Date:   Mon, 20 Mar 2023 21:03:21 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Jeremi Piotrowski <jpiotrowski@linux.microsoft.com>
Cc:     linux-kernel@vger.kernel.org,
        Brijesh Singh <brijesh.singh@amd.com>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        "Kalra, Ashish" <ashish.kalra@amd.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org
Subject: Re: [PATCH v3 3/8] x86/psp: Register PSP platform device when ASP
 table is present
Message-ID: <20230320200321.GDZBi8CXCyE6kD7qSN@fat_crate.local>
References: <20230320191956.1354602-1-jpiotrowski@linux.microsoft.com>
 <20230320191956.1354602-4-jpiotrowski@linux.microsoft.com>
 <20230320192504.GCZBizEGDjVtGWpNP3@fat_crate.local>
 <6d3d512b-55e9-8205-461c-02f1e71f2b63@linux.microsoft.com>
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On Mon, Mar 20, 2023 at 08:37:56PM +0100, Jeremi Piotrowski wrote:
> Because of patch 4. My thinking was that the irq setup requires poking
> at intimate architectural details (init_irq_alloc_info etc.) so it seems
> like it fits in arch/x86.

arch/x86/platform/uv/uv_irq.c:193:      init_irq_alloc_info(&info, cpumask_of(cpu));
drivers/iommu/amd/init.c:2391:  init_irq_alloc_info(&info, NULL);

Also, what patch 4's commit message says, sounds hacky to me. A simple
driver should not need the x86_vector_domain. Especially if it is some
ACPI wrapper around the PSP hw.

But I'd leave that to tglx.

> I also drew inspiration from the sev-guest device in the arch/x86/kernel/sev.c,

Yeah, we've designed another mess there considering we already have

drivers/virt/coco/sev-guest/sev-guest.c

That sev guest thing has no place in sev.c and it should go away from
there.

> which is used in a similar context (the PSP device I am registering here is
> for SNP-host support).
> 
> Would you prefer it in drivers/platform/x86?

drivers/hv/?

Seeing how hyperv is the only thing that's going to use it, AFAICT.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette