450 Commits
Author SHA1 Message Date
Peter MaydellandPeter Xu 300a87c502 physmem: Destroy all CPU AddressSpaces on unrealize
When we unrealize a CPU object (which happens on vCPU hot-unplug), we
should destroy all the AddressSpace objects we created via calls to
cpu_address_space_init() when the CPU was realized.

Commit 24bec42f3d added a function to do this for a specific
AddressSpace, but did not add any places where the function was
called.

Since we always want to destroy all the AddressSpaces on unrealize,
regardless of the target architecture, we don't need to try to keep
track of how many are still undestroyed, or make the target
architecture code manually call a destroy function for each AS it
created.  Instead we can adjust the function to always completely
destroy the whole cpu->ases array, and arrange for it to be called
during CPU unrealize as part of the common code.

Without this fix, AddressSanitizer will report a leak like this
from a run where we hot-plugged and then hot-unplugged an x86 KVM
vCPU:

Direct leak of 416 byte(s) in 1 object(s) allocated from:
    #0 0x5b638565053d in calloc (/data_nvme1n1/linaro/qemu-from-laptop/qemu/build/x86-tgts-asan/qemu-system-x86_64+0x1ee153d) (BuildId: c1cd6022b195142106e1bffeca23498c2b752bca)
    #1 0x7c28083f77b1 in g_malloc0 (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x637b1) (BuildId: 1eb6131419edb83b2178b682829a6913cf682d75)
    #2 0x5b6386999c7c in cpu_address_space_init /data_nvme1n1/linaro/qemu-from-laptop/qemu/build/x86-tgts-asan/../../system/physmem.c:797:25
    #3 0x5b638727f049 in kvm_cpu_realizefn /data_nvme1n1/linaro/qemu-from-laptop/qemu/build/x86-tgts-asan/../../target/i386/kvm/kvm-cpu.c:102:5
    #4 0x5b6385745f40 in accel_cpu_common_realize /data_nvme1n1/linaro/qemu-from-laptop/qemu/build/x86-tgts-asan/../../accel/accel-common.c:101:13
    #5 0x5b638568fe3c in cpu_exec_realizefn /data_nvme1n1/linaro/qemu-from-laptop/qemu/build/x86-tgts-asan/../../hw/core/cpu-common.c:232:10
    #6 0x5b63874a2cd5 in x86_cpu_realizefn /data_nvme1n1/linaro/qemu-from-laptop/qemu/build/x86-tgts-asan/../../target/i386/cpu.c:9321:5
    #7 0x5b6387a0469a in device_set_realized /data_nvme1n1/linaro/qemu-from-laptop/qemu/build/x86-tgts-asan/../../hw/core/qdev.c:494:13
    #8 0x5b6387a27d9e in property_set_bool /data_nvme1n1/linaro/qemu-from-laptop/qemu/build/x86-tgts-asan/../../qom/object.c:2375:5
    #9 0x5b6387a2090b in object_property_set /data_nvme1n1/linaro/qemu-from-laptop/qemu/build/x86-tgts-asan/../../qom/object.c:1450:5
    #10 0x5b6387a35b05 in object_property_set_qobject /data_nvme1n1/linaro/qemu-from-laptop/qemu/build/x86-tgts-asan/../../qom/qom-qobject.c:28:10
    #11 0x5b6387a21739 in object_property_set_bool /data_nvme1n1/linaro/qemu-from-laptop/qemu/build/x86-tgts-asan/../../qom/object.c:1520:15
    #12 0x5b63879fe510 in qdev_realize /data_nvme1n1/linaro/qemu-from-laptop/qemu/build/x86-tgts-asan/../../hw/core/qdev.c:276:12

Cc: qemu-stable@nongnu.org
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2517
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20250929144228.1994037-4-peter.maydell@linaro.org
Signed-off-by: Peter Xu <peterx@redhat.com>
2025-10-03 09:48:02 -04:00
Peter Xu 041600e23f memory: New AS helper to serialize destroy+free
If an AddressSpace has been created in its own allocated
memory, cleaning it up requires first destroying the AS
and then freeing the memory. Doing this doesn't work:

    address_space_destroy(as);
    g_free_rcu(as, rcu);

because both address_space_destroy() and g_free_rcu()
try to use the same 'rcu' node in the AddressSpace struct
and the address_space_destroy hook gets overwritten.

