From d222af072380c4470295c07d84ecb15f4937e365 Mon Sep 17 00:00:00 2001
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Wed, 6 Sep 2017 15:20:55 +1000
Subject: [PATCH] KVM: PPC: Book3S HV: Don't access XIVE PIPR register using
byte accesses
References: bsc#1061840
Patch-mainline: v4.14-rc1
Git-commit: d222af072380c4470295c07d84ecb15f4937e365
The XIVE interrupt controller on POWER9 machines doesn't support byte
accesses to any register in the thread management area other than the
CPPR (current processor priority register). In particular, when
reading the PIPR (pending interrupt priority register), we need to
do a 32-bit or 64-bit load.
Cc: stable@vger.kernel.org # v4.13
Fixes: 2c4fb78f78b6 ("KVM: PPC: Book3S HV: Workaround POWER9 DD1.0 bug causing IPB bit loss")
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/kvm/book3s_hv_rm_xive.c | 1 -
arch/powerpc/kvm/book3s_xive.c | 1 -
arch/powerpc/kvm/book3s_xive_template.c | 7 ++++---
3 files changed, 4 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_hv_rm_xive.c b/arch/powerpc/kvm/book3s_hv_rm_xive.c
index abf5f01b6eb1..5b81a807d742 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_xive.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_xive.c
@@ -38,7 +38,6 @@ static inline void __iomem *get_tima_phys(void)
#define __x_tima get_tima_phys()
#define __x_eoi_page(xd) ((void __iomem *)((xd)->eoi_page))
#define __x_trig_page(xd) ((void __iomem *)((xd)->trig_page))
-#define __x_readb __raw_rm_readb
#define __x_writeb __raw_rm_writeb
#define __x_readw __raw_rm_readw
#define __x_readq __raw_rm_readq
diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c
index 08b200a0bbce..13304622ab1c 100644
--- a/arch/powerpc/kvm/book3s_xive.c
+++ b/arch/powerpc/kvm/book3s_xive.c
@@ -48,7 +48,6 @@
#define __x_tima xive_tima
#define __x_eoi_page(xd) ((void __iomem *)((xd)->eoi_mmio))
#define __x_trig_page(xd) ((void __iomem *)((xd)->trig_mmio))
-#define __x_readb __raw_readb
#define __x_writeb __raw_writeb
#define __x_readw __raw_readw
#define __x_readq __raw_readq
diff --git a/arch/powerpc/kvm/book3s_xive_template.c b/arch/powerpc/kvm/book3s_xive_template.c
index d1ed2c41b5d2..c7a5deadd1cc 100644
--- a/arch/powerpc/kvm/book3s_xive_template.c
+++ b/arch/powerpc/kvm/book3s_xive_template.c
@@ -28,7 +28,8 @@ static void GLUE(X_PFX,ack_pending)(struct kvmppc_xive_vcpu *xc)
* bit.
*/
if (cpu_has_feature(CPU_FTR_POWER9_DD1)) {
- u8 pipr = __x_readb(__x_tima + TM_QW1_OS + TM_PIPR);
+ __be64 qw1 = __x_readq(__x_tima + TM_QW1_OS);
+ u8 pipr = be64_to_cpu(qw1) & 0xff;
if (pipr >= xc->hw_cppr)
return;
}
@@ -336,7 +337,6 @@ X_STATIC unsigned long GLUE(X_PFX,h_ipoll)(struct kvm_vcpu *vcpu, unsigned long
struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
u8 pending = xc->pending;
u32 hirq;
- u8 pipr;
pr_devel("H_IPOLL(server=%ld)\n", server);
@@ -353,7 +353,8 @@ X_STATIC unsigned long GLUE(X_PFX,h_ipoll)(struct kvm_vcpu *vcpu, unsigned long
pending = 0xff;
} else {
/* Grab pending interrupt if any */
- pipr = __x_readb(__x_tima + TM_QW1_OS + TM_PIPR);
+ __be64 qw1 = __x_readq(__x_tima + TM_QW1_OS);
+ u8 pipr = be64_to_cpu(qw1) & 0xff;
if (pipr < 8)
pending |= 1 << pipr;
}
--
2.10.2