diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2016-06-17 18:48:56 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2016-06-23 20:17:30 +0300 |
| commit | 87aeb54f1b9891cf08b84b3f0c34f220a4977c4f (patch) | |
| tree | 2479e2868c197f2a2e452d386606ef213fd6e61d | |
| parent | c45dcc71b794b5a346a43ad83bdcfac2138f0a2c (diff) | |
| download | linux-87aeb54f1b9891cf08b84b3f0c34f220a4977c4f.tar.xz | |
kvm: x86: use getboottime64
KVM reads the current boottime value as a struct timespec in order to
calculate the guest wallclock time, resulting in an overflow in 2038
on 32-bit systems.
The data then gets passed as an unsigned 32-bit number to the guest,
and that in turn overflows in 2106.
We cannot do much about the second overflow, which affects both 32-bit
and 64-bit hosts, but we can ensure that they both behave the same
way and don't overflow until 2106, by using getboottime64() to read
a timespec64 value.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/x86.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 0a42fc729ff3..9e50e2ad6d08 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1165,7 +1165,7 @@ static void kvm_write_wall_clock(struct kvm *kvm, gpa_t wall_clock) int version; int r; struct pvclock_wall_clock wc; - struct timespec boot; + struct timespec64 boot; if (!wall_clock) return; @@ -1188,13 +1188,13 @@ static void kvm_write_wall_clock(struct kvm *kvm, gpa_t wall_clock) * wall clock specified here. guest system time equals host * system time for us, thus we must fill in host boot time here. */ - getboottime(&boot); + getboottime64(&boot); if (kvm->arch.kvmclock_offset) { - struct timespec ts = ns_to_timespec(kvm->arch.kvmclock_offset); - boot = timespec_sub(boot, ts); + struct timespec64 ts = ns_to_timespec64(kvm->arch.kvmclock_offset); + boot = timespec64_sub(boot, ts); } - wc.sec = boot.tv_sec; + wc.sec = (u32)boot.tv_sec; /* overflow in 2106 guest time */ wc.nsec = boot.tv_nsec; wc.version = version; |