linux-kernel - RE: [PATCH v2 06/10] x86/mce: Convert multiple if () statements into a switch() statement

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Message-ID: <SJ1PR11MB608380793D6F55A62332E0D1FC4E2@SJ1PR11MB6083.namprd11.prod.outlook.com>
Date: Thu, 24 Oct 2024 16:42:28 +0000
From: "Luck, Tony" <tony.luck@...el.com>
To: "Zhuo, Qiuxu" <qiuxu.zhuo@...el.com>, "Hansen, Dave"
	<dave.hansen@...el.com>, "Mehta, Sohil" <sohil.mehta@...el.com>
CC: "bp@...en8.de" <bp@...en8.de>, "tglx@...utronix.de" <tglx@...utronix.de>,
	"dave.hansen@...ux.intel.com" <dave.hansen@...ux.intel.com>,
	"mingo@...hat.com" <mingo@...hat.com>, "hpa@...or.com" <hpa@...or.com>,
	"x86@...nel.org" <x86@...nel.org>, "linux-edac@...r.kernel.org"
	<linux-edac@...r.kernel.org>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>
Subject: RE: [PATCH v2 06/10] x86/mce: Convert multiple if () statements into
 a switch() statement

-       if (c->x86 == 6 && c->x86_model < 0x1A && this_cpu_read(mce_num_banks) > 0)
+       if (c->x86_vfm < INTEL_NEHALEM_EP && this_cpu_read(mce_num_banks) > 0)
                mce_banks[0].init = false;

Updated code now matches for families before 6 (486, Pentium). 486 would never get
to this code. But I think from the comments about machine check bank 0 being magic
that Pentium had some rudimentary support.

Should this be:
	if (c->x86_vfm >= INTEL_PENTIUM_PRO && c->x86_vfm < INTEL_NEHALEM_EP && this_cpu_read(mce_num_banks) > 0)
to avoid this semantic change?

-       if (c->x86 == 6 && c->x86_model <= 13 && cfg->bootlog < 0)
+       if (c->x86_vfm < INTEL_CORE_YONAH && cfg->bootlog < 0)
                cfg->bootlog = 0;

Same as above. New code matches for families 4 and 5.

-Tony