Commit Graph

232 Commits

Author SHA1 Message Date
Paolo Bonzini
a788260b20 kvm: require KVM_IRQFD for kernel irqchip
KVM_IRQFD was introduced in Linux 2.6.32, and since then it has always been
available on architectures that support an in-kernel interrupt controller.
We can require it unconditionally.

Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-10-25 17:35:15 +02:00
Paolo Bonzini
cc5e719e2c kvm: require KVM_CAP_SIGNAL_MSI
This was introduced in KVM in Linux 3.5, we can require it unconditionally
in kvm_irqchip_send_msi().  However, not all architectures have to implement
it so check it only in x86, the only architecture that ever had MSI injection
but not KVM_CAP_SIGNAL_MSI.

ARM uses it to detect the presence of the ITS emulation in the kernel,
introduced in Linux 4.8.  Assume that it's there and possibly fail when
realizing the arm-its-kvm device.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-10-25 17:35:14 +02:00
Paolo Bonzini
aacec9aee1 kvm: require KVM_CAP_INTERNAL_ERROR_DATA
This was introduced in KVM in Linux 2.6.33, we can require it unconditionally.

Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-10-25 17:35:14 +02:00
David Hildenbrand
16ab2eda57 kvm: Add stub for kvm_get_max_memslots()
We'll need the stub soon from memory device context.

While at it, use "unsigned int" as return value and place the
declaration next to kvm_get_free_memslots().

Message-ID: <20230926185738.277351-11-david@redhat.com>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
2023-10-12 14:15:22 +02:00
David Hildenbrand
5b23186a95 kvm: Return number of free memslots
Let's return the number of free slots instead of only checking if there
is a free slot. While at it, check all address spaces, which will also
consider SMM under x86 correctly.

This is a preparation for memory devices that consume multiple memslots.

Message-ID: <20230926185738.277351-5-david@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
2023-10-12 14:15:22 +02:00
Richard Henderson
464dacf609 accel/tcg: Move can_do_io to CPUNegativeOffsetState
Minimize the displacement to can_do_io, since it may
be touched at the start of each TranslationBlock.
It fits into other padding within the substructure.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-03 08:01:02 -07:00
Akihiko Odaki
7191f24c7f accel/kvm/kvm-all: Handle register access errors
A register access error typically means something seriously wrong
happened so that anything bad can happen after that and recovery is
impossible.
Even failing one register access is catastorophic as
architecture-specific code are not written so that it torelates such
failures.

Make sure the VM stop and nothing worse happens if such an error occurs.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-ID: <20221201102728.69751-1-akihiko.odaki@daynix.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-09-29 09:33:10 +02:00
Shameer Kolothum
c8f2eb5d41 arm/kvm: Enable support for KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE
Now that we have Eager Page Split support added for ARM in the kernel,
enable it in Qemu. This adds,
 -eager-split-size to -accel sub-options to set the eager page split chunk size.
 -enable KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE.

The chunk size specifies how many pages to break at a time, using a
single allocation. Bigger the chunk size, more pages need to be
allocated ahead of time.

Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Message-id: 20230905091246.1931-1-shameerali.kolothum.thodi@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-09-08 16:41:36 +01:00
Anton Johansson
b67be03e3a accel/kvm: Widen pc/saved_insn for kvm_sw_breakpoint
Widens the pc and saved_insn fields of kvm_sw_breakpoint from
target_ulong to vaddr. The pc argument of kvm_find_sw_breakpoint is also
widened to match.

Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230807155706.9580-2-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-08-24 11:21:22 -07:00
Akihiko Odaki
43a5e377f4 accel/kvm: Make kvm_dirty_ring_reaper_init() void
The returned value was always zero and had no meaning.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20230727073134.134102-7-akihiko.odaki@daynix.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-08-22 17:31:04 +01:00
Akihiko Odaki
4625742cd2 accel/kvm: Free as when an error occurred
An error may occur after s->as is allocated, for example if the
KVM_CREATE_VM ioctl call fails.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20230727073134.134102-6-akihiko.odaki@daynix.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: tweaked commit message]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-08-22 17:31:04 +01:00
Akihiko Odaki
bc3e41a0e8 accel/kvm: Use negative KVM type for error propagation
On MIPS, kvm_arch_get_default_type() returns a negative value when an
error occurred so handle the case. Also, let other machines return
negative values when errors occur and declare returning a negative
value as the correct way to propagate an error that happened when
determining KVM type.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20230727073134.134102-5-akihiko.odaki@daynix.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-08-22 17:31:03 +01:00
Akihiko Odaki
5e0d65909c kvm: Introduce kvm_arch_get_default_type hook
kvm_arch_get_default_type() returns the default KVM type. This hook is
particularly useful to derive a KVM type that is valid for "none"
machine model, which is used by libvirt to probe the availability of
KVM.

For MIPS, the existing mips_kvm_type() is reused. This function ensures
the availability of VZ which is mandatory to use KVM on the current
QEMU.

Cc: qemu-stable@nongnu.org
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20230727073134.134102-2-akihiko.odaki@daynix.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: added doc comment for new function]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-08-22 17:31:02 +01:00
Gavin Shan
fe6bda58e0 kvm: Fix crash due to access uninitialized kvm_state
Runs into core dump on arm64 and the backtrace extracted from the
core dump is shown as below. It's caused by accessing uninitialized
@kvm_state in kvm_flush_coalesced_mmio_buffer() due to commit 176d073029
("hw/arm/virt: Use machine_memory_devices_init()"), where the machine's
memory region is added earlier than before.

    main
    qemu_init
    configure_accelerators
    qemu_opts_foreach
    do_configure_accelerator
    accel_init_machine
    kvm_init
    virt_kvm_type
    virt_set_memmap
    machine_memory_devices_init
    memory_region_add_subregion
    memory_region_add_subregion_common
    memory_region_update_container_subregions
    memory_region_transaction_begin
    qemu_flush_coalesced_mmio_buffer
    kvm_flush_coalesced_mmio_buffer

Fix it by bailing early in kvm_flush_coalesced_mmio_buffer() on the
uninitialized @kvm_state. With this applied, no crash is observed on
arm64.

Fixes: 176d073029 ("hw/arm/virt: Use machine_memory_devices_init()")
Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20230731125946.2038742-1-gshan@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-07-31 14:19:43 +01:00
Isaku Yamahata
14a868c626 exec/memory: Add symbol for the min value of memory listener priority
Add MEMORY_LISTNER_PRIORITY_MIN for the symbolic value for the min value of
the memory listener instead of the hard-coded magic value 0.  Add explicit
initialization.

No functional change intended.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <29f88477fe82eb774bcfcae7f65ea21995f865f2.1687279702.git.isaku.yamahata@intel.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-06-28 14:27:59 +02:00
Isaku Yamahata
8be0461d37 exec/memory: Add symbol for memory listener priority for device backend
Add MEMORY_LISTENER_PRIORITY_DEV_BACKEND for the symbolic value
for memory listener to replace the hard-coded value 10 for the
device backend.

