Commit 0e6edceb authored May 20, 2019 by Wanpeng Li Committed by Paolo Bonzini May 24, 2019

KVM: LAPIC: Fix lapic_timer_advance_ns parameter overflow



After commit c3941d9e (KVM: lapic: Allow user to disable adaptive tuning of
timer advancement), '-1' enables adaptive tuning starting from default
advancment of 1000ns. However, we should expose an int instead of an overflow
uint module parameter.

Before patch:

/sys/module/kvm/parameters/lapic_timer_advance_ns:4294967295

After patch:

/sys/module/kvm/parameters/lapic_timer_advance_ns:-1

Fixes: c3941d9e (KVM: lapic: Allow user to disable adaptive tuning of timer advancement)
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

parent 4d259965

arch/x86/kvm/x86.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -143,7 +143,7 @@ module_param(tsc_tolerance_ppm, uint, S_IRUGO \| S_IWUSR);
		* tuning, i.e. allows priveleged userspace to set an exact advancement time.
		*/
		static int __read_mostly lapic_timer_advance_ns = -1;
		module_param(lapic_timer_advance_ns, uint, S_IRUGO \| S_IWUSR);
		module_param(lapic_timer_advance_ns, int, S_IRUGO \| S_IWUSR);

		static bool __read_mostly vector_hashing = true;
		module_param(vector_hashing, bool, S_IRUGO);

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