Commit Graph

662399 Commits

Author SHA1 Message Date
Christoffer Dall
a2b19e6e2d KVM: arm/arm64: vgic-its: Cleanup after failed ITT restore
When failing to restore the ITT for a DTE, we should remove the failed
device entry from the list and free the object.

We slightly refactor vgic_its_destroy to be able to reuse the now
separate vgic_its_free_dte() function.

Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09 12:19:46 +02:00
Christoffer Dall
67723c25ce KVM: arm/arm64: Don't call map_resources when restoring ITS tables
The only reason we called kvm_vgic_map_resources() when restoring the
ITS tables was because we wanted to have the KVM iodevs registered in
the KVM IO bus framework at the time when the ITS was restored such that
a restored and active device can inject MSIs prior to otherwise calling
kvm_vgic_map_resources() from the first run of a VCPU.

Since we now register the KVM iodevs for the redestributors and ITS as
soon as possible (when setting the base addresses), we no longer need
this call and kvm_vgic_map_resources() is again called only when first
running a VCPU.

Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09 12:19:46 +02:00
Christoffer Dall
30e1b684f0 KVM: arm/arm64: Register ITS iodev when setting base address
We have to register the ITS iodevice before running the VM, because in
migration scenarios, we may be restoring a live device that wishes to
inject MSIs before the VCPUs have started.

All we need to register the ITS io device is the base address of the
ITS, so we can simply register that when the base address of the ITS is
set.

  [ Code to fix concurrency issues when setting the ITS base address and
    to fix the undef base address check written by Marc Zyngier ]

Signed-off-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09 12:19:42 +02:00
Marc Zyngier
6cc40f273b KVM: arm/arm64: Get rid of its->initialized field
The its->initialized doesn't bring much to the table, and creates
unnecessary ordering between setting the address and initializing it
(which amounts to exactly nothing).

Let's kill it altogether, making KVM_DEV_ARM_VGIC_CTRL_INIT the no-op
it deserves to be.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09 12:19:37 +02:00
Christoffer Dall
1aab6f468c KVM: arm/arm64: Register iodevs when setting redist base and creating VCPUs
Instead of waiting with registering KVM iodevs until the first VCPU is
run, we can actually create the iodevs when the redist base address is
set.  The only downside is that we must now also check if we need to do
this for VCPUs which are created after creating the VGIC, because there
is no enforced ordering between creating the VGIC (and setting its base
addresses) and creating the VCPUs.

Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09 12:19:36 +02:00
Christoffer Dall
72030536eb KVM: arm/arm64: Slightly rework kvm_vgic_addr
As we are about to handle setting the address for the redistributor base
region separately from some of the other base addresses, let's rework
this function to leave a little more room for being flexible in what
each type of base address does.

Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09 12:19:36 +02:00
Christoffer Dall
9a746d75c0 KVM: arm/arm64: Make vgic_v3_check_base more broadly usable
As we are about to fiddle with the IO device registration mechanism,
let's be a little more careful when setting base addresses as early as
possible.  When setting a base address, we can check that there's
address space enough for its scope and when the last of the two
base addresses (dist and redist) get set, we can also check if the
regions overlap at that time.

This allows us to provide error messages to the user at time when trying
to set the base address, as opposed to later when trying to run the VM.

To do this,  we make vgic_v3_check_base available in the core vgic-v3
code as well as in the other parts of the GICv3 code, namely the MMIO
config code.

We also return true for undefined base addresses so that the function
can be used before all base addresses are set; all callers already check
for uninitialized addresses before calling this function.

Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09 12:19:31 +02:00
Christoffer Dall
7fadcd3a85 KVM: arm/arm64: Refactor vgic_register_redist_iodevs
Split out the function to register all the redistributor iodevs into a
function that handles a single redistributor at a time in preparation
for being able to call this per VCPU as these get created.

Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09 12:19:28 +02:00
Christoffer Dall
497d72d80a KVM: Add kvm_vcpu_get_idx to get vcpu index in kvm->vcpus
There are occasional needs to use the index of vcpu in the kvm->vcpus
array to map something related to a VCPU.  For example, unlike the
vcpu->vcpu_id, the vcpu index is guaranteed to not be sparse across all
vcpus which is useful when allocating a memory area for each vcpu.

Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09 12:19:14 +02:00
Christoffer Dall
443c3a9e68 KVM: arm/arm64: vgic: Rename kvm_vgic_vcpu_init to kvm_vgic_vcpu_enable
This function really doesn't init anything, it enables the CPU
interface, so name it as such, which gives us the name to use for actual
init work later on.

Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09 10:51:41 +02:00
Christoffer Dall
cb9d043469 KVM: arm/arm64: Clarification and relaxation to ITS save/restore ABI
Clarify what is meant by the save/restore ABI only supporting virtual
physical interrupts.

Relax the requirement of the order that the collection entries are
written in and be clear that there is no particular ordering enforced.

Some cosmetic changes in the capitalization of ID names to align with
the GICv3 manual and remove the empty line in the bottom of the patch.

Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09 10:51:37 +02:00
Eric Auger
280771252c KVM: arm64: vgic-v3: KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES
This patch adds a new attribute to GICV3 KVM device
KVM_DEV_ARM_VGIC_GRP_CTRL group. This allows userspace to
flush all GICR pending tables into guest RAM.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-08 14:39:31 +02:00
Eric Auger
ccb1d791ab KVM: arm64: vgic-its: Fix pending table sync
In its_sync_lpi_pending_table() we currently ignore the
target_vcpu of the LPIs. We sync the pending bit found in
the vcpu pending table even if the LPI is not targeting it.

Also in vgic_its_cmd_handle_invall() we are supposed to
read the config table data for the LPIs associated to the
collection ID. At the moment we refresh all LPI config
information.

This patch passes a vpcu to vgic_copy_lpi_list() so that
this latter returns a snapshot of the LPIs targeting this
CPU and only those.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-08 14:39:21 +02:00
Eric Auger
eff484e029 KVM: arm64: vgic-its: ITT save and restore
Implement routines to save and restore device ITT and their
interrupt table entries (ITE).

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
2017-05-08 14:39:04 +02:00
Eric Auger
57a9a11715 KVM: arm64: vgic-its: Device table save/restore
This patch saves the device table entries into guest RAM.
Both flat table and 2 stage tables are supported. DeviceId
indexing is used.

For each device listed in the device table, we also save
the translation table using the vgic_its_save/restore_itt
routines. Those functions will be implemented in a subsequent
patch.

On restore, devices are re-allocated and their itt are
re-built.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
2017-05-08 14:38:45 +02:00
Eric Auger
dceff70258 KVM: arm64: vgic-its: vgic_its_check_id returns the entry's GPA
As vgic_its_check_id() computes the device/collection entry's
GPA, let's return it so that new callers can retrieve it easily.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Christoffer Dall <cdall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-08 14:38:34 +02:00
Eric Auger
ea1ad53e1e KVM: arm64: vgic-its: Collection table save/restore
The save path copies the collection entries into guest RAM
at the GPA specified in the BASER register. This obviously
requires the BASER to be set. The last written element is a
dummy collection table entry.

We do not index by collection ID as the collection entry
can fit into 8 bytes while containing the collection ID.

On restore path we re-allocate the collection objects.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-08 14:38:23 +02:00
Eric Auger
920a7a8fa9 KVM: arm64: vgic-its: Add infrastructure for table lookup
Add a generic scan_its_table() helper whose role consists in
scanning a contiguous table located in guest RAM and applying
a callback on each entry. Entries can be handled as linked lists
since the callback may return an id offset to the next entry and
also indicate whether the entry is the last one.

Helper functions also are added to compute the device/event ID
offset to the next DTE/ITE.

compute_next_devid_offset, compute_next_eventid_offset and
scan_table will become static in subsequent patches

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-08 14:38:10 +02:00
Eric Auger
528297f560 KVM: arm64: vgic-its: vgic_its_alloc_ite/device
Add two new helpers to allocate an its ite and an its device.
This will avoid duplication on restore path.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-08 14:37:52 +02:00
Eric Auger
3b65808f4b KVM: arm64: vgic-its: KVM_DEV_ARM_ITS_SAVE/RESTORE_TABLES
Introduce new attributes in KVM_DEV_ARM_VGIC_GRP_CTRL group:
- KVM_DEV_ARM_ITS_SAVE_TABLES: saves the ITS tables into guest RAM
- KVM_DEV_ARM_ITS_RESTORE_TABLES: restores them into VGIC internal
  structures.

We hold the vcpus lock during the save and restore to make
sure no vcpu is running.

At this stage the functionality is not yet implemented. Only
the skeleton is put in place.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
[Given we will move the iodev register until setting the base addr]
Reviewed-by: Christoffer Dall <cdall@linaro.org>
2017-05-08 14:36:37 +02:00
Eric Auger
06bd535954 KVM: arm64: vgic-its: Read config and pending bit in add_lpi()
When creating the lpi we now ask the redistributor what is the state
of the LPI (priority, enabled, pending).

