 1 commit.
>   (use "git push" to publish your local commits)
> 
> It works here...

And then when you build the tree:

arch/x86/lib/iomem.c: In function ‘memcpy_fromio’:
arch/x86/lib/iomem.c:90:29: error: ‘CC_ATTR_GUEST_UNROLL_STRING_IO’ undeclared (first use in this function)
   90 |         if (cc_platform_has(CC_ATTR_GUEST_UNROLL_STRING_IO))
      |                             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/lib/iomem.c:90:29: note: each undeclared identifier is reported only once for each function it appears in
arch/x86/lib/iomem.c: In function ‘memcpy_toio’:
arch/x86/lib/iomem.c:99:29: error: ‘CC_ATTR_GUEST_UNROLL_STRING_IO’ undeclared (first use in this function)
   99 |         if (cc_platform_has(CC_ATTR_GUEST_UNROLL_STRING_IO))
      |                             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/lib/iomem.c: In function ‘memset_io’:
arch/x86/lib/iomem.c:108:29: error: ‘CC_ATTR_GUEST_UNROLL_STRING_IO’ undeclared (first use in this function)
  108 |         if (cc_platform_has(CC_ATTR_GUEST_UNROLL_STRING_IO)) {
      |                             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
make[1]: *** [scripts/Makefile.build:287: arch/x86/lib/iomem.o] Error 1

I only have one "FAILED" email template, do I need another one for when
the patch applies yet breaks the build?

thanks,

greg k-h