Re: [PATCH] x86/nmi: Use trylock in __register_nmi_handler() when in_nmi()

From: Peter Zijlstra
Date: Thu Nov 28 2024 - 04:29:17 EST

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On Wed, Nov 27, 2024 at 06:34:55PM -0500, Waiman Long wrote:
> The __register_nmi_handler() function can be called in NMI context from
> nmi_shootdown_cpus() leading to a lockdep splat like the following.

This seems fundamentally insane. Why are we okay with this?

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In reply to: Waiman Long: "[PATCH] x86/nmi: Use trylock in __register_nmi_handler() when in_nmi()"
Next in thread: Waiman Long: "Re: [PATCH] x86/nmi: Use trylock in __register_nmi_handler() when in_nmi()"
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