Subject: Re: linux-next: manual merge of the tip tree with Linus' tree

From: Ingo Molnar <[email-masked]>
Date: Wed, 15 Feb 2023 12:15:14 +0100

* Stephen Rothwell <[email-masked]> wrote:

> Hi all,
> 
> Today's linux-next merge of the tip tree got a conflict in:
> 
>   arch/x86/kernel/cpu/common.c
> 
> between commit:
> 
>   be8de49bea50 ("x86/speculation: Identify processors vulnerable to SMT RSB predictions")
> 
> from Linus' tree and commit:
> 
>   e7862eda309e ("x86/cpu: Support AMD Automatic IBRS")
> 
> from the tip 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/kernel/cpu/common.c
> index f3cc7699e1e1,38646f1b5f14..000000000000
> --- a/arch/x86/kernel/cpu/common.c
> +++ b/arch/x86/kernel/cpu/common.c
> @@@ -1403,14 -1412,6 +1414,9 @@@ static void __init cpu_set_bug_bits(str
>   			setup_force_cpu_bug(X86_BUG_RETBLEED);
>   	}
>   
> - 	if (cpu_has(c, X86_FEATURE_IBRS_ENHANCED) &&
> - 	    !cpu_matches(cpu_vuln_whitelist, NO_EIBRS_PBRSB) &&
> - 	    !(ia32_cap & ARCH_CAP_PBRSB_NO))
> - 		setup_force_cpu_bug(X86_BUG_EIBRS_PBRSB);
> - 
>  +	if (cpu_matches(cpu_vuln_blacklist, SMT_RSB))
>  +		setup_force_cpu_bug(X86_BUG_SMT_RSB);
>  +
>   	if (cpu_matches(cpu_vuln_whitelist, NO_MELTDOWN))
>   		return;

Looks good, thanks Stephen!

A similar resolution will show up in tomorrow's -next as well, via:

   e067248949e3 Merge branch 'linus' into x86/cpu, to resolve conflict

... so the conflict should go away in the next -next.

Thanks,

	Ingo