From: Christoffer Dall <[email protected]>
commit 240e99cbd00aa541b572480e3ea7ecb0d480bc79 upstream.
Fixes booting a guest OS on a v3.10 host kernel.
Without this, on an arndale board, qemu bails with:
Initial read of kernel register state failed
kvm_init_vcpu failed: Invalid argument
Signed-off-by: Christoffer Dall <[email protected]>
Signed-off-by: Kim Phillips <[email protected]>
Cc: Gleb Natapov <[email protected]>
Cc: Paolo Bonzini <[email protected]>
Cc: Russell King <[email protected]>
Cc: Jonghwan Choi <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: <[email protected]> # 3.10.x
---
resumbission of:
https://lkml.org/lkml/2013/8/23/50
albeit with perhaps a better rationale than 'looks like it should be in
the 3.10-stable tree'.
arch/arm/kvm/coproc.c | 26 +++++++++++++++++++-------
arch/arm/kvm/coproc.h | 3 +++
arch/arm/kvm/coproc_a15.c | 6 +++++-
3 files changed, 27 insertions(+), 8 deletions(-)
diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c
index 4a51990..db9cf69 100644
--- a/arch/arm/kvm/coproc.c
+++ b/arch/arm/kvm/coproc.c
@@ -146,7 +146,11 @@ static bool pm_fake(struct kvm_vcpu *vcpu,
#define access_pmintenclr pm_fake
/* Architected CP15 registers.
- * Important: Must be sorted ascending by CRn, CRM, Op1, Op2
+ * CRn denotes the primary register number, but is copied to the CRm in the
+ * user space API for 64-bit register access in line with the terminology used
+ * in the ARM ARM.
+ * Important: Must be sorted ascending by CRn, CRM, Op1, Op2 and with 64-bit
+ * registers preceding 32-bit ones.
*/
static const struct coproc_reg cp15_regs[] = {
/* CSSELR: swapped by interrupt.S. */
@@ -154,8 +158,8 @@ static const struct coproc_reg cp15_regs[] = {
NULL, reset_unknown, c0_CSSELR },
/* TTBR0/TTBR1: swapped by interrupt.S. */
- { CRm( 2), Op1( 0), is64, NULL, reset_unknown64, c2_TTBR0 },
- { CRm( 2), Op1( 1), is64, NULL, reset_unknown64, c2_TTBR1 },
+ { CRm64( 2), Op1( 0), is64, NULL, reset_unknown64, c2_TTBR0 },
+ { CRm64( 2), Op1( 1), is64, NULL, reset_unknown64, c2_TTBR1 },
/* TTBCR: swapped by interrupt.S. */
{ CRn( 2), CRm( 0), Op1( 0), Op2( 2), is32,
@@ -182,7 +186,7 @@ static const struct coproc_reg cp15_regs[] = {
NULL, reset_unknown, c6_IFAR },
/* PAR swapped by interrupt.S */
- { CRn( 7), Op1( 0), is64, NULL, reset_unknown64, c7_PAR },
+ { CRm64( 7), Op1( 0), is64, NULL, reset_unknown64, c7_PAR },
/*
* DC{C,I,CI}SW operations:
@@ -399,12 +403,13 @@ static bool index_to_params(u64 id, struct coproc_params *params)
| KVM_REG_ARM_OPC1_MASK))
return false;
params->is_64bit = true;
- params->CRm = ((id & KVM_REG_ARM_CRM_MASK)
+ /* CRm to CRn: see cp15_to_index for details */
+ params->CRn = ((id & KVM_REG_ARM_CRM_MASK)
>> KVM_REG_ARM_CRM_SHIFT);
params->Op1 = ((id & KVM_REG_ARM_OPC1_MASK)
>> KVM_REG_ARM_OPC1_SHIFT);
params->Op2 = 0;
- params->CRn = 0;
+ params->CRm = 0;
return true;
default:
return false;
@@ -898,7 +903,14 @@ static u64 cp15_to_index(const struct coproc_reg *reg)
if (reg->is_64) {
val |= KVM_REG_SIZE_U64;
val |= (reg->Op1 << KVM_REG_ARM_OPC1_SHIFT);
- val |= (reg->CRm << KVM_REG_ARM_CRM_SHIFT);
+ /*
+ * CRn always denotes the primary coproc. reg. nr. for the
+ * in-kernel representation, but the user space API uses the
+ * CRm for the encoding, because it is modelled after the
+ * MRRC/MCRR instructions: see the ARM ARM rev. c page
+ * B3-1445
+ */
+ val |= (reg->CRn << KVM_REG_ARM_CRM_SHIFT);
} else {
val |= KVM_REG_SIZE_U32;
val |= (reg->Op1 << KVM_REG_ARM_OPC1_SHIFT);
diff --git a/arch/arm/kvm/coproc.h b/arch/arm/kvm/coproc.h
index b7301d3..0461d5c 100644
--- a/arch/arm/kvm/coproc.h
+++ b/arch/arm/kvm/coproc.h
@@ -135,6 +135,8 @@ static inline int cmp_reg(const struct coproc_reg *i1,
return -1;
if (i1->CRn != i2->CRn)
return i1->CRn - i2->CRn;
+ if (i1->is_64 != i2->is_64)
+ return i2->is_64 - i1->is_64;
if (i1->CRm != i2->CRm)
return i1->CRm - i2->CRm;
if (i1->Op1 != i2->Op1)
@@ -145,6 +147,7 @@ static inline int cmp_reg(const struct coproc_reg *i1,
#define CRn(_x) .CRn = _x
#define CRm(_x) .CRm = _x
+#define CRm64(_x) .CRn = _x, .CRm = 0
#define Op1(_x) .Op1 = _x
#define Op2(_x) .Op2 = _x
#define is64 .is_64 = true
diff --git a/arch/arm/kvm/coproc_a15.c b/arch/arm/kvm/coproc_a15.c
index 685063a..cf93472 100644
--- a/arch/arm/kvm/coproc_a15.c
+++ b/arch/arm/kvm/coproc_a15.c
@@ -114,7 +114,11 @@ static bool access_l2ectlr(struct kvm_vcpu *vcpu,
/*
* A15-specific CP15 registers.
- * Important: Must be sorted ascending by CRn, CRM, Op1, Op2
+ * CRn denotes the primary register number, but is copied to the CRm in the
+ * user space API for 64-bit register access in line with the terminology used
+ * in the ARM ARM.
+ * Important: Must be sorted ascending by CRn, CRM, Op1, Op2 and with 64-bit
+ * registers preceding 32-bit ones.
*/
static const struct coproc_reg a15_regs[] = {
/* MPIDR: we use VMPIDR for guest access. */
--
1.8.4