arm64: head.S: initialise mdcr_el2 in el2_setup
authorWill Deacon <will.deacon@arm.com>
Wed, 2 Sep 2015 17:49:28 +0000 (18:49 +0100)
committerWill Deacon <will.deacon@arm.com>
Tue, 15 Sep 2015 14:50:01 +0000 (15:50 +0100)
commitd10bcd473301888f957ec4b6b12aa3621be78d59
treea9297efb6b822cbfd6dca8101d3dfd4dba92faea
parent2314ee4d444e28d4670ff80c84df68c25887decb
arm64: head.S: initialise mdcr_el2 in el2_setup

When entering the kernel at EL2, we fail to initialise the MDCR_EL2
register which controls debug access and PMU capabilities at EL1.

This patch ensures that the register is initialised so that all traps
are disabled and all the PMU counters are available to the host. When a
guest is scheduled, KVM takes care to configure trapping appropriately.

Cc: <stable@vger.kernel.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arch/arm64/kernel/head.S