Provide a new address_space_destroy_free() function which
will destroy the AS and then free the memory it uses, all
in one RCU callback.

(CC to stable because the next commit needs this function.)

Cc: qemu-stable@nongnu.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20250929144228.1994037-3-peter.maydell@linaro.org
Signed-off-by: Peter Xu <peterx@redhat.com>
2025-10-03 09:48:02 -04:00
Richard Henderson ccafa85a97 Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into staging
* cpu-exec: more cleanups to CPU loop exits
* python: bump bundled Meson to 1.9.0
* rust: require Rust 1.83.0
* rust: temporarily remove from Ubuntu CI
* rust: vmstate: convert to use builder pattern
* rust: split "qemu-api" crate
* rust: rename qemu_api_macros -> qemu_macros
* rust: re-export qemu macros from other crates
* x86: fix functional test failure for Xen emulation
* x86: cleanups

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* tag 'for-upstream' of https://gitlab.com/bonzini/qemu: (60 commits)
  accel/kvm: Set guest_memfd_offset to non-zero value only when guest_memfd is valid
  accel/kvm: Zero out mem explicitly in kvm_set_user_memory_region()
  accel/kvm: Switch to check KVM_CAP_GUEST_MEMFD and KVM_CAP_USER_MEMORY2 on VM
  i386/kvm: Drop KVM_CAP_X86_SMM check in kvm_arch_init()
  multiboot: Fix the split lock
  target/i386: Define enum X86ASIdx for x86's address spaces
  i386/cpu: Enable SMM cpu address space under KVM
  hpet: guard IRQ handling with BQL
  rust: do not inline do_init_io
  rust: meson: remove unnecessary complication in device crates
  docs: update rust.rst
  rust: re-export qemu macros from common/qom/hwcore
  rust: re-export qemu_macros internal helper in "bits"
  rust: repurpose qemu_api -> tests
  rust/pl011: drop dependency on qemu_api
  rust/hpet: drop now unneeded qemu_api dep
  rust: rename qemu_api_macros -> qemu_macros
  rust: split "hwcore" crate
  rust: split "system" crate
  rust: split "chardev" crate
  ...

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2025-09-18 07:05:59 -07:00
Richard Henderson f0007b7f03 Merge tag 'pull-target-arm-20250916' of https://gitlab.com/pm215/qemu into staging
target-arm queue:
 * tests, scripts: Don't import print_function from __future__
 * Implement FEAT_ATS1A
 * Remove deprecated pxa CPU family
 * arm/kvm: report registers we failed to set
 * Expose SME registers to GDB via gdbstub
 * linux-user/aarch64: Generate ESR signal records
 * hw/arm/raspi4b: remove redundant check in raspi_add_memory_node
 * hw/arm/virt: Allow user-creatable SMMUv3 dev instantiation
 * system: drop the -old-param option

