OpenCloudOS-Kernel/arch/arm64/kvm/guest.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2012,2013 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* Derived from arch/arm/kvm/guest.c:
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
* Author: Christoffer Dall <c.dall@virtualopensystems.com>
*/
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
#include <linux/bits.h>
#include <linux/errno.h>
#include <linux/err.h>
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
#include <linux/nospec.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <kvm/arm_psci.h>
#include <asm/cputype.h>
#include <linux/uaccess.h>
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
#include <asm/fpsimd.h>
#include <asm/kvm.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_coproc.h>
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
#include <asm/kvm_host.h>
#include <asm/sigcontext.h>
#include "trace.h"
#define VM_STAT(x) { #x, offsetof(struct kvm, stat.x), KVM_STAT_VM }
#define VCPU_STAT(x) { #x, offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU }
struct kvm_stats_debugfs_item debugfs_entries[] = {
VCPU_STAT(hvc_exit_stat),
VCPU_STAT(wfe_exit_stat),
VCPU_STAT(wfi_exit_stat),
VCPU_STAT(mmio_exit_user),
VCPU_STAT(mmio_exit_kernel),
VCPU_STAT(exits),
{ NULL }
};
int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
{
return 0;
}
static bool core_reg_offset_is_vreg(u64 off)
{
return off >= KVM_REG_ARM_CORE_REG(fp_regs.vregs) &&
off < KVM_REG_ARM_CORE_REG(fp_regs.fpsr);
}
static u64 core_reg_offset_from_id(u64 id)
{
return id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE);
}
KVM: arm64: Filter out invalid core register IDs in KVM_GET_REG_LIST Since commit d26c25a9d19b ("arm64: KVM: Tighten guest core register access from userspace"), KVM_{GET,SET}_ONE_REG rejects register IDs that do not correspond to a single underlying architectural register. KVM_GET_REG_LIST was not changed to match however: instead, it simply yields a list of 32-bit register IDs that together cover the whole kvm_regs struct. This means that if userspace tries to use the resulting list of IDs directly to drive calls to KVM_*_ONE_REG, some of those calls will now fail. This was not the intention. Instead, iterating KVM_*_ONE_REG over the list of IDs returned by KVM_GET_REG_LIST should be guaranteed to work. This patch fixes the problem by splitting validate_core_offset() into a backend core_reg_size_from_offset() which does all of the work except for checking that the size field in the register ID matches, and kvm_arm_copy_reg_indices() and num_core_regs() are converted to use this to enumerate the valid offsets. kvm_arm_copy_reg_indices() now also sets the register ID size field appropriately based on the value returned, so the register ID supplied to userspace is fully qualified for use with the register access ioctls. Cc: stable@vger.kernel.org Fixes: d26c25a9d19b ("arm64: KVM: Tighten guest core register access from userspace") Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Tested-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-06-12 20:44:49 +08:00
static int core_reg_size_from_offset(const struct kvm_vcpu *vcpu, u64 off)
{
int size;
switch (off) {
case KVM_REG_ARM_CORE_REG(regs.regs[0]) ...
KVM_REG_ARM_CORE_REG(regs.regs[30]):
case KVM_REG_ARM_CORE_REG(regs.sp):
case KVM_REG_ARM_CORE_REG(regs.pc):
case KVM_REG_ARM_CORE_REG(regs.pstate):
case KVM_REG_ARM_CORE_REG(sp_el1):
case KVM_REG_ARM_CORE_REG(elr_el1):
case KVM_REG_ARM_CORE_REG(spsr[0]) ...
KVM_REG_ARM_CORE_REG(spsr[KVM_NR_SPSR - 1]):
size = sizeof(__u64);
break;
case KVM_REG_ARM_CORE_REG(fp_regs.vregs[0]) ...
