Will this be MFCed to stable/13 ? I'd really really like to have it in 13.1 since it fixes a regression in EC2.
Colin Percival On 8/14/21 5:58 AM, Konstantin Belousov wrote: > The branch main has been updated by kib: > > URL: > https://cgit.FreeBSD.org/src/commit/?id=6c69c6bb4c7ffde48b130df707799d4eca21ca9f > > commit 6c69c6bb4c7ffde48b130df707799d4eca21ca9f > Author: Adam Fenn <[email protected]> > AuthorDate: 2021-08-04 15:42:48 +0000 > Commit: Konstantin Belousov <[email protected]> > CommitDate: 2021-08-14 12:57:54 +0000 > > kvm_clock: KVM paravirtual clock support > > Add support for the KVM paravirtual clock device. > > Sponsored by: Juniper Networks, Inc. > Sponsored by: Klara, Inc. > Reviewed by: kib > Differential Revision: https://reviews.freebsd.org/D29733 > --- > sys/amd64/conf/GENERIC | 3 + > sys/amd64/conf/MINIMAL | 3 + > sys/amd64/conf/NOTES | 3 + > sys/conf/files.x86 | 3 +- > sys/dev/kvm_clock/kvm_clock.c | 240 > ++++++++++++++++++++++++++++++++++++++++++ > sys/i386/conf/GENERIC | 3 + > sys/i386/conf/MINIMAL | 3 + > sys/i386/conf/NOTES | 3 + > sys/x86/include/kvm.h | 80 ++++++++++++++ > 9 files changed, 340 insertions(+), 1 deletion(-) > > diff --git a/sys/amd64/conf/GENERIC b/sys/amd64/conf/GENERIC > index f7b41919575d..78b5e0e299f6 100644 > --- a/sys/amd64/conf/GENERIC > +++ b/sys/amd64/conf/GENERIC > @@ -376,6 +376,9 @@ device virtio_blk # VirtIO Block > device > device virtio_scsi # VirtIO SCSI device > device virtio_balloon # VirtIO Memory Balloon device > > +# Linux KVM paravirtualization support > +device kvm_clock # KVM paravirtual clock driver > + > # HyperV drivers and enhancement support > device hyperv # HyperV drivers > > diff --git a/sys/amd64/conf/MINIMAL b/sys/amd64/conf/MINIMAL > index 14f91e6c8eaf..f724cbd2e3f1 100644 > --- a/sys/amd64/conf/MINIMAL > +++ b/sys/amd64/conf/MINIMAL > @@ -131,6 +131,9 @@ device ether # Ethernet > support > # Note that 'bpf' is required for DHCP. > device bpf # Berkeley packet filter > > +# Linux KVM paravirtualization support > +device kvm_clock # KVM paravirtual clock driver > + > # Xen HVM Guest Optimizations > # NOTE: XENHVM depends on xenpci and xentimer. > # They must be added or removed together. > diff --git a/sys/amd64/conf/NOTES b/sys/amd64/conf/NOTES > index 501ceaedb222..c1db8ef7512f 100644 > --- a/sys/amd64/conf/NOTES > +++ b/sys/amd64/conf/NOTES > @@ -498,6 +498,9 @@ device virtio_balloon # VirtIO Memory Balloon > device > device virtio_random # VirtIO Entropy device > device virtio_console # VirtIO Console device > > +# Linux KVM paravirtualization support > +device kvm_clock # KVM paravirtual clock driver > + > # Microsoft Hyper-V enhancement support > device hyperv # HyperV drivers > > diff --git a/sys/conf/files.x86 b/sys/conf/files.x86 > index d1fc234c4182..d0cda2da8580 100644 > --- a/sys/conf/files.x86 > +++ b/sys/conf/files.x86 > @@ -263,6 +263,7 @@ dev/isci/scil/scif_sas_task_request_state_handlers.c > optional isci > dev/isci/scil/scif_sas_task_request_states.c optional isci > dev/isci/scil/scif_sas_timer.c > optional isci > dev/itwd/itwd.c > optional itwd > +dev/kvm_clock/kvm_clock.c optional kvm_clock > dev/qat/qat.c optional qat > dev/qat/qat_ae.c optional qat > dev/qat/qat_c2xxx.c