Commit Graph

243 Commits

Author SHA1 Message Date
Vitaly Kuznetsov
d3177e2e43 target/i386: Make sure SynIC state is really updated before KVM_RUN
'hyperv_synic' test from KVM unittests was observed to be flaky on certain
hardware (hangs sometimes). Debugging shows that the problem happens in
hyperv_sint_route_new() when the test tries to set up a new SynIC
route. The function bails out on:

 if (!synic->sctl_enabled) {
         goto cleanup;
 }

but the test writes to HV_X64_MSR_SCONTROL just before it starts
establishing SINT routes. Further investigation shows that
synic_update() (called from async_synic_update()) happens after the SINT
setup attempt and not before. Apparently, the comment before
async_safe_run_on_cpu() in kvm_hv_handle_exit() does not correctly describe
the guarantees async_safe_run_on_cpu() gives. In particular, async worked
added to a CPU is actually processed from qemu_wait_io_event() which is not
always called before KVM_RUN, i.e. kvm_cpu_exec() checks whether an exit
request is pending for a CPU and if not, keeps running the vCPU until it
meets an exit it can't handle internally. Hyper-V specific MSR writes are
not automatically trigger an exit.

Fix the issue by simply raising an exit request for the vCPU where SynIC
update was queued. This is not a performance critical path as SynIC state
does not get updated so often (and async_safe_run_on_cpu() is a big hammer
anyways).

Reported-by: Jan Richter <jarichte@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240917160051.2637594-4-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-17 12:30:21 +02:00
Vitaly Kuznetsov
7d7b9c7655 target/i386: Exclude 'hv-syndbg' from 'hv-passthrough'
Windows with Hyper-V role enabled doesn't boot with 'hv-passthrough' when
no debugger is configured, this significantly limits the usefulness of the
feature as there's no support for subtracting Hyper-V features from CPU
flags at this moment (e.g. "-cpu host,hv-passthrough,-hv-syndbg" does not
work). While this is also theoretically fixable, 'hv-syndbg' is likely
very special and unneeded in the default set. Genuine Hyper-V doesn't seem
to enable it either.

Introduce 'skip_passthrough' flag to 'kvm_hyperv_properties' and use it as
one-off to skip 'hv-syndbg' when enabling features in 'hv-passthrough'
mode. Note, "-cpu host,hv-passthrough,hv-syndbg" can still be used if
needed.

As both 'hv-passthrough' and 'hv-syndbg' are debug features, the change
should not have any effect on production environments.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240917160051.2637594-3-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-17 12:30:21 +02:00
Vitaly Kuznetsov
bbf3810f2c target/i386: Fix conditional CONFIG_SYNDBG enablement
Putting HYPERV_FEAT_SYNDBG entry under "#ifdef CONFIG_SYNDBG" in
'kvm_hyperv_properties' array is wrong: as HYPERV_FEAT_SYNDBG is not
the highest feature number, the result is an empty (zeroed) entry in
the array (and not a skipped entry!). hyperv_feature_supported() is
designed to check that all CPUID bits are set but for a zeroed
feature in 'kvm_hyperv_properties' it returns 'true' so QEMU considers
HYPERV_FEAT_SYNDBG as always supported, regardless of whether KVM host
actually supports it.

To fix the issue, leave HYPERV_FEAT_SYNDBG's definition in
'kvm_hyperv_properties' array, there's nothing wrong in having it defined
even when 'CONFIG_SYNDBG' is not set. Instead, put "hv-syndbg" CPU property
under '#ifdef CONFIG_SYNDBG' to alter the existing behavior when the flag
is silently skipped in !CONFIG_SYNDBG builds.

Leave an 'assert' sentinel in hyperv_feature_supported() making sure there
are no 'holes' or improperly defined features in 'kvm_hyperv_properties'.

Fixes: d8701185f4 ("hw: hyperv: Initial commit for Synthetic Debugging device")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240917160051.2637594-2-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-17 12:30:21 +02:00
Gao Shiyuan
b5151ace58 target/i386: Add support save/load HWCR MSR
KVM commit 191c8137a939 ("x86/kvm: Implement HWCR support")
introduced support for emulating HWCR MSR.

Add support for QEMU to save/load this MSR for migration purposes.

Signed-off-by: Gao Shiyuan <gaoshiyuan@baidu.com>
Signed-off-by: Wang Liang <wangliang44@baidu.com>
Link: https://lore.kernel.org/r/20241009095109.66843-1-gaoshiyuan@baidu.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-17 12:30:21 +02:00
Xiaoyao Li
5ab639141b target/i386: Construct CPUID 2 as stateful iff times > 1
When times == 1, the CPUID leaf 2 is not stateful.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20240814075431.339209-6-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-17 12:30:21 +02:00
Xiaoyao Li
00c8a933d9 target/i386: Don't construct a all-zero entry for CPUID[0xD 0x3f]
Currently, QEMU always constructs a all-zero CPUID entry for
CPUID[0xD 0x3f].