KVM_REG_ARM_CORE_REG(fp_regs.vregs[31]):
size = sizeof(__uint128_t);
break;
case KVM_REG_ARM_CORE_REG(fp_regs.fpsr):
case KVM_REG_ARM_CORE_REG(fp_regs.fpcr):
size = sizeof(__u32);
break;
default:
return -EINVAL;
}
KVM: arm64: Filter out invalid core register IDs in KVM_GET_REG_LIST Since commit d26c25a9d19b ("arm64: KVM: Tighten guest core register access from userspace"), KVM_{GET,SET}_ONE_REG rejects register IDs that do not correspond to a single underlying architectural register. KVM_GET_REG_LIST was not changed to match however: instead, it simply yields a list of 32-bit register IDs that together cover the whole kvm_regs struct. This means that if userspace tries to use the resulting list of IDs directly to drive calls to KVM_*_ONE_REG, some of those calls will now fail. This was not the intention. Instead, iterating KVM_*_ONE_REG over the list of IDs returned by KVM_GET_REG_LIST should be guaranteed to work. This patch fixes the problem by splitting validate_core_offset() into a backend core_reg_size_from_offset() which does all of the work except for checking that the size field in the register ID matches, and kvm_arm_copy_reg_indices() and num_core_regs() are converted to use this to enumerate the valid offsets. kvm_arm_copy_reg_indices() now also sets the register ID size field appropriately based on the value returned, so the register ID supplied to userspace is fully qualified for use with the register access ioctls. Cc: stable@vger.kernel.org Fixes: d26c25a9d19b ("arm64: KVM: Tighten guest core register access from userspace") Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Tested-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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if (!IS_ALIGNED(off, size / sizeof(__u32)))
return -EINVAL;
/*
* The KVM_REG_ARM64_SVE regs must be used instead of
* KVM_REG_ARM_CORE for accessing the FPSIMD V-registers on
* SVE-enabled vcpus:
*/
if (vcpu_has_sve(vcpu) && core_reg_offset_is_vreg(off))
return -EINVAL;
KVM: arm64: Filter out invalid core register IDs in KVM_GET_REG_LIST Since commit d26c25a9d19b ("arm64: KVM: Tighten guest core register access from userspace"), KVM_{GET,SET}_ONE_REG rejects register IDs that do not correspond to a single underlying architectural register. KVM_GET_REG_LIST was not changed to match however: instead, it simply yields a list of 32-bit register IDs that together cover the whole kvm_regs struct. This means that if userspace tries to use the resulting list of IDs directly to drive calls to KVM_*_ONE_REG, some of those calls will now fail. This was not the intention. Instead, iterating KVM_*_ONE_REG over the list of IDs returned by KVM_GET_REG_LIST should be guaranteed to work. This patch fixes the problem by splitting validate_core_offset() into a backend core_reg_size_from_offset() which does all of the work except for checking that the size field in the register ID matches, and kvm_arm_copy_reg_indices() and num_core_regs() are converted to use this to enumerate the valid offsets. kvm_arm_copy_reg_indices() now also sets the register ID size field appropriately based on the value returned, so the register ID supplied to userspace is fully qualified for use with the register access ioctls. Cc: stable@vger.kernel.org Fixes: d26c25a9d19b ("arm64: KVM: Tighten guest core register access from userspace") Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Tested-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-06-12 20:44:49 +08:00
return size;
}
static int validate_core_offset(const struct kvm_vcpu *vcpu,
const struct kvm_one_reg *reg)
{
u64 off = core_reg_offset_from_id(reg->id);
int size = core_reg_size_from_offset(vcpu, off);
if (size < 0)
return -EINVAL;
if (KVM_REG_SIZE(reg->id) != size)
return -EINVAL;
return 0;
}
static int get_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
/*
* Because the kvm_regs structure is a mix of 32, 64 and
* 128bit fields, we index it as if it was a 32bit
* array. Hence below, nr_regs is the number of entries, and
* off the index in the "array".