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# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>" [unknown]
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>" [unknown]
# gpg:                 aka "Peter Maydell <peter@archaic.org.uk>" [unknown]
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# gpg:          There is no indication that the signature belongs to the owner.
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* tag 'pull-target-arm-20250916' of https://gitlab.com/pm215/qemu: (36 commits)
  hw/usb/network: Remove hardcoded 0x40 prefix in STRING_ETHADDR response
  qtest/bios-tables-test: Update tables for smmuv3 tests
  qtest/bios-tables-test: Add tests for legacy smmuv3 and smmuv3 device
  bios-tables-test: Allow for smmuv3 test data.
  qemu-options.hx: Document the arm-smmuv3 device
  hw/arm/virt: Allow user-creatable SMMUv3 dev instantiation
  hw/pci: Introduce pci_setup_iommu_per_bus() for per-bus IOMMU ops retrieval
  hw/arm/virt: Add an SMMU_IO_LEN macro
  hw/arm/virt: Factor out common SMMUV3 dt bindings code
  hw/arm/virt-acpi-build: Update IORT for multiple smmuv3 devices
  hw/arm/virt-acpi-build: Re-arrange SMMUv3 IORT build
  hw/arm/smmu-common: Check SMMU has PCIe Root Complex association
  target/arm: Added test case for SME register exposure to GDB
  target/arm: Added support for SME register exposure to GDB
  target/arm: Increase MAX_PACKET_LENGTH for SME ZA remote gdb debugging
  arm/kvm: report registers we failed to set
  system: drop the -old-param option
  target/arm: Drop ARM_FEATURE_IWMMXT handling
  target/arm: Drop ARM_FEATURE_XSCALE handling
  target/arm: Remove iwmmxt helper functions
  ...

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2025-09-17 11:10:55 -07:00
Xiaoyao LiandPaolo Bonzini 0516f4b702 i386/cpu: Enable SMM cpu address space under KVM
Kirill Martynov reported assertation in cpu_asidx_from_attrs() being hit
when x86_cpu_dump_state() is called to dump the CPU state[*]. It happens
when the CPU is in SMM and KVM emulation failure due to misbehaving
guest.

The root cause is that QEMU i386 never enables the SMM address space for
cpu since KVM SMM support has been added.

Enable the SMM cpu address space under KVM when the SMM is enabled for
the x86machine.

[*] https://lore.kernel.org/qemu-devel/20250523154431.506993-1-stdcalllevi@yandex-team.ru/

Reported-by: Kirill Martynov <stdcalllevi@yandex-team.ru>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Tested-by: Kirill Martynov <stdcalllevi@yandex-team.ru>
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20250730095253.1833411-2-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-09-17 19:00:58 +02:00
Paolo Bonzini 9a191d3782 cpus: clear exit_request in qemu_process_cpu_events
Make the code common to all accelerators: after seeing cpu->exit_request
set to true, accelerator code needs to reach qemu_process_cpu_events_common().

So for the common cases where they use qemu_process_cpu_events(), go ahead and
clear it in there.  Note that the cheap qatomic_set() is enough because
at this point the thread has taken the BQL; qatomic_set_mb() is not needed.
In particular, this is the ordering of the communication between
I/O and vCPU threads is always the same.

In the I/O thread:

(a) store other memory locations that will be checked if cpu->exit_request
    or cpu->interrupt_request is 1 (for example cpu->stop or cpu->work_list
    for cpu->exit_request)

(b) cpu_exit(): store-release cpu->exit_request, or
(b) cpu_interrupt(): store-release cpu->interrupt_request

>>> at this point, cpu->halt_cond is broadcast and the BQL released

(c) do the accelerator-specific kick (e.g. write icount_decr for TCG,
    pthread_kill for KVM, etc.)

In the vCPU thread instead the opposite order is respected:

(c) the accelerator's execution loop exits thanks to the kick

(b) then the inner execution loop checks cpu->interrupt_request
    and cpu->exit_request.  If needed cpu->interrupt_request is
    converted into cpu->exit_request when work is needed outside
    the execution loop.

(a) then the other memory locations are checked.  Some may need to
    be read under the BQL, but the vCPU thread may also take other
    locks (e.g. for queued work items) or none at all.

qatomic_set_mb() would only be needed if the halt sleep was done
outside the BQL (though in that case, cpu->exit_request probably
would be replaced by a QemuEvent or something like that).

Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-09-17 19:00:56 +02:00
Paolo Bonzini 871de7078f treewide: rename qemu_wait_io_event/qemu_wait_io_event_common
Do so before extending it to the user-mode emulators, where there is no
such thing as an "I/O thread".

