Re: [PATCH] x86/apic: Remove dead disable_esr machinery

[Steve Wahl]

On Thu, Sep 03, 2026 at 01:01:23AM +0300, Daniil Tatianin wrote:
> From: Daniil Tatianin <99danilt@xxxxxxxxx>
> 
> apic::disable_esr was a quirk for the 32-bit NUMA-Q, Summit, ES7000 and
> bigsmp platforms, which left the local APIC error status register alone
> because "something untraceable" produced bad interrupts on those
> machines. NUMA-Q, Summit and ES7000 went away in 2014 with commit
> b5660ba76b41 ("x86, platforms: Remove NUMAQ"), commit 7cf6c94591bb
> ("x86, apic: Remove support for IBM Summit/EXA chipset") and commit
> 58f5d2d44883 ("x86, apic: Remove support for ia32-based Unisys ES7000"),
> and the last setter went with commit 0abf508675c0 ("x86/smp: Drop
> 32-bit "bigsmp" machine support"). Every remaining APIC driver
> initializes the flag to zero.
> 
> Remove the flag, the ESR setup bypass keyed on it and the 32-bit only
> ESR clearing hammer in setup_local_APIC(), which was gated on the same
> flag and therefore equally dead.
> 
> No functional changes.
> 
> Signed-off-by: Daniil Tatianin <d-tatianin@xxxxxxxxxxxxxx>

Acked-by: Steve Wahl <steve.wahl@xxxxxxx>


-- 
Steve Wahl, Hewlett Packard Enterprise