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Diffstat (limited to 'arch/arm64/kvm/sys_regs.c')
-rw-r--r--arch/arm64/kvm/sys_regs.c333
1 files changed, 261 insertions, 72 deletions
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 2e070d3baf9f..1830ebc227d1 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -23,6 +23,7 @@
#include <linux/bsearch.h>
#include <linux/kvm_host.h>
#include <linux/mm.h>
+#include <linux/printk.h>
#include <linux/uaccess.h>
#include <asm/cacheflush.h>
@@ -841,13 +842,16 @@ static bool access_cntp_tval(struct kvm_vcpu *vcpu,
struct sys_reg_params *p,
const struct sys_reg_desc *r)
{
- struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
u64 now = kvm_phys_timer_read();
+ u64 cval;
- if (p->is_write)
- ptimer->cnt_cval = p->regval + now;
- else
- p->regval = ptimer->cnt_cval - now;
+ if (p->is_write) {
+ kvm_arm_timer_set_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL,
+ p->regval + now);
+ } else {
+ cval = kvm_arm_timer_get_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL);
+ p->regval = cval - now;
+ }
return true;
}
@@ -856,24 +860,10 @@ static bool access_cntp_ctl(struct kvm_vcpu *vcpu,
struct sys_reg_params *p,
const struct sys_reg_desc *r)
{
- struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
-
- if (p->is_write) {
- /* ISTATUS bit is read-only */
- ptimer->cnt_ctl = p->regval & ~ARCH_TIMER_CTRL_IT_STAT;
- } else {
- u64 now = kvm_phys_timer_read();
-
- p->regval = ptimer->cnt_ctl;
- /*
- * Set ISTATUS bit if it's expired.
- * Note that according to ARMv8 ARM Issue A.k, ISTATUS bit is
- * UNKNOWN when ENABLE bit is 0, so we chose to set ISTATUS bit
- * regardless of ENABLE bit for our implementation convenience.
- */
- if (ptimer->cnt_cval <= now)
- p->regval |= ARCH_TIMER_CTRL_IT_STAT;
- }
+ if (p->is_write)
+ kvm_arm_timer_set_reg(vcpu, KVM_REG_ARM_PTIMER_CTL, p->regval);
+ else
+ p->regval = kvm_arm_timer_get_reg(vcpu, KVM_REG_ARM_PTIMER_CTL);
return true;
}
@@ -882,16 +872,154 @@ static bool access_cntp_cval(struct kvm_vcpu *vcpu,
struct sys_reg_params *p,
const struct sys_reg_desc *r)
{
- struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
-
if (p->is_write)
- ptimer->cnt_cval = p->regval;
+ kvm_arm_timer_set_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL, p->regval);
else
- p->regval = ptimer->cnt_cval;
+ p->regval = kvm_arm_timer_get_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL);
return true;
}
+/* Read a sanitised cpufeature ID register by sys_reg_desc */
+static u64 read_id_reg(struct sys_reg_desc const *r, bool raz)
+{
+ u32 id = sys_reg((u32)r->Op0, (u32)r->Op1,
+ (u32)r->CRn, (u32)r->CRm, (u32)r->Op2);
+ u64 val = raz ? 0 : read_sanitised_ftr_reg(id);
+
+ if (id == SYS_ID_AA64PFR0_EL1) {
+ if (val & (0xfUL << ID_AA64PFR0_SVE_SHIFT))
+ pr_err_once("kvm [%i]: SVE unsupported for guests, suppressing\n",
+ task_pid_nr(current));
+
+ val &= ~(0xfUL << ID_AA64PFR0_SVE_SHIFT);
+ }
+
+ return val;
+}
+
+/* cpufeature ID register access trap handlers */
+
+static bool __access_id_reg(struct kvm_vcpu *vcpu,
+ struct sys_reg_params *p,
+ const struct sys_reg_desc *r,
+ bool raz)
+{
+ if (p->is_write)
+ return write_to_read_only(vcpu, p, r);
+
+ p->regval = read_id_reg(r, raz);
+ return true;
+}
+
+static bool access_id_reg(struct kvm_vcpu *vcpu,
+ struct sys_reg_params *p,
+ const struct sys_reg_desc *r)
+{
+ return __access_id_reg(vcpu, p, r, false);
+}
+
+static bool access_raz_id_reg(struct kvm_vcpu *vcpu,
+ struct sys_reg_params *p,
+ const struct sys_reg_desc *r)
+{
+ return __access_id_reg(vcpu, p, r, true);
+}
+
+static int reg_from_user(u64 *val, const void __user *uaddr, u64 id);
+static int reg_to_user(void __user *uaddr, const u64 *val, u64 id);
+static u64 sys_reg_to_index(const struct sys_reg_desc *reg);
+
+/*
+ * cpufeature ID register user accessors
+ *
+ * For now, these registers are immutable for userspace, so no values
+ * are stored, and for set_id_reg() we don't allow the effective value
+ * to be changed.
