x86/vmware: Skip lapic calibration on VMware
authorRenat Valiullin <rvaliullin@vmware.com>
Tue, 4 Oct 2016 20:11:48 +0000 (13:11 -0700)
committerThomas Gleixner <tglx@linutronix.de>
Wed, 5 Oct 2016 09:43:30 +0000 (11:43 +0200)
commitb91688f528fe96e09d17e6d87c1b2805eb0c445e
tree46e3f194c51b91b153193480cd977105e3b67fda
parent2df0e78b44e2cbbaa1e319cbca34f23599a4daa0
x86/vmware: Skip lapic calibration on VMware

In a virtualized environment the APIC timer calibration can go wrong when
the host is overcommitted or the guest is running nested. This results
in the APIC timers operating at an incorrect frequency.

Since VMware supports a mechanism to retrieve the local APIC frequency we
can ask the hypervisor for it and skip the APIC calibration loop.

Signed-off-by: Renat Valiullin <rvaliullin@vmware.com>
Acked-by: Alok N Kataria <akataria@vmware.com>
Cc: virtualization@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/20161004201148.GA1421@uu64vm
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
arch/x86/kernel/cpu/vmware.c