From: Will Deacon will@kernel.org

mainline inclusion from mainline-v5.13-rc1 commit 923961a7ff2e94d3d824d9ea7047178a5a123245 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I8DWT1 CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...

--------------------------------

We can advertise ourselves to guests as KVM and provide a basic features bitmap for discoverability of future hypervisor services.

Cc: Marc Zyngier maz@kernel.org Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Jianyong Wu jianyong.wu@arm.com Signed-off-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20201209060932.212364-3-jianyong.wu@arm.com Signed-off-by: Kunkun Jiang jiangkunkun@huawei.com Signed-off-by: Dongxu Sun sundongxu3@huawei.com --- arch/arm64/kvm/hypercalls.c | 41 ++++++++++++++++++++++--------------- 1 file changed, 25 insertions(+), 16 deletions(-)

diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c index 3ed08077fe15..c9faa4c954c8 100644 --- a/arch/arm64/kvm/hypercalls.c +++ b/arch/arm64/kvm/hypercalls.c @@ -12,13 +12,13 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) { u32 func_id = smccc_get_function(vcpu); - long val = SMCCC_RET_NOT_SUPPORTED; + u64 val[4] = {SMCCC_RET_NOT_SUPPORTED}; u32 feature; gpa_t gpa;

switch (func_id) { case ARM_SMCCC_VERSION_FUNC_ID: - val = ARM_SMCCC_VERSION_1_1; + val[0] = ARM_SMCCC_VERSION_1_1; break; case ARM_SMCCC_ARCH_FEATURES_FUNC_ID: feature = smccc_get_arg1(vcpu); @@ -28,10 +28,10 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) case SPECTRE_VULNERABLE: break; case SPECTRE_MITIGATED: - val = SMCCC_RET_SUCCESS; + val[0] = SMCCC_RET_SUCCESS; break; case SPECTRE_UNAFFECTED: - val = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED; + val[0] = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED; break; } break; @@ -54,7 +54,7 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) break; fallthrough; case SPECTRE_UNAFFECTED: - val = SMCCC_RET_NOT_REQUIRED; + val[0] = SMCCC_RET_NOT_REQUIRED; break; } break; @@ -63,45 +63,54 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) case SPECTRE_VULNERABLE: break; case SPECTRE_MITIGATED: - val = SMCCC_RET_SUCCESS; + val[0] = SMCCC_RET_SUCCESS; break; case SPECTRE_UNAFFECTED: - val = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED; + val[0] = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED; break; } break; case ARM_SMCCC_HV_PV_TIME_FEATURES: - val = SMCCC_RET_SUCCESS; + val[0] = SMCCC_RET_SUCCESS; break; case ARM_SMCCC_HV_PV_SCHED_FEATURES: - val = SMCCC_RET_SUCCESS; + val[0] = SMCCC_RET_SUCCESS; break; } break; case ARM_SMCCC_HV_PV_TIME_FEATURES: - val = kvm_hypercall_pv_features(vcpu); + val[0] = kvm_hypercall_pv_features(vcpu); break; case ARM_SMCCC_HV_PV_TIME_ST: gpa = kvm_init_stolen_time(vcpu); if (gpa != GPA_INVALID) - val = gpa; + val[0] = gpa; + break; + case ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID: + val[0] = ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_0; + val[1] = ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_1; + val[2] = ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_2; + val[3] = ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_3; + break; + case ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID: + val[0] = BIT(ARM_SMCCC_KVM_FUNC_FEATURES); break; case ARM_SMCCC_HV_PV_SCHED_FEATURES: - val = kvm_hypercall_pvsched_features(vcpu); + val[0] = kvm_hypercall_pvsched_features(vcpu); break; case ARM_SMCCC_HV_PV_SCHED_IPA_INIT: gpa = smccc_get_arg1(vcpu); if (gpa != GPA_INVALID) { vcpu->arch.pvsched.base = gpa; - val = SMCCC_RET_SUCCESS; + val[0] = SMCCC_RET_SUCCESS; } break; case ARM_SMCCC_HV_PV_SCHED_IPA_RELEASE: vcpu->arch.pvsched.base = GPA_INVALID; - val = SMCCC_RET_SUCCESS; + val[0] = SMCCC_RET_SUCCESS; break; case ARM_SMCCC_HV_PV_SCHED_KICK_CPU: - val = kvm_pvsched_kick_vcpu(vcpu); + val[0] = kvm_pvsched_kick_vcpu(vcpu); break; case ARM_SMCCC_TRNG_VERSION: case ARM_SMCCC_TRNG_FEATURES: @@ -113,6 +122,6 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) return kvm_psci_call(vcpu); }

