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Patch "powerpc/pseries: Fix IBM_ARCH_VEC_NRCORES_OFFSET since POWER8NVL was added" has been added to the 4.6-stable tree

PATCH [email protected] 1 participant 1 message Jul 11, 2016

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This is a note to let you know that I've just added the patch titled

powerpc/pseries: Fix IBM_ARCH_VEC_NRCORES_OFFSET since POWER8NVL was added

to the 4.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
powerpc-pseries-fix-ibm_arch_vec_nrcores_offset-since-power8nvl-was-added.patch
and it can be found in the queue-4.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

Quoted 1 line

From 2c2a63e301fd19ccae673e79de59b30a232ff7f9 Mon Sep 17 00:00:00 2001

From: Michael Ellerman <[email protected]>
Date: Wed, 8 Jun 2016 10:01:23 +1000
Subject: powerpc/pseries: Fix IBM_ARCH_VEC_NRCORES_OFFSET since POWER8NVL was added

From: Michael Ellerman <[email protected]>

commit 2c2a63e301fd19ccae673e79de59b30a232ff7f9 upstream.

The recent commit 7cc851039d64 ("powerpc/pseries: Add POWER8NVL support to ibm,client-architecture-support call") added a new PVR mask & value to the start of the ibm_architecture_vec[] array.

However it missed the fact that further down in the array, we hard code the offset of one of the fields, and then at boot use that value to patch the value in the array. This means every update to the array must also update the #define, ugh.

This means that on pseries machines we will misreport to firmware the number of cores we support, by a factor of threads_per_core.

Fix it for now by updating the #define.

Fixes 7cc851039d64 ("powerpc/pseries: Add POWER8NVL support to ibm,client-architecture-support call")
---
 arch/powerpc/kernel/prom_init.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
arch/powerpc/kernel/prom_init.c +1 -1
@@ -719,7 +719,7 @@ unsigned char ibm_architecture_vec[] = {
 	 * must match by the macro below. Update the definition if
 	 * the structure layout changes.
 	 */
-#define IBM_ARCH_VEC_NRCORES_OFFSET	125
+#define IBM_ARCH_VEC_NRCORES_OFFSET	133
 	W(NR_CPUS),			/* number of cores supported */
 	0,
 	0,

Patches currently in stable-queue which might be from [email protected] are

queue-4.6/powerpc-pseries-fix-ibm_arch_vec_nrcores_offset-since-power8nvl-was-added.patch queue-4.6/of-fix-autoloading-due-to-broken-modalias-with-no-compatible.patch queue-4.6/powerpc-tm-always-reclaim-in-start_thread-for-exec-class-syscalls.patch queue-4.6/powerpc-iommu-remove-the-dependency-on-eeh-struct-in-ddw-mechanism.patch queue-4.6/powerpc-pseries-fix-pci-config-address-for-ddw.patch