It's meaningless to construct such a leaf as the end of leaf 0xD. Rework
the logic of how subleaves of 0xD are constructed to get rid of such
all-zero value of subleaf 0x3f.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20240814075431.339209-2-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-17 12:30:20 +02:00
Julia Suvorova
fc058618d1 target/i386/kvm: Report which action failed in kvm_arch_put/get_registers
To help debug and triage future failure reports (akin to [1,2]) that
may occur during kvm_arch_put/get_registers, the error path of each
action is accompanied by unique error message.

[1] https://issues.redhat.com/browse/RHEL-7558
[2] https://issues.redhat.com/browse/RHEL-21761

Signed-off-by: Julia Suvorova <jusual@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240927104743.218468-3-jusual@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-03 22:04:24 +02:00
Julia Suvorova
a1676bb304 kvm: Allow kvm_arch_get/put_registers to accept Error**
This is necessary to provide discernible error messages to the caller.

Signed-off-by: Julia Suvorova <jusual@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240927104743.218468-2-jusual@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-03 22:04:19 +02:00
Paolo Bonzini
dc44854978 kvm/i386: replace identity_base variable with a constant
identity_base variable is first initialzied to address 0xfffbc000 and then
kvm_vm_set_identity_map_addr() overrides this value to address 0xfeffc000.
The initial address to which the variable was initialized was never used. Clean
everything up, placing 0xfeffc000 in a preprocessor constant.

Reported-by: Ani Sinha <anisinha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-03 19:33:23 +02:00
Ani Sinha
0cc42e63bb kvm/i386: refactor kvm_arch_init and split it into smaller functions
kvm_arch_init() enables a lot of vm capabilities. Refactor them into separate
smaller functions. Energy MSR related operations also moved to its own
function. There should be no functional impact.

Signed-off-by: Ani Sinha <anisinha@redhat.com>
Link: https://lore.kernel.org/r/20240903124143.39345-2-anisinha@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-03 19:33:22 +02:00
Ani Sinha
87e82951c1 kvm/i386: fix return values of is_host_cpu_intel()
is_host_cpu_intel() should return TRUE if the host cpu in Intel based, otherwise
it should return FALSE. Currently, it returns zero (FALSE) when the host CPU
is INTEL and non-zero otherwise. Fix the function so that it agrees more with
the semantics. Adjust the calling logic accordingly. RAPL needs Intel host cpus.
If the host CPU is not Intel baseed, we should report error.

Signed-off-by: Ani Sinha <anisinha@redhat.com>
Link: https://lore.kernel.org/r/20240903080004.33746-1-anisinha@redhat.com
[While touching the code remove too many spaces from the second part of the
 error. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-02 12:58:46 +02:00
Ani Sinha
ed2880f4e9 kvm/i386: make kvm_filter_msr() and related definitions private to kvm module
kvm_filer_msr() is only used from i386 kvm module. Make it static so that its
easy for developers to understand that its not used anywhere else.
Same for QEMURDMSRHandler, QEMUWRMSRHandler and KVMMSRHandlers definitions.

CC: philmd@linaro.org
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Ani Sinha <anisinha@redhat.com>
Link: https://lore.kernel.org/r/20240903140045.41167-1-anisinha@redhat.com
[Make struct unnamed. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-02 12:58:46 +02:00
Lei Wang
ab891454eb target/i386: Raise the highest index value used for any VMCS encoding
Because the index value of the VMCS field encoding of FRED injected-event
data (one of the newly added VMCS fields for FRED transitions), 0x52, is
larger than any existing index value, raise the highest index value used
for any VMCS encoding to 0x52.

Because the index value of the VMCS field encoding of Secondary VM-exit
controls, 0x44, is larger than any existing index value, raise the highest
index value used for any VMCS encoding to 0x44.

Co-developed-by: Xin Li <xin3.li@intel.com>
Signed-off-by: Xin Li <xin3.li@intel.com>
Signed-off-by: Lei Wang <lei4.wang@intel.com>
Signed-off-by: Xin Li (Intel) <xin@zytor.com>
Link: https://lore.kernel.org/r/20240807081813.735158-4-xin@zytor.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-02 12:58:46 +02:00
Pierrick Bouvier
f4fa1a5350 target/i386/kvm: replace assert(false) with g_assert_not_reached()
This patch is part of a series that moves towards a consistent use of
g_assert_not_reached() rather than an ad hoc mix of different
assertion mechanisms.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-ID: <20240919044641.386068-15-pierrick.bouvier@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2024-09-24 13:53:35 +02:00
Johannes Stoelp
6a8703aecb kvm: Use 'unsigned long' for request argument in functions wrapping ioctl()
Change the data type of the ioctl _request_ argument from 'int' to
'unsigned long' for the various accel/kvm functions which are
essentially wrappers around the ioctl() syscall.