No functional change intended.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <8314d91688030d7004e96958f12e2c83fb889245.1687279702.git.isaku.yamahata@intel.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-06-28 14:27:59 +02:00
Isaku Yamahata
5369a36c4f exec/memory: Add symbolic value for memory listener priority for accel
Add MEMORY_LISTNER_PRIORITY_ACCEL for the symbolic value for the memory
listener to replace the hard-coded value 10 for accel.

No functional change intended.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <feebe423becc6e2aa375f59f6abce9a85bc15abb.1687279702.git.isaku.yamahata@intel.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-06-28 14:27:59 +02:00
Marcelo Tosatti
3b6f485275 kvm: reuse per-vcpu stats fd to avoid vcpu interruption
A regression has been detected in latency testing of KVM guests.
More specifically, it was observed that the cyclictest
numbers inside of an isolated vcpu (running on isolated pcpu) are:

Where a maximum of 50us is acceptable.

The implementation of KVM_GET_STATS_FD uses run_on_cpu to query
per vcpu statistics, which interrupts the vcpu (and is unnecessary).

To fix this, open the per vcpu stats fd on vcpu initialization,
and read from that fd from QEMU's main thread.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-06-26 10:23:01 +02:00
Gavin Shan
856e23a0fb kvm: Enable dirty ring for arm64
arm64 has different capability from x86 to enable the dirty ring, which
is KVM_CAP_DIRTY_LOG_RING_ACQ_REL. Besides, arm64 also needs the backup
bitmap extension (KVM_CAP_DIRTY_LOG_RING_WITH_BITMAP) when 'kvm-arm-gicv3'
or 'arm-its-kvm' device is enabled. Here the extension is always enabled
and the unnecessary overhead to do the last stage of dirty log synchronization
when those two devices aren't used is introduced, but the overhead should
be very small and acceptable. The benefit is cover future cases where those
two devices are used without modifying the code.

Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Tested-by: Zhenyu Zhang <zhenyzha@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20230509022122.20888-5-gshan@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-05-18 08:53:51 +02:00
Gavin Shan
3794cb9485 kvm: Add helper kvm_dirty_ring_init()
Due to multiple capabilities associated with the dirty ring for different
architectures: KVM_CAP_DIRTY_{LOG_RING, LOG_RING_ACQ_REL} for x86 and
arm64 separately. There will be more to be done in order to support the
dirty ring for arm64.

Lets add helper kvm_dirty_ring_init() to enable the dirty ring. With this,
the code looks a bit clean.

No functional change intended.

Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Zhenyu Zhang <zhenyzha@redhat.com>
Message-Id: <20230509022122.20888-4-gshan@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-05-18 08:53:50 +02:00
Gavin Shan
b20cc77692 kvm: Synchronize the backup bitmap in the last stage
In the last stage of live migration or memory slot removal, the
backup bitmap needs to be synchronized when it has been enabled.

Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Zhenyu Zhang <zhenyzha@redhat.com>
Message-Id: <20230509022122.20888-3-gshan@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-05-18 08:53:50 +02:00
Gavin Shan
1e493be587 migration: Add last stage indicator to global dirty log
The global dirty log synchronization is used when KVM and dirty ring
are enabled. There is a particularity for ARM64 where the backup
bitmap is used to track dirty pages in non-running-vcpu situations.
It means the dirty ring works with the combination of ring buffer
and backup bitmap. The dirty bits in the backup bitmap needs to
collected in the last stage of live migration.

In order to identify the last stage of live migration and pass it
down, an extra parameter is added to the relevant functions and
callbacks. This last stage indicator isn't used until the dirty
ring is enabled in the subsequent patches.

No functional change intended.

Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Zhenyu Zhang <zhenyzha@redhat.com>
Message-Id: <20230509022122.20888-2-gshan@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-05-18 08:53:50 +02:00
Peter Xu
56adee407f kvm: dirty-ring: Fix race with vcpu creation
It's possible that we want to reap a dirty ring on a vcpu that is during
creation, because the vcpu is put onto list (CPU_FOREACH visible) before
initialization of the structures.  In this case:

qemu_init_vcpu
    x86_cpu_realizefn
        cpu_exec_realizefn
            cpu_list_add      <---- can be probed by CPU_FOREACH
        qemu_init_vcpu
            cpus_accel->create_vcpu_thread(cpu);
                kvm_init_vcpu
                    map kvm_dirty_gfns  <--- kvm_dirty_gfns valid

Don't try to reap dirty ring on vcpus during creation or it'll crash.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2124756
Reported-by: Xiaohui Li <xiaohli@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1d14deb6684bcb7de1c9633c5bd21113988cc698.1676563222.git.huangy81@chinatelecom.cn>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-04-04 18:46:46 +02:00
Mads Ynddal
412ae12647 gdbstub: move update guest debug to accel ops
Continuing the refactor of a48e7d9e52 (gdbstub: move guest debug support
check to ops) by removing hardcoded kvm_enabled() from generic cpu.c
code, and replace it with a property of AccelOpsClass.

Signed-off-by: Mads Ynddal <m.ynddal@samsung.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230207131721.49233-1-mads@ynddal.dk>
[AJB: add ifdef around update_guest_debug_ops, fix brace]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230302190846.2593720-27-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-30-richard.henderson@linaro.org>
2023-03-07 20:44:09 +00:00
David Woodhouse
e16aff4cc2 kvm/i386: Add xen-evtchn-max-pirq property
The default number of PIRQs is set to 256 to avoid issues with 32-bit MSI
devices. Allow it to be increased if the user desires.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
2023-03-01 09:09:22 +00:00
David Woodhouse
6f43f2ee49 kvm/i386: Add xen-gnttab-max-frames property
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
2023-03-01 09:07:52 +00:00
David Woodhouse
61491cf441 i386/kvm: Add xen-version KVM accelerator property and init KVM Xen support
This just initializes the basic Xen support in KVM for now. Only permitted
on TYPE_PC_MACHINE because that's where the sysbus devices for Xen heap
overlay, event channel, grant tables and other stuff will exist. There's
no point having the basic hypercall support if nothing else works.