- smccc_set_retval(vcpu, val, 0, 0, 0); + smccc_set_retval(vcpu, val[0], val[1], val[2], val[3]); return 1; }

From: Thomas Gleixner tglx@linutronix.de

mainline inclusion from mainline-v5.13-rc1 commit b2c67cbe9f447312f5cdd7c6641b463f2349aec0 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I8DWT1 CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...

--------------------------------

System time snapshots are not conveying information about the current clocksource which was used, but callers like the PTP KVM guest implementation have the requirement to evaluate the clocksource type to select the appropriate mechanism.

Introduce a clocksource id field in struct clocksource which is by default set to CSID_GENERIC (0). Clocksource implementations can set that field to a value which allows to identify the clocksource.

Store the clocksource id of the current clocksource in the system_time_snapshot so callers can evaluate which clocksource was used to take the snapshot and act accordingly.

Signed-off-by: Thomas Gleixner tglx@linutronix.de Signed-off-by: Jianyong Wu jianyong.wu@arm.com Signed-off-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20201209060932.212364-5-jianyong.wu@arm.com Signed-off-by: Kunkun Jiang jiangkunkun@huawei.com Signed-off-by: Dongxu Sun sundongxu3@huawei.com --- include/linux/clocksource.h | 6 ++++++ include/linux/clocksource_ids.h | 11 +++++++++++ include/linux/timekeeping.h | 12 +++++++----- kernel/time/clocksource.c | 2 ++ kernel/time/timekeeping.c | 1 + 5 files changed, 27 insertions(+), 5 deletions(-) create mode 100644 include/linux/clocksource_ids.h

diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 4c3ecccc44ed..c68c28de91e4 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -17,6 +17,7 @@ #include <linux/timer.h> #include <linux/init.h> #include <linux/of.h> +#include <linux/clocksource_ids.h> #include <asm/div64.h> #include <asm/io.h>

@@ -62,6 +63,10 @@ struct module; * 400-499: Perfect * The ideal clocksource. A must-use where * available. + * @id: Defaults to CSID_GENERIC. The id value is captured + * in certain snapshot functions to allow callers to + * validate the clocksource from which the snapshot was + * taken. * @flags: Flags describing special properties * @enable: Optional function to enable the clocksource * @disable: Optional function to disable the clocksource @@ -100,6 +105,7 @@ struct clocksource { const char *name; struct list_head list; int rating; + enum clocksource_ids id; enum vdso_clock_mode vdso_clock_mode; u16 vdso_fix; u16 vdso_shift; diff --git a/include/linux/clocksource_ids.h b/include/linux/clocksource_ids.h new file mode 100644 index 000000000000..4d8e19e05328 --- /dev/null +++ b/include/linux/clocksource_ids.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_CLOCKSOURCE_IDS_H +#define _LINUX_CLOCKSOURCE_IDS_H + +/* Enum to give clocksources a unique identifier */ +enum clocksource_ids { + CSID_GENERIC = 0, + CSID_MAX, +}; + +#endif diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 7f7e4a3f4394..2ee05355333f 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -3,6 +3,7 @@ #define _LINUX_TIMEKEEPING_H

#include <linux/errno.h> +#include <linux/clocksource_ids.h>

/* Included from linux/ktime.h */

@@ -244,11 +245,12 @@ struct ktime_timestamps { * @cs_was_changed_seq: The sequence number of clocksource change events */ struct system_time_snapshot { - u64 cycles; - ktime_t real; - ktime_t raw; - unsigned int clock_was_set_seq; - u8 cs_was_changed_seq; + u64 cycles; + ktime_t real; + ktime_t raw; + enum clocksource_ids cs_id; + unsigned int clock_was_set_seq; + u8 cs_was_changed_seq; };

/** diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 74492f08660c..1657b5e74c64 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -1029,6 +1029,8 @@ int __clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq)

clocksource_arch_init(cs);

