xavi/android_kernel_m2note/arch/arm64/kernel/head.S, branch o-8.1

arm64: head.S: remove unnecessary function alignment

2016-09-10T10:06:59+00:00

Currently __turn_mmu_on is aligned to 64 bytes to ensure that it doesn't span any page boundary, which simplifies the idmap and spares us requiring an additional page table to map half of the function. In keeping with other important requirements in architecture code, this fact is undocumented. Additionally, as the function consists of three instructions totalling 12 bytes with no literal pool data, a smaller alignment of 16 bytes would be sufficient. This patch reduces the alignment to 16 bytes and documents the underlying reason for the alignment. This reduces the required alignment of the entire .head.text section from 64 bytes to 16 bytes, though it may still be aligned to a larger value depending on TEXT_OFFSET. Signed-off-by: Mark Rutland Tested-by: Laura Abbott Acked-by: Will Deacon Signed-off-by: Catalin Marinas Git-commit: 909a4069da65a5cfca8c968edf9f0d99f694d2f3 Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git Signed-off-by: David Keitel Change-Id: Ib41fc73a0d1a28e4b1a67f84f1bbe8cf9920aa5b Signed-off-by: franciscofranco

arm64: head.S: initialise mdcr_el2 in el2_setup

2016-08-26T18:01:58+00:00

commit d10bcd473301888f957ec4b6b12aa3621be78d59 upstream. 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. Acked-by: Marc Zyngier Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman Signed-off-by: Stefan Guendhoer

first commit

2016-08-15T02:19:42+00:00