optional qat > @@ -318,7 +319,7 @@ x86/x86/x86_mem.c optional mem > x86/x86/mp_x86.c optional smp > x86/x86/mp_watchdog.c optional mp_watchdog smp > x86/x86/nexus.c standard > -x86/x86/pvclock.c optional xenhvm > +x86/x86/pvclock.c optional kvm_clock | xenhvm > x86/x86/stack_machdep.c optional ddb | stack > x86/x86/tsc.c standard > x86/x86/ucode.c standard > diff --git a/sys/dev/kvm_clock/kvm_clock.c b/sys/dev/kvm_clock/kvm_clock.c > new file mode 100644 > index 000000000000..1a76432e417d > --- /dev/null > +++ b/sys/dev/kvm_clock/kvm_clock.c > @@ -0,0 +1,240 @@ > +/*- > + * SPDX-License-Identifier: BSD-2-Clause-FreeBSD > + * > + * Copyright (c) 2014 Bryan Venteicher <[email protected]> > + * Copyright (c) 2021 Mathieu Chouquet-Stringer > + * Copyright (c) 2021 Juniper Networks, Inc. > + * Copyright (c) 2021 Klara, Inc. > + * > + * Redistribution and use in source and binary forms, with or without > + * modification, are permitted provided that the following conditions > + * are met: > + * 1. Redistributions of source code must retain the above copyright > + * notice, this list of conditions and the following disclaimer. > + * 2. Redistributions in binary form must reproduce the above copyright > + * notice, this list of conditions and the following disclaimer in the > + * documentation and/or other materials provided with the distribution. > + * > + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND > + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE > + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE > + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE > + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL > + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS > + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) > + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT > + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY > + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF > + * SUCH DAMAGE. > + */ > + > +/* > + * Linux KVM paravirtual clock support > + * > + * References: > + * - [1] https://www.kernel.org/doc/html/latest/virt/kvm/cpuid.html > + * - [2] https://www.kernel.org/doc/html/latest/virt/kvm/msr.html > + */ > + > +#include <sys/cdefs.h> > +__FBSDID("$FreeBSD$"); > + > +#include <sys/param.h> > +#include <sys/bus.h> > +#include <sys/domainset.h> > +#include <sys/kernel.h> > +#include <sys/malloc.h> > +#include <sys/module.h> > +#include <sys/smp.h> > + > +#include <vm/vm.h> > +#include <vm/pmap.h> > +#include <vm/vm_extern.h> > + > +#include <machine/pvclock.h> > +#include <x86/kvm.h> > + > +#include "clock_if.h" > + > +#define KVM_CLOCK_DEVNAME "kvmclock" > +/* > + * Note: Chosen to be (1) above HPET's value (always 950), (2) above the > TSC's > + * default value of 800, and (3) below the TSC's value when it supports the > + * "Invariant TSC" feature and is believed to be synchronized across all > CPUs. > + */ > +#define KVM_CLOCK_TC_QUALITY 975 > + > +struct kvm_clock_softc { > + struct pvclock pvc; > + struct pvclock_wall_clock wc; > + struct pvclock_vcpu_time_info *timeinfos; > + u_int msr_tc; > + u_int msr_wc; > +}; > + > +static devclass_t kvm_clock_devclass; > + > +static struct pvclock_wall_clock *kvm_clock_get_wallclock(void *arg); > +static void kvm_clock_system_time_enable(struct kvm_clock_softc *sc); > +static void kvm_clock_system_time_enable_pcpu(void *arg); > + > +static struct pvclock_wall_clock * > +kvm_clock_get_wallclock(void *arg) > +{ > + struct kvm_clock_softc *sc = arg; > + > + wrmsr(sc->msr_wc, vtophys(&sc->wc)); > + return (&sc->wc); > +} > + > +static void > +kvm_clock_system_time_enable(struct kvm_clock_softc *sc) > +{ > + smp_rendezvous(NULL, kvm_clock_system_time_enable_pcpu, NULL, sc); > +} > + > +static void > +kvm_clock_system_time_enable_pcpu(void *arg) > +{ > + struct kvm_clock_softc *sc = arg; > + > + /* > + * See [2]; the lsb of this MSR is the system time enable bit. > + */ > + wrmsr(sc->msr_tc, vtophys(&(sc->timeinfos)[curcpu]) | 1); > +} > + > +static void > +kvm_clock_identify(driver_t *driver, device_t parent) > +{ > + u_int regs[4]; > + > + kvm_cpuid_get_features(regs); > + if ((regs[0] & > + (KVM_FEATURE_CLOCKSOURCE2 | KVM_FEATURE_CLOCKSOURCE)) == 0) > + return; > + if (device_find_child(parent, KVM_CLOCK_DEVNAME, -1)) > + return; > + BUS_ADD_CHILD(parent, 0, KVM_CLOCK_DEVNAME, 0); > +} > + > +static int > +kvm_clock_probe(device_t dev) > +{ > + device_set_desc(dev, "KVM paravirtual clock"); > + return (BUS_PROBE_DEFAULT); > +} > + > +static int > +kvm_clock_attach(device_t dev) > +{ > + u_int regs[4]; > + struct kvm_clock_softc *sc = device_get_softc(dev); > + bool stable_flag_supported; > + > + /* Process KVM "features" CPUID leaf content: */ > + kvm_cpuid_get_features(regs); > + if ((regs[0] & KVM_FEATURE_CLOCKSOURCE2) != 0) { > + sc->msr_tc = KVM_MSR_SYSTEM_TIME_NEW; > + sc->msr_wc = KVM_MSR_WALL_CLOCK_NEW; > + } else { > + KASSERT((regs[0] & KVM_FEATURE_CLOCKSOURCE) != 0, > + ("Clocksource feature flags disappeared since " > + "kvm_clock_identify: regs[0] %#0x.", regs[0])); > + sc->msr_tc = KVM_MSR_SYSTEM_TIME; > + sc->msr_wc = KVM_MSR_WALL_CLOCK; > + } > + stable_flag_supported = > + (regs[0] & KVM_FEATURE_CLOCKSOURCE_STABLE_BIT) != 0; > + > + /* Set up 'struct pvclock_vcpu_time_info' page(s): */ > + sc->timeinfos = (struct pvclock_vcpu_time_info *)kmem_malloc(mp_ncpus * > + sizeof(struct pvclock_vcpu_time_info), M_WAITOK | M_ZERO); > + kvm_clock_system_time_enable(sc); > + > + /* > + * Init pvclock; register KVM clock wall clock, register KVM clock > + * timecounter, and set up the requisite infrastructure for vDSO access > + * to this timecounter. > + * Regarding 'tc_flags': Since the KVM MSR documentation does not > + * specifically discuss suspend/resume scenarios, conservatively > + * leave 'TC_FLAGS_SUSPEND_SAFE' cleared and assume that the system > + * time must be re-inited in such cases. > + */ > + sc->pvc.get_wallclock = kvm_clock_get_wallclock; > + sc->pvc.get_wallclock_arg = sc; > + sc->pvc.timeinfos = sc->timeinfos; > + sc->pvc.stable_flag_supported = stable_flag_supported; > + pvclock_init(&sc->pvc, dev, KVM_CLOCK_DEVNAME, KVM_CLOCK_TC_QUALITY, 0); > + return (0); > +} > + > +static int > +kvm_clock_detach(device_t dev) > +{ > + struct kvm_clock_softc *sc = device_get_softc(dev); > + > + return (pvclock_destroy(&sc->pvc)); > +} > + > +static int > +kvm_clock_suspend(device_t dev) > +{ > + return (0); > +} > + > +static int > +kvm_clock_resume(device_t dev) > +{ > + /* > + * See note in 'kvm_clock_attach()' regarding 'TC_FLAGS_SUSPEND_SAFE'; > + * conservatively assume that the system time must be re-inited in > + * suspend/resume scenarios. > + */ > + kvm_clock_system_time_enable(device_get_softc(dev)); > + pvclock_resume(); > + inittodr(time_second); > + return (0); > +} > + > +static int > +kvm_clock_gettime(device_t dev, struct timespec *ts) > +{ > + struct kvm_clock_softc *sc = device_get_softc(dev); > + > + pvclock_gettime(&sc->pvc, ts); > + return (0); > +} > + > +static int > +kvm_clock_settime(device_t dev, struct timespec *ts) > +{ > + /* > + * Even though it is not possible to set the KVM clock's wall clock, to > + * avoid the possibility of periodic benign error messages from > + * 'settime_task_func()', report success rather than, e.g., 'ENODEV'. > + */ > + return (0); > +} > + > +static device_method_t kvm_clock_methods[] = { > + DEVMETHOD(device_identify, kvm_clock_identify), > + DEVMETHOD(device_probe, kvm_clock_probe), > + DEVMETHOD(device_attach, kvm_clock_attach), > + DEVMETHOD(device_detach, kvm_clock_detach), > + DEVMETHOD(device_suspend, kvm_clock_suspend), > + DEVMETHOD(device_resume, kvm_clock_resume), > + /* clock interface */ > + DEVMETHOD(clock_gettime, kvm_clock_gettime), > + DEVMETHOD(clock_settime, kvm_clock_settime), > + > + DEVMETHOD_END > +}; > + > +static driver_t kvm_clock_driver = { > + KVM_CLOCK_DEVNAME, > + kvm_clock_methods, > + sizeof(struct kvm_clock_softc), > +}; > + > +DRIVER_MODULE(kvm_clock, nexus, kvm_clock_driver, kvm_clock_devclass, 0, 0); > diff --git a/sys/i386/conf/GENERIC b/sys/i386/conf/GENERIC > index 86c062effd81..5447c452c4f7 100644 > --- a/sys/i386/conf/GENERIC > +++ b/sys/i386/conf/GENERIC > @@ -337,6 +337,9 @@ device virtio_blk # VirtIO Block > device > device virtio_scsi # VirtIO SCSI device > device virtio_balloon # VirtIO Memory Balloon device > > +# Linux KVM paravirtualization support > +device kvm_clock # KVM paravirtual clock driver > + > # HyperV drivers and enhancement support > # NOTE: HYPERV depends on hyperv. They must be added or removed together. > options HYPERV # Kernel support for HyperV drivers > diff --git a/sys/i386/conf/MINIMAL b/sys/i386/conf/MINIMAL > index 37b8e074ac65..9d735dbb0580 100644 > --- a/sys/i386/conf/MINIMAL > +++ b/sys/i386/conf/MINIMAL > @@ -145,6 +145,9 @@ device gif # IPv6 and IPv4 > tunneling > # Note that 'bpf' is required for DHCP. > device bpf # Berkeley packet filter > > +# Linux KVM paravirtualization support > +device kvm_clock # KVM paravirtual clock driver > + > # Xen HVM Guest Optimizations > # NOTE: XENHVM depends on xenpci. They must be added or removed together. > options XENHVM # Xen HVM kernel infrastructure > diff --git a/sys/i386/conf/NOTES b/sys/i386/conf/NOTES > index df9ff4fb3aed..27cebf0c48a0 100644 > --- a/sys/i386/conf/NOTES > +++ b/sys/i386/conf/NOTES > @@ -719,6 +719,9 @@ device virtio_balloon # VirtIO Memory Balloon > device > device virtio_random # VirtIO Entropy device > device virtio_console # VirtIO Console device > > +# Linux KVM paravirtualization support > +device kvm_clock # KVM paravirtual clock driver > + > options HYPERV > device