The correct type for ioctl()'s 'request' argument is confused:
 * POSIX defines the request argument as 'int'
 * glibc uses 'unsigned long' in the prototype in sys/ioctl.h
 * the glibc info documentation uses 'int'
 * the Linux manpage uses 'unsigned long'
 * the Linux implementation of the syscall uses 'unsigned int'

If we wrap ioctl() with another function which uses 'int' as the
type for the request argument, then requests with the 0x8000_0000
bit set will be sign-extended when the 'int' is cast to
'unsigned long' for the call to ioctl().

On x86_64 one such example is the KVM_IRQ_LINE_STATUS request.
Bit requests with the _IOC_READ direction bit set, will have the high
bit set.

Fortunately the Linux Kernel truncates the upper 32bit of the request
on 64bit machines (because it uses 'unsigned int', and see also Linus
Torvalds' comments in
  https://sourceware.org/bugzilla/show_bug.cgi?id=14362 )
so this doesn't cause active problems for us.  However it is more
consistent to follow the glibc ioctl() prototype when we define
functions that are essentially wrappers around ioctl().

This resolves a Coverity issue where it points out that in
kvm_get_xsave() we assign a value (KVM_GET_XSAVE or KVM_GET_XSAVE2)
to an 'int' variable which can't hold it without overflow.

Resolves: Coverity CID 1547759
Signed-off-by: Johannes Stoelp <johannes.stoelp@gmail.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20240815122747.3053871-1-peter.maydell@linaro.org
[PMM: Rebased patch, adjusted commit message, included note about
 Coverity fix, updated the type of the local var in kvm_get_xsave,
 updated the comment in the KVMState struct definition]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2024-09-13 15:31:46 +01:00
Anthony Harivel
a6e65975c3 target/i386: Fix arguments for vmsr_read_thread_stat()
Snapshot of the stat utime and stime for each thread, taken before and
after the pause, must be stored in separate locations

Signed-off-by: Anthony Harivel <aharivel@redhat.com>
Link: https://lore.kernel.org/r/20240807124320.1741124-2-aharivel@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-08-14 18:42:19 +02:00
Anthony Harivel
6e623af301 target/i386: Clean up error cases for vmsr_read_thread_stat()
Fix leaking memory of file handle in case of error
Erase unused "pid = -1"
Add clearer error_report

Should fix Coverity CID 1558557.

Signed-off-by: Anthony Harivel <aharivel@redhat.com>
Link: https://lore.kernel.org/r/20240726102632.1324432-3-aharivel@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-07-31 13:13:31 +02:00
Anthony Harivel
5997fbdfac target/i386: Fix typo that assign same value twice
Should fix: CID 1558553

Signed-off-by: Anthony Harivel <aharivel@redhat.com>
Link: https://lore.kernel.org/r/20240726102632.1324432-2-aharivel@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-07-31 13:13:31 +02:00
Anthony Harivel
0418f90809 Add support for RAPL MSRs in KVM/Qemu
Starting with the "Sandy Bridge" generation, Intel CPUs provide a RAPL
interface (Running Average Power Limit) for advertising the accumulated
energy consumption of various power domains (e.g. CPU packages, DRAM,
etc.).

The consumption is reported via MSRs (model specific registers) like
MSR_PKG_ENERGY_STATUS for the CPU package power domain. These MSRs are
64 bits registers that represent the accumulated energy consumption in
micro Joules. They are updated by microcode every ~1ms.

For now, KVM always returns 0 when the guest requests the value of
these MSRs. Use the KVM MSR filtering mechanism to allow QEMU handle
these MSRs dynamically in userspace.

To limit the amount of system calls for every MSR call, create a new
thread in QEMU that updates the "virtual" MSR values asynchronously.

Each vCPU has its own vMSR to reflect the independence of vCPUs. The
thread updates the vMSR values with the ratio of energy consumed of
the whole physical CPU package the vCPU thread runs on and the
thread's utime and stime values.

All other non-vCPU threads are also taken into account. Their energy
consumption is evenly distributed among all vCPUs threads running on
the same physical CPU package.

To overcome the problem that reading the RAPL MSR requires priviliged
access, a socket communication between QEMU and the qemu-vmsr-helper is
mandatory. You can specified the socket path in the parameter.

This feature is activated with -accel kvm,rapl=true,path=/path/sock.sock

Actual limitation:
- Works only on Intel host CPU because AMD CPUs are using different MSR
  adresses.

- Only the Package Power-Plane (MSR_PKG_ENERGY_STATUS) is reported at
  the moment.