+ */
+static int __get_id_reg(const struct sys_reg_desc *rd, void __user *uaddr,
+ bool raz)
+{
+ const u64 id = sys_reg_to_index(rd);
+ const u64 val = read_id_reg(rd, raz);
+
+ return reg_to_user(uaddr, &val, id);
+}
+
+static int __set_id_reg(const struct sys_reg_desc *rd, void __user *uaddr,
+ bool raz)
+{
+ const u64 id = sys_reg_to_index(rd);
+ int err;
+ u64 val;
+
+ err = reg_from_user(&val, uaddr, id);
+ if (err)
+ return err;
+
+ /* This is what we mean by invariant: you can't change it. */
+ if (val != read_id_reg(rd, raz))
+ return -EINVAL;
+
+ return 0;
+}
+
+static int get_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+ const struct kvm_one_reg *reg, void __user *uaddr)
+{
+ return __get_id_reg(rd, uaddr, false);
+}
+
+static int set_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+ const struct kvm_one_reg *reg, void __user *uaddr)
+{
+ return __set_id_reg(rd, uaddr, false);
+}
+
+static int get_raz_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+ const struct kvm_one_reg *reg, void __user *uaddr)
+{
+ return __get_id_reg(rd, uaddr, true);
+}
+
+static int set_raz_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+ const struct kvm_one_reg *reg, void __user *uaddr)
+{
+ return __set_id_reg(rd, uaddr, true);
+}
+
+/* sys_reg_desc initialiser for known cpufeature ID registers */
+#define ID_SANITISED(name) { \
+ SYS_DESC(SYS_##name), \
+ .access = access_id_reg, \
+ .get_user = get_id_reg, \
+ .set_user = set_id_reg, \
+}
+
+/*
+ * sys_reg_desc initialiser for architecturally unallocated cpufeature ID
+ * register with encoding Op0=3, Op1=0, CRn=0, CRm=crm, Op2=op2
+ * (1 <= crm < 8, 0 <= Op2 < 8).
+ */
+#define ID_UNALLOCATED(crm, op2) { \
+ Op0(3), Op1(0), CRn(0), CRm(crm), Op2(op2), \
+ .access = access_raz_id_reg, \
+ .get_user = get_raz_id_reg, \
+ .set_user = set_raz_id_reg, \
+}
+
+/*
+ * sys_reg_desc initialiser for known ID registers that we hide from guests.
+ * For now, these are exposed just like unallocated ID regs: they appear
+ * RAZ for the guest.
+ */
+#define ID_HIDDEN(name) { \
+ SYS_DESC(SYS_##name), \
+ .access = access_raz_id_reg, \
+ .get_user = get_raz_id_reg, \
+ .set_user = set_raz_id_reg, \
+}
+
/*
* Architected system registers.
* Important: Must be sorted ascending by Op0, Op1, CRn, CRm, Op2
@@ -944,6 +1072,84 @@ static const struct sys_reg_desc sys_reg_descs[] = {
{ SYS_DESC(SYS_DBGVCR32_EL2), NULL, reset_val, DBGVCR32_EL2, 0 },
{ SYS_DESC(SYS_MPIDR_EL1), NULL, reset_mpidr, MPIDR_EL1 },
+
+ /*
+ * ID regs: all ID_SANITISED() entries here must have corresponding
+ * entries in arm64_ftr_regs[].