hyperv # HyperV drivers > > diff --git a/sys/x86/include/kvm.h b/sys/x86/include/kvm.h > new file mode 100644 > index 000000000000..beec6447d7d6 > --- /dev/null > +++ b/sys/x86/include/kvm.h > @@ -0,0 +1,80 @@ > +/*- > + * SPDX-License-Identifier: BSD-2-Clause-FreeBSD > + * > + * Copyright (c) 2014 Bryan Venteicher <[email protected]> > + * Copyright (c) 2021 Mathieu Chouquet-Stringer > + * Copyright (c) 2021 Juniper Networks, Inc. > + * Copyright (c) 2021 Klara, Inc. > + * > + * Redistribution and use in source and binary forms, with or without > + * modification, are permitted provided that the following conditions > + * are met: > + * 1. Redistributions of source code must retain the above copyright > + * notice, this list of conditions and the following disclaimer. > + * 2. Redistributions in binary form must reproduce the above copyright > + * notice, this list of conditions and the following disclaimer in the > + * documentation and/or other materials provided with the distribution. > + * > + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND > + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE > + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE > + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE > + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL > + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS > + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) > + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT > + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY > + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF > + * SUCH DAMAGE. > + * > + * $FreeBSD$ > + */ > + > +/* > + * Linux KVM paravirtualization: common definitions > + * > + * References: > + * - [1] https://www.kernel.org/doc/html/latest/virt/kvm/cpuid.html > + * - [2] https://www.kernel.org/doc/html/latest/virt/kvm/msr.html > + */ > + > +#ifndef _X86_KVM_H_ > +#define _X86_KVM_H_ > + > +#include <sys/types.h> > +#include <sys/systm.h> > + > +#include <machine/md_var.h> > + > +#define KVM_CPUID_SIGNATURE 0x40000000 > +#define KVM_CPUID_FEATURES_LEAF 0x40000001 > + > +#define KVM_FEATURE_CLOCKSOURCE 0x00000001 > +#define KVM_FEATURE_CLOCKSOURCE2 0x00000008 > +#define KVM_FEATURE_CLOCKSOURCE_STABLE_BIT 0x01000000 > + > +/* Deprecated: for the CLOCKSOURCE feature. */ > +#define KVM_MSR_WALL_CLOCK 0x11 > +#define KVM_MSR_SYSTEM_TIME 0x12 > + > +#define KVM_MSR_WALL_CLOCK_NEW 0x4b564d00 > +#define KVM_MSR_SYSTEM_TIME_NEW 0x4b564d01 > + > +static inline bool > +kvm_cpuid_features_leaf_supported(void) > +{ > + return (vm_guest == VM_GUEST_KVM && > + KVM_CPUID_FEATURES_LEAF > hv_base && > + KVM_CPUID_FEATURES_LEAF <= hv_high); > +} > + > +static inline void > +kvm_cpuid_get_features(u_int *regs) > +{ > + if (!kvm_cpuid_features_leaf_supported()) > + regs[0] = regs[1] = regs[2] = regs[3] = 0; > + else > + do_cpuid(KVM_CPUID_FEATURES_LEAF, regs); > +} > + > +#endif /* !_X86_KVM_H_ */ > -- Colin Percival Security Officer Emeritus, FreeBSD | The power to serve Founder, Tarsnap | www.tarsnap.com | Online backups for the truly paranoid _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/dev-commits-src-all To unsubscribe, send any mail to "[email protected]"