Signed-off-by: Anthony Harivel <aharivel@redhat.com>
Link: https://lore.kernel.org/r/20240522153453.1230389-4-aharivel@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-07-22 19:19:37 +02:00
Richard Henderson
5915139aba * meson: Pass objects and dependencies to declare_dependency(), not static_library()
* meson: Drop the .fa library suffix
 * target/i386: drop AMD machine check bits from Intel CPUID
 * target/i386: add avx-vnni-int16 feature
 * target/i386: SEV bugfixes
 * target/i386: SEV-SNP -cpu host support
 * char: fix exit issues
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Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into staging

* meson: Pass objects and dependencies to declare_dependency(), not static_library()
* meson: Drop the .fa library suffix
* target/i386: drop AMD machine check bits from Intel CPUID
* target/i386: add avx-vnni-int16 feature
* target/i386: SEV bugfixes
* target/i386: SEV-SNP -cpu host support
* char: fix exit issues

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# gpg: Signature made Thu 04 Jul 2024 02:56:58 AM PDT
# gpg:                using RSA key F13338574B662389866C7682BFFBD25F78C7AE83
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# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [full]
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>" [full]

* tag 'for-upstream' of https://gitlab.com/bonzini/qemu:
  target/i386/SEV: implement mask_cpuid_features
  target/i386: add support for masking CPUID features in confidential guests
  char-stdio: Restore blocking mode of stdout on exit
  target/i386: add avx-vnni-int16 feature
  i386/sev: Fallback to the default SEV device if none provided in sev_get_capabilities()
  i386/sev: Fix error message in sev_get_capabilities()
  target/i386: do not include undefined bits in the AMD topoext leaf
  target/i386: SEV: fix formatting of CPUID mismatch message
  target/i386: drop AMD machine check bits from Intel CPUID
  target/i386: pass X86CPU to x86_cpu_get_supported_feature_word
  meson: Drop the .fa library suffix
  Revert "meson: Propagate gnutls dependency"
  meson: Pass objects and dependencies to declare_dependency()
  meson: merge plugin_ldflags into emulator_link_args
  meson: move block.syms dependency out of libblock
  meson: move shared_module() calls where modules are already walked

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-07-04 09:16:07 -07:00
Paolo Bonzini
c28d8b097f target/i386: add support for masking CPUID features in confidential guests
Some CPUID features may be provided by KVM for some guests, independent of
processor support, for example TSC deadline or TSC adjust.  If these are
not supported by the confidential computing firmware, however, the guest
will fail to start.  Add support for removing unsupported features from
"-cpu host".

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-07-04 07:47:11 +02:00
David Woodhouse
93c76555d8 hw/i386/fw_cfg: Add etc/e820 to fw_cfg late
In e820_add_entry() the e820_table is reallocated with g_renew() to make
space for a new entry. However, fw_cfg_arch_create() just uses the
existing e820_table pointer. This leads to a use-after-free if anything
adds a new entry after fw_cfg is set up.

Shift the addition of the etc/e820 file to the machine done notifier, via
a new fw_cfg_add_e820() function.

Also make e820_table private and use an e820_get_table() accessor function
for it, which sets a flag that will trigger an assert() for any *later*
attempts to add to the table.

Make e820_add_entry() return void, as most callers don't check for error
anyway.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <a2708734f004b224f33d3b4824e9a5a262431568.camel@infradead.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2024-07-03 18:14:06 -04:00
Paolo Bonzini
8dee384832 target/i386: pass X86CPU to x86_cpu_get_supported_feature_word
This allows modifying the bits in "-cpu max"/"-cpu host" depending on
the guest CPU vendor (which, at least by default, is the host vendor in
the case of KVM).

For example, machine check architecture differs between Intel and AMD,
and bits from AMD should be dropped when configuring the guest for
an Intel model.

Cc: Xiaoyao Li <xiaoyao.li@intel.com>
Cc: John Allen <john.allen@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-07-03 18:41:26 +02:00
Zide Chen
05fc711c3a target/i386: Advertise MWAIT iff host supports
host_cpu_realizefn() sets CPUID_EXT_MONITOR without consulting host/KVM
capabilities. This may cause problems:

- If MWAIT/MONITOR is not available on the host, advertising this
  feature to the guest and executing MWAIT/MONITOR from the guest
  triggers #UD and the guest doesn't boot.  This is because typically
  #UD takes priority over VM-Exit interception checks and KVM doesn't
  emulate MONITOR/MWAIT on #UD.

- If KVM doesn't support KVM_X86_DISABLE_EXITS_MWAIT, MWAIT/MONITOR
  from the guest are intercepted by KVM, which is not what cpu-pm=on
  intends to do.

In these cases, MWAIT/MONITOR should not be exposed to the guest.

The logic in kvm_arch_get_supported_cpuid() to handle CPUID_EXT_MONITOR
is correct and sufficient, and we can't set CPUID_EXT_MONITOR after
x86_cpu_filter_features().

This was not an issue before commit 662175b91f ("i386: reorder call to
cpu_exec_realizefn") because the feature added in the accel-specific
realizefn could be checked against host availability and filtered out.

Additionally, it seems not a good idea to handle guest CPUID leaves in
host_cpu_realizefn(), and this patch merges host_cpu_enable_cpu_pm()
into kvm_cpu_realizefn().