Provide sysemu/kvm_xen.h and a kvm_xen_get_caps() which will be used
later by support devices.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
2023-03-01 08:22:49 +00:00
Philippe Mathieu-Daudé
2459d4209f accel/kvm: Silent -Wmissing-field-initializers warning
Silent when compiling with -Wextra:

  ../accel/kvm/kvm-all.c:2291:17: warning: missing field 'num' initializer [-Wmissing-field-initializers]
        { NULL, }
                ^

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221220143532.24958-3-philmd@linaro.org>
2023-02-27 22:29:01 +01:00
Philippe Mathieu-Daudé
55b5b8e928 gdbstub: Use vaddr type for generic insert/remove_breakpoint() API
Both insert/remove_breakpoint() handlers are used in system and
user emulation. We can not use the 'hwaddr' type on user emulation,
we have to use 'vaddr' which is defined as "wide enough to contain
any #target_ulong virtual address".

gdbstub.c doesn't require to include "exec/hwaddr.h" anymore.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20221216215519.5522-4-philmd@linaro.org>
2023-02-27 22:29:01 +01:00
Markus Armbruster
aa09b3d5f8 stats: Move QMP commands from monitor/ to stats/
This moves these commands from MAINTAINERS section "QMP" to new
section "Stats".  Status is Orphan.  Volunteers welcome!

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-23-armbru@redhat.com>
2023-02-04 07:56:54 +01:00
David Hildenbrand
f39b7d2b96 kvm: Atomic memslot updates
If we update an existing memslot (e.g., resize, split), we temporarily
remove the memslot to re-add it immediately afterwards. These updates
are not atomic, especially not for KVM VCPU threads, such that we can
get spurious faults.

Let's inhibit most KVM ioctls while performing relevant updates, such
that we can perform the update just as if it would happen atomically
without additional kernel support.

We capture the add/del changes and apply them in the notifier commit
stage instead. There, we can check for overlaps and perform the ioctl
inhibiting only if really required (-> overlap).

To keep things simple we don't perform additional checks that wouldn't
actually result in an overlap -- such as !RAM memory regions in some
cases (see kvm_set_phys_mem()).

To minimize cache-line bouncing, use a separate indicator
(in_ioctl_lock) per CPU.  Also, make sure to hold the kvm_slots_lock
while performing both actions (removing+re-adding).

We have to wait until all IOCTLs were exited and block new ones from
getting executed.

This approach cannot result in a deadlock as long as the inhibitor does
not hold any locks that might hinder an IOCTL from getting finished and
exited - something fairly unusual. The inhibitor will always hold the BQL.

AFAIKs, one possible candidate would be userfaultfd. If a page cannot be
placed (e.g., during postcopy), because we're waiting for a lock, or if the
userfaultfd thread cannot process a fault, because it is waiting for a
lock, there could be a deadlock. However, the BQL is not applicable here,
because any other guest memory access while holding the BQL would already
result in a deadlock.

Nothing else in the kernel should block forever and wait for userspace
intervention.

Note: pause_all_vcpus()/resume_all_vcpus() or
start_exclusive()/end_exclusive() cannot be used, as they either drop
the BQL or require to be called without the BQL - something inhibitors
cannot handle. We need a low-level locking mechanism that is
deadlock-free even when not releasing the BQL.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Tested-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20221111154758.1372674-4-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-01-11 09:59:39 +01:00
Emanuele Giuseppe Esposito
a27dd2de68 KVM: keep track of running ioctls
Using the new accel-blocker API, mark where ioctls are being called
in KVM. Next, we will implement the critical section that will take
care of performing memslots modifications atomically, therefore
preventing any new ioctl from running and allowing the running ones
to finish.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20221111154758.1372674-3-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-01-11 09:59:39 +01:00
Markus Armbruster
d1c81c3496 qapi: Use returned bool to check for failure (again)
Commit 012d4c96e2 changed the visitor functions taking Error ** to
return bool instead of void, and the commits following it used the new
return value to simplify error checking.  Since then a few more uses
in need of the same treatment crept in.  Do that.  All pretty
mechanical except for

* balloon_stats_get_all()

  This is basically the same transformation commit 012d4c96e2 applied
  to the virtual walk example in include/qapi/visitor.h.

* set_max_queue_size()

  Additionally replace "goto end of function" by return.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221121085054.683122-10-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2022-12-14 16:19:35 +01:00
Chenyi Qiang
e2e69f6bb9 i386: add notify VM exit support
There are cases that malicious virtual machine can cause CPU stuck (due
to event windows don't open up), e.g., infinite loop in microcode when
nested #AC (CVE-2015-5307). No event window means no event (NMI, SMI and
IRQ) can be delivered. It leads the CPU to be unavailable to host or
other VMs. Notify VM exit is introduced to mitigate such kind of
attacks, which will generate a VM exit if no event window occurs in VM
non-root mode for a specified amount of time (notify window).

A new KVM capability KVM_CAP_X86_NOTIFY_VMEXIT is exposed to user space
so that the user can query the capability and set the expected notify
window when creating VMs. The format of the argument when enabling this
capability is as follows:
  Bit 63:32 - notify window specified in qemu command
  Bit 31:0  - some flags (e.g. KVM_X86_NOTIFY_VMEXIT_ENABLED is set to
              enable the feature.)

Users can configure the feature by a new (x86 only) accel property:
    qemu -accel kvm,notify-vmexit=run|internal-error|disable,notify-window=n

The default option of notify-vmexit is run, which will enable the
capability and do nothing if the exit happens. The internal-error option
raises a KVM internal error if it happens. The disable option does not
enable the capability. The default value of notify-window is 0. It is valid
only when notify-vmexit is not disabled. The valid range of notify-window
is non-negative. It is even safe to set it to zero since there's an
internal hardware threshold to be added to ensure no false positive.

Because a notify VM exit may happen with VM_CONTEXT_INVALID set in exit
qualification (no cases are anticipated that would set this bit), which
means VM context is corrupted. It would be reflected in the flags of
KVM_EXIT_NOTIFY exit. If KVM_NOTIFY_CONTEXT_INVALID bit is set, raise a KVM
internal error unconditionally.

Acked-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
Message-Id: <20220929072014.20705-5-chenyi.qiang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-10-11 09:36:00 +02:00
Chenyi Qiang
5f8a6bce1f kvm: expose struct KVMState
Expose struct KVMState out of kvm-all.c so that the field of struct
KVMState can be accessed when defining target-specific accelerator
properties.

Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
Message-Id: <20220929072014.20705-4-chenyi.qiang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-10-11 09:36:00 +02:00
Paolo Bonzini
3dba0a335c kvm: allow target-specific accelerator properties
Several hypervisor capabilities in KVM are target-specific.  When exposed
to QEMU users as accelerator properties (i.e. -accel kvm,prop=value), they
should not be available for all targets.