*/
__u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
struct kvm_regs *regs = vcpu_gp_regs(vcpu);
int nr_regs = sizeof(*regs) / sizeof(__u32);
u32 off;
/* Our ID is an index into the kvm_regs struct. */
off = core_reg_offset_from_id(reg->id);
if (off >= nr_regs ||
(off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
return -ENOENT;
if (validate_core_offset(vcpu, reg))
return -EINVAL;
if (copy_to_user(uaddr, ((u32 *)regs) + off, KVM_REG_SIZE(reg->id)))
return -EFAULT;
return 0;
}
static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
__u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
struct kvm_regs *regs = vcpu_gp_regs(vcpu);
int nr_regs = sizeof(*regs) / sizeof(__u32);
__uint128_t tmp;
void *valp = &tmp;
u64 off;
int err = 0;
/* Our ID is an index into the kvm_regs struct. */
off = core_reg_offset_from_id(reg->id);
if (off >= nr_regs ||
(off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
return -ENOENT;
if (validate_core_offset(vcpu, reg))
return -EINVAL;
if (KVM_REG_SIZE(reg->id) > sizeof(tmp))
return -EINVAL;
if (copy_from_user(valp, uaddr, KVM_REG_SIZE(reg->id))) {
err = -EFAULT;
goto out;
}
if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) {
u64 mode = (*(u64 *)valp) & PSR_AA32_MODE_MASK;
switch (mode) {
case PSR_AA32_MODE_USR:
if (!system_supports_32bit_el0())
return -EINVAL;
break;
case PSR_AA32_MODE_FIQ:
case PSR_AA32_MODE_IRQ:
case PSR_AA32_MODE_SVC:
case PSR_AA32_MODE_ABT:
case PSR_AA32_MODE_UND:
if (!vcpu_el1_is_32bit(vcpu))
return -EINVAL;
break;
case PSR_MODE_EL0t:
case PSR_MODE_EL1t:
case PSR_MODE_EL1h:
if (vcpu_el1_is_32bit(vcpu))
return -EINVAL;
break;
default:
err = -EINVAL;
goto out;
}
}
memcpy((u32 *)regs + off, valp, KVM_REG_SIZE(reg->id));
out:
return err;
}
#define vq_word(vq) (((vq) - SVE_VQ_MIN) / 64)
#define vq_mask(vq) ((u64)1 << ((vq) - SVE_VQ_MIN) % 64)
#define vq_present(vqs, vq) (!!((vqs)[vq_word(vq)] & vq_mask(vq)))
static int get_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
unsigned int max_vq, vq;
u64 vqs[KVM_ARM64_SVE_VLS_WORDS];
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if (!vcpu_has_sve(vcpu))
return -ENOENT;
if (WARN_ON(!sve_vl_valid(vcpu->arch.sve_max_vl)))
return -EINVAL;
memset(vqs, 0, sizeof(vqs));
max_vq = sve_vq_from_vl(vcpu->arch.sve_max_vl);
for (vq = SVE_VQ_MIN; vq <= max_vq; ++vq)
if (sve_vq_available(vq))
vqs[vq_word(vq)] |= vq_mask(vq);
if (copy_to_user((void __user *)reg->addr, vqs, sizeof(vqs)))
return -EFAULT;
return 0;
}
static int set_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
unsigned int max_vq, vq;
u64 vqs[KVM_ARM64_SVE_VLS_WORDS];
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if (!vcpu_has_sve(vcpu))
return -ENOENT;
if (kvm_arm_vcpu_sve_finalized(vcpu))
return -EPERM; /* too late! */
if (WARN_ON(vcpu->arch.sve_state))
return -EINVAL;
if (copy_from_user(vqs, (const void __user *)reg->addr, sizeof(vqs)))
return -EFAULT;
max_vq = 0;
for (vq = SVE_VQ_MIN; vq <= SVE_VQ_MAX; ++vq)
if (vq_present(vqs, vq))
max_vq = vq;
if (max_vq > sve_vq_from_vl(kvm_sve_max_vl))
return -EINVAL;
/*
* Vector lengths supported by the host can't currently be
* hidden from the guest individually: instead we can only set a
* maxmium via ZCR_EL2.LEN. So, make sure the available vector
* lengths match the set requested exactly up to the requested
* maximum:
*/
for (vq = SVE_VQ_MIN; vq <= max_vq; ++vq)
if (vq_present(vqs, vq) != sve_vq_available(vq))
return -EINVAL;
/* Can't run with no vector lengths at all: */
if (max_vq < SVE_VQ_MIN)
return -EINVAL;
/* vcpu->arch.sve_state will be alloc'd by kvm_vcpu_finalize_sve() */
vcpu->arch.sve_max_vl = sve_vl_from_vq(max_vq);
return 0;
}
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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#define SVE_REG_SLICE_SHIFT 0
#define SVE_REG_SLICE_BITS 5
#define SVE_REG_ID_SHIFT (SVE_REG_SLICE_SHIFT + SVE_REG_SLICE_BITS)
#define SVE_REG_ID_BITS 5
#define SVE_REG_SLICE_MASK \
GENMASK(SVE_REG_SLICE_SHIFT + SVE_REG_SLICE_BITS - 1, \
SVE_REG_SLICE_SHIFT)
#define SVE_REG_ID_MASK \
GENMASK(SVE_REG_ID_SHIFT + SVE_REG_ID_BITS - 1, SVE_REG_ID_SHIFT)
#define SVE_NUM_SLICES (1 << SVE_REG_SLICE_BITS)
#define KVM_SVE_ZREG_SIZE KVM_REG_SIZE(KVM_REG_ARM64_SVE_ZREG(0, 0))
#define KVM_SVE_PREG_SIZE KVM_REG_SIZE(KVM_REG_ARM64_SVE_PREG(0, 0))
/*
* Number of register slices required to cover each whole SVE register.