Fixes: f5cc5a5c16 ("i386: split cpu accelerators from cpu.c, using AccelCPUClass")
Fixes: 662175b91f ("i386: reorder call to cpu_exec_realizefn")
Signed-off-by: Zide Chen <zide.chen@intel.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2024-06-30 19:51:44 +03:00
Alex Bennée
5b7d54d4ed gdbstub: move enums into separate header
This is an experiment to further reduce the amount we throw into the
exec headers. It might not be as useful as I initially thought because
just under half of the users also need gdbserver_start().

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240620152220.2192768-3-alex.bennee@linaro.org>
2024-06-24 10:14:17 +01:00
Philippe Mathieu-Daudé
8291239113 target/i386: Remove X86CPU::kvm_no_smi_migration field
X86CPU::kvm_no_smi_migration was only used by the
pc-i440fx-2.3 machine, which got removed. Remove it
and simplify kvm_put_vcpu_events().

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20240617071118.60464-23-philmd@linaro.org>
2024-06-19 12:40:49 +02:00
Philippe Mathieu-Daudé
63f16d97c6 target/i386/kvm: Remove x86_cpu_change_kvm_default() and 'kvm-cpu.h'
x86_cpu_change_kvm_default() was only used out of kvm-cpu.c by
the pc-i440fx-2.1 machine, which got removed. Make it static,
and remove its declaration. "kvm-cpu.h" is now empty, remove it.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20240617071118.60464-10-philmd@linaro.org>
2024-06-19 12:40:49 +02:00
John Allen
1ea1432199 i386: Add support for overflow recovery
Add cpuid bit definition for overflow recovery. This is needed in the case
where a deferred error has been sent to the guest, a guest process accesses the
poisoned memory, but the machine_check_poll function has not yet handled the
original deferred error. If overflow recovery is not set in this case, when we
handle the uncorrected error from the poisoned memory access, the overflow bit
will be set and will result in the guest being shut down.

By the time the MCE reaches the guest, the overflow has been handled
by the host and has not caused a shutdown, so include the bit unconditionally.

Signed-off-by: John Allen <john.allen@amd.com>
Message-ID: <20240603193622.47156-4-john.allen@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-06-08 10:33:39 +02:00
John Allen
2ba8b7ee63 i386: Add support for SUCCOR feature
Add cpuid bit definition for the SUCCOR feature. This cpuid bit is required to
be exposed to guests to allow them to handle machine check exceptions on AMD
hosts.

----
v2:
  - Add "succor" feature word.
  - Add case to kvm_arch_get_supported_cpuid for the SUCCOR feature.

Reported-by: William Roche <william.roche@oracle.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: John Allen <john.allen@amd.com>
Message-ID: <20240603193622.47156-3-john.allen@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-06-08 10:33:39 +02:00
John Allen
4b77512b27 i386: Fix MCE support for AMD hosts
For the most part, AMD hosts can use the same MCE injection code as Intel, but
there are instances where the qemu implementation is Intel specific. First, MCE
delivery works differently on AMD and does not support broadcast. Second,
kvm_mce_inject generates MCEs that include a number of Intel specific status
bits. Modify kvm_mce_inject to properly generate MCEs on AMD platforms.

Reported-by: William Roche <william.roche@oracle.com>
Signed-off-by: John Allen <john.allen@amd.com>
Message-ID: <20240603193622.47156-2-john.allen@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-06-08 10:33:38 +02:00
Xin Li
4ebd98eb3a target/i386: Add get/set/migrate support for FRED MSRs
FRED CPU states are managed in 9 new FRED MSRs, in addtion to a few
existing CPU registers and MSRs, e.g., CR4.FRED and MSR_IA32_PL0_SSP.

Save/restore/migrate FRED MSRs if FRED is exposed to the guest.

Tested-by: Shan Kang <shan.kang@intel.com>
Signed-off-by: Xin Li <xin3.li@intel.com>
Message-ID: <20231109072012.8078-7-xin3.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-06-08 10:33:38 +02:00
Richard Henderson
f1572ab947 * virtio-blk: remove SCSI passthrough functionality
* require x86-64-v2 baseline ISA
 * SEV-SNP host support
 * fix xsave.flat with TCG
 * fixes for CPUID checks done by TCG
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Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into staging

* virtio-blk: remove SCSI passthrough functionality
* require x86-64-v2 baseline ISA
* SEV-SNP host support
* fix xsave.flat with TCG
* fixes for CPUID checks done by TCG

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# gpg: Signature made Wed 05 Jun 2024 02:01:10 AM PDT
# 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]