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
2017-05-08 14:36:17 +02:00
Eric Auger
44de9d6838 KVM: arm64: vgic-v3: vgic_v3_lpi_sync_pending_status
this new helper synchronizes the irq pending_latch
with the LPI pending bit status found in rdist pending table.
As the status is consumed, we reset the bit in pending table.

As we need the PENDBASER_ADDRESS() in vgic-v3, let's move its
definition in the irqchip header. We restore the full length
of the field, ie [51:16]. Same for PROPBASER_ADDRESS with full
field length of [51:12].

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
2017-05-08 14:35:59 +02:00
Eric Auger
07a3e9a7b8 KVM: arm64: vgic-its: Check the device id matches TYPER DEVBITS range
On MAPD we currently check the device id can be stored in the device table.
Let's first check it can be encoded within the range defined by TYPER
DEVBITS.

Also check the collection ID belongs to the 16 bit range as GITS_TYPER
CIL field equals to 0.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-08 14:35:42 +02:00
Eric Auger
7333cefe7b KVM: arm64: vgic-its: Interpret MAPD ITT_addr field
Up to now the MAPD ITT_addr had been ignored. We will need it
for save/restore. Let's record it in the its_device struct.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-08 14:35:38 +02:00
Eric Auger
0d44cdb631 KVM: arm64: vgic-its: Interpret MAPD Size field and check related errors
Up to now the MAPD's ITT size field has been ignored. It encodes
the number of eventid bit minus 1. It should be used to check
the eventid when a MAPTI command is issued on a device. Let's
store the number of eventid bits in the its_device and do the
check on MAPTI. Also make sure the ITT size field does
not exceed the GITS_TYPER IDBITS field.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-08 14:35:30 +02:00
Eric Auger
ab01c6bdac KVM: arm64: vgic-its: Implement vgic_mmio_uaccess_write_its_iidr
The GITS_IIDR revision field is used to encode the migration ABI
revision. So we need to restore it to check the table layout is
readable by the destination.

By writing the IIDR, userspace thus forces the ABI revision to be
used and this must be less than or equal to the max revision KVM
supports.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
2017-05-08 14:35:16 +02:00
Eric Auger
71afe470e2 KVM: arm64: vgic-its: Introduce migration ABI infrastructure
We plan to support different migration ABIs, ie. characterizing
the ITS table layout format in guest RAM. For example, a new ABI
will be needed if vLPIs get supported for nested use case.

So let's introduce an array of supported ABIs (at the moment a single
ABI is supported though). The following characteristics are foreseen
to vary with the ABI: size of table entries, save/restore operation,
the way abi settings are applied.

By default the MAX_ABI_REV is applied on its creation. In subsequent
patches we will introduce a way for the userspace to change the ABI
in use.

The entry sizes now are set according to the ABI version and not
hardcoded anymore.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
2017-05-08 14:35:04 +02:00
Eric Auger
0979bfa694 KVM: arm64: vgic-its: Implement vgic_mmio_uaccess_write_its_creadr
GITS_CREADR needs to be restored so let's implement the associated
uaccess_write_its callback. The write only is allowed if the its
is disabled.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
2017-05-08 14:34:50 +02:00
Eric Auger
8331c23c28 KVM: arm64: vgic-its: Implement vgic_its_has_attr_regs and attr_regs_access
This patch implements vgic_its_has_attr_regs and vgic_its_attr_regs_access
upon the MMIO framework. VGIC ITS KVM device KVM_DEV_ARM_VGIC_GRP_ITS_REGS
group becomes functional.

At least GITS_CREADR and GITS_IIDR require to differentiate a guest write
action from a user access. As such let's introduce a new uaccess_its_write
vgic_register_region callback.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-08 14:33:54 +02:00
Eric Auger
dfc99f85c0 KVM: arm/arm64: vgic: expose (un)lock_all_vcpus
We need to use those helpers in vgic-its.c so let's
expose them in the private vgic header.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <cdall@linaro.org>
2017-05-08 14:33:17 +02:00
Eric Auger
876ae234cb KVM: arm64: vgic-its: KVM_DEV_ARM_VGIC_GRP_ITS_REGS group
The ITS KVM device exposes a new KVM_DEV_ARM_VGIC_GRP_ITS_REGS
group which allows the userspace to save/restore ITS registers.

At this stage the get/set/has operations are not yet implemented.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-08 14:33:08 +02:00
Eric Auger
4b7171ac56 arm/arm64: vgic: turn vgic_find_mmio_region into public
We plan to use vgic_find_mmio_region in vgic-its.c so let's
turn it into a public function.

