Hi all,

Today's linux-next merge of the kvm-x86 tree got a conflict in:

  arch/x86/include/asm/cpufeatures.h

between commits:

  6ffdb49101f0 ("x86/cpufeatures: Add X86_FEATURE_SGX_EUPDATESVN feature flag")
  3767def18f4c ("x86/cpufeatures: Add support for L3 Smart Data Cache Injection Allocation Enforcement")

from the tip tree and commits:

  5d0316e25def ("x86/cpufeatures: Add X86_FEATURE_X2AVIC_EXT")
  f6106d41ec84 ("x86/bugs: Use an x86 feature to track the MMIO Stale Data mitigation")

from the kvm-x86 tree.

I fixed it up (see below) and can carry the fix as necessary. This
is now fixed as far as linux-next is concerned, but any non trivial
conflicts should be mentioned to your upstream maintainer when your tree
is submitted for merging.  You may also want to consider cooperating
with the maintainer of the conflicting tree to minimise any particularly
complex conflicts.

-- 
Cheers,
Stephen Rothwell

diff --cc arch/x86/include/asm/cpufeatures.h
index d90ce601917c,646d2a77a2e2..000000000000
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@@ -503,9 -500,12 +504,15 @@@
  #define X86_FEATURE_IBPB_EXIT_TO_USER	(21*32+14) /* Use IBPB on exit-to-userspace, see VMSCAPE bug */
  #define X86_FEATURE_ABMC		(21*32+15) /* Assignable Bandwidth Monitoring Counters */
  #define X86_FEATURE_MSR_IMM		(21*32+16) /* MSR immediate form instructions */
 -#define X86_FEATURE_X2AVIC_EXT		(21*32+17) /* AMD SVM x2AVIC support for 4k vCPUs */
 -#define X86_FEATURE_CLEAR_CPU_BUF_VM_MMIO (21*32+18) /*
 +#define X86_FEATURE_SGX_EUPDATESVN	(21*32+17) /* Support for ENCLS[EUPDATESVN] instruction */
 +
 +#define X86_FEATURE_SDCIAE		(21*32+18) /* L3 Smart Data Cache Injection Allocation Enforcement */
++#define X86_FEATURE_X2AVIC_EXT		(21*32+19) /* AMD SVM x2AVIC support for 4k vCPUs */
++#define X86_FEATURE_CLEAR_CPU_BUF_VM_MMIO (21*32+20) /*
+ 						      * Clear CPU buffers before VM-Enter if the vCPU
+ 						      * can access host MMIO (ignored for all intents
+ 						      * and purposes if CLEAR_CPU_BUF_VM is set).
+ 						      */
  
  /*
   * BUG word(s)

On Tue, Nov 25, 2025 at 03:59:53PM +1100, Stephen Rothwell wrote:
> diff --cc arch/x86/include/asm/cpufeatures.h
> index d90ce601917c,646d2a77a2e2..000000000000
> --- a/arch/x86/include/asm/cpufeatures.h
> +++ b/arch/x86/include/asm/cpufeatures.h
> @@@ -503,9 -500,12 +504,15 @@@
>   #define X86_FEATURE_IBPB_EXIT_TO_USER	(21*32+14) /* Use IBPB on exit-to-userspace, see VMSCAPE bug */
>   #define X86_FEATURE_ABMC		(21*32+15) /* Assignable Bandwidth Monitoring Counters */
>   #define X86_FEATURE_MSR_IMM		(21*32+16) /* MSR immediate form instructions */
>  -#define X86_FEATURE_X2AVIC_EXT		(21*32+17) /* AMD SVM x2AVIC support for 4k vCPUs */
>  -#define X86_FEATURE_CLEAR_CPU_BUF_VM_MMIO (21*32+18) /*
>  +#define X86_FEATURE_SGX_EUPDATESVN	(21*32+17) /* Support for ENCLS[EUPDATESVN] instruction */
>  +
>  +#define X86_FEATURE_SDCIAE		(21*32+18) /* L3 Smart Data Cache Injection Allocation Enforcement */
> ++#define X86_FEATURE_X2AVIC_EXT		(21*32+19) /* AMD SVM x2AVIC support for 4k vCPUs */
> ++#define X86_FEATURE_CLEAR_CPU_BUF_VM_MMIO (21*32+20) /*
> + 						      * Clear CPU buffers before VM-Enter if the vCPU
> + 						      * can access host MMIO (ignored for all intents
> + 						      * and purposes if CLEAR_CPU_BUF_VM is set).
> + 						      */

Yeah, I caught this already during review, we will make sure to let Linus know
when we send the pull requests.

Thx.

-- 
Regards/Gruss,
    Boris.

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