linux-kernel - [PATCH V2] x86, microcode, AMD: Fix patch level reporting for family15h

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Date:	Wed, 29 Sep 2010 19:27:12 -0500
From:	<suravee.suthikulpanit@....com>
To:	<herrmann.der.user@...glemail.com>
CC:	<bp@...en8.de>, <jacob.w.shin@...il.com>,
	<linux-kernel@...r.kernel.org>, <x86@...nel.org>,
	Suravee Suthikulpanit <suravee.suthikulpanit@....com>
Subject: [PATCH V2] x86, microcode, AMD: Fix patch level reporting for family15h

From: Suravee Suthikulpanit <suravee.suthikulpanit@....com>

On AMD family15h, applying microcode patch on the a core (core0)
would also affect the other core (core1) in the same compute unit.
The driver would skip applying the patch on core1, but it still
need to update kernel structures to reflect the proper patch level.

The current logic is not updating the struct ucode_cpu_info.cpu_sig.rev
of the skipped core. This causes the /sys/devices/system/cpu/cpu1/microcode/version
to report incorrect patch level as shown below:

$ grep . cpu?/microcode/version
cpu0/microcode/version:0x600063d
cpu1/microcode/version:0x6000626
cpu2/microcode/version:0x600063d
cpu3/microcode/version:0x6000626
cpu4/microcode/version:0x600063d

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@....com>
---
Changes from V1:
	- Update commit log as suggested by Boris.

 arch/x86/kernel/microcode_amd.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 7123b5d..af99f71 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -216,6 +216,7 @@ int apply_microcode_amd(int cpu)
 	/* need to apply patch? */
 	if (rev >= mc_amd->hdr.patch_id) {
 		c->microcode = rev;
+		uci->cpu_sig.rev = rev;
 		return 0;
 	}

-- 
1.8.1.2

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