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-09-17 19:00:55 +02:00
Paolo Bonzini f8217ae54e cpus: properly kick CPUs out of inner execution loop
Now that cpu_exit() actually kicks all accelerators, use it whenever
the message to another thread is processed in qemu_wait_io_event().

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-09-17 19:00:55 +02:00
Paolo Bonzini 27e76d0101 cpu-common: use atomic access for interrupt_request
Writes to interrupt_request used non-atomic accesses, but there are a
few cases where the access was not protected by the BQL.  Now that
there is a full set of helpers, it's easier to guarantee that
interrupt_request accesses are fully atomic, so just drop the
requirement instead of fixing them.

Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-09-17 19:00:55 +02:00
Peter Maydell 116c2c21d5 system: drop the -old-param option
We deprecated the command line option -old-param for the 10.0
release, which allows us to drop it in 10.2.  This option was used to
boot Arm targets with a very old boot protocol using the
'param_struct' ABI.  We only ever needed this on a handful of board
types which have all now been removed from QEMU.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20250828162700.3308812-1-peter.maydell@linaro.org
2025-09-16 17:31:54 +01:00
Peter Xu ac7a892fd3 memory: Fix leaks due to owner-shared MRs circular references
Currently, QEMU refcounts the MR by always taking it from the owner.

It's common that one object will have multiple MR objects embeded in the
object itself.  All the MRs in this case share the same lifespan of the
owner object.

It's also common that in the instance_init() of an object, MR A can be a
container of MR B, C, D, by using memory_region_add_subregion*() set of
memory region APIs.

Now we have a circular reference issue, as when adding subregions for MR A,
we essentially incremented the owner's refcount within the instance_init(),
meaning the object will be self-boosted and its refcount can never go down
to zero if the MRs won't get detached properly before object's finalize().

Delete subregions within object's finalize() won't work either, because
finalize() will be invoked only if the refcount goes to zero first.  What
is worse, object_finalize() will do object_property_del_all() first before
object_deinit().  Since embeded MRs will be properties of the owner object,
it means they'll be freed _before_ the owner's finalize().

To fix that, teach memory API to stop refcount on MRs that share the same
owner.  Because if they share the lifecycle of the owner, then they share
the same lifecycle between themselves, hence the refcount doesn't help but
only introduce troubles.

Meanwhile, allow auto-detachments of MRs during finalize() of MRs even
against its container, as long as they belong to the same owner.

The latter is needed because now it's possible to have MRs' finalize()
happen in any order when they share the same lifespan with a same owner.
In this case, we should allow finalize() to happen in any order of either
the parent or child MR.  Loose the mr->container check in MR's finalize()
to allow auto-detach.  Double check it shares the same owner.

Proper document this behavior in code.

This patch is heavily based on the work done by Akihiko Odaki:

https://lore.kernel.org/r/CAFEAcA8DV40fGsci76r4yeP1P-SP_QjNRDD2OzPxjx5wRs0GEg@mail.gmail.com

Cc: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Clément Mathieu--Drif <clement.mathieu--drif@eviden.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Peter Maydell <peter.maydell@linaro.org>
Link: https://lore.kernel.org/r/20250826221750.285242-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
2025-09-15 12:00:12 -04:00
Peter Xu c75847f9eb memory: Fix addr/len for flatview_access_allowed()
flatview_access_allowed() should pass in the address offset of the memory
region, rather than the global address space. Shouldn't be a major issue
yet, since the addr is only used in an error log.

Cc: Philippe Mathieu-Daudé <philmd@linaro.org>
Fixes: 3ab6fdc91b ("softmmu/physmem: Introduce MemTxAttrs::memory field and MEMTX_ACCESS_ERROR")
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20250903142932.1038765-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
2025-09-15 12:00:12 -04:00
Thomas Huth 2dbaf58bbe system/physmem: Silence warning from ubsan
When compiling QEMU with --enable-ubsan there is a undefined behavior
warning when running the bios-tables-test for example:

 .../system/physmem.c:3243:13: runtime error: applying non-zero offset 262144 to null pointer
    #0 0x55ac1df5fbc4 in address_space_write_rom_internal .../system/physmem.c:3243:13

The problem is that buf is indeed NULL if the function is e.g. called
with type == FLUSH_CACHE. Add a check to fix the issue.

Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-ID: <20250728172545.314178-1-thuth@redhat.com>
2025-09-09 09:35:55 +02:00
Igor MammedovandPaolo Bonzini 73c520b088 memory: reintroduce BQL-free fine-grained PIO/MMIO
This patch brings back Jan's idea [1] of BQL-free IO access

This will let us make access to ACPI PM/HPET timers cheaper,
and prevent BQL contention in case of workload that heavily
uses the timers with a lot of vCPUs.

1) 196ea13104 (memory: Add global-locking property to memory regions)
   ... de7ea885c5 (kvm: Switch to unlocked MMIO)

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20250814160600.2327672-2-imammedo@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-08-29 12:48:14 +02:00
Igor MammedovandPaolo Bonzini 87511341c3 add cpu_test_interrupt()/cpu_set_interrupt() helpers and use them tree wide
The helpers form load-acquire/store-release pair and ensure
that appropriate barriers are in place in case checks happen
outside of BQL.

Use them to replace open-coded checkers/setters across the code,
to make sure that barriers are not missed.  Helpers also make code a
bit more readable.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
Link: https://lore.kernel.org/r/20250821155603.2422553-1-imammedo@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-08-29 12:48:14 +02:00
Pierrick BouvierandPhilippe Mathieu-Daudé 2865bf1c57 system/physmem: fix use-after-free with dispatch
A use-after-free bug was reported when booting a Linux kernel during the
pci setup phase. It's quite hard to reproduce (needs smp, and favored by
having several pci devices with BAR and specific Linux config, which
is Debian default one in this case).

After investigation (see the associated bug ticket), it appears that,
under specific conditions, we might access a cached AddressSpaceDispatch
that was reclaimed by RCU thread meanwhile.
In the Linux boot scenario, during the pci phase, memory region are
destroyed/recreated, resulting in exposition of the bug.

The core of the issue is that we cache the dispatch associated to
current cpu in cpu->cpu_ases[asidx].memory_dispatch. It is updated with
tcg_commit, which runs asynchronously on a given cpu.
At some point, we leave the rcu critial section, and the RCU thread
starts reclaiming it, but tcg_commit is not yet invoked, resulting in
the use-after-free.

It's not the first problem around this area, and commit 0d58c66068 [1]
("softmmu: Use async_run_on_cpu in tcg_commit") already tried to
address it. It did a good job, but it seems that we found a specific
situation where it's not enough.

This patch takes a simple approach: remove the cached value creating the
issue, and make sure we always get the current mapping for address
space, using address_space_to_dispatch(cpu->cpu_ases[asidx].as).
It's equivalent to qatomic_rcu_read(&as->current_map)->dispatch;
This is not really costly, we just need two dereferences,
including one atomic (rcu) read, which is negligible considering we are
already on mmu slow path anyway.

Note that tcg_commit is still needed, as it's taking care of flushing
TLB, removing previously mapped entries.

Another solution would be to cache directly values under the dispatch
(dispatch themselves are not ref counted), keep an active reference on
associated memory section, and release it when appropriate (tricky).
Given the time already spent debugging this area now and previously, I
strongly prefer eliminating the root of the issue, instead of adding
more complexity for a hypothetical performance gain. RCU is precisely
used to ensure good performance when reading data, so caching is not as
beneficial as it might seem IMHO.

