Re: [tip: x86/core] x86/alternative: Patch a single alternative location only once

["Jürgen Groß" <jgross@suse.com>]

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On 14.10.25 16:26, Borislav Petkov wrote:
> On Tue, Oct 14, 2025 at 04:22:09PM +0200, Jürgen Groß wrote:
>> I really ran into issues while writing my paravirt MSR series, as I had
>> an ALTERNATIVE3() invocation modifying the original instruction (the
>> indirect paravirt call) with an WRMSR and then trying to turn the no
>> longer existing indirect call into a direct one.
> 
> So put *that* in the commit message. Along with a detailed example of what
> you were seeing. This is bazillion miles more useful than some hypothetically,
> potentially ... case.

I have this here in the commit message:

   - In case of replacing an indirect with a direct call using the
     ALT_FLAG_DIRECT_CALL flag, there is no longer the need to have that
     instance before any other instances at the same location (the
     original instruction is needed for finding the target of the direct
     call).

which is explaining why the problem is occurring. Isn't that enough?


Juergen

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