| From | Andrew Murray <> | Subject | [PATCH v2 02/18] arm64: KVM: reset E2PB correctly in MDCR_EL2 when exiting the guest(VHE) | Date | Fri, 20 Dec 2019 14:30:09 +0000 |
| |
From: Sudeep Holla <sudeep.holla@arm.com>
On VHE systems, the reset value for MDCR_EL2.E2PB=b00 which defaults to profiling buffer using the EL2 stage 1 translations. However if the guest are allowed to use profiling buffers changing E2PB settings, we need to ensure we resume back MDCR_EL2.E2PB=b00. Currently we just do bitwise '&' with MDCR_EL2_E2PB_MASK which will retain the value.
So fix it by clearing all the bits in E2PB.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Andrew Murray <andrew.murray@arm.com> --- arch/arm64/kvm/hyp/switch.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index 72fbbd86eb5e..250f13910882 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -228,9 +228,7 @@ void deactivate_traps_vhe_put(void) { u64 mdcr_el2 = read_sysreg(mdcr_el2); - mdcr_el2 &= MDCR_EL2_HPMN_MASK | - MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT | - MDCR_EL2_TPMS; + mdcr_el2 &= MDCR_EL2_HPMN_MASK | MDCR_EL2_TPMS; write_sysreg(mdcr_el2, mdcr_el2); -- 2.21.0
|