+ if (WARN_ON_ONCE((unsigned int)cs->id >= CSID_MAX)) + cs->id = CSID_GENERIC; if (cs->vdso_clock_mode < 0 || cs->vdso_clock_mode >= VDSO_CLOCKMODE_MAX) { pr_warn("clocksource %s registered with invalid VDSO mode %d. Disabling VDSO support.\n", diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index c8d9b89a7571..85fb84e545fa 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1065,6 +1065,7 @@ void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot) do { seq = read_seqcount_begin(&tk_core.seq); now = tk_clock_read(&tk->tkr_mono); + systime_snapshot->cs_id = tk->tkr_mono.clock->id; systime_snapshot->cs_was_changed_seq = tk->cs_was_changed_seq; systime_snapshot->clock_was_set_seq = tk->clock_was_set_seq; base_real = ktime_add(tk->tkr_mono.base,

From: Jianyong Wu jianyong.wu@arm.com

mainline inclusion from mainline-v5.13-rc1 commit 3bf725699bf62494b3e179f1795f08c7d749f061 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I8DWT1 CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...

--------------------------------

Implement the hypervisor side of the KVM PTP interface.

The service offers wall time and cycle count from host to guest. The caller must specify whether they want the host's view of either the virtual or physical counter.

Signed-off-by: Jianyong Wu jianyong.wu@arm.com Signed-off-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20201209060932.212364-7-jianyong.wu@arm.com Signed-off-by: Kunkun Jiang jiangkunkun@huawei.com Signed-off-by: Dongxu Sun sundongxu3@huawei.com --- Documentation/virt/kvm/api.rst | 9 +++++ Documentation/virt/kvm/arm/index.rst | 1 + Documentation/virt/kvm/arm/ptp_kvm.rst | 25 ++++++++++++ arch/arm64/kvm/arm.c | 1 + arch/arm64/kvm/hypercalls.c | 53 ++++++++++++++++++++++++++ include/linux/arm-smccc.h | 16 ++++++++ include/uapi/linux/kvm.h | 1 + 7 files changed, 106 insertions(+) create mode 100644 Documentation/virt/kvm/arm/ptp_kvm.rst

diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index f1fb66bff1c0..7eb16d71d7e2 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -6822,3 +6822,12 @@ Ordering of KVM_GET_*/KVM_SET_* ioctls ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

TBD + +8.31 KVM_CAP_PTP_KVM +-------------------- + +:Architectures: arm64 + +This capability indicates that the KVM virtual PTP service is +supported in the host. A VMM can check whether the service is +available to the guest on migration. diff --git a/Documentation/virt/kvm/arm/index.rst b/Documentation/virt/kvm/arm/index.rst index 3e2b2aba90fc..78a9b670aafe 100644 --- a/Documentation/virt/kvm/arm/index.rst +++ b/Documentation/virt/kvm/arm/index.rst @@ -10,3 +10,4 @@ ARM hyp-abi psci pvtime + ptp_kvm diff --git a/Documentation/virt/kvm/arm/ptp_kvm.rst b/Documentation/virt/kvm/arm/ptp_kvm.rst new file mode 100644 index 000000000000..68cffb50d8bf --- /dev/null +++ b/Documentation/virt/kvm/arm/ptp_kvm.rst @@ -0,0 +1,25 @@ +.. SPDX-License-Identifier: GPL-2.0 + +PTP_KVM support for arm/arm64 +============================= + +PTP_KVM is used for high precision time sync between host and guests. +It relies on transferring the wall clock and counter value from the +host to the guest using a KVM-specific hypercall. + +* ARM_SMCCC_HYP_KVM_PTP_FUNC_ID: 0x86000001 + +This hypercall uses the SMC32/HVC32 calling convention: + +ARM_SMCCC_HYP_KVM_PTP_FUNC_ID + ============= ========== ========== + Function ID: (uint32) 0x86000001 + Arguments: (uint32) KVM_PTP_VIRT_COUNTER(0) + KVM_PTP_PHYS_COUNTER(1) + Return Values: (int32) NOT_SUPPORTED(-1) on error, or + (uint32) Upper 32 bits of wall clock time (r0) + (uint32) Lower 32 bits of wall clock time (r1) + (uint32) Upper 32 bits of counter (r2) + (uint32) Lower 32 bits of counter (r3) + Endianness: No Restrictions. + ============= ========== ========== diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index bc5a91d17a71..7dbfeae689dd 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -228,6 +228,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_ARM_NISV_TO_USER: case KVM_CAP_ARM_INJECT_EXT_DABT: case KVM_CAP_ARM_CPU_FEATURE: + case KVM_CAP_PTP_KVM: r = 1; break; case KVM_CAP_ARM_SET_DEVICE_ADDR: diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c index c9faa4c954c8..58a4a8c0ca4a 100644 --- a/arch/arm64/kvm/hypercalls.c +++ b/arch/arm64/kvm/hypercalls.c @@ -9,6 +9,55 @@ #include <kvm/arm_hypercalls.h> #include <kvm/arm_psci.h>