* NOTE: Only the first slice every exists, for now.
* If you are tempted to modify this, you must also rework sve_reg_to_region()
* to match:
*/
#define vcpu_sve_slices(vcpu) 1
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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/* Bounds of a single SVE register slice within vcpu->arch.sve_state */
struct sve_state_reg_region {
unsigned int koffset; /* offset into sve_state in kernel memory */
unsigned int klen; /* length in kernel memory */
unsigned int upad; /* extra trailing padding in user memory */
};
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/*
* Validate SVE register ID and get sanitised bounds for user/kernel SVE
* register copy
*/
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
static int sve_reg_to_region(struct sve_state_reg_region *region,
struct kvm_vcpu *vcpu,
const struct kvm_one_reg *reg)
{
/* reg ID ranges for Z- registers */
const u64 zreg_id_min = KVM_REG_ARM64_SVE_ZREG(0, 0);
const u64 zreg_id_max = KVM_REG_ARM64_SVE_ZREG(SVE_NUM_ZREGS - 1,
SVE_NUM_SLICES - 1);
/* reg ID ranges for P- registers and FFR (which are contiguous) */
const u64 preg_id_min = KVM_REG_ARM64_SVE_PREG(0, 0);
const u64 preg_id_max = KVM_REG_ARM64_SVE_FFR(SVE_NUM_SLICES - 1);
unsigned int vq;
unsigned int reg_num;
unsigned int reqoffset, reqlen; /* User-requested offset and length */
unsigned int maxlen; /* Maxmimum permitted length */
size_t sve_state_size;
2019-04-06 00:17:08 +08:00
const u64 last_preg_id = KVM_REG_ARM64_SVE_PREG(SVE_NUM_PREGS - 1,
SVE_NUM_SLICES - 1);
/* Verify that the P-regs and FFR really do have contiguous IDs: */
BUILD_BUG_ON(KVM_REG_ARM64_SVE_FFR(0) != last_preg_id + 1);
/* Verify that we match the UAPI header: */
BUILD_BUG_ON(SVE_NUM_SLICES != KVM_ARM64_SVE_MAX_SLICES);
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
reg_num = (reg->id & SVE_REG_ID_MASK) >> SVE_REG_ID_SHIFT;
if (reg->id >= zreg_id_min && reg->id <= zreg_id_max) {
2019-04-11 23:13:39 +08:00
if (!vcpu_has_sve(vcpu) || (reg->id & SVE_REG_SLICE_MASK) > 0)
return -ENOENT;
vq = sve_vq_from_vl(vcpu->arch.sve_max_vl);
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
reqoffset = SVE_SIG_ZREG_OFFSET(vq, reg_num) -
SVE_SIG_REGS_OFFSET;
reqlen = KVM_SVE_ZREG_SIZE;
maxlen = SVE_SIG_ZREG_SIZE(vq);
} else if (reg->id >= preg_id_min && reg->id <= preg_id_max) {
2019-04-11 23:13:39 +08:00
if (!vcpu_has_sve(vcpu) || (reg->id & SVE_REG_SLICE_MASK) > 0)
return -ENOENT;
vq = sve_vq_from_vl(vcpu->arch.sve_max_vl);
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
reqoffset = SVE_SIG_PREG_OFFSET(vq, reg_num) -
SVE_SIG_REGS_OFFSET;
reqlen = KVM_SVE_PREG_SIZE;
maxlen = SVE_SIG_PREG_SIZE(vq);
} else {
2019-04-11 23:13:39 +08:00
return -EINVAL;
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
}
sve_state_size = vcpu_sve_state_size(vcpu);
if (WARN_ON(!sve_state_size))
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
return -EINVAL;
region->koffset = array_index_nospec(reqoffset, sve_state_size);
region->klen = min(maxlen, reqlen);
region->upad = reqlen - region->klen;
return 0;
}
static int get_sve_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
2019-04-11 23:13:39 +08:00
int ret;
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
struct sve_state_reg_region region;
char __user *uptr = (char __user *)reg->addr;
/* Handle the KVM_REG_ARM64_SVE_VLS pseudo-reg as a special case: */
if (reg->id == KVM_REG_ARM64_SVE_VLS)
return get_sve_vls(vcpu, reg);
2019-04-11 23:13:39 +08:00
/* Try to interpret reg ID as an architectural SVE register... */
ret = sve_reg_to_region(&region, vcpu, reg);
if (ret)
return ret;
if (!kvm_arm_vcpu_sve_finalized(vcpu))
return -EPERM;
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
if (copy_to_user(uptr, vcpu->arch.sve_state + region.koffset,
region.klen) ||
clear_user(uptr + region.klen, region.upad))
return -EFAULT;
return 0;
}
static int set_sve_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
2019-04-11 23:13:39 +08:00
int ret;
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
struct sve_state_reg_region region;
const char __user *uptr = (const char __user *)reg->addr;
