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From f208638680e5cb4eb0d2871ce8c29a6cfbe44dce Mon Sep 17 00:00:00 2001
From: Ram Pai <linuxram@us.ibm.com>
Date: Mon, 26 Mar 2018 19:36:54 -0700
Subject: [PATCH] powerpc/mm: Fix thread_pkey_regs_init()

References: FATE#322447, bsc#1078248, git-fixes
Patch-mainline: v4.17-rc1
Git-commit: f208638680e5cb4eb0d2871ce8c29a6cfbe44dce

thread_pkey_regs_init() initializes the pkey related registers
instead of initializing the fields in the task structures.  Fortunately
those key related registers are re-set to zero when the task
gets scheduled on the cpu. However its good to fix this glaringly
visible error.

Fixes: 06bb53b33804 ("powerpc: store and restore the pkey state across context switches")
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 arch/powerpc/mm/pkeys.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c
index ba71c5481f42..328737b4d73c 100644
--- a/arch/powerpc/mm/pkeys.c
+++ b/arch/powerpc/mm/pkeys.c
@@ -308,9 +308,9 @@ void thread_pkey_regs_init(struct thread_struct *thread)
 	if (static_branch_likely(&pkey_disabled))
 		return;
 
-	write_amr(read_amr() & pkey_amr_uamor_mask);
-	write_iamr(read_iamr() & pkey_iamr_mask);
-	write_uamor(read_uamor() & pkey_amr_uamor_mask);
+	thread->amr = read_amr() & pkey_amr_uamor_mask;
+	thread->iamr = read_iamr() & pkey_iamr_mask;
+	thread->uamor = read_uamor() & pkey_amr_uamor_mask;
 }
 
 static inline bool pkey_allows_readwrite(int pkey)
-- 
2.13.6