Add a hook for targets to add their own properties to -accel kvm, for
now no such property is defined.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220929072014.20705-3-chenyi.qiang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-10-10 09:23:16 +02:00
Alex Bennée
c7f1c53735 accel/kvm: move kvm_update_guest_debug to inline stub
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220929114231.583801-47-alex.bennee@linaro.org>
2022-10-06 11:53:41 +01:00
Alex Bennée
a48e7d9e52 gdbstub: move guest debug support check to ops
This removes the final hard coding of kvm_enabled() in gdbstub and
moves the check to an AccelOps.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Mads Ynddal <mads@ynddal.dk>
Message-Id: <20220929114231.583801-46-alex.bennee@linaro.org>
2022-10-06 11:53:41 +01:00
Alex Bennée
ae7467b1ac gdbstub: move breakpoint logic to accel ops
As HW virtualization requires specific support to handle breakpoints
lets push out special casing out of the core gdbstub code and into
AccelOpsClass. This will make it easier to add other accelerator
support and reduces some of the stub shenanigans.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Mads Ynddal <mads@ynddal.dk>
Message-Id: <20220929114231.583801-45-alex.bennee@linaro.org>
2022-10-06 11:53:41 +01:00
Alex Bennée
3b7a93880a gdbstub: move sstep flags probing into AccelClass
The support of single-stepping is very much dependent on support from
the accelerator we are using. To avoid special casing in gdbstub move
the probing out to an AccelClass function so future accelerators can
put their code there.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Mads Ynddal <mads@ynddal.dk>
Message-Id: <20220929114231.583801-44-alex.bennee@linaro.org>
2022-10-06 11:53:41 +01:00
Paolo Bonzini
21adec30f6 kvm: fix memory leak on failure to read stats descriptors
Reported by Coverity as CID 1490142.  Since the size is constant and the
lifetime is the same as the StatsDescriptors struct, embed the struct
directly instead of using a separate allocation.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-18 09:17:40 +02:00
Paolo Bonzini
52281c6d11 KVM: use store-release to mark dirty pages as harvested
The following scenario can happen if QEMU sets more RESET flags while
the KVM_RESET_DIRTY_RINGS ioctl is ongoing on another host CPU:

    CPU0                     CPU1               CPU2
    ------------------------ ------------------ ------------------------
                                                fill gfn0
                                                store-rel flags for gfn0
                                                fill gfn1
                                                store-rel flags for gfn1
    load-acq flags for gfn0
    set RESET for gfn0
    load-acq flags for gfn1
    set RESET for gfn1
    do ioctl! ----------->
                             ioctl(RESET_RINGS)
                                                fill gfn2
                                                store-rel flags for gfn2
    load-acq flags for gfn2
    set RESET for gfn2
                             process gfn0
                             process gfn1
                             process gfn2
    do ioctl!
    etc.

The three load-acquire in CPU0 synchronize with the three store-release
in CPU2, but CPU0 and CPU1 are only synchronized up to gfn1 and CPU1
may miss gfn2's fields other than flags.

The kernel must be able to cope with invalid values of the fields, and
userspace *will* invoke the ioctl once more.  However, once the RESET flag
is cleared on gfn2, it is lost forever, therefore in the above scenario
CPU1 must read the correct value of gfn2's fields.

Therefore RESET must be set with a store-release, that will synchronize
with KVM's load-acquire in CPU1.

Cc: Gavin Shan <gshan@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-18 09:17:40 +02:00
Paolo Bonzini
4802bf910e KVM: dirty ring: add missing memory barrier
The KVM_DIRTY_GFN_F_DIRTY flag ensures that the entry is valid.  If
the read of the fields are not ordered after the read of the flag,
QEMU might see stale values.

Cc: Gavin Shan <gshan@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-01 08:37:04 +02:00
Paolo Bonzini
a9197ad210 kvm: fix segfault with query-stats-schemas and -M none
-M none creates a guest without a vCPU, causing the following error:

$ ./qemu-system-x86_64 -qmp stdio -M none -accel kvm
{execute:qmp_capabilities}
{"return": {}}
{execute: query-stats-schemas}
Segmentation fault (core dumped)

Fix it by not querying the vCPU stats if first_cpu is NULL.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-08-18 14:08:24 +02:00
Cornelia Huck
47c182fe8b kvm: don't use perror() without useful errno
perror() is designed to append the decoded errno value to a
string. This, however, only makes sense if we called something that
actually sets errno prior to that.

For the callers that check for split irqchip support that is not the
case, and we end up with confusing error messages that end in
"success". Use error_report() instead.

Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20220728142446.438177-1-cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-07-29 00:15:02 +02:00
Peter Maydell
d12dd9c7ee accel/kvm: Avoid Coverity warning in query_stats()
Coverity complains that there is a codepath in the query_stats()
function where it can leak the memory pointed to by stats_list.  This
can only happen if the caller passes something other than
STATS_TARGET_VM or STATS_TARGET_VCPU as the 'target', which no
callsite does.  Enforce this assumption using g_assert_not_reached(),
so that if we have a future bug we hit the assert rather than
silently leaking memory.

Resolves: Coverity CID 1490140
Fixes: cc01a3f4ca ("kvm: Support for querying fd-based stats")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20220719134853.327059-1-peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-07-22 19:01:44 +02:00
Peter Maydell
5288bee45f * Boolean statistics for KVM
* Fix build on Haiku
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Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into staging

* Boolean statistics for KVM
* Fix build on Haiku

# gpg: Signature made Tue 19 Jul 2022 10:32:34 BST
# gpg:                using RSA key F13338574B662389866C7682BFFBD25F78C7AE83
# gpg:                issuer "pbonzini@redhat.com"
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [full]
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>" [full]
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* tag 'for-upstream' of https://gitlab.com/bonzini/qemu:
  util: Fix broken build on Haiku
  kvm: add support for boolean statistics
  monitor: add support for boolean statistics

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-07-21 11:13:01 +01:00
Hyman Huang(黄勇)
baa609832e softmmu/dirtylimit: Implement virtual CPU throttle
Setup a negative feedback system when vCPU thread
handling KVM_EXIT_DIRTY_RING_FULL exit by introducing
throttle_us_per_full field in struct CPUState. Sleep
throttle_us_per_full microseconds to throttle vCPU
if dirtylimit is in service.

Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <977e808e03a1cef5151cae75984658b6821be618.1656177590.git.huangy81@chinatelecom.cn>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20 12:15:08 +01:00
Hyman Huang(黄勇)
4a06a7cc05 accel/kvm/kvm-all: Introduce kvm_dirty_ring_size function
Introduce kvm_dirty_ring_size util function to help calculate
dirty ring ful time.

Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
Acked-by: Peter Xu <peterx@redhat.com>
Message-Id: <f9ce1f550bfc0e3a1f711e17b1dbc8f701700e56.1656177590.git.huangy81@chinatelecom.cn>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20 12:15:08 +01:00
Hyman Huang(黄勇)
1667e2b97b accel/kvm/kvm-all: Refactor per-vcpu dirty ring reaping
Add a non-required argument 'CPUState' to kvm_dirty_ring_reap so
that it can cover single vcpu dirty-ring-reaping scenario.

Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <c32001242875e83b0d9f78f396fe2dcd380ba9e8.1656177590.git.huangy81@chinatelecom.cn>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20 12:15:08 +01:00
Paolo Bonzini
105bb7cdbe kvm: add support for boolean statistics
The next version of Linux will introduce boolean statistics, which
can only have 0 or 1 values.  Convert them to the new QAPI fields
added in the previous commit.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-07-18 18:51:32 +02:00
Miaoqian Lin
f696b74b15 accel: kvm: Fix memory leak in find_stats_descriptors
This function doesn't release descriptors in one error path,
result in memory leak. Call g_free() to release it.

