Commit Graph

17 Commits

Author SHA1 Message Date
Marc Zyngier
9d8415d6c1 arm64: KVM: Turn system register numbers to an enum
Having the system register numbers as #defines has been a pain
since day one, as the ordering is pretty fragile, and moving
things around leads to renumbering and epic conflict resolutions.

Now that we're mostly acessing the sysreg file in C, an enum is
a much better type to use, and we can clean things up a bit.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-12-14 11:30:43 +00:00
Amit Tomar
b19e6892a9 KVM: arm/arm64: Count guest exit due to various reasons
It would add guest exit statistics to debugfs, this can be helpful
while measuring KVM performance.

  [ Renamed some of the field names - Christoffer ]

Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-12-14 11:30:00 +00:00
Suzuki K. Poulose
bca556ac46 arm64/kvm: Add generic v8 KVM target
This patch adds a generic ARM v8 KVM target cpu type for use
by the new CPUs which eventualy ends up using the common sys_reg
table. For backward compatibility the existing targets have been
preserved. Any new target CPU that can be covered by generic v8
sys_reg tables should make use of the new generic target.

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Acked-by: Marc Zyngier <Marc.Zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:22 +01:00
Alex Bennée
eef8c85a3b KVM: arm64: add trace points for guest_debug debug
This includes trace points for:
  kvm_arch_setup_guest_debug
  kvm_arch_clear_guest_debug

I've also added some generic register setting trace events and also a
trace point to dump the array of hardware registers.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-07-21 12:50:43 +01:00
Alex Bennée
834bf88726 KVM: arm64: enable KVM_CAP_SET_GUEST_DEBUG
Finally advertise the KVM capability for SET_GUEST_DEBUG. Once arm
support is added this check can be moved to the common
kvm_vm_ioctl_check_extension() code.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-07-21 12:50:43 +01:00
Alex Bennée
337b99bf7e KVM: arm64: guest debug, add support for single-step
This adds support for single-stepping the guest. To do this we need to
manipulate the guests PSTATE.SS and MDSCR_EL1.SS bits to trigger
stepping. We take care to preserve MDSCR_EL1 and trap access to it to
ensure we don't affect the apparent state of the guest.

As we have to enable trapping of all software debug exceptions we
suppress the ability of the guest to single-step itself. If we didn't we
would have to deal with the exception arriving while the guest was in
kernelspace when the guest is expecting to single-step userspace. This
is something we don't want to unwind in the kernel. Once the host is no
longer debugging the guest its ability to single-step userspace is
restored.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-07-21 12:47:08 +01:00
Alex Bennée
4bd611ca60 KVM: arm64: guest debug, add SW break point support
This adds support for SW breakpoints inserted by userspace.

We do this by trapping all guest software debug exceptions to the
hypervisor (MDCR_EL2.TDE). The exit handler sets an exit reason of
KVM_EXIT_DEBUG with the kvm_debug_exit_arch structure holding the
exception syndrome information.

It will be up to userspace to extract the PC (via GET_ONE_REG) and
determine if the debug event was for a breakpoint it inserted. If not
userspace will need to re-inject the correct exception restart the
hypervisor to deliver the debug exception to the guest.

Any other guest software debug exception (e.g. single step or HW
assisted breakpoints) will cause an error and the VM to be killed. This
is addressed by later patches which add support for the other debug
types.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-07-21 12:47:08 +01:00
Alex Bennée
0e6f07f29c KVM: arm: guest debug, add stub KVM_SET_GUEST_DEBUG ioctl
This commit adds a stub function to support the KVM_SET_GUEST_DEBUG
ioctl. Any unsupported flag will return -EINVAL. For now, only
KVM_GUESTDBG_ENABLE is supported, although it won't have any effects.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-07-21 12:47:08 +01:00
Christoffer Dall
f7fa034dc8 arm/arm64: KVM: Clarify KVM_ARM_VCPU_INIT ABI
It is not clear that this ioctl can be called multiple times for a given
vcpu.  Userspace already does this, so clarify the ABI.

Also specify that userspace is expected to always make secondary and
subsequent calls to the ioctl with the same parameters for the VCPU as
the initial call (which userspace also already does).

Add code to check that userspace doesn't violate that ABI in the future,
and move the kvm_vcpu_set_target() function which is currently
duplicated between the 32-bit and 64-bit versions in guest.c to a common
static function in arm.c, shared between both architectures.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-13 14:15:26 +01:00
Christoffer Dall
b856a59141 arm/arm64: KVM: Reset the HCR on each vcpu when resetting the vcpu
When userspace resets the vcpu using KVM_ARM_VCPU_INIT, we should also
reset the HCR, because we now modify the HCR dynamically to
enable/disable trapping of guest accesses to the VM registers.

This is crucial for reboot of VMs working since otherwise we will not be
doing the necessary cache maintenance operations when faulting in pages
with the guest MMU off.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-13 14:15:26 +01:00
Will Deacon
bd218bce92 KVM: ARM/arm64: return -EFAULT if copy_from_user fails in set_timer_reg
We currently return the number of bytes not copied if set_timer_reg
fails, which is almost certainly not what userspace would like.

This patch returns -EFAULT instead.

Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-08-27 22:49:45 +02:00
Alex Bennée
1df08ba0aa arm64: KVM: allow export and import of generic timer regs
For correct guest suspend/resume behaviour we need to ensure we include
the generic timer registers for 64 bit guests. As CONFIG_KVM_ARM_TIMER is
always set for arm64 we don't need to worry about null implementations.
However I have re-jigged the kvm_arm_timer_set/get_reg declarations to
be in the common include/kvm/arm_arch_timer.h headers.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-07-11 04:46:55 -07:00
Marc Zyngier
1252b33136 arm64: KVM: Enable minimalistic support for Cortex-A53
In order to allow KVM to run on Cortex-A53 implementations, wire the
minimal support required.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-05-25 20:05:30 +02:00
Anup Patel
e28100bd8e arm64: KVM: Support X-Gene guest VCPU on APM X-Gene host
This patch allows us to have X-Gene guest VCPU when using KVM arm64
on APM X-Gene host.

We add KVM_ARM_TARGET_XGENE_POTENZA for X-Gene Potenza compatible
guest VCPU and we return KVM_ARM_TARGET_XGENE_POTENZA in kvm_target_cpu()
when running on X-Gene host with Potenza core.

[maz: sanitized the commit log]

Signed-off-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-12-28 10:28:50 +00:00
Anup Patel
473bdc0e65 ARM64: KVM: Implement kvm_vcpu_preferred_target() function
This patch implements kvm_vcpu_preferred_target() function for
KVM ARM64 which will help us implement KVM_ARM_PREFERRED_TARGET
ioctl for user space.

Signed-off-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2013-10-02 11:29:40 -07:00
Marc Zyngier
0d854a60b1 arm64: KVM: enable initialization of a 32bit vcpu
Wire the init of a 32bit vcpu by allowing 32bit modes in pstate,
and providing sensible defaults out of reset state.

This feature is of course conditioned by the presence of 32bit
capability on the physical CPU, and is checked by the KVM_CAP_ARM_EL1_32BIT
capability.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-06-12 16:42:18 +01:00
Marc Zyngier
2f4a07c5f9 arm64: KVM: guest one-reg interface
Let userspace play with the guest registers.

Reviewed-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-06-07 14:03:39 +01:00