Commit 02d50cda authored Jun 12, 2017 by Hu Huajun Committed by Marc Zyngier Jun 15, 2017

KVM: ARM64: fix phy counter access failure in guest.



When reading the cntpct_el0 in guest with VHE (Virtual Host Extension)
enabled in host, the "Unsupported guest sys_reg access" error reported.
The reason is cnthctl_el2.EL1PCTEN is not enabled, which is expected
to be done in kvm_timer_init_vhe(). The problem is kvm_timer_init_vhe
is called by cpu_init_hyp_mode, and which is called when VHE is disabled.
This patch remove the incorrect call to kvm_timer_init_vhe() from
cpu_init_hyp_mode(), and calls kvm_timer_init_vhe() to enable
cnthctl_el2.EL1PCTEN in cpu_hyp_reinit().

Fixes: 488f94d7 ("KVM: arm64: Access CNTHCTL_EL2 bit fields correctly on VHE systems")
Cc: stable@vger.kernel.org
Signed-off-by: Hu Huajun <huhuajun@huawei.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>

parent 0959db6c

virt/kvm/arm/arm.c

+1 −3

Original line number	Diff line number	Diff line
		@@ -1141,9 +1141,6 @@ static void cpu_init_hyp_mode(void *dummy)
		__cpu_init_hyp_mode(pgd_ptr, hyp_stack_ptr, vector_ptr);
		__cpu_init_stage2();

		if (is_kernel_in_hyp_mode())
		kvm_timer_init_vhe();

		kvm_arm_init_debug();
		}

		@@ -1163,6 +1160,7 @@ static void cpu_hyp_reinit(void)
		* event was cancelled before the CPU was reset.
		*/
		__cpu_init_stage2();
		kvm_timer_init_vhe();
		} else {
		cpu_init_hyp_mode(NULL);
		}

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