Fixes: cc01a3f4ca ("kvm: Support for querying fd-based stats")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Message-Id: <20220624063159.57411-1-linmq006@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-07-08 11:03:36 +02:00
Paolo Bonzini
cf7405bc02 qmp: add filtering of statistics by name
Allow retrieving only a subset of statistics.  This can be useful
for example in order to plot a subset of the statistics many times
a second: KVM publishes ~40 statistics for each vCPU on x86; retrieving
and serializing all of them would be useless.

Another use will be in HMP in the following patch; implementing the
filter in the backend is easy enough that it was deemed okay to make
this a public interface.

Example:

{ "execute": "query-stats",
  "arguments": {
    "target": "vcpu",
    "vcpus": [ "/machine/unattached/device[2]",
               "/machine/unattached/device[4]" ],
    "providers": [
      { "provider": "kvm",
        "names": [ "l1d_flush", "exits" ] } } }

{ "return": {
    "vcpus": [
      { "path": "/machine/unattached/device[2]"
        "providers": [
          { "provider": "kvm",
            "stats": [ { "name": "l1d_flush", "value": 41213 },
                       { "name": "exits", "value": 74291 } ] } ] },
      { "path": "/machine/unattached/device[4]"
        "providers": [
          { "provider": "kvm",
            "stats": [ { "name": "l1d_flush", "value": 16132 },
                       { "name": "exits", "value": 57922 } ] } ] } ] } }

Extracted from a patch by Mark Kanda.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-14 16:50:30 +02:00
Paolo Bonzini
068cc51d42 qmp: add filtering of statistics by provider
Allow retrieving the statistics from a specific provider only.
This can be used in the future by HMP commands such as "info
sync-profile" or "info profile".  The next patch also adds
filter-by-provider capabilities to the HMP equivalent of
query-stats, "info stats".

Example:

{ "execute": "query-stats",
  "arguments": {
    "target": "vm",
    "providers": [
      { "provider": "kvm" } ] } }

The QAPI is a bit more verbose than just a list of StatsProvider,
so that it can be subsequently extended with filtering of statistics
by name.

If a provider is specified more than once in the filter, each request
will be included separately in the output.

Extracted from a patch by Mark Kanda.

Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-14 16:50:30 +02:00
Paolo Bonzini
467ef823d8 qmp: add filtering of statistics by target vCPU
Introduce a simple filtering of statistics, that allows to retrieve
statistics for a subset of the guest vCPUs.  This will be used for
example by the HMP monitor, in order to retrieve the statistics
for the currently selected CPU.

Example:
{ "execute": "query-stats",
  "arguments": {
    "target": "vcpu",
    "vcpus": [ "/machine/unattached/device[2]",
               "/machine/unattached/device[4]" ] } }

Extracted from a patch by Mark Kanda.

Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-14 16:50:30 +02:00
Mark Kanda
cc01a3f4ca kvm: Support for querying fd-based stats
Add support for querying fd-based KVM stats - as introduced by Linux kernel
commit:

cb082bfab59a ("KVM: stats: Add fd-based API to read binary stats data")

This allows the user to analyze the behavior of the VM without access
to debugfs.

Signed-off-by: Mark Kanda <mark.kanda@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-14 16:50:30 +02:00
Peter Maydell
9323e79f10 Fix 'writeable' typos
We have about 30 instances of the typo/variant spelling 'writeable',
and over 500 of the more common 'writable'.  Standardize on the
latter.

Change produced with:

  sed -i -e 's/\([Ww][Rr][Ii][Tt]\)[Ee]\([Aa][Bb][Ll][Ee]\)/\1\2/g' $(git grep -il writeable)

and then hand-undoing the instance in linux-headers/linux/kvm.h.

Most of these changes are in comments or documentation; the
exceptions are:
 * a local variable in accel/hvf/hvf-accel-ops.c
 * a local variable in accel/kvm/kvm-all.c
 * the PMCR_WRITABLE_MASK macro in target/arm/internals.h
 * the EPT_VIOLATION_GPA_WRITABLE macro in target/i386/hvf/vmcs.h
   (which is never used anywhere)
 * the AR_TYPE_WRITABLE_MASK macro in target/i386/hvf/vmx.h
   (which is never used anywhere)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Message-id: 20220505095015.2714666-1-peter.maydell@linaro.org
2022-06-08 19:38:47 +01:00
Marc-André Lureau
8e3b0cbb72 Replace qemu_real_host_page variables with inlined functions
Replace the global variables with inlined helper functions. getpagesize() is very
likely annotated with a "const" function attribute (at least with glibc), and thus
optimization should apply even better.

This avoids the need for a constructor initialization too.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220323155743.1585078-12-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-06 10:50:38 +02:00
Marc-André Lureau
ee3eb3a7ce Replace TARGET_WORDS_BIGENDIAN
Convert the TARGET_WORDS_BIGENDIAN macro, similarly to what was done
with HOST_BIG_ENDIAN. The new TARGET_BIG_ENDIAN macro is either 0 or 1,
and thus should always be defined to prevent misuse.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Suggested-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220323155743.1585078-8-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-06 10:50:37 +02:00
Marc-André Lureau
e03b56863d Replace config-time define HOST_WORDS_BIGENDIAN
Replace a config-time define with a compile time condition
define (compatible with clang and gcc) that must be declared prior to
its usage. This avoids having a global configure time define, but also
prevents from bad usage, if the config header wasn't included before.

This can help to make some code independent from qemu too.

gcc supports __BYTE_ORDER__ from about 4.6 and clang from 3.2.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[ For the s390x parts I'm involved in ]
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220323155743.1585078-7-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-06 10:50:37 +02:00
Markus Armbruster
b21e238037 Use g_new() & friends where that makes obvious sense
g_new(T, n) is neater than g_malloc(sizeof(T) * n).  It's also safer,
for two reasons.  One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.

This commit only touches allocations with size arguments of the form
sizeof(T).

Patch created mechanically with:

    $ spatch --in-place --sp-file scripts/coccinelle/use-g_new-etc.cocci \
	     --macro-file scripts/cocci-macro-file.h FILES...

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20220315144156.1595462-4-armbru@redhat.com>
Reviewed-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
2022-03-21 15:44:44 +01:00
Longpeng(Mike)
def4c5570c kvm/msi: do explicit commit when adding msi routes
We invoke the kvm_irqchip_commit_routes() for each addition to MSI route
table, which is not efficient if we are adding lots of routes in some cases.

This patch lets callers invoke the kvm_irqchip_commit_routes(), so the
callers can decide how to optimize.