/* Handle the KVM_REG_ARM64_SVE_VLS pseudo-reg as a special case: */
if (reg->id == KVM_REG_ARM64_SVE_VLS)
return set_sve_vls(vcpu, reg);
2019-04-11 23:13:39 +08:00
/* Try to interpret reg ID as an architectural SVE register... */
ret = sve_reg_to_region(&region, vcpu, reg);
if (ret)
return ret;
if (!kvm_arm_vcpu_sve_finalized(vcpu))
return -EPERM;
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
if (copy_from_user(vcpu->arch.sve_state + region.koffset, uptr,
region.klen))
return -EFAULT;
return 0;
}
int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
return -EINVAL;
}
static int copy_core_reg_indices(const struct kvm_vcpu *vcpu,
u64 __user *uindices)
{
unsigned int i;
int n = 0;
for (i = 0; i < sizeof(struct kvm_regs) / sizeof(__u32); i++) {
KVM: arm64: Filter out invalid core register IDs in KVM_GET_REG_LIST Since commit d26c25a9d19b ("arm64: KVM: Tighten guest core register access from userspace"), KVM_{GET,SET}_ONE_REG rejects register IDs that do not correspond to a single underlying architectural register. KVM_GET_REG_LIST was not changed to match however: instead, it simply yields a list of 32-bit register IDs that together cover the whole kvm_regs struct. This means that if userspace tries to use the resulting list of IDs directly to drive calls to KVM_*_ONE_REG, some of those calls will now fail. This was not the intention. Instead, iterating KVM_*_ONE_REG over the list of IDs returned by KVM_GET_REG_LIST should be guaranteed to work. This patch fixes the problem by splitting validate_core_offset() into a backend core_reg_size_from_offset() which does all of the work except for checking that the size field in the register ID matches, and kvm_arm_copy_reg_indices() and num_core_regs() are converted to use this to enumerate the valid offsets. kvm_arm_copy_reg_indices() now also sets the register ID size field appropriately based on the value returned, so the register ID supplied to userspace is fully qualified for use with the register access ioctls. Cc: stable@vger.kernel.org Fixes: d26c25a9d19b ("arm64: KVM: Tighten guest core register access from userspace") Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Tested-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-06-12 20:44:49 +08:00
u64 reg = KVM_REG_ARM64 | KVM_REG_ARM_CORE | i;
int size = core_reg_size_from_offset(vcpu, i);
if (size < 0)
continue;
switch (size) {
case sizeof(__u32):
reg |= KVM_REG_SIZE_U32;
break;
case sizeof(__u64):
reg |= KVM_REG_SIZE_U64;
break;
case sizeof(__uint128_t):
reg |= KVM_REG_SIZE_U128;
break;
default:
WARN_ON(1);
continue;
KVM: arm64: Filter out invalid core register IDs in KVM_GET_REG_LIST Since commit d26c25a9d19b ("arm64: KVM: Tighten guest core register access from userspace"), KVM_{GET,SET}_ONE_REG rejects register IDs that do not correspond to a single underlying architectural register. KVM_GET_REG_LIST was not changed to match however: instead, it simply yields a list of 32-bit register IDs that together cover the whole kvm_regs struct. This means that if userspace tries to use the resulting list of IDs directly to drive calls to KVM_*_ONE_REG, some of those calls will now fail. This was not the intention. Instead, iterating KVM_*_ONE_REG over the list of IDs returned by KVM_GET_REG_LIST should be guaranteed to work. This patch fixes the problem by splitting validate_core_offset() into a backend core_reg_size_from_offset() which does all of the work except for checking that the size field in the register ID matches, and kvm_arm_copy_reg_indices() and num_core_regs() are converted to use this to enumerate the valid offsets. kvm_arm_copy_reg_indices() now also sets the register ID size field appropriately based on the value returned, so the register ID supplied to userspace is fully qualified for use with the register access ioctls. Cc: stable@vger.kernel.org Fixes: d26c25a9d19b ("arm64: KVM: Tighten guest core register access from userspace") Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Tested-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-06-12 20:44:49 +08:00
}
if (uindices) {