+ */
+
+ /* AArch64 mappings of the AArch32 ID registers */
+ /* CRm=1 */
+ ID_SANITISED(ID_PFR0_EL1),
+ ID_SANITISED(ID_PFR1_EL1),
+ ID_SANITISED(ID_DFR0_EL1),
+ ID_HIDDEN(ID_AFR0_EL1),
+ ID_SANITISED(ID_MMFR0_EL1),
+ ID_SANITISED(ID_MMFR1_EL1),
+ ID_SANITISED(ID_MMFR2_EL1),
+ ID_SANITISED(ID_MMFR3_EL1),
+
+ /* CRm=2 */
+ ID_SANITISED(ID_ISAR0_EL1),
+ ID_SANITISED(ID_ISAR1_EL1),
+ ID_SANITISED(ID_ISAR2_EL1),
+ ID_SANITISED(ID_ISAR3_EL1),
+ ID_SANITISED(ID_ISAR4_EL1),
+ ID_SANITISED(ID_ISAR5_EL1),
+ ID_SANITISED(ID_MMFR4_EL1),
+ ID_UNALLOCATED(2,7),
+
+ /* CRm=3 */
+ ID_SANITISED(MVFR0_EL1),
+ ID_SANITISED(MVFR1_EL1),
+ ID_SANITISED(MVFR2_EL1),
+ ID_UNALLOCATED(3,3),
+ ID_UNALLOCATED(3,4),
+ ID_UNALLOCATED(3,5),
+ ID_UNALLOCATED(3,6),
+ ID_UNALLOCATED(3,7),
+
+ /* AArch64 ID registers */
+ /* CRm=4 */
+ ID_SANITISED(ID_AA64PFR0_EL1),
+ ID_SANITISED(ID_AA64PFR1_EL1),
+ ID_UNALLOCATED(4,2),
+ ID_UNALLOCATED(4,3),
+ ID_UNALLOCATED(4,4),
+ ID_UNALLOCATED(4,5),
+ ID_UNALLOCATED(4,6),
+ ID_UNALLOCATED(4,7),
+
+ /* CRm=5 */
+ ID_SANITISED(ID_AA64DFR0_EL1),
+ ID_SANITISED(ID_AA64DFR1_EL1),
+ ID_UNALLOCATED(5,2),
+ ID_UNALLOCATED(5,3),
+ ID_HIDDEN(ID_AA64AFR0_EL1),
+ ID_HIDDEN(ID_AA64AFR1_EL1),
+ ID_UNALLOCATED(5,6),
+ ID_UNALLOCATED(5,7),
+
+ /* CRm=6 */
+ ID_SANITISED(ID_AA64ISAR0_EL1),
+ ID_SANITISED(ID_AA64ISAR1_EL1),
+ ID_UNALLOCATED(6,2),
+ ID_UNALLOCATED(6,3),
+ ID_UNALLOCATED(6,4),
+ ID_UNALLOCATED(6,5),
+ ID_UNALLOCATED(6,6),
+ ID_UNALLOCATED(6,7),
+
+ /* CRm=7 */
+ ID_SANITISED(ID_AA64MMFR0_EL1),
+ ID_SANITISED(ID_AA64MMFR1_EL1),
+ ID_SANITISED(ID_AA64MMFR2_EL1),
+ ID_UNALLOCATED(7,3),
+ ID_UNALLOCATED(7,4),
+ ID_UNALLOCATED(7,5),
+ ID_UNALLOCATED(7,6),
+ ID_UNALLOCATED(7,7),
+
{ SYS_DESC(SYS_SCTLR_EL1), access_vm_reg, reset_val, SCTLR_EL1, 0x00C50078 },
{ SYS_DESC(SYS_CPACR_EL1), NULL, reset_val, CPACR_EL1, 0 },
{ SYS_DESC(SYS_TTBR0_EL1), access_vm_reg, reset_unknown, TTBR0_EL1 },
@@ -1790,8 +1996,8 @@ static const struct sys_reg_desc *index_to_sys_reg_desc(struct kvm_vcpu *vcpu,
if (!r)
r = find_reg(&params, sys_reg_descs, ARRAY_SIZE(sys_reg_descs));
- /* Not saved in the sys_reg array? */
- if (r && !r->reg)
+ /* Not saved in the sys_reg array and not otherwise accessible? */
+ if (r && !(r->reg || r->get_user))
r = NULL;
return r;
@@ -1815,20 +2021,6 @@ static const struct sys_reg_desc *index_to_sys_reg_desc(struct kvm_vcpu *vcpu,
FUNCTION_INVARIANT(midr_el1)
FUNCTION_INVARIANT(ctr_el0)
FUNCTION_INVARIANT(revidr_el1)
-FUNCTION_INVARIANT(id_pfr0_el1)
-FUNCTION_INVARIANT(id_pfr1_el1)
-FUNCTION_INVARIANT(id_dfr0_el1)
-FUNCTION_INVARIANT(id_afr0_el1)
-FUNCTION_INVARIANT(id_mmfr0_el1)
-FUNCTION_INVARIANT(id_mmfr1_el1)
-FUNCTION_INVARIANT(id_mmfr2_el1)
-FUNCTION_INVARIANT(id_mmfr3_el1)
-FUNCTION_INVARIANT(id_isar0_el1)
-FUNCTION_INVARIANT(id_isar1_el1)
-FUNCTION_INVARIANT(id_isar2_el1)
-FUNCTION_INVARIANT(id_isar3_el1)