* tag 'for-upstream' of https://gitlab.com/bonzini/qemu: (46 commits)
  hw/i386: Add support for loading BIOS using guest_memfd
  hw/i386/sev: Use guest_memfd for legacy ROMs
  memory: Introduce memory_region_init_ram_guest_memfd()
  i386/sev: Allow measured direct kernel boot on SNP
  i386/sev: Reorder struct declarations
  i386/sev: Extract build_kernel_loader_hashes
  i386/sev: Enable KVM_HC_MAP_GPA_RANGE hcall for SNP guests
  i386/kvm: Add KVM_EXIT_HYPERCALL handling for KVM_HC_MAP_GPA_RANGE
  i386/sev: Invoke launch_updata_data() for SNP class
  i386/sev: Invoke launch_updata_data() for SEV class
  hw/i386/sev: Add support to encrypt BIOS when SEV-SNP is enabled
  i386/sev: Add support for SNP CPUID validation
  i386/sev: Add support for populating OVMF metadata pages
  hw/i386/sev: Add function to get SEV metadata from OVMF header
  i386/sev: Set CPU state to protected once SNP guest payload is finalized
  i386/sev: Add handling to encrypt/finalize guest launch data
  i386/sev: Add the SNP launch start context
  i386/sev: Update query-sev QAPI format to handle SEV-SNP
  i386/sev: Add a class method to determine KVM VM type for SNP guests
  i386/sev: Don't return launch measurements for SEV-SNP guests
  ...

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-06-05 07:45:23 -07:00
Michael Roth
47e76d03b1 i386/kvm: Add KVM_EXIT_HYPERCALL handling for KVM_HC_MAP_GPA_RANGE
KVM_HC_MAP_GPA_RANGE will be used to send requests to userspace for
private/shared memory attribute updates requested by the guest.
Implement handling for that use-case along with some basic
infrastructure for enabling specific hypercall events.

Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Pankaj Gupta <pankaj.gupta@amd.com>
Message-ID: <20240530111643.1091816-31-pankaj.gupta@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-06-05 11:01:06 +02:00
Paolo Bonzini
a808132f6d i386/sev: Add a class method to determine KVM VM type for SNP guests
SEV guests can use either KVM_X86_DEFAULT_VM, KVM_X86_SEV_VM,
or KVM_X86_SEV_ES_VM depending on the configuration and what
the host kernel supports. SNP guests on the other hand can only
ever use KVM_X86_SNP_VM, so split determination of VM type out
into a separate class method that can be set accordingly for
sev-guest vs. sev-snp-guest objects and add handling for SNP.

Signed-off-by: Pankaj Gupta <pankaj.gupta@amd.com>
Message-ID: <20240530111643.1091816-14-pankaj.gupta@amd.com>
[Remove unnecessary function pointer declaration. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-06-05 11:01:06 +02:00
Richard Henderson
a93b4061b0 target/i386/kvm: Improve KVM_EXIT_NOTIFY warnings
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Message-ID: <20240412073346.458116-28-richard.henderson@linaro.org>
[PMD: Fixed typo reported by Peter Maydell]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2024-06-04 10:02:39 +02:00
donsheng
84d4b72854 target-i386: hyper-v: Correct kvm_hv_handle_exit return value
This bug fix addresses the incorrect return value of kvm_hv_handle_exit for
KVM_EXIT_HYPERV_SYNIC, which should be EXCP_INTERRUPT.

Handling of KVM_EXIT_HYPERV_SYNIC in QEMU needs to be synchronous.
This means that async_synic_update should run in the current QEMU vCPU
thread before returning to KVM, returning EXCP_INTERRUPT to guarantee this.
Returning 0 can cause async_synic_update to run asynchronously.

One problem (kvm-unit-tests's hyperv_synic test fails with timeout error)
caused by this bug:

When a guest VM writes to the HV_X64_MSR_SCONTROL MSR to enable Hyper-V SynIC,
a VM exit is triggered and processed by the kvm_hv_handle_exit function of the
QEMU vCPU. This function then calls the async_synic_update function to set
synic->sctl_enabled to true. A true value of synic->sctl_enabled is required
before creating SINT routes using the hyperv_sint_route_new() function.

If kvm_hv_handle_exit returns 0 for KVM_EXIT_HYPERV_SYNIC, the current QEMU
vCPU thread may return to KVM and enter the guest VM before running
async_synic_update. In such case, the hyperv_synic test’s subsequent call to
synic_ctl(HV_TEST_DEV_SINT_ROUTE_CREATE, ...) immediately after writing to
HV_X64_MSR_SCONTROL can cause QEMU’s hyperv_sint_route_new() function to return
prematurely (because synic->sctl_enabled is false).

If the SINT route is not created successfully, the SINT interrupt will not be
fired, resulting in a timeout error in the hyperv_synic test.

Fixes: 267e071bd6 (“hyperv: make overlay pages for SynIC”)
Suggested-by: Chao Gao <chao.gao@intel.com>
Signed-off-by: Dongsheng Zhang <dongsheng.x.zhang@intel.com>
Message-ID: <20240521200114.11588-1-dongsheng.x.zhang@intel.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-05-22 19:56:28 +02:00
Zhao Liu
6ddeb0ec8c i386/cpu: Introduce bitmap to cache available CPU topology levels
Currently, QEMU checks the specify number of topology domains to detect
if there's extended topology levels (e.g., checking nr_dies).

With this bitmap, the extended CPU topology (the levels other than SMT,
core and package) could be easier to detect without touching the
topology details.

