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Re: [PATCH 1/3] x86/ucode: Don't use microcode_update_cpu() in early_microcode_load()


  • To: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
  • From: Jan Beulich <jbeulich@xxxxxxxx>
  • Date: Tue, 12 Nov 2024 11:34:16 +0100
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  • Cc: Roger Pau Monné <roger.pau@xxxxxxxxxx>, Xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxxx>
  • Delivery-date: Tue, 12 Nov 2024 10:34:48 +0000
  • List-id: Xen developer discussion <xen-devel.lists.xenproject.org>

On 07.11.2024 13:21, Andrew Cooper wrote:
> There are two callers of microcode_update_cpu(), and because one passes NULL
> and one doesn't, there are effectively two disjoint pieces of logic wrapped in
> a single function.
> 
> early_microcode_load()'s use skips all the microcode_cache handling, and is
> just a simple patch application.
> 
> This skips a redundant collect_cpu_info() call (performed in
> early_microcode_init(), marginally earlier), and avoids holding
> microcode_mutex when we're not interacting with microcode_cache at all.
> 
> No functional change.
> 
> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>

Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>

Personally I would have deemed it more logical (and Misra-compliant) to
remove the "if ( patch )" case from microcode_update_cpu() right here.
Surely (by its title) the next patch is going to have the same effect.

Jan



 


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