[1] https://lists.gnu.org/archive/html/qemu-devel/2021-11/msg00967.html

Signed-off-by: Longpeng <longpeng2@huawei.com>
Message-Id: <20220222141116.2091-3-longpeng2@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-15 11:26:20 +01:00
Philippe Mathieu-Daudé
3919635582 accel: Introduce AccelOpsClass::cpus_are_resettable()
Add cpus_are_resettable() to AccelOps, and implement it for the
KVM accelerator.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220207075426.81934-12-f4bug@amsat.org>
2022-03-06 13:15:42 +01:00
Philippe Mathieu-Daudé
ad7d684dfd accel: Introduce AccelOpsClass::cpu_thread_is_idle()
Add cpu_thread_is_idle() to AccelOps, and implement it for the
KVM / WHPX accelerators.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220207075426.81934-11-f4bug@amsat.org>
2022-03-06 13:15:42 +01:00
Maxim Levitsky
fd2ddd1689 kvm: add support for KVM_GUESTDBG_BLOCKIRQ
Use the KVM_GUESTDBG_BLOCKIRQ debug flag if supported.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
[Extracted from Maxim's patch into a separate commit. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20211111110604.207376-6-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-10 09:47:18 +01:00
Maxim Levitsky
12bc5b4cd5 gdbstub, kvm: let KVM report supported singlestep flags
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
[Extracted from Maxim's patch into a separate commit. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20211111110604.207376-5-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-10 09:47:18 +01:00
Hyman Huang(黄勇)
7786ae40ba KVM: introduce dirty_pages and kvm_dirty_ring_enabled
dirty_pages is used to calculate dirtyrate via dirty ring, when
enabled, kvm-reaper will increase the dirty pages after gfns
being dirtied.

kvm_dirty_ring_enabled shows if kvm-reaper is working. dirtyrate
thread could use it to check if measurement can base on dirty
ring feature.

Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
Message-Id: <fee5fb2ab17ec2159405fc54a3cff8e02322f816.1624040308.git.huangy81@chinatelecom.cn>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-11-01 22:56:43 +01:00
Philippe Mathieu-Daudé
773ab6cb16 target/i386/kvm: Restrict SEV stubs to x86 architecture
SEV is x86-specific, no need to add its stub to other
architectures. Move the stub file to target/i386/kvm/.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20211007161716.453984-5-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-13 10:47:49 +02:00
Peter Xu
142518bda5 memory: Name all the memory listeners
Provide a name field for all the memory listeners.  It can be used to identify
which memory listener is which.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210817013553.30584-2-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-30 15:30:24 +02:00
Michael Tokarev
7916b5fc8c target/i386: spelling: occured=>occurred, mininum=>minimum
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Message-Id: <20210818141352.417716-1-mjt@msgid.tls.msk.ru>
[lv: add mininum=>minimum in subject]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-09-16 11:51:23 +02:00
Fabiano Rosas
380e49297c kvm: ppc: Print meaningful message on KVM_CREATE_VM failure
PowerPC has two KVM types (HV, PR) that translate into three kernel
modules:

kvm.ko - common kvm code
kvm_hv.ko - kvm running with MSR_HV=1 or MSR_HV|PR=0 in a nested guest.
kvm_pr.ko - kvm running in usermode MSR_PR=1.

Since the two KVM types can both be running at the same time, this
creates a situation in which it is possible for one or both of the
modules to fail to initialize, leaving the generic one behind. This
leads QEMU to think it can create a guest, but KVM will fail when
calling the type-specific code:

 ioctl(KVM_CREATE_VM) failed: 22 Invalid argument
 qemu-kvm: failed to initialize KVM: Invalid argument

Ideally this would be solved kernel-side, but it might be a while
until we can get rid of one of the modules. So in the meantime this
patch tries to make this less confusing for the end user by adding a
more elucidative message:

 ioctl(KVM_CREATE_VM) failed: 22 Invalid argument
 PPC KVM module is not loaded. Try 'modprobe kvm_hv'.

[dwg: Fixed error in #elif which failed compile on !ppc hosts]
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Message-Id: <20210722141340.2367905-1-farosas@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2021-07-29 10:59:49 +10:00
Peter Xu
dcafa24827 KVM: Fix dirty ring mmap incorrect size due to renaming accident
Found this when I wanted to try the per-vcpu dirty rate series out, then I
found that it's not really working and it can quickly hang death a guest.  I
found strange errors (e.g. guest crash after migration) happens even without
the per-vcpu dirty rate series.

When merging dirty ring, probably no one notice that the trivial renaming diff
[1] missed two existing references of kvm_dirty_ring_sizes; they do matter
since otherwise we'll mmap() a shorter range of memory after the renaming.

I think it didn't SIGBUS for me easily simply because some other stuff within
qemu mmap()ed right after the dirty rings (e.g. when testing 4096 slots, it
aligned with one small page on x86), so when we access the rings we've been
reading/writting to random memory elsewhere of qemu.

Fix the two sizes when map/unmap the shared dirty gfn memory.

[1] https://lore.kernel.org/qemu-devel/dac5f0c6-1bca-3daf-e5d2-6451dbbaca93@redhat.com/

Cc: Hyman Huang <huangy81@chinatelecom.cn>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210609014355.217110-1-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-06-25 10:54:12 +02:00
Stefano Garzarella
d0fb9657a3 docs: fix references to docs/devel/tracing.rst
Commit e50caf4a5c ("tracing: convert documentation to rST")
converted docs/devel/tracing.txt to docs/devel/tracing.rst.

We still have several references to the old file, so let's fix them
with the following command:

  sed -i s/tracing.txt/tracing.rst/ $(git grep -l docs/devel/tracing.txt)

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210517151702.109066-2-sgarzare@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-06-02 06:51:09 +02:00
Peter Xu
b4420f198d KVM: Dirty ring support
KVM dirty ring is a new interface to pass over dirty bits from kernel to the
userspace.  Instead of using a bitmap for each memory region, the dirty ring
contains an array of dirtied GPAs to fetch (in the form of offset in slots).
For each vcpu there will be one dirty ring that binds to it.

kvm_dirty_ring_reap() is the major function to collect dirty rings.  It can be
called either by a standalone reaper thread that runs in the background,
collecting dirty pages for the whole VM.  It can also be called directly by any
thread that has BQL taken.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-11-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-26 14:49:46 +02:00
Peter Xu
a81a592698 KVM: Disable manual dirty log when dirty ring enabled
KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is for KVM_CLEAR_DIRTY_LOG, which is only
useful for KVM_GET_DIRTY_LOG.  Skip enabling it for kvm dirty ring.