KVM: arm64: Filter out invalid core register IDs in KVM_GET_REG_LIST Since commit d26c25a9d19b ("arm64: KVM: Tighten guest core register access from userspace"), KVM_{GET,SET}_ONE_REG rejects register IDs that do not correspond to a single underlying architectural register. KVM_GET_REG_LIST was not changed to match however: instead, it simply yields a list of 32-bit register IDs that together cover the whole kvm_regs struct. This means that if userspace tries to use the resulting list of IDs directly to drive calls to KVM_*_ONE_REG, some of those calls will now fail. This was not the intention. Instead, iterating KVM_*_ONE_REG over the list of IDs returned by KVM_GET_REG_LIST should be guaranteed to work. This patch fixes the problem by splitting validate_core_offset() into a backend core_reg_size_from_offset() which does all of the work except for checking that the size field in the register ID matches, and kvm_arm_copy_reg_indices() and num_core_regs() are converted to use this to enumerate the valid offsets. kvm_arm_copy_reg_indices() now also sets the register ID size field appropriately based on the value returned, so the register ID supplied to userspace is fully qualified for use with the register access ioctls. Cc: stable@vger.kernel.org Fixes: d26c25a9d19b ("arm64: KVM: Tighten guest core register access from userspace") Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Tested-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-06-12 20:44:49 +08:00
if (put_user(reg, uindices))
return -EFAULT;
uindices++;
}
n++;
}
return n;
}
static unsigned long num_core_regs(const struct kvm_vcpu *vcpu)
{
return copy_core_reg_indices(vcpu, NULL);
}
/**
* ARM64 versions of the TIMER registers, always available on arm64
*/
#define NUM_TIMER_REGS 3
static bool is_timer_reg(u64 index)
{
switch (index) {
case KVM_REG_ARM_TIMER_CTL:
case KVM_REG_ARM_TIMER_CNT:
case KVM_REG_ARM_TIMER_CVAL:
return true;
}
return false;
}
static int copy_timer_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
{
if (put_user(KVM_REG_ARM_TIMER_CTL, uindices))
return -EFAULT;
uindices++;
if (put_user(KVM_REG_ARM_TIMER_CNT, uindices))
return -EFAULT;
uindices++;
if (put_user(KVM_REG_ARM_TIMER_CVAL, uindices))
return -EFAULT;
return 0;
}
static int set_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
void __user *uaddr = (void __user *)(long)reg->addr;
u64 val;
int ret;
ret = copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id));
if (ret != 0)
return -EFAULT;
return kvm_arm_timer_set_reg(vcpu, reg->id, val);
}
static int get_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
void __user *uaddr = (void __user *)(long)reg->addr;
u64 val;
val = kvm_arm_timer_get_reg(vcpu, reg->id);
return copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id)) ? -EFAULT : 0;
}
static unsigned long num_sve_regs(const struct kvm_vcpu *vcpu)
{
const unsigned int slices = vcpu_sve_slices(vcpu);
if (!vcpu_has_sve(vcpu))
return 0;
/* Policed by KVM_GET_REG_LIST: */
WARN_ON(!kvm_arm_vcpu_sve_finalized(vcpu));
return slices * (SVE_NUM_PREGS + SVE_NUM_ZREGS + 1 /* FFR */)
+ 1; /* KVM_REG_ARM64_SVE_VLS */
}
static int copy_sve_reg_indices(const struct kvm_vcpu *vcpu,
u64 __user *uindices)
{
const unsigned int slices = vcpu_sve_slices(vcpu);
u64 reg;
unsigned int i, n;
int num_regs = 0;
if (!vcpu_has_sve(vcpu))
return 0;
/* Policed by KVM_GET_REG_LIST: */
WARN_ON(!kvm_arm_vcpu_sve_finalized(vcpu));
/*
* Enumerate this first, so that userspace can save/restore in
* the order reported by KVM_GET_REG_LIST:
*/
reg = KVM_REG_ARM64_SVE_VLS;
if (put_user(reg, uindices++))
return -EFAULT;
++num_regs;
for (i = 0; i < slices; i++) {
for (n = 0; n < SVE_NUM_ZREGS; n++) {
reg = KVM_REG_ARM64_SVE_ZREG(n, i);
if (put_user(reg, uindices++))
return -EFAULT;
num_regs++;
}
for (n = 0; n < SVE_NUM_PREGS; n++) {
reg = KVM_REG_ARM64_SVE_PREG(n, i);
if (put_user(reg, uindices++))
return -EFAULT;
num_regs++;
}
reg = KVM_REG_ARM64_SVE_FFR(i);
if (put_user(reg, uindices++))
return -EFAULT;
num_regs++;
}
return num_regs;
}
/**
* kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG
*
* This is for all registers.
