Commit Graph

12 Commits

Author SHA1 Message Date
Christoffer Dall
f837453d0e KVM: arm64: Introduce separate VHE/non-VHE sysreg save/restore functions
As we are about to handle system registers quite differently between VHE
and non-VHE systems.  In preparation for that, we need to split some of
the handling functions between VHE and non-VHE functionality.

For now, we simply copy the non-VHE functions, but we do change the use
of static keys for VHE and non-VHE functionality now that we have
separate functions.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 10:53:15 +00:00
Christoffer Dall
014c4c77aa KVM: arm64: Improve debug register save/restore flow
Instead of having multiple calls from the world switch path to the debug
logic, each figuring out if the dirty bit is set and if we should
save/restore the debug registers, let's just provide two hooks to the
debug save/restore functionality, one for switching to the guest
context, and one for switching to the host context, and we get the
benefit of only having to evaluate the dirty flag once on each path,
plus we give the compiler some more room to inline some of this
functionality.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 10:53:12 +00:00
Marc Zyngier
d68119864e KVM: arm/arm64: Detangle kvm_mmu.h from kvm_hyp.h
kvm_hyp.h has an odd dependency on kvm_mmu.h, which makes the
opposite inclusion impossible. Let's start with breaking that
useless dependency.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-08 15:20:43 +01:00
Christoffer Dall
688c50aa72 KVM: arm/arm64: Move timer save/restore out of the hyp code
As we are about to be lazy with saving and restoring the timer
registers, we prepare by moving all possible timer configuration logic
out of the hyp code.  All virtual timer registers can be programmed from
EL1 and since the arch timer is always a level triggered interrupt we
can safely do this with interrupts disabled in the host kernel on the
way to the guest without taking vtimer interrupts in the host kernel
(yet).

The downside is that the cntvoff register can only be programmed from
hyp mode, so we jump into hyp mode and back to program it.  This is also
safe, because the host kernel doesn't use the virtual timer in the KVM
code.  It may add a little performance performance penalty, but only
until following commits where we move this operation to vcpu load/put.

Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
2017-11-06 16:23:13 +01:00
Marc Zyngier
59da1cbfd8 KVM: arm64: vgic-v3: Add hook to handle guest GICv3 sysreg accesses at EL2
In order to start handling guest access to GICv3 system registers,
let's add a hook that will get called when we trap a system register
access. This is gated by a new static key (vgic_v3_cpuif_trap).

Tested-by: Alexander Graf <agraf@suse.de>
Acked-by: David Daney <david.daney@cavium.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-06-15 09:44:59 +01:00
Marc Zyngier
3272f0d08e arm64: KVM: Inject a vSerror if detecting a bad GICV access at EL2
If, when proxying a GICV access at EL2, we detect that the guest is
doing something silly, report an EL1 SError instead ofgnoring the
access.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08 12:53:00 +02:00
Marc Zyngier
fb5ee369cc arm64: KVM: vgic-v2: Add the GICV emulation infrastructure
In order to efficiently perform the GICV access on behalf of the
guest, we need to be able to avoid going back all the way to
the host kernel.

For this, we introduce a new hook in the world switch code,
conveniently placed just after populating the fault info.
At that point, we only have saved/restored the GP registers,
and we can quickly perform all the required checks (data abort,
translation fault, valid faulting syndrome, not an external
abort, not a PTW).

Coming back from the emulation code, we need to skip the emulated
instruction. This involves an additional bit of save/restore in
order to be able to access the guest's PC (and possibly CPSR if
this is a 32bit guest).

At this stage, no emulation code is provided.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08 12:53:00 +02:00
Marc Zyngier
fd81e6bf39 arm64: KVM: Refactor kern_hyp_va to deal with multiple offsets
As we move towards a selectable HYP VA range, it is obvious that
we don't want to test a variable to find out if we need to use
the bottom VA range, the top VA range, or use the address as is
(for VHE).

Instead, we can expand our current helper to generate the right
mask or nop with code patching. We default to using the top VA
space, with alternatives to switch to the bottom one or to nop
out the instructions.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
3f0f8830d4 arm/arm64: KVM: Remove hyp_kern_va helper
hyp_kern_va is now completely unused, so let's remove it entirely.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Shannon Zhao
b8cfadfcef arm64: perf: Move PMU register related defines to asm/perf_event.h
To use the ARMv8 PMU related register defines from the KVM code, we move
the relevant definitions to asm/perf_event.h header file and rename them
with prefix ARMV8_PMU_. This allows us to get rid of kvm_perf_event.h.

Signed-off-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-03-29 16:04:57 +01:00
Shannon Zhao
d692b8ad6e arm64: KVM: Add access handler for PMUSERENR register
This register resets as unknown in 64bit mode while it resets as zero
in 32bit mode. Here we choose to reset it as zero for consistency.

PMUSERENR_EL0 holds some bits which decide whether PMU registers can be
accessed from EL0. Add some check helpers to handle the access from EL0.

When these bits are zero, only reading PMUSERENR will trap to EL2 and
writing PMUSERENR or reading/writing other PMU registers will trap to
EL1 other than EL2 when HCR.TGE==0. To current KVM configuration
(HCR.TGE==0) there is no way to get these traps. Here we write 0xf to
physical PMUSERENR register on VM entry, so that it will trap PMU access
from EL0 to EL2. Within the register access handler we check the real
value of guest PMUSERENR register to decide whether this access is
allowed. If not allowed, return false to inject UND to guest.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Marc Zyngier
13720a56ed arm64: KVM: Move kvm/hyp/hyp.h to include/asm/kvm_hyp.h
In order to be able to move code outside of kvm/hyp, we need to make
the global hyp.h file accessible from a standard location.

include/asm/kvm_hyp.h seems good enough.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:18 +00:00