+static void kvm_ptp_get_time(struct kvm_vcpu *vcpu, u64 *val) +{ + struct system_time_snapshot systime_snapshot; + u64 cycles = ~0UL; + u32 feature; + + /* + * system time and counter value must captured at the same + * time to keep consistency and precision. + */ + ktime_get_snapshot(&systime_snapshot); + + /* + * This is only valid if the current clocksource is the + * architected counter, as this is the only one the guest + * can see. + */ + if (systime_snapshot.cs_id != CSID_ARM_ARCH_COUNTER) + return; + + /* + * The guest selects one of the two reference counters + * (virtual or physical) with the first argument of the SMCCC + * call. In case the identifier is not supported, error out. + */ + feature = smccc_get_arg1(vcpu); + switch (feature) { + case KVM_PTP_VIRT_COUNTER: + cycles = systime_snapshot.cycles - vcpu_read_sys_reg(vcpu, CNTVOFF_EL2); + break; + case KVM_PTP_PHYS_COUNTER: + cycles = systime_snapshot.cycles; + break; + default: + return; + } + + /* + * This relies on the top bit of val[0] never being set for + * valid values of system time, because that is *really* far + * in the future (about 292 years from 1970, and at that stage + * nobody will give a damn about it). + */ + val[0] = upper_32_bits(systime_snapshot.real); + val[1] = lower_32_bits(systime_snapshot.real); + val[2] = upper_32_bits(cycles); + val[3] = lower_32_bits(cycles); +} + int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) { u32 func_id = smccc_get_function(vcpu); @@ -94,6 +143,10 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) break; case ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID: val[0] = BIT(ARM_SMCCC_KVM_FUNC_FEATURES); + val[0] |= BIT(ARM_SMCCC_KVM_FUNC_PTP); + break; + case ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID: + kvm_ptp_get_time(vcpu, val); break; case ARM_SMCCC_HV_PV_SCHED_FEATURES: val[0] = kvm_hypercall_pvsched_features(vcpu); diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h index 4ff0189c071f..9e50a386ec8f 100644 --- a/include/linux/arm-smccc.h +++ b/include/linux/arm-smccc.h @@ -111,6 +111,7 @@

/* KVM "vendor specific" services */ #define ARM_SMCCC_KVM_FUNC_FEATURES 0 +#define ARM_SMCCC_KVM_FUNC_PTP 1 #define ARM_SMCCC_KVM_FUNC_FEATURES_2 127 #define ARM_SMCCC_KVM_NUM_FUNCS 128

@@ -122,6 +123,21 @@

#define SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED 1

+/* + * ptp_kvm is a feature used for time sync between vm and host. + * ptp_kvm module in guest kernel will get service from host using + * this hypercall ID. + */ +#define ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_VENDOR_HYP, \ + ARM_SMCCC_KVM_FUNC_PTP) + +/* ptp_kvm counter type ID */ +#define KVM_PTP_VIRT_COUNTER 0 +#define KVM_PTP_PHYS_COUNTER 1 + /* Paravirtualised time calls (defined by ARM DEN0057A) */ #define ARM_SMCCC_HV_PV_TIME_FEATURES \ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 90b2e4a3198d..f8893349a278 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -1087,6 +1087,7 @@ struct kvm_ppc_resize_hpt { #define KVM_CAP_X86_MSR_FILTER 189 #define KVM_CAP_ENFORCE_PV_FEATURE_CPUID 190 #define KVM_CAP_X86_BUS_LOCK_EXIT 193 +#define KVM_CAP_PTP_KVM 195 #define KVM_CAP_SGX_ATTRIBUTE 196 #define KVM_CAP_XSAVE2 208 #define KVM_CAP_SYS_ATTRIBUTES 209

From: Jianyong Wu jianyong.wu@arm.com

mainline inclusion from mainline-v5.13-rc1 commit 300bb1fe767183a1ca1dadf691409c53c4ecff4b category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I8DWT1 CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...