*/
unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
{
unsigned long res = 0;
res += num_core_regs(vcpu);
res += num_sve_regs(vcpu);
res += kvm_arm_num_sys_reg_descs(vcpu);
res += kvm_arm_get_fw_num_regs(vcpu);
res += NUM_TIMER_REGS;
return res;
}
/**
* kvm_arm_copy_reg_indices - get indices of all registers.
*
* We do core registers right here, then we append system regs.
*/
int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
{
int ret;
ret = copy_core_reg_indices(vcpu, uindices);
if (ret < 0)
return ret;
uindices += ret;
ret = copy_sve_reg_indices(vcpu, uindices);
if (ret < 0)
return ret;
uindices += ret;
ret = kvm_arm_copy_fw_reg_indices(vcpu, uindices);
if (ret < 0)
return ret;
uindices += kvm_arm_get_fw_num_regs(vcpu);
ret = copy_timer_indices(vcpu, uindices);
if (ret < 0)
return ret;
uindices += NUM_TIMER_REGS;
return kvm_arm_copy_sys_reg_indices(vcpu, uindices);
}
int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
/* We currently use nothing arch-specific in upper 32 bits */
if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
return -EINVAL;
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
switch (reg->id & KVM_REG_ARM_COPROC_MASK) {
case KVM_REG_ARM_CORE: return get_core_reg(vcpu, reg);
case KVM_REG_ARM_FW: return kvm_arm_get_fw_reg(vcpu, reg);
case KVM_REG_ARM64_SVE: return get_sve_reg(vcpu, reg);
}
if (is_timer_reg(reg->id))
return get_timer_reg(vcpu, reg);
return kvm_arm_sys_reg_get_reg(vcpu, reg);
}
int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
/* We currently use nothing arch-specific in upper 32 bits */
if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
return -EINVAL;
KVM: arm64/sve: Add SVE support to register access ioctl interface This patch adds the following registers for access via the KVM_{GET,SET}_ONE_REG interface: * KVM_REG_ARM64_SVE_ZREG(n, i) (n = 0..31) (in 2048-bit slices) * KVM_REG_ARM64_SVE_PREG(n, i) (n = 0..15) (in 256-bit slices) * KVM_REG_ARM64_SVE_FFR(i) (in 256-bit slices) In order to adapt gracefully to future architectural extensions, the registers are logically divided up into slices as noted above: the i parameter denotes the slice index. This allows us to reserve space in the ABI for future expansion of these registers. However, as of today the architecture does not permit registers to be larger than a single slice, so no code is needed in the kernel to expose additional slices, for now. The code can be extended later as needed to expose them up to a maximum of 32 slices (as carved out in the architecture itself) if they really exist someday. The registers are only visible for vcpus that have SVE enabled. They are not enumerated by KVM_GET_REG_LIST on vcpus that do not have SVE. Accesses to the FPSIMD registers via KVM_REG_ARM_CORE is not allowed for SVE-enabled vcpus: SVE-aware userspace can use the KVM_REG_ARM64_SVE_ZREG() interface instead to access the same register state. This avoids some complex and pointless emulation in the kernel to convert between the two views of these aliased registers. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-28 21:39:19 +08:00
switch (reg->id & KVM_REG_ARM_COPROC_MASK) {
case KVM_REG_ARM_CORE: return set_core_reg(vcpu, reg);
case KVM_REG_ARM_FW: return kvm_arm_set_fw_reg(vcpu, reg);
case KVM_REG_ARM64_SVE: return set_sve_reg(vcpu, reg);
}
if (is_timer_reg(reg->id))
return set_timer_reg(vcpu, reg);
return kvm_arm_sys_reg_set_reg(vcpu, reg);
}
int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
struct kvm_sregs *sregs)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
struct kvm_sregs *sregs)
{
return -EINVAL;
}
int __kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
struct kvm_vcpu_events *events)
{
events->exception.serror_pending = !!(vcpu->arch.hcr_el2 & HCR_VSE);
