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From eadce3b48b5a8ffec7c8abbd4950a501c91d2515 Mon Sep 17 00:00:00 2001
From: Nicholas Piggin <npiggin@gmail.com>
Date: Fri, 18 May 2018 03:49:43 +1000
Subject: [PATCH] KVM: PPC: Book3S HV: Fix kvmppc_bad_host_intr for real mode
 interrupts

References: bsc#1061840
Patch-mainline: v4.18-rc1
Git-commit: eadce3b48b5a8ffec7c8abbd4950a501c91d2515

When CONFIG_RELOCATABLE=n, the Linux real mode interrupt handlers call
into KVM using real address. This needs to be translated to the kernel
linear effective address before the MMU is switched on.

kvmppc_bad_host_intr misses adding these bits, so when it is used to
handle a system reset interrupt (that always gets delivered in real
mode), it results in an instruction access fault immediately after
the MMU is turned on.

Fix this by ensuring the top 2 address bits are set when the MMU is
turned on.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 arch/powerpc/kvm/book3s_hv_rmhandlers.S | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index ef9e665fc8e2..5e6e493e065e 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -3568,6 +3568,8 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX)
 	bcl	20, 31, .+4
 5:	mflr	r3
 	addi	r3, r3, 9f - 5b
+	li	r4, -1
+	rldimi	r3, r4, 62, 0	/* ensure 0xc000000000000000 bits are set */
 	ld	r4, PACAKMSR(r13)
 	mtspr	SPRN_SRR0, r3
 	mtspr	SPRN_SRR1, r4
-- 
2.13.7