[1] https://gitlab.com/qemu-project/qemu/-/commit/0d58c660689f6da1e3feff8a997014003d928b3b

Cc: qemu-stable@nongnu.org
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/3040
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Tested-by: Michael Tokarev <mjt@tls.msk.ru>
Message-ID: <20250724161142.2803091-1-pierrick.bouvier@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2025-07-29 13:56:39 +02:00
Stefan Hajnoczi f96b157ebb Merge tag 'accel-20250715' of https://github.com/philmd/qemu into staging
Accelerators patches

- Unify x86/arm hw/xen/arch_hvm.h header
- Move non-system-specific 'accel/accel-ops.h' and 'accel-cpu-ops.h' to accel/
- Move KVM definitions qapi/accelerator.json
- Add @qom-type field to CpuInfoFast QAPI structure
- Display CPU model name in 'info cpus' HMP command
- Introduce @x-accel-stats QMP command
- Add 'info accel' on HMP
- Improve qemu_add_vm_change_state_handler*() docstring
- Extract TCG statistic related code to tcg-stats.c
- Implement AccelClass::get_[vcpu]_stats() handlers for TCG and HVF
- Do not dump NaN in TCG statistics
- Revert incomplete "accel/tcg: Unregister the RCU before exiting RR thread"

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* tag 'accel-20250715' of https://github.com/philmd/qemu:
  system/runstate: Document qemu_add_vm_change_state_handler_prio* in hdr
  system/runstate: Document qemu_add_vm_change_state_handler()
  accel/hvf: Implement AccelClass::get_vcpu_stats() handler
  accel/tcg: Implement AccelClass::get_stats() handler
  accel/tcg: Propagate AccelState to dump_accel_info()
  accel/system: Add 'info accel' on human monitor
  accel/system: Introduce @x-accel-stats QMP command
  accel/tcg: Extract statistic related code to tcg-stats.c
  Revert "accel/tcg: Unregister the RCU before exiting RR thread"
  accel: Extract AccelClass definition to 'accel/accel-ops.h'
  accel: Rename 'system/accel-ops.h' -> 'accel/accel-cpu-ops.h'
  accel/tcg: Do not dump NaN statistics
  hw/core/machine: Display CPU model name in 'info cpus' command
  qapi/machine: Add @qom-type field to CpuInfoFast structure
  qapi/accel: Move definitions related to accelerators in their own file
  hw/arm/xen-pvh: Remove unnecessary 'hw/xen/arch_hvm.h' header
  hw/xen/arch_hvm: Unify x86 and ARM variants

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Conflicts:
  qapi/machine.json
  Commit 0462da9d6b ("qapi: remove trivial "Returns:" sections")
  removed trivial "Returns:". This caused a conflict with the move from
  machine.json to accelerator.json.
2025-07-16 07:13:40 -04:00
Stefan Hajnoczi 1c37425423 Merge tag 'ui-pull-request' of https://gitlab.com/marcandre.lureau/qemu into staging
UI-related for 10.1

- [PATCH v3 0/2] ui/vnc: Do not copy z_stream
- [PATCH v6 0/7] ui/spice: Enable gl=on option for non-local or remote clients
- [PATCH v6 0/1] Allow injection of virtio-gpu EDID name
- [PATCH 0/2] ui/gtk: Add keep-aspect-ratio and scale option

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* tag 'ui-pull-request' of https://gitlab.com/marcandre.lureau/qemu:
  tpm: "qemu -tpmdev help" should return success
  ui/gtk: Add scale option
  ui/gtk: Add keep-aspect-ratio option
  hw/display: Allow injection of virtio-gpu EDID name
  ui/spice: Blit the scanout texture if its memory layout is not linear
  ui/spice: Create a new texture with linear layout when gl=on is specified
  ui/console-gl: Add a helper to create a texture with linear memory layout
  ui/spice: Add an option to submit gl_draw requests at fixed rate
  ui/spice: Add an option for users to provide a preferred video codec
  ui/spice: Enable gl=on option for non-local or remote clients
  ui/egl-helpers: Error check the fds in egl_dmabuf_export_texture()
  ui/vnc: Introduce the VncWorker type
  ui/vnc: Do not copy z_stream

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2025-07-16 07:07:05 -04:00
Philippe Mathieu-Daudé 0a94a7b880 system/runstate: Document qemu_add_vm_change_state_handler_prio* in hdr
Generally APIs to the rest of QEMU should be documented in the headers.
Comments on individual functions or internal details are fine to live
in the C files. Make qemu_add_vm_change_state_handler_prio[_full]()
docstrings consistent by moving them from source to header.

