Re: [PATCH 0/5] x86/nmi: Watchdog fixes/improvement Part 1

[Jan Beulich <jbeulich@suse.com>]

On 05.08.2026 14:45, Andrew Cooper wrote:
> This is the start of a very long rabbit hole to address the
> mis-classification of some watchdog NMIs as non-watchdog NMIs.  For
> now, just some simple and hopefully non-controvertial changes.
> 
> https://gitlab.com/xen-project/hardware/xen-staging/-/pipelines/2733861049
> 
> Andrew Cooper (5):
>   x86/nmi: Drop {reserve,release}_lapic_nmi()
>   x86/nmi: Drop K7_NMI_EVENT
>   x86/nmi: Misc style fixes
>   x86/nmi: Check MSR_MISC_ENABLE for all Intel platforms
>   x86/nmi: Don't configure EvtSel repeatedly
> 
>  xen/arch/x86/include/asm/apic.h |   2 -
>  xen/arch/x86/nmi.c              | 153 ++++++++++----------------------
>  2 files changed, 47 insertions(+), 108 deletions(-)

This series, once again, is putting me in a difficult position: Should I look
at it, or should I let it sit for two years or more, just like my earlier
fixes in this area [1], [2] are? (Of course, as always so far, I will look at
the patches, and I will likely also accept them going in ahead of mine. But I
cannot exclude that at some point I might actually stop doing so, seeing how
many of my patches are in that state. While at the same time none of yours
are, afaict, i.e. as per the track record that I keep of what still needs
responding to.)

Yes, you did respond to [1], but is not being comfortable with a change really
a reason to block it, when it _is_ an improvement, and when the alternative
hasn't materialized in all the time?

Jan

[1] https://lists.xen.org/archives/html/xen-devel/2024-01/msg01365.html
[2] https://lists.xen.org/archives/html/xen-devel/2024-04/msg00194.html