[PATCH] arm64: KVM: Fix user access for debug registers

[Christoffer Dall]

On Wed, Sep 16, 2015 at 11:41:10AM +0100, Marc Zyngier wrote:
> When setting the debug register from userspace, make sure that
> copy_from_user() is called with its parameters in the expected
> order. It otherwise doesn't do what you think.
> 
> Reported-by: Peter Maydell <peter.maydell at linaro.org>
> Cc: Alex Bennée <alex.bennee at linaro.org>
> Fixes: 84e690bfbed1 ("KVM: arm64: introduce vcpu->arch.debug_ptr")
> Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>

yikes!

Reviewed-by: Christoffer Dall <christoffer.dall at linaro.org>