Suggested-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20250715171920.89670-1-philmd@linaro.org>
2025-07-15 21:42:58 +02:00
Philippe Mathieu-Daudé f7a7e7dd21 accel: Extract AccelClass definition to 'accel/accel-ops.h'
Only accelerator implementations (and the common accelator
code) need to know about AccelClass internals. Move the
definition out but forward declare AccelState and AccelClass.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250703173248.44995-39-philmd@linaro.org>
2025-07-15 19:34:33 +02:00
Philippe Mathieu-Daudé 05927e9dc9 accel: Rename 'system/accel-ops.h' -> 'accel/accel-cpu-ops.h'
Unfortunately "system/accel-ops.h" handlers are not only
system-specific. For example, the cpu_reset_hold() hook
is part of the vCPU creation, after it is realized.

Mechanical rename to drop 'system' using:

  $ sed -i -e s_system/accel-ops.h_accel/accel-cpu-ops.h_g \
              $(git grep -l system/accel-ops.h)

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250703173248.44995-38-philmd@linaro.org>
2025-07-15 19:34:33 +02:00
Philippe Mathieu-DaudéandMichael S. Tsirkin 749c21cf6d qemu: Convert target_words_bigendian() to TargetInfo API
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250708215320.70426-6-philmd@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-07-15 02:56:39 -04:00
Marc-André Lureau df892b3954 tpm: "qemu -tpmdev help" should return success
Like other "-foo help" CLI, the qemu process should return 0 for
"-tpmdev help".

While touching this, switch to is_help_option() utility function as
suggested by Peter Maydell.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20250707101412.2055581-1-marcandre.lureau@redhat.com>
2025-07-15 10:22:33 +04:00
Daniil TatianinandMichael S. Tsirkin 260f826cf8 softmmu/runstate: add a way to detect force shutdowns
This can be useful for devices that might take too long to shut down
gracefully, but may have a way to shutdown quickly otherwise if needed
or explicitly requested by a force shutdown.

For now we only consider SIGTERM or the QMP quit() command a force
shutdown, since those bypass the guest entirely and are equivalent to
pulling the power plug.

Signed-off-by: Daniil Tatianin <d-tatianin@yandex-team.ru>
Message-Id: <20250609212547.2859224-2-d-tatianin@yandex-team.ru>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-07-14 09:16:40 -04:00
Philippe Mathieu-DaudéandPeter Maydell 677bb509bf system/qdev: Remove pointless NULL check in qdev_device_add_from_qdict
Coverity reported a unnecessary NULL check:

  qemu/system/qdev-monitor.c: 720 in qdev_device_add_from_qdict()
  683     /* create device */
  684     dev = qdev_new(driver);
  ...
  719     err_del_dev:
  >>>     CID 1590192:  Null pointer dereferences  (REVERSE_INULL)
  >>>     Null-checking "dev" suggests that it may be null, but it has already been dereferenced on all paths leading to the check.
  720         if (dev) {
  721             object_unparent(OBJECT(dev));
  722             object_unref(OBJECT(dev));
  723         }
  724         return NULL;
  725     }

Indeed, unlike qdev_try_new() which can return NULL,
qdev_new() always returns a heap pointer (or aborts).

Remove the unnecessary assignment and check.

Fixes: f3a8505656 ("qdev/qbus: add hidden device support")
Resolves: Coverity CID 1590192 (Null pointer dereferences)
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2025-07-10 16:18:43 +01:00