More importantly, KVM_DIRTY_LOG_INITIALLY_SET will not wr-protect all the pages
initially, which is against how kvm dirty ring is used - there's no way for kvm
dirty ring to re-protect a page before it's notified as being written first
with a GFN entry in the ring!  So when KVM_DIRTY_LOG_INITIALLY_SET is enabled
with dirty ring, we'll see silent data loss after migration.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-10-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-26 14:49:46 +02:00
Peter Xu
2ea5cb0a47 KVM: Add dirty-ring-size property
Add a parameter for dirty gfn count for dirty rings.  If zero, dirty ring is
disabled.  Otherwise dirty ring will be enabled with the per-vcpu gfn count as
specified.  If dirty ring cannot be enabled due to unsupported kernel or
illegal parameter, it'll fallback to dirty logging.

By default, dirty ring is not enabled (dirty-gfn-count default to 0).

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-9-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-26 14:49:45 +02:00
Peter Xu
563d32ba9b KVM: Cache kvm slot dirty bitmap size
Cache it too because we'll reference it more frequently in the future.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-8-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-26 14:49:45 +02:00
Peter Xu
29b7e8be76 KVM: Simplify dirty log sync in kvm_set_phys_mem
kvm_physical_sync_dirty_bitmap() on the whole section is inaccurate, because
the section can be a superset of the memslot that we're working on.  The result
is that if the section covers multiple kvm memslots, we could be doing the
synchronization for multiple times for each kvmslot in the section.

With the two helpers that we just introduced, it's very easy to do it right now
by calling the helpers.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-7-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-26 14:49:45 +02:00
Peter Xu
2c20b27eed KVM: Provide helper to sync dirty bitmap from slot to ramblock
kvm_physical_sync_dirty_bitmap() calculates the ramblock offset in an
awkward way from the MemoryRegionSection that passed in from the
caller.  The truth is for each KVMSlot the ramblock offset never
change for the lifecycle.  Cache the ramblock offset for each KVMSlot
into the structure when the KVMSlot is created.

With that, we can further simplify kvm_physical_sync_dirty_bitmap()
with a helper to sync KVMSlot dirty bitmap to the ramblock dirty
bitmap of a specific KVMSlot.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-6-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-26 14:49:45 +02:00
Peter Xu
e65e5f50db KVM: Provide helper to get kvm dirty log
Provide a helper kvm_slot_get_dirty_log() to make the function
kvm_physical_sync_dirty_bitmap() clearer.  We can even cache the as_id
into KVMSlot when it is created, so that we don't even need to pass it
down every time.

Since at it, remove return value of kvm_physical_sync_dirty_bitmap()
because it should never fail.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-5-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-26 14:49:45 +02:00
Peter Xu
ea776d15ad KVM: Create the KVMSlot dirty bitmap on flag changes
Previously we have two places that will create the per KVMSlot dirty
bitmap:

  1. When a newly created KVMSlot has dirty logging enabled,
  2. When the first log_sync() happens for a memory slot.

The 2nd case is lazy-init, while the 1st case is not (which is a fix
of what the 2nd case missed).

To do explicit initialization of dirty bitmaps, what we're missing is
to create the dirty bitmap when the slot changed from not-dirty-track
to dirty-track.  Do that in kvm_slot_update_flags().

With that, we can safely remove the 2nd lazy-init.

This change will be needed for kvm dirty ring because kvm dirty ring
does not use the log_sync() interface at all.

Also move all the pre-checks into kvm_slot_init_dirty_bitmap().

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-4-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-26 14:49:45 +02:00
Peter Xu
a2f77862ff KVM: Use a big lock to replace per-kml slots_lock
Per-kml slots_lock will bring some trouble if we want to take all slots_lock of
all the KMLs, especially when we're in a context that we could have taken some
of the KML slots_lock, then we even need to figure out what we've taken and
what we need to take.

Make this simple by merging all KML slots_lock into a single slots lock.

Per-kml slots_lock isn't anything that helpful anyway - so far only x86 has two
address spaces (so, two slots_locks).  All the rest archs will be having one
address space always, which means there's actually one slots_lock so it will be
the same as before.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-3-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-26 14:49:45 +02:00
Paolo Bonzini
70cbae429e KVM: do not allow setting properties at runtime
Only allow accelerator properties to be set when the
accelerator is being created.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-26 14:49:45 +02:00
Thomas Huth
ee86213aa3 Do not include exec/address-spaces.h if it's not really necessary
Stop including exec/address-spaces.h in files that don't need it.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-5-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-05-02 17:24:51 +02:00
Thomas Huth
4c386f8064 Do not include sysemu/sysemu.h if it's not really necessary
Stop including sysemu/sysemu.h in files that don't need it.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-2-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-05-02 17:24:50 +02:00
David Edmondson
56567da376 accel: kvm: clarify that extra exit data is hexadecimal
When dumping the extra exit data provided by KVM, make it clear that
the data is hexadecimal.

At the same time, zero-pad the output.

Signed-off-by: David Edmondson <david.edmondson@oracle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210428142431.266879-1-david.edmondson@oracle.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-05-02 17:24:50 +02:00
Paolo Bonzini
26dbec410e Revert "accel: kvm: Add aligment assert for kvm_log_clear_one_slot"
This reverts commit 3920552846.
Thomas Huth reported a failure with CentOS 6 guests:

../../devel/qemu/accel/kvm/kvm-all.c:690: kvm_log_clear_one_slot: Assertion `QEMU_IS_ALIGNED(start | size, psize)' failed.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-16 14:30:30 -04:00
Andrew Jones
516fc0a081 accel: kvm: Fix kvm_type invocation
Prior to commit f2ce39b4f0 a MachineClass kvm_type method
only needed to be registered to ensure it would be executed.
With commit f2ce39b4f0 a kvm-type machine property must also
be specified. hw/arm/virt relies on the kvm_type method to pass
its selected IPA limit to KVM, but this is not exposed as a
machine property. Restore the previous functionality of invoking
kvm_type when it's present.

Fixes: f2ce39b4f0 ("vl: make qemu_get_machine_opts static")
Signed-off-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-id: 20210310135218.255205-2-drjones@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-03-12 12:47:11 +00:00
Keqian Zhu
3920552846 accel: kvm: Add aligment assert for kvm_log_clear_one_slot
The parameters start and size are transfered from QEMU memory
emulation layer. It can promise that they are TARGET_PAGE_SIZE
aligned. However, KVM needs they are qemu_real_page_size aligned.

Though no caller breaks this aligned requirement currently, we'd
better add an explicit assert to avoid future breaking.

Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Message-Id: <20201217014941.22872-3-zhukeqian1@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-06 11:41:54 +01:00
Keqian Zhu
e0a8f99355 accel: kvm: Fix memory waste under mismatch page size
When handle dirty log, we face qemu_real_host_page_size and
TARGET_PAGE_SIZE. The first one is the granule of KVM dirty
bitmap, and the second one is the granule of QEMU dirty bitmap.

As qemu_real_host_page_size >= TARGET_PAGE_SIZE (kvm_init()
enforced it), misuse TARGET_PAGE_SIZE to init kvmslot dirty_bmap
may waste memory. For example, when qemu_real_host_page_size is
64K and TARGET_PAGE_SIZE is 4K, it wastes 93.75% (15/16) memory.

Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20201217014941.22872-2-zhukeqian1@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-06 11:41:54 +01:00
Tom Lendacky
92a5199b29 sev/i386: Don't allow a system reset under an SEV-ES guest
An SEV-ES guest does not allow register state to be altered once it has
been measured. When an SEV-ES guest issues a reboot command, Qemu will
reset the vCPU state and resume the guest. This will cause failures under
SEV-ES. Prevent that from occuring by introducing an arch-specific
callback that returns a boolean indicating whether vCPUs are resettable.

Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Aleksandar Rikalo <aleksandar.rikalo@syrmia.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: David Hildenbrand <david@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Venu Busireddy <venu.busireddy@oracle.com>
Message-Id: <1ac39c441b9a3e970e9556e1cc29d0a0814de6fd.1611682609.git.thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-16 17:15:39 +01:00
Paolo Bonzini
b2f73a0784 sev/i386: Allow AP booting under SEV-ES
When SEV-ES is enabled, it is not possible modify the guests register
state after it has been initially created, encrypted and measured.

Normally, an INIT-SIPI-SIPI request is used to boot the AP. However, the
hypervisor cannot emulate this because it cannot update the AP register
state. For the very first boot by an AP, the reset vector CS segment
value and the EIP value must be programmed before the register has been
encrypted and measured. Search the guest firmware for the guest for a
specific GUID that tells Qemu the value of the reset vector to use.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <22db2bfb4d6551aed661a9ae95b4fdbef613ca21.1611682609.git.thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-16 17:15:39 +01:00
Thomas Huth
38e0b7904e accel/kvm/kvm-all: Fix wrong return code handling in dirty log code
The kvm_vm_ioctl() wrapper already returns -errno if the ioctl itself
returned -1, so the callers of kvm_vm_ioctl() should not check for -1
but for a value < 0 instead.

This problem has been fixed once already in commit b533f658a9
but that commit missed that the ENOENT error code is not fatal for
this ioctl, so the commit has been reverted in commit 50212d6346
since the problem occurred close to a pending release at that point
in time. The plan was to fix it properly after the release, but it
seems like this has been forgotten. So let's do it now finally instead.

Resolves: https://bugs.launchpad.net/qemu/+bug/1294227
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210129084354.42928-1-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-08 14:43:55 +01:00
David Gibson
ec78e2cda3 confidential guest support: Move SEV initialization into arch specific code
While we've abstracted some (potential) differences between mechanisms for
securing guest memory, the initialization is still specific to SEV.  Given
that, move it into x86's kvm_arch_init() code, rather than the generic
kvm_init() code.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
2021-02-08 16:57:38 +11:00
David Gibson
c9f5aaa6bc sev: Add Error ** to sev_kvm_init()
This allows failures to be reported richly and idiomatically.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2021-02-08 16:57:38 +11:00
David Gibson
e0292d7c62 confidential guest support: Rework the "memory-encryption" property
Currently the "memory-encryption" property is only looked at once we
get to kvm_init().  Although protection of guest memory from the
hypervisor isn't something that could really ever work with TCG, it's
not conceptually tied to the KVM accelerator.

In addition, the way the string property is resolved to an object is
almost identical to how a QOM link property is handled.

So, create a new "confidential-guest-support" link property which sets
this QOM interface link directly in the machine.  For compatibility we
keep the "memory-encryption" property, but now implemented in terms of
the new property.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2021-02-08 16:57:38 +11:00
David Gibson
aacdb84413 sev: Remove false abstraction of flash encryption
When AMD's SEV memory encryption is in use, flash memory banks (which are
initialed by pc_system_flash_map()) need to be encrypted with the guest's
key, so that the guest can read them.

That's abstracted via the kvm_memcrypt_encrypt_data() callback in the KVM
state.. except, that it doesn't really abstract much at all.

For starters, the only call site is in code specific to the 'pc'
family of machine types, so it's obviously specific to those and to
x86 to begin with.  But it makes a bunch of further assumptions that
need not be true about an arbitrary confidential guest system based on
memory encryption, let alone one based on other mechanisms:

 * it assumes that the flash memory is defined to be encrypted with the
   guest key, rather than being shared with hypervisor
 * it assumes that that hypervisor has some mechanism to encrypt data into
   the guest, even though it can't decrypt it out, since that's the whole
   point
 * the interface assumes that this encrypt can be done in place, which
   implies that the hypervisor can write into a confidential guests's
   memory, even if what it writes isn't meaningful

So really, this "abstraction" is actually pretty specific to the way SEV
works.  So, this patch removes it and instead has the PC flash
initialization code call into a SEV specific callback.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2021-02-08 16:57:38 +11:00
Claudio Fontana
b86f59c715 accel: replace struct CpusAccel with AccelOpsClass
This will allow us to centralize the registration of
the cpus.c module accelerator operations (in accel/accel-softmmu.c),
and trigger it automatically using object hierarchy lookup from the
new accel_init_interfaces() initialization step, depending just on
which accelerators are available in the code.

Rename all tcg-cpus.c, kvm-cpus.c, etc to tcg-accel-ops.c,
kvm-accel-ops.c, etc, matching the object type names.

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Message-Id: <20210204163931.7358-18-cfontana@suse.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-02-05 10:24:15 -10:00
Jiaxun Yang
eb8b1a797a accel/kvm: avoid using predefined PAGE_SIZE
As per POSIX specification of limits.h [1], OS libc may define
PAGE_SIZE in limits.h.

PAGE_SIZE is used in included kernel uapi headers.

To prevent collosion of definition, we discard PAGE_SIZE from
defined by libc and take QEMU's variable.

[1]: https://pubs.opengroup.org/onlinepubs/7908799/xsh/limits.h.html

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Message-Id: <20210118063808.12471-8-jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-01-20 10:46:54 +01:00
Zenghui Yu
4054adbdd2 kvm: Take into account the unaligned section size when preparing bitmap
The kernel KVM_CLEAR_DIRTY_LOG interface has align requirement on both the
start and the size of the given range of pages. We have been careful to
handle the unaligned cases when performing CLEAR on one slot. But it seems
that we forget to take the unaligned *size* case into account when
preparing bitmap for the interface, and we may end up clearing dirty status
for pages outside of [start, start + size).

If the size is unaligned, let's go through the slow path to manipulate a
temp bitmap for the interface so that we won't bother with those unaligned
bits at the end of bitmap.

I don't think this can happen in practice since the upper layer would
provide us with the alignment guarantee. I'm not sure if kvm-all could rely
on it. And this patch is mainly intended to address correctness of the
specific algorithm used inside kvm_log_clear_one_slot().

Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Message-Id: <20201208114013.875-1-yuzenghui@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-15 12:52:05 -05:00