Also let's take the opportunity to rename the region parameter
into regions to emphasize this latter is an array of regions.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <cdall@linaro.org>
2017-05-08 14:31:48 +02:00
Eric Auger
9ce91c7234 KVM: arm/arm64: vgic-its: rename itte into ite
The actual abbreviation for the interrupt translation table entry
is ITE. Let's rename all itte instances by ite.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <cdall@linaro.org>
2017-05-08 14:31:42 +02:00
Eric Auger
100e62983e KVM: arm/arm64: Add GICV3 pending table save API documentation
Add description for how to save GICV3 LPI pending bit into
guest RAM pending tables.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Christoffer Dall <cdall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-08 14:31:22 +02:00
Eric Auger
de2a091079 KVM: arm/arm64: Add ITS save/restore API documentation
Add description for how to access ITS registers and how to save/restore
ITS tables into/from memory.

Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Eric Auger <eric.auger@redhat.com>
2017-05-08 14:30:49 +02:00
Christoffer Dall
35d2d5d490 KVM: arm/arm64: Move shared files to virt/kvm/arm
For some time now we have been having a lot of shared functionality
between the arm and arm64 KVM support in arch/arm, which not only
required a horrible inter-arch reference from the Makefile in
arch/arm64/kvm, but also created confusion for newcomers to the code
base, as was recently seen on the mailing list.

Further, it causes confusion for things like cscope, which needs special
attention to index specific shared files for arm64 from the arm tree.

Move the shared files into virt/kvm/arm and move the trace points along
with it.  When moving the tracepoints we have to modify the way the vgic
creates definitions of the trace points, so we take the chance to
include the VGIC tracepoints in its very own special vgic trace.h file.

Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-05-04 13:57:26 +02:00
Marc Zyngier
c667186f1c arm64: KVM: Fix decoding of Rt/Rt2 when trapping AArch32 CP accesses
Our 32bit CP14/15 handling inherited some of the ARMv7 code for handling
the trapped system registers, completely missing the fact that the
fields for Rt and Rt2 are now 5 bit wide, and not 4...

Let's fix it, and provide an accessor for the most common Rt case.

Cc: stable@vger.kernel.org
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-05-02 09:53:46 +02:00
Marc Zyngier
1edb632133 ARM: KVM: Fix idmap stub entry when running Thumb-2 code
When entering the hyp stub implemented in the idmap, we try to
be mindful of the fact that we could be running a Thumb-2 kernel
by adding 1 to the address we compute. Unfortunately, the assembler
also knows about this trick, and has already generated an address
that has bit 0 set in the litteral pool.

Our superfluous correction ends up confusing the CPU entierely,
as we now branch to the stub in ARM mode instead of Thumb, and on
a possibly unaligned address for good measure. From that point,
nothing really good happens.

The obvious fix in to remove this stupid target PC correction.

Fixes: 6bebcecb6c ("ARM: KVM: Allow the main HYP code to use the init hyp stub implementation")
Reported-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-04-20 20:17:57 +02:00
Marc Zyngier
5b560525ad ARM: hyp-stub: Fix Thumb-2 compilation
The assembler defaults to emiting the short form of ADR, leading
to an out-of-range immediate. Using the wide version solves this
issue.

Fixes: bc845e4fbb ("ARM: KVM: Implement HVC_RESET_VECTORS stub hypercall in the init code")
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-04-20 12:58:53 +02:00
Marc Zyngier
cffcd9df10 KVM: arm/arm64: vgic-v3: Fix off-by-one LR access
When iterating over the used LRs, be careful not to try to access
an unused LR, or even an unimplemented one if you're unlucky...

Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-04-19 17:28:38 +02:00
Marc Zyngier
ff567614d5 KVM: arm/arm64: vgic-v3: De-optimize VMCR save/restore when emulating a GICv2
When emulating a GICv2-on-GICv3, special care must be taken to only
save/restore VMCR_EL2 when ICC_SRE_EL1.SRE is cleared. Otherwise,
all Group-0 interrupts end-up being delivered as FIQ, which is
probably not what the guest expects, as demonstrated here with
an unhappy EFI:

	FIQ Exception at 0x000000013BD21CC4

This means that we cannot perform the load/put trick when dealing
with VMCR_EL2 (because the host has SRE set), and we have to deal
with it in the world-switch.

Fortunately, this is not the most common case (modern guests should
be able to deal with GICv3 directly), and the performance is not worse
than what it was before the VMCR optimization.

Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-04-19 17:28:38 +02:00
Andrew Jones
6c7a5dce22 KVM: arm/arm64: fix races in kvm_psci_vcpu_on
Fix potential races in kvm_psci_vcpu_on() by taking the kvm->lock
mutex.  In general, it's a bad idea to allow more than one PSCI_CPU_ON
to process the same target VCPU at the same time.  One such problem
that may arise is that one PSCI_CPU_ON could be resetting the target
vcpu, which fills the entire sys_regs array with a temporary value
including the MPIDR register, while another looks up the VCPU based
on the MPIDR value, resulting in no target VCPU found.  Resolves both
races found with the kvm-unit-tests/arm/psci unit test.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Reported-by: Levente Kurusa <lkurusa@redhat.com>
Suggested-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Andrew Jones <drjones@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-04-19 17:28:11 +02:00
Christoffer Dall
5f6e00709c Merge remote-tracking branch 'rutland/kvm/common-sysreg' into next-fix 2017-04-09 07:50:34 -07:00
Christoffer Dall
f7214e6023 KVM: arm/arm64: Advertise support for KVM_CAP_ARM_USER_IRQ
Now that we support both timers and PMU reporting interrupts
to userspace, we can advertise this support.

Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-04-09 07:49:40 -07:00
Christoffer Dall
3dbbdf7863 KVM: arm/arm64: Report PMU overflow interrupts to userspace irqchip
When not using an in-kernel VGIC, but instead emulating an interrupt
controller in userspace, we should report the PMU overflow status to
that userspace interrupt controller using the KVM_CAP_ARM_USER_IRQ
feature.

Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-04-09 07:49:39 -07:00
Alexander Graf
d9e1397783 KVM: arm/arm64: Support arch timers with a userspace gic
If you're running with a userspace gic or other interrupt controller
(that is no vgic in the kernel), then you have so far not been able to
use the architected timers, because the output of the architected
timers, which are driven inside the kernel, was a kernel-only construct
between the arch timer code and the vgic.

This patch implements the new KVM_CAP_ARM_USER_IRQ feature, where we use a
side channel on the kvm_run structure, run->s.regs.device_irq_level, to
always notify userspace of the timer output levels when using a userspace
irqchip.

This works by ensuring that before we enter the guest, if the timer
output level has changed compared to what we last told userspace, we
don't enter the guest, but instead return to userspace to notify it of
the new level.  If we are exiting, because of an MMIO for example, and
the level changed at the same time, the value is also updated and
userspace can sample the line as it needs.  This is nicely achieved
simply always updating the timer_irq_level field after the main run
loop.

Note that the kvm_timer_update_irq trace event is changed to show the
host IRQ number for the timer instead of the guest IRQ number, because
the kernel no longer know which IRQ userspace wires up the timer signal
to.

Also note that this patch implements all required functionality but does
not yet advertise the capability.

Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-04-09 07:49:38 -07:00
Alexander Graf
3fe17e6826 KVM: arm/arm64: Add ARM user space interrupt signaling ABI
We have 2 modes for dealing with interrupts in the ARM world. We can
either handle them all using hardware acceleration through the vgic or
we can emulate a gic in user space and only drive CPU IRQ pins from
there.

Unfortunately, when driving IRQs from user space, we never tell user
space about events from devices emulated inside the kernel, which may
result in interrupt line state changes, so we lose out on for example
timer and PMU events if we run with user space gic emulation.

Define an ABI to publish such device output levels to userspace.

Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-09 07:49:38 -07:00
Christoffer Dall
b22e7df2d8 KVM: arm/arm64: Cleanup the arch timer code's irqchip checking
Currently we check if we have an in-kernel irqchip and if the vgic was
properly implemented several places in the arch timer code.  But, we
already predicate our enablement of the arm timers on having a valid
and initialized gic, so we can simply check if the timers are enabled or
not.

This also gets rid of the ugly "error that's not an error but used to
signal that the timer shouldn't poke the gic" construct we have.

Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-04-09 07:49:37 -07:00
Marc Zyngier
d824ca52ab arm/arm64: Add hyp-stub API documentation
In order to help people understanding the hyp-stub API that exists
between the host kernel and the hypervisor mode (whether a hypervisor
has been installed or not), let's document said API.

As with any form of documentation, I expect it to become obsolete
and completely misleading within 20 minutes after having being merged.

Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-04-09 07:49:36 -07:00
Marc Zyngier
d9118c87d2 ARM: hyp-stub: Zero r0 on successful stub handling
We now return HVC_STUB_ERR when a stub hypercall fails, but we
leave whatever was in r0 on success. Zeroing it on return seems
like a good idea.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-04-09 07:49:36 -07:00