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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Mon, 11 Mar 2024 18:12:54 -0700
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Subject: Re: [GIT PULL] EDAC updates for v6.9
To: Borislav Petkov <bp@alien8.de>
Cc: x86-ml <x86@kernel.org>, lkml <linux-kernel@vger.kernel.org>, 
	linux-edac <linux-edac@vger.kernel.org>
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On Mon, 11 Mar 2024 at 08:57, Borislav Petkov <bp@alien8.de> wrote:
>
> -       return topology_die_id(err->cpu) % amd_get_nodes_per_socket();
> +       return topology_amd_node_id(err->cpu) % topology_amd_nodes_per_pkg();

Ho humm. Lookie here:

    static inline unsigned int topology_amd_nodes_per_pkg(void)
    { return 0; };

that's the UP case.

Yeah, I'm assuming nobody tests this for UP, but it's clearly wrong to
potentially do that modulus by zero.

So I made the merge also change that UP case of
topology_amd_nodes_per_pkg() to return 1.

Because dammit, not only is a mod-by-zero wrong, a UP system most
definitely has one node per package, not zero.

               Linus