linux-kernel - [PATCH 4.4 148/312] powerpc/book3s: Fix MCE console messages for unrecoverable MCE.

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Date:   Fri,  8 May 2020 14:32:19 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Mahesh Salgaonkar <mahesh@...ux.vnet.ibm.com>,
        Michael Ellerman <mpe@...erman.id.au>
Subject: [PATCH 4.4 148/312] powerpc/book3s: Fix MCE console messages for unrecoverable MCE.

From: Mahesh Salgaonkar <mahesh@...ux.vnet.ibm.com>

commit c74dd88e77d3ecbc9e55c78796d82c9aa21cabad upstream.

When machine check occurs with MSR(RI=0), it means MC interrupt is
unrecoverable and kernel goes down to panic path. But the console
message still shows it as recovered. This patch fixes the MCE console
messages.

Fixes: 36df96f8acaf ("powerpc/book3s: Decode and save machine check event.")
Signed-off-by: Mahesh Salgaonkar <mahesh@...ux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@...erman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 arch/powerpc/kernel/mce.c             |    3 ++-
 arch/powerpc/platforms/powernv/opal.c |    1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

--- a/arch/powerpc/kernel/mce.c
+++ b/arch/powerpc/kernel/mce.c
@@ -92,7 +92,8 @@ void save_mce_event(struct pt_regs *regs
 	mce->in_use = 1;
 
 	mce->initiator = MCE_INITIATOR_CPU;
-	if (handled)
+	/* Mark it recovered if we have handled it and MSR(RI=1). */
+	if (handled && (regs->msr & MSR_RI))
 		mce->disposition = MCE_DISPOSITION_RECOVERED;
 	else
 		mce->disposition = MCE_DISPOSITION_NOT_RECOVERED;
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -401,6 +401,7 @@ static int opal_recover_mce(struct pt_re
 
 	if (!(regs->msr & MSR_RI)) {
 		/* If MSR_RI isn't set, we cannot recover */
+		pr_err("Machine check interrupt unrecoverable: MSR(RI=0)\n");
 		recovered = 0;
 	} else if (evt->disposition == MCE_DISPOSITION_RECOVERED) {
 		/* Platform corrected itself */