--------------------------------

Currently, there is no mechanism to keep time sync between guest and host in arm/arm64 virtualization environment. Time in guest will drift compared with host after boot up as they may both use third party time sources to correct their time respectively. The time deviation will be in order of milliseconds. But in some scenarios,like in cloud environment, we ask for higher time precision.

kvm ptp clock, which chooses the host clock source as a reference clock to sync time between guest and host, has been adopted by x86 which takes the time sync order from milliseconds to nanoseconds.

This patch enables kvm ptp clock for arm/arm64 and improves clock sync precision significantly.

Test result comparisons between with kvm ptp clock and without it in arm/arm64 are as follows. This test derived from the result of command 'chronyc sources'. we should take more care of the last sample column which shows the offset between the local clock and the source at the last measurement.

no kvm ptp in guest: MS Name/IP address Stratum Poll Reach LastRx Last sample ======================================================================== ^* dns1.synet.edu.cn 2 6 377 13 +1040us[+1581us] +/- 21ms ^* dns1.synet.edu.cn 2 6 377 21 +1040us[+1581us] +/- 21ms ^* dns1.synet.edu.cn 2 6 377 29 +1040us[+1581us] +/- 21ms ^* dns1.synet.edu.cn 2 6 377 37 +1040us[+1581us] +/- 21ms ^* dns1.synet.edu.cn 2 6 377 45 +1040us[+1581us] +/- 21ms ^* dns1.synet.edu.cn 2 6 377 53 +1040us[+1581us] +/- 21ms ^* dns1.synet.edu.cn 2 6 377 61 +1040us[+1581us] +/- 21ms ^* dns1.synet.edu.cn 2 6 377 4 -130us[ +796us] +/- 21ms ^* dns1.synet.edu.cn 2 6 377 12 -130us[ +796us] +/- 21ms ^* dns1.synet.edu.cn 2 6 377 20 -130us[ +796us] +/- 21ms

in host: MS Name/IP address Stratum Poll Reach LastRx Last sample ======================================================================== ^* 120.25.115.20 2 7 377 72 -470us[ -603us] +/- 18ms ^* 120.25.115.20 2 7 377 92 -470us[ -603us] +/- 18ms ^* 120.25.115.20 2 7 377 112 -470us[ -603us] +/- 18ms ^* 120.25.115.20 2 7 377 2 +872ns[-6808ns] +/- 17ms ^* 120.25.115.20 2 7 377 22 +872ns[-6808ns] +/- 17ms ^* 120.25.115.20 2 7 377 43 +872ns[-6808ns] +/- 17ms ^* 120.25.115.20 2 7 377 63 +872ns[-6808ns] +/- 17ms ^* 120.25.115.20 2 7 377 83 +872ns[-6808ns] +/- 17ms ^* 120.25.115.20 2 7 377 103 +872ns[-6808ns] +/- 17ms ^* 120.25.115.20 2 7 377 123 +872ns[-6808ns] +/- 17ms

The dns1.synet.edu.cn is the network reference clock for guest and 120.25.115.20 is the network reference clock for host. we can't get the clock error between guest and host directly, but a roughly estimated value will be in order of hundreds of us to ms.

with kvm ptp in guest: chrony has been disabled in host to remove the disturb by network clock.

MS Name/IP address Stratum Poll Reach LastRx Last sample ======================================================================== * PHC0 0 3 377 8 -7ns[ +1ns] +/- 3ns * PHC0 0 3 377 8 +1ns[ +16ns] +/- 3ns * PHC0 0 3 377 6 -4ns[ -0ns] +/- 6ns * PHC0 0 3 377 6 -8ns[ -12ns] +/- 5ns * PHC0 0 3 377 5 +2ns[ +4ns] +/- 4ns * PHC0 0 3 377 13 +2ns[ +4ns] +/- 4ns * PHC0 0 3 377 12 -4ns[ -6ns] +/- 4ns * PHC0 0 3 377 11 -8ns[ -11ns] +/- 6ns * PHC0 0 3 377 10 -14ns[ -20ns] +/- 4ns * PHC0 0 3 377 8 +4ns[ +5ns] +/- 4ns

The PHC0 is the ptp clock which choose the host clock as its source clock. So we can see that the clock difference between host and guest is in order of ns.