This is also in preparation for the follow-up to decouple CPUID[0x1F]
subleaf with specific topology level.

Tested-by: Yongwei Ma <yongwei.ma@intel.com>
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-ID: <20240424154929.1487382-10-zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-05-22 19:43:29 +02:00
Paolo Bonzini
663e2f443e target/i386: SEV: use KVM_SEV_INIT2 if possible
Implement support for the KVM_X86_SEV_VM and KVM_X86_SEV_ES_VM virtual
machine types, and the KVM_SEV_INIT2 function of KVM_MEMORY_ENCRYPT_OP.

These replace the KVM_SEV_INIT and KVM_SEV_ES_INIT functions, and have
several advantages:

- sharing the initialization sequence with SEV-SNP and TDX

- allowing arguments including the set of desired VMSA features

- protection against invalid use of KVM_GET/SET_* ioctls for guests
  with encrypted state

If the KVM_X86_SEV_VM and KVM_X86_SEV_ES_VM types are not supported,
fall back to KVM_SEV_INIT and KVM_SEV_ES_INIT (which use the
default x86 VM type).

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-04-23 17:35:25 +02:00
Paolo Bonzini
ee88612df1 target/i386: Implement mc->kvm_type() to get VM type
KVM is introducing a new API to create confidential guests, which
will be used by TDX and SEV-SNP but is also available for SEV and
SEV-ES.  The API uses the VM type argument to KVM_CREATE_VM to
identify which confidential computing technology to use.

Since there are no other expected uses of VM types, delegate
mc->kvm_type() for x86 boards to the confidential-guest-support
object pointed to by ms->cgs.

For example, if a sev-guest object is specified to confidential-guest-support,
like,

  qemu -machine ...,confidential-guest-support=sev0 \
       -object sev-guest,id=sev0,...

it will check if a VM type KVM_X86_SEV_VM or KVM_X86_SEV_ES_VM
is supported, and if so use them together with the KVM_SEV_INIT2
function of the KVM_MEMORY_ENCRYPT_OP ioctl. If not, it will fall back to
KVM_SEV_INIT and KVM_SEV_ES_INIT.

This is a preparatory work towards TDX and SEV-SNP support, but it
will also enable support for VMSA features such as DebugSwap, which
are only available via KVM_SEV_INIT2.

Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-04-23 17:35:25 +02:00
Paolo Bonzini
a99c0c66eb KVM: remove kvm_arch_cpu_check_are_resettable
Board reset requires writing a fresh CPU state.  As far as KVM is
concerned, the only thing that blocks reset is that CPU state is
encrypted; therefore, kvm_cpus_are_resettable() can simply check
if that is the case.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-04-23 17:35:25 +02:00
Xiaoyao Li
637c95b37b i386/sev: Switch to use confidential_guest_kvm_init()
Use confidential_guest_kvm_init() instead of calling SEV
specific sev_kvm_init(). This allows the introduction of multiple
confidential-guest-support subclasses for different x86 vendors.

As a bonus, stubs are not needed anymore since there is no
direct call from target/i386/kvm/kvm.c to SEV code.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20240229060038.606591-1-xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-04-23 17:35:25 +02:00
Sean Christopherson
a5acf4f26c i386/kvm: Move architectural CPUID leaf generation to separate helper
Move the architectural (for lack of a better term) CPUID leaf generation
to a separate helper so that the generation code can be reused by TDX,
which needs to generate a canonical VM-scoped configuration.

For now this is just a cleanup, so keep the function static.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-ID: <20240229063726.610065-23-xiaoyao.li@intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-04-23 17:35:13 +02:00
Gerd Hoffmann
0d08c42368 kvm: add support for guest physical bits
Query kvm for supported guest physical address bits, in cpuid
function 80000008, eax[23:16].  Usually this is identical to host
physical address bits.  With NPT or EPT being used this might be
restricted to 48 (max 4-level paging address space size) even if
the host cpu supports more physical address bits.

When set pass this to the guest, using cpuid too.  Guest firmware
can use this to figure how big the usable guest physical address
space is, so PCI bar mapping are actually reachable.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Message-ID: <20240318155336.156197-2-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-04-18 11:17:28 +02:00
Maciej S. Szmigiero
6093637b4d vmbus: Print a warning when enabled without the recommended set of features
Some Windows versions crash at boot or fail to enable the VMBus device if
they don't see the expected set of Hyper-V features (enlightenments).

Since this provides poor user experience let's warn user if the VMBus
device is enabled without the recommended set of Hyper-V features.

The recommended set is the minimum set of Hyper-V features required to make
the VMBus device work properly in Windows Server versions 2016, 2019 and
2022.

Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
2024-03-08 14:18:56 +01:00
Xiaoyao Li
0729857c70 i386/cpuid: Move leaf 7 to correct group
CPUID leaf 7 was grouped together with SGX leaf 0x12 by commit
b9edbadefb ("i386: Propagate SGX CPUID sub-leafs to KVM") by mistake.

