Commit 0422b07b authored by Yazen Ghannam's avatar Yazen Ghannam Committed by Borislav Petkov (AMD)
Browse files

x86/mce/amd: Filter bogus hardware errors on Zen3 clients

Users have been observing multiple L3 cache deferred errors after recent
kernel rework of deferred error handling.¹ ⁴

The errors are bogus due to inconsistent status values. Also, user verified
that bogus MCA_DESTAT values are present on the system even with an older
kernel.²

The errors seem to be garbage values present in the MCA_DESTAT of some L3
cache banks. These were implicitly ignored before the recent kernel rework
because these do not generate a deferred error interrupt.

A later revision of the rework patch was merged for v6.19. This naturally
filtered out most of the bogus error logs. However, a few signatures still
remain.³

Minimize the scope of the filter to the reported CPU
family/model/stepping and only for errors which don't have the Enabled
bit in the MCi status MSR.

¹ https://lore.kernel.org/20250915010010.3547-1-spasswolf@web.de
² https://lore.kernel.org/6e1eda7dd55f6fa30405edf7b0f75695cf55b237.camel@web.de
³ https://lore.kernel.org/21ba47fa8893b33b94370c2a42e5084cf0d2e975.camel@web.dehttps://lore.kernel.org/r/CAKFB093B2k3sKsGJ_QNX1jVQsaXVFyy=wNwpzCGLOXa_vSDwXw@mail.gmail.com

  [ bp: Generalize the condition according to which errors are bogus. ]

Fixes: 7cb735d7 ("x86/mce: Unify AMD DFR handler with MCA Polling")
Closes: https://lore.kernel.org/20250915010010.3547-1-spasswolf@web.de


Reported-by: default avatarBert Karwatzki <spasswolf@web.de>
Signed-off-by: default avatarYazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: default avatarMario Limonciello <mario.limonciello@amd.com>
Tested-By: default avatarBert Karwatzki <spasswolf@web.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/20250915010010.3547-1-spasswolf@web.de
parent 7aaa8047
Loading
Loading
Loading
Loading
+8 −0
Original line number Diff line number Diff line
@@ -604,6 +604,14 @@ bool amd_filter_mce(struct mce *m)
	enum smca_bank_types bank_type = smca_get_bank_type(m->extcpu, m->bank);
	struct cpuinfo_x86 *c = &boot_cpu_data;

	/* Bogus hw errors on Cezanne A0. */
	if (c->x86 == 0x19 &&
	    c->x86_model == 0x50 &&
	    c->x86_stepping == 0x0) {
		if (!(m->status & MCI_STATUS_EN))
			return true;
	}

	/* See Family 17h Models 10h-2Fh Erratum #1114. */
	if (c->x86 == 0x17 &&
	    c->x86_model >= 0x10 && c->x86_model <= 0x2F &&