Cc: Mark Rutland mark.rutland@arm.com Acked-by: Richard Cochran richardcochran@gmail.com Signed-off-by: Jianyong Wu jianyong.wu@arm.com Signed-off-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20201209060932.212364-8-jianyong.wu@arm.com Signed-off-by: Kunkun Jiang jiangkunkun@huawei.com Signed-off-by: Dongxu Sun sundongxu3@huawei.com --- drivers/clocksource/arm_arch_timer.c | 34 ++++++++++++++++++++++++++++ drivers/ptp/Kconfig | 2 +- drivers/ptp/Makefile | 1 + drivers/ptp/ptp_kvm_arm.c | 28 +++++++++++++++++++++++ 4 files changed, 64 insertions(+), 1 deletion(-) create mode 100644 drivers/ptp/ptp_kvm_arm.c

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index d01c70d45c3f..3cc8c7d4c7df 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -25,6 +25,8 @@ #include <linux/sched/clock.h> #include <linux/sched_clock.h> #include <linux/acpi.h> +#include <linux/arm-smccc.h> +#include <linux/ptp_kvm.h>

#include <asm/arch_timer.h> #include <asm/virt.h> @@ -1723,3 +1725,35 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table) } TIMER_ACPI_DECLARE(arch_timer, ACPI_SIG_GTDT, arch_timer_acpi_init); #endif + +int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *ts, + struct clocksource **cs) +{ + struct arm_smccc_res hvc_res; + u32 ptp_counter; + ktime_t ktime; + + if (!IS_ENABLED(CONFIG_HAVE_ARM_SMCCC_DISCOVERY)) + return -EOPNOTSUPP; + + if (arch_timer_uses_ppi == ARCH_TIMER_VIRT_PPI) + ptp_counter = KVM_PTP_VIRT_COUNTER; + else + ptp_counter = KVM_PTP_PHYS_COUNTER; + + arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID, + ptp_counter, &hvc_res); + + if ((int)(hvc_res.a0) < 0) + return -EOPNOTSUPP; + + ktime = (u64)hvc_res.a0 << 32 | hvc_res.a1; + *ts = ktime_to_timespec64(ktime); + if (cycle) + *cycle = (u64)hvc_res.a2 << 32 | hvc_res.a3; + if (cs) + *cs = &clocksource_counter; + + return 0; +} +EXPORT_SYMBOL_GPL(kvm_arch_ptp_get_crosststamp); diff --git a/drivers/ptp/Kconfig b/drivers/ptp/Kconfig index cf64c3e8fb86..e834648d141c 100644 --- a/drivers/ptp/Kconfig +++ b/drivers/ptp/Kconfig @@ -109,7 +109,7 @@ config PTP_1588_CLOCK_PCH config PTP_1588_CLOCK_KVM tristate "KVM virtual PTP clock" depends on PTP_1588_CLOCK - depends on KVM_GUEST && X86 + depends on (KVM_GUEST && X86) || (HAVE_ARM_SMCCC_DISCOVERY && ARM_ARCH_TIMER) default y help This driver adds support for using kvm infrastructure as a PTP diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile index c62723b9edf5..67e260be595b 100644 --- a/drivers/ptp/Makefile +++ b/drivers/ptp/Makefile @@ -5,6 +5,7 @@

ptp-y := ptp_clock.o ptp_chardev.o ptp_sysfs.o ptp_kvm-$(CONFIG_X86) := ptp_kvm_x86.o ptp_kvm_common.o +ptp_kvm-$(CONFIG_HAVE_ARM_SMCCC) := ptp_kvm_arm.o ptp_kvm_common.o obj-$(CONFIG_PTP_1588_CLOCK) += ptp.o obj-$(CONFIG_PTP_1588_CLOCK_DTE) += ptp_dte.o obj-$(CONFIG_PTP_1588_CLOCK_INES) += ptp_ines.o diff --git a/drivers/ptp/ptp_kvm_arm.c b/drivers/ptp/ptp_kvm_arm.c new file mode 100644 index 000000000000..b7d28c8dfb84 --- /dev/null +++ b/drivers/ptp/ptp_kvm_arm.c @@ -0,0 +1,28 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Virtual PTP 1588 clock for use with KVM guests + * Copyright (C) 2019 ARM Ltd. + * All Rights Reserved + */ + +#include <linux/arm-smccc.h> +#include <linux/ptp_kvm.h> + +#include <asm/arch_timer.h> +#include <asm/hypervisor.h> + +int kvm_arch_ptp_init(void) +{ + int ret; + + ret = kvm_arm_hyp_service_available(ARM_SMCCC_KVM_FUNC_PTP); + if (ret <= 0) + return -EOPNOTSUPP; + + return 0; +} + +int kvm_arch_ptp_get_clock(struct timespec64 *ts) +{ + return kvm_arch_ptp_get_crosststamp(NULL, ts, NULL); +}

From: Zenghui Yu yuzenghui@huawei.com

mainline inclusion from mainline-v5.13-rc1 commit 182a71a3653c4324672fd87e4384fae2fbd63269 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8DWT1 CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...