SGX leaf 0x12 has its specific logic to check if subleaf (starting from 2)
is valid or not by checking the bit 0:3 of corresponding EAX is 1 or
not.

Leaf 7 follows the logic that EAX of subleaf 0 enumerates the maximum
valid subleaf.

Fixes: b9edbadefb ("i386: Propagate SGX CPUID sub-leafs to KVM")
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-ID: <20240125024016.2521244-4-xiaoyao.li@intel.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-02-16 13:56:08 +01:00
Xiaoyao Li
a3b5376521 i386/cpuid: Remove subleaf constraint on CPUID leaf 1F
No such constraint that subleaf index needs to be less than 64.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by:Yang Weijiang <weijiang.yang@intel.com>
Message-ID: <20240125024016.2521244-3-xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-02-16 13:56:08 +01:00
Xiaoyao Li
10f92799af i386/cpuid: Decrease cpuid_i when skipping CPUID leaf 1F
Existing code misses a decrement of cpuid_i when skip leaf 0x1F.
There's a blank CPUID entry(with leaf, subleaf as 0, and all fields
stuffed 0s) left in the CPUID array.

It conflicts with correct CPUID leaf 0.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by:Yang Weijiang <weijiang.yang@intel.com>
Message-ID: <20240125024016.2521244-2-xiaoyao.li@intel.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-02-16 13:56:08 +01:00
Stefan Hajnoczi
32ead8e62f qemu/main-loop: rename QEMU_IOTHREAD_LOCK_GUARD to BQL_LOCK_GUARD
The name "iothread" is overloaded. Use the term Big QEMU Lock (BQL)
instead, it is already widely used and unambiguous.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20240102153529.486531-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2024-01-08 10:45:43 -05:00
Stefan Hajnoczi
195801d700 system/cpus: rename qemu_mutex_lock_iothread() to bql_lock()
The Big QEMU Lock (BQL) has many names and they are confusing. The
actual QemuMutex variable is called qemu_global_mutex but it's commonly
referred to as the BQL in discussions and some code comments. The
locking APIs, however, are called qemu_mutex_lock_iothread() and
qemu_mutex_unlock_iothread().

The "iothread" name is historic and comes from when the main thread was
split into into KVM vcpu threads and the "iothread" (now called the main
loop thread). I have contributed to the confusion myself by introducing
a separate --object iothread, a separate concept unrelated to the BQL.

The "iothread" name is no longer appropriate for the BQL. Rename the
locking APIs to:
- void bql_lock(void)
- void bql_unlock(void)
- bool bql_locked(void)

There are more APIs with "iothread" in their names. Subsequent patches
will rename them. There are also comments and documentation that will be
updated in later patches.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: Fabiano Rosas <farosas@suse.de>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Peter Xu <peterx@redhat.com>
Acked-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Acked-by: Hyman Huang <yong.huang@smartx.com>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20240102153529.486531-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2024-01-08 10:45:43 -05:00
Michael Roth
5746f70d68 i386/sev: Avoid SEV-ES crash due to missing MSR_EFER_LMA bit
Commit 7191f24c7f ("accel/kvm/kvm-all: Handle register access errors")
added error checking for KVM_SET_SREGS/KVM_SET_SREGS2. In doing so, it
exposed a long-running bug in current KVM support for SEV-ES where the
kernel assumes that MSR_EFER_LMA will be set explicitly by the guest
kernel, in which case EFER write traps would result in KVM eventually
seeing MSR_EFER_LMA get set and recording it in such a way that it would
be subsequently visible when accessing it via KVM_GET_SREGS/etc.

However, guest kernels currently rely on MSR_EFER_LMA getting set
automatically when MSR_EFER_LME is set and paging is enabled via
CR0_PG_MASK. As a result, the EFER write traps don't actually expose the
MSR_EFER_LMA bit, even though it is set internally, and when QEMU
subsequently tries to pass this EFER value back to KVM via
KVM_SET_SREGS* it will fail various sanity checks and return -EINVAL,
which is now considered fatal due to the aforementioned QEMU commit.

This can be addressed by inferring the MSR_EFER_LMA bit being set when
paging is enabled and MSR_EFER_LME is set, and synthesizing it to ensure
the expected bits are all present in subsequent handling on the host
side.

Ultimately, this handling will be implemented in the host kernel, but to
avoid breaking QEMU's SEV-ES support when using older host kernels, the
same handling can be done in QEMU just after fetching the register
values via KVM_GET_SREGS*. Implement that here.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Akihiko Odaki <akihiko.odaki@daynix.com>
Cc: Philippe Mathieu-Daudé <philmd@linaro.org>
Cc: Lara Lazier <laramglazier@gmail.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Cc:  <kvm@vger.kernel.org>
Fixes: 7191f24c7f ("accel/kvm/kvm-all: Handle register access errors")
Signed-off-by: Michael Roth <michael.roth@amd.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20231206155821.1194551-1-michael.roth@amd.com>
2023-12-06 14:34:11 -05:00