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Date: Fri, 9 Dec 2022 16:02:27 +0100
From: "Gerd Hoffmann" <kraxel@redhat.com>
To: devel@edk2.groups.io, mcb30@ipxe.org
Cc: Laszlo Ersek <lersek@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>,
	Ard Biesheuvel <ardb@kernel.org>
Subject: Re: [edk2-devel] [PATCH 2/3] OvmfPkg: Add library to handle TPL from within nested interrupt handlers
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  Hi,

[ Cc'ing ard ]

> Add the Nested Interrupt TPL Library (NestedInterruptTplLib) to
> provide helper functions that can be used by nested interrupt handlers
> in place of RaiseTPL()/RestoreTPL().

So, in a nutshell this makes inner interrupt handler only run callbacks
with a priority higher than the priority of the outer interrupt handler.
Anything with equal or lower priority is deferred to the outer handler.
That way we never nest at the same priority, which in turn limits
nesting to the number of different priorities in use.

Correct?

The idea looks sane to me and I couldn't spot any logic errors in this.

take care,
  Gerd