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Date:   Fri, 19 Aug 2022 20:29:47 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     "Kani, Toshi" <toshi.kani@hpe.com>
Cc:     Justin He <Justin.He@arm.com>,
        "linux-acpi@vger.kernel.org" <linux-acpi@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-edac@vger.kernel.org" <linux-edac@vger.kernel.org>,
        "devel@acpica.org" <devel@acpica.org>,
        "Rafael J . Wysocki" <rafael@kernel.org>,
        Shuai Xue <xueshuai@linux.alibaba.com>,
        Jarkko Sakkinen <jarkko@kernel.org>,
        "linux-efi@vger.kernel.org" <linux-efi@vger.kernel.org>,
        nd <nd@arm.com>, Ard Biesheuvel <ardb@kernel.org>,
        Len Brown <lenb@kernel.org>, James Morse <James.Morse@arm.com>,
        Tony Luck <tony.luck@intel.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Robert Richter <rric@kernel.org>,
        Robert Moore <robert.moore@intel.com>,
        Qiuxu Zhuo <qiuxu.zhuo@intel.com>,
        Yazen Ghannam <yazen.ghannam@amd.com>
Subject: Re: [PATCH v2 5/7] EDAC/ghes: Prevent chipset-specific edac from
 loading after ghes_edac is registered
Message-ID: <Yv/Wm/Zf0kdGgT33@zn.tnic>
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On Fri, Aug 19, 2022 at 05:48:39PM +0000, Kani, Toshi wrote:
> This flag is a static variable, say ghes_present, which is set to
> false initially. ghes_probe() sets it to true. ghes_edac_preferred()
> (aka. ghes_get_device) checks this flag at beginning and returns false
> if this flag is false. It does not get unlatched since ACPI GHES table
> is static.

What is that flag needed for at all?

There are two possibilities:

1. ghes_probe() succeeds. ghes_edac loads properly and other drivers use
ghes_get_devices() to know when to load.

2. ghes_probe() fails and that is caught during platform testing of all
those platforms who wish to use ghes_edac. BIOS is fixed and goto 1.

No need for funky flags whatsoever.

-- 
Regards/Gruss,
    Boris.

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