--------------------------------

Per include/linux/arm-smccc.h, the Function ID of PTP_KVM service is defined as ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID. Fix the typo in documentation to keep the git grep consistent.

Signed-off-by: Zenghui Yu yuzenghui@huawei.com Signed-off-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20210417113804.1992-1-yuzenghui@huawei.com Signed-off-by: Dongxu Sun sundongxu3@huawei.com --- Documentation/virt/kvm/arm/ptp_kvm.rst | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Documentation/virt/kvm/arm/ptp_kvm.rst b/Documentation/virt/kvm/arm/ptp_kvm.rst index 68cffb50d8bf..5fbed2e51c1a 100644 --- a/Documentation/virt/kvm/arm/ptp_kvm.rst +++ b/Documentation/virt/kvm/arm/ptp_kvm.rst @@ -7,11 +7,11 @@ PTP_KVM is used for high precision time sync between host and guests. It relies on transferring the wall clock and counter value from the host to the guest using a KVM-specific hypercall.

-* ARM_SMCCC_HYP_KVM_PTP_FUNC_ID: 0x86000001 +* ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID: 0x86000001

This hypercall uses the SMC32/HVC32 calling convention:

-ARM_SMCCC_HYP_KVM_PTP_FUNC_ID +ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID ============= ========== ========== Function ID: (uint32) 0x86000001 Arguments: (uint32) KVM_PTP_VIRT_COUNTER(0)

From: Yanan Wang wangyanan55@huawei.com

virt inclusion category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8DWT1 CVE: NA

--------------------------------

fix compile error/warning

Signed-off-by: Kunkun Jiang jiangkunkun@huawei.com Signed-off-by: Dongxu Sun sundongxu3@huawei.com --- arch/arm64/include/asm/kvm_para.h | 2 +- arch/arm64/include/uapi/asm/Kbuild | 2 +- arch/arm64/include/uapi/asm/kvm_para.h | 7 +++++++ 3 files changed, 9 insertions(+), 2 deletions(-) create mode 100644 arch/arm64/include/uapi/asm/kvm_para.h

diff --git a/arch/arm64/include/asm/kvm_para.h b/arch/arm64/include/asm/kvm_para.h index e1ecc089ee9b..1e3786fe244f 100644 --- a/arch/arm64/include/asm/kvm_para.h +++ b/arch/arm64/include/asm/kvm_para.h @@ -2,7 +2,7 @@ #ifndef _ASM_ARM64_KVM_PARA_H #define _ASM_ARM64_KVM_PARA_H

-#define KVM_HINTS_REALTIME 0 +#include <uapi/asm/kvm_para.h>

static inline bool kvm_check_and_clear_guest_paused(void) { diff --git a/arch/arm64/include/uapi/asm/Kbuild b/arch/arm64/include/uapi/asm/Kbuild index 602d137932dc..28b7a35ebcc5 100644 --- a/arch/arm64/include/uapi/asm/Kbuild +++ b/arch/arm64/include/uapi/asm/Kbuild @@ -1,3 +1,3 @@ # SPDX-License-Identifier: GPL-2.0

-generic-y += kvm_para.h +#generic-y += kvm_para.h diff --git a/arch/arm64/include/uapi/asm/kvm_para.h b/arch/arm64/include/uapi/asm/kvm_para.h new file mode 100644 index 000000000000..98832b7837ee --- /dev/null +++ b/arch/arm64/include/uapi/asm/kvm_para.h @@ -0,0 +1,7 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef _UAPI_ASM_ARM64_KVM_PARA_H +#define _UAPI_ASM_ARM64_KVM_PARA_H + +#define KVM_HINTS_REALTIME 0 + +#endif /* _UAPI_ASM_ARM64_KVM_PARA_H */