-FUNCTION_INVARIANT(id_isar4_el1)
-FUNCTION_INVARIANT(id_isar5_el1)
FUNCTION_INVARIANT(clidr_el1)
FUNCTION_INVARIANT(aidr_el1)
@@ -1836,20 +2028,6 @@ FUNCTION_INVARIANT(aidr_el1)
static struct sys_reg_desc invariant_sys_regs[] = {
{ SYS_DESC(SYS_MIDR_EL1), NULL, get_midr_el1 },
{ SYS_DESC(SYS_REVIDR_EL1), NULL, get_revidr_el1 },
- { SYS_DESC(SYS_ID_PFR0_EL1), NULL, get_id_pfr0_el1 },
- { SYS_DESC(SYS_ID_PFR1_EL1), NULL, get_id_pfr1_el1 },
- { SYS_DESC(SYS_ID_DFR0_EL1), NULL, get_id_dfr0_el1 },
- { SYS_DESC(SYS_ID_AFR0_EL1), NULL, get_id_afr0_el1 },
- { SYS_DESC(SYS_ID_MMFR0_EL1), NULL, get_id_mmfr0_el1 },
- { SYS_DESC(SYS_ID_MMFR1_EL1), NULL, get_id_mmfr1_el1 },
- { SYS_DESC(SYS_ID_MMFR2_EL1), NULL, get_id_mmfr2_el1 },
- { SYS_DESC(SYS_ID_MMFR3_EL1), NULL, get_id_mmfr3_el1 },
- { SYS_DESC(SYS_ID_ISAR0_EL1), NULL, get_id_isar0_el1 },
- { SYS_DESC(SYS_ID_ISAR1_EL1), NULL, get_id_isar1_el1 },
- { SYS_DESC(SYS_ID_ISAR2_EL1), NULL, get_id_isar2_el1 },
- { SYS_DESC(SYS_ID_ISAR3_EL1), NULL, get_id_isar3_el1 },
- { SYS_DESC(SYS_ID_ISAR4_EL1), NULL, get_id_isar4_el1 },
- { SYS_DESC(SYS_ID_ISAR5_EL1), NULL, get_id_isar5_el1 },
{ SYS_DESC(SYS_CLIDR_EL1), NULL, get_clidr_el1 },
{ SYS_DESC(SYS_AIDR_EL1), NULL, get_aidr_el1 },
{ SYS_DESC(SYS_CTR_EL0), NULL, get_ctr_el0 },
@@ -2079,12 +2257,31 @@ static bool copy_reg_to_user(const struct sys_reg_desc *reg, u64 __user **uind)
return true;
}
+static int walk_one_sys_reg(const struct sys_reg_desc *rd,
+ u64 __user **uind,
+ unsigned int *total)
+{
+ /*
+ * Ignore registers we trap but don't save,
+ * and for which no custom user accessor is provided.
+ */
+ if (!(rd->reg || rd->get_user))
+ return 0;
+
+ if (!copy_reg_to_user(rd, uind))
+ return -EFAULT;
+
+ (*total)++;
+ return 0;
+}
+
/* Assumed ordered tables, see kvm_sys_reg_table_init. */
static int walk_sys_regs(struct kvm_vcpu *vcpu, u64 __user *uind)
{
const struct sys_reg_desc *i1, *i2, *end1, *end2;
unsigned int total = 0;
size_t num;
+ int err;
/* We check for duplicates here, to allow arch-specific overrides. */
i1 = get_target_table(vcpu->arch.target, true, &num);
@@ -2098,21 +2295,13 @@ static int walk_sys_regs(struct kvm_vcpu *vcpu, u64 __user *uind)
while (i1 || i2) {
int cmp = cmp_sys_reg(i1, i2);
/* target-specific overrides generic entry. */
- if (cmp <= 0) {
- /* Ignore registers we trap but don't save. */
- if (i1->reg) {
- if (!copy_reg_to_user(i1, &uind))
- return -EFAULT;
- total++;
- }
- } else {
- /* Ignore registers we trap but don't save. */
- if (i2->reg) {
- if (!copy_reg_to_user(i2, &uind))
- return -EFAULT;
- total++;
- }
- }
+ if (cmp <= 0)
+ err = walk_one_sys_reg(i1, &uind, &total);
+ else
+ err = walk_one_sys_reg(i2, &uind, &total);
+
+ if (err)
+ return err;
if (cmp <= 0 && ++i1 == end1)
i1 = NULL;
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-22 03:45:49 +0100