From 001f60e1f662a6dee1630a2915401aaf5959d479 Mon Sep 17 00:00:00 2001 From: Joao Martins Date: Wed, 8 Nov 2017 17:19:54 +0000 Subject: ptp_kvm: probe for kvm guest availability In the event of moving pvclock_pvti_cpu0_va() definition to common pvclock code, this function would return a value on non KVM guests. Later on this would fail with a GPF on ptp_kvm_init when running on a Xen guest. Therefore, ptp_kvm_init() should check whether it is running in a KVM guest. Signed-off-by: Joao Martins Acked-by: Radim Krčmář Signed-off-by: Boris Ostrovsky --- drivers/ptp/ptp_kvm.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/ptp') diff --git a/drivers/ptp/ptp_kvm.c b/drivers/ptp/ptp_kvm.c index 2b1b212c219e..e04d7b2ecb3a 100644 --- a/drivers/ptp/ptp_kvm.c +++ b/drivers/ptp/ptp_kvm.c @@ -178,6 +178,9 @@ static int __init ptp_kvm_init(void) { long ret; + if (!kvm_para_available()) + return -ENODEV; + clock_pair_gpa = slow_virt_to_phys(&clock_pair); hv_clock = pvclock_pvti_cpu0_va(); -- cgit v1.2.3-55-g7522 From 9f08890ab906abaf9d4c1bad8111755cbd302260 Mon Sep 17 00:00:00 2001 From: Joao Martins Date: Wed, 8 Nov 2017 17:19:55 +0000 Subject: x86/pvclock: add setter for pvclock_pvti_cpu0_va Right now there is only a pvclock_pvti_cpu0_va() which is defined on kvmclock since: commit dac16fba6fc5 ("x86/vdso: Get pvclock data from the vvar VMA instead of the fixmap") The only user of this interface so far is kvm. This commit adds a setter function for the pvti page and moves pvclock_pvti_cpu0_va to pvclock, which is a more generic place to have it; and would allow other PV clocksources to use it, such as Xen. While moving pvclock_pvti_cpu0_va into pvclock, rename also this function to pvclock_get_pvti_cpu0_va (including its call sites) to be symmetric with the setter (pvclock_set_pvti_cpu0_va). Signed-off-by: Joao Martins Acked-by: Andy Lutomirski Acked-by: Paolo Bonzini Acked-by: Thomas Gleixner Signed-off-by: Boris Ostrovsky --- arch/x86/entry/vdso/vma.c | 2 +- arch/x86/include/asm/pvclock.h | 19 ++++++++++--------- arch/x86/kernel/kvmclock.c | 7 +------ arch/x86/kernel/pvclock.c | 14 ++++++++++++++ drivers/ptp/ptp_kvm.c | 2 +- 5 files changed, 27 insertions(+), 17 deletions(-) (limited to 'drivers/ptp') diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c index 1911310959f8..a77fd3c8d824 100644 --- a/arch/x86/entry/vdso/vma.c +++ b/arch/x86/entry/vdso/vma.c @@ -112,7 +112,7 @@ static int vvar_fault(const struct vm_special_mapping *sm, __pa_symbol(&__vvar_page) >> PAGE_SHIFT); } else if (sym_offset == image->sym_pvclock_page) { struct pvclock_vsyscall_time_info *pvti = - pvclock_pvti_cpu0_va(); + pvclock_get_pvti_cpu0_va(); if (pvti && vclock_was_used(VCLOCK_PVCLOCK)) { ret = vm_insert_pfn( vma, diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h index 448cfe1b48cf..55325f934d71 100644 --- a/arch/x86/include/asm/pvclock.h +++ b/arch/x86/include/asm/pvclock.h @@ -4,15 +4,6 @@ #include #include -#ifdef CONFIG_KVM_GUEST -extern struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void); -#else -static inline struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void) -{ - return NULL; -} -#endif - /* some helper functions for xen and kvm pv clock sources */ u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src); u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src); @@ -101,4 +92,14 @@ struct pvclock_vsyscall_time_info { #define PVTI_SIZE sizeof(struct pvclock_vsyscall_time_info) +#ifdef CONFIG_PARAVIRT_CLOCK +void pvclock_set_pvti_cpu0_va(struct pvclock_vsyscall_time_info *pvti); +struct pvclock_vsyscall_time_info *pvclock_get_pvti_cpu0_va(void); +#else +static inline struct pvclock_vsyscall_time_info *pvclock_get_pvti_cpu0_va(void) +{ + return NULL; +} +#endif + #endif /* _ASM_X86_PVCLOCK_H */ diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index d88967659098..538738047ff5 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -47,12 +47,6 @@ early_param("no-kvmclock", parse_no_kvmclock); static struct pvclock_vsyscall_time_info *hv_clock; static struct pvclock_wall_clock wall_clock; -struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void) -{ - return hv_clock; -} -EXPORT_SYMBOL_GPL(pvclock_pvti_cpu0_va); - /* * The wallclock is the time of day when we booted. Since then, some time may * have elapsed since the hypervisor wrote the data. So we try to account for @@ -334,6 +328,7 @@ int __init kvm_setup_vsyscall_timeinfo(void) return 1; } + pvclock_set_pvti_cpu0_va(hv_clock); put_cpu(); kvm_clock.archdata.vclock_mode = VCLOCK_PVCLOCK; diff --git a/arch/x86/kernel/pvclock.c b/arch/x86/kernel/pvclock.c index 5c3f6d6a5078..761f6af6efa5 100644 --- a/arch/x86/kernel/pvclock.c +++ b/arch/x86/kernel/pvclock.c @@ -25,8 +25,10 @@ #include #include +#include static u8 valid_flags __read_mostly = 0; +static struct pvclock_vsyscall_time_info *pvti_cpu0_va __read_mostly; void pvclock_set_flags(u8 flags) { @@ -144,3 +146,15 @@ void pvclock_read_wallclock(struct pvclock_wall_clock *wall_clock, set_normalized_timespec(ts, now.tv_sec, now.tv_nsec); } + +void pvclock_set_pvti_cpu0_va(struct pvclock_vsyscall_time_info *pvti) +{ + WARN_ON(vclock_was_used(VCLOCK_PVCLOCK)); + pvti_cpu0_va = pvti; +} + +struct pvclock_vsyscall_time_info *pvclock_get_pvti_cpu0_va(void) +{ + return pvti_cpu0_va; +} +EXPORT_SYMBOL_GPL(pvclock_get_pvti_cpu0_va); diff --git a/drivers/ptp/ptp_kvm.c b/drivers/ptp/ptp_kvm.c index e04d7b2ecb3a..c67dd11e08b1 100644 --- a/drivers/ptp/ptp_kvm.c +++ b/drivers/ptp/ptp_kvm.c @@ -182,7 +182,7 @@ static int __init ptp_kvm_init(void) return -ENODEV; clock_pair_gpa = slow_virt_to_phys(&clock_pair); - hv_clock = pvclock_pvti_cpu0_va(); + hv_clock = pvclock_get_pvti_cpu0_va(); if (!hv_clock) return -ENODEV; -- cgit v1.2.3-55-g7522