events->exception.serror_has_esr = cpus_have_const_cap(ARM64_HAS_RAS_EXTN);
if (events->exception.serror_pending && events->exception.serror_has_esr)
events->exception.serror_esr = vcpu_get_vsesr(vcpu);
return 0;
}
int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
struct kvm_vcpu_events *events)
{
bool serror_pending = events->exception.serror_pending;
bool has_esr = events->exception.serror_has_esr;
if (serror_pending && has_esr) {
if (!cpus_have_const_cap(ARM64_HAS_RAS_EXTN))
return -EINVAL;
if (!((events->exception.serror_esr) & ~ESR_ELx_ISS_MASK))
kvm_set_sei_esr(vcpu, events->exception.serror_esr);
else
return -EINVAL;
} else if (serror_pending) {
kvm_inject_vabt(vcpu);
}
return 0;
}
int __attribute_const__ kvm_target_cpu(void)
{
unsigned long implementor = read_cpuid_implementor();
unsigned long part_number = read_cpuid_part_number();
switch (implementor) {
case ARM_CPU_IMP_ARM:
switch (part_number) {
case ARM_CPU_PART_AEM_V8:
return KVM_ARM_TARGET_AEM_V8;
case ARM_CPU_PART_FOUNDATION:
return KVM_ARM_TARGET_FOUNDATION_V8;
case ARM_CPU_PART_CORTEX_A53:
return KVM_ARM_TARGET_CORTEX_A53;
case ARM_CPU_PART_CORTEX_A57:
return KVM_ARM_TARGET_CORTEX_A57;
}
break;
case ARM_CPU_IMP_APM:
switch (part_number) {
case APM_CPU_PART_POTENZA:
return KVM_ARM_TARGET_XGENE_POTENZA;
}
break;
}
/* Return a default generic target */
return KVM_ARM_TARGET_GENERIC_V8;
}
int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init)
{
int target = kvm_target_cpu();
if (target < 0)
return -ENODEV;
memset(init, 0, sizeof(*init));
/*
* For now, we don't return any features.
* In future, we might use features to return target
* specific features available for the preferred
* target type.
*/
init->target = (__u32)target;
return 0;
}
int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
struct kvm_translation *tr)
{
return -EINVAL;
}
#define KVM_GUESTDBG_VALID_MASK (KVM_GUESTDBG_ENABLE | \
KVM_GUESTDBG_USE_SW_BP | \
KVM_GUESTDBG_USE_HW | \
KVM_GUESTDBG_SINGLESTEP)
/**
* kvm_arch_vcpu_ioctl_set_guest_debug - set up guest debugging
* @kvm: pointer to the KVM struct
* @kvm_guest_debug: the ioctl data buffer
*
* This sets up and enables the VM for guest debugging. Userspace
* passes in a control flag to enable different debug types and
* potentially other architecture specific information in the rest of
* the structure.
*/
int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
struct kvm_guest_debug *dbg)
{
int ret = 0;
trace_kvm_set_guest_debug(vcpu, dbg->control);
if (dbg->control & ~KVM_GUESTDBG_VALID_MASK) {
ret = -EINVAL;
goto out;
}
if (dbg->control & KVM_GUESTDBG_ENABLE) {
vcpu->guest_debug = dbg->control;
/* Hardware assisted Break and Watch points */
if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) {
vcpu->arch.external_debug_state = dbg->arch;
}
} else {
/* If not enabled clear all flags */
vcpu->guest_debug = 0;
}
out:
return ret;
}
int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr)
{
int ret;
switch (attr->group) {
case KVM_ARM_VCPU_PMU_V3_CTRL:
ret = kvm_arm_pmu_v3_set_attr(vcpu, attr);
break;
case KVM_ARM_VCPU_TIMER_CTRL:
ret = kvm_arm_timer_set_attr(vcpu, attr);
break;
default:
ret = -ENXIO;
break;
}
return ret;
}
int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr)
{
int ret;
switch (attr->group) {
case KVM_ARM_VCPU_PMU_V3_CTRL:
ret = kvm_arm_pmu_v3_get_attr(vcpu, attr);
break;
case KVM_ARM_VCPU_TIMER_CTRL:
ret = kvm_arm_timer_get_attr(vcpu, attr);
break;
default:
ret = -ENXIO;
break;
}
return ret;
}
int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr)
{
int ret;
switch (attr->group) {
case KVM_ARM_VCPU_PMU_V3_CTRL:
ret = kvm_arm_pmu_v3_has_attr(vcpu, attr);
break;
case KVM_ARM_VCPU_TIMER_CTRL:
ret = kvm_arm_timer_has_attr(vcpu, attr);
break;
default:
ret = -ENXIO;
break;
}
return ret;
}