Allows SYNDBG definitions to be available for common compilation units.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-ID: <20250307215623.524987-5-pierrick.bouvier@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
AccelCPUClass is for accelerator to initialize target specific
features of a vCPU. Not really related to hardware emulation,
rename "hw/core/accel-cpu.h" as "accel/accel-cpu-target.h"
(using the explicit -target suffix).
More importantly, target specific header often access the
target specific definitions which are in each target/FOO/cpu.h
header, usually included generically as "cpu.h" relative to
target/FOO/. However, there is already a "cpu.h" in hw/core/
which takes precedence. This change allows "accel-cpu-target.h"
to include a target "cpu.h".
Mechanical change doing:
$ git mv include/hw/core/accel-cpu.h \
include/accel/accel-cpu-target.h
$ sed -i -e 's,hw/core/accel-cpu.h,accel/accel-cpu-target.h,' \
$(git grep -l hw/core/accel-cpu.h)
and renaming header guard 'ACCEL_CPU_TARGET_H'.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250123234415.59850-12-philmd@linaro.org>
There are duplicated code to setup the value of MSR_CORE_THREAD_COUNT.
Extract a common function for it.
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20241219110125.1266461-2-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
kvm_install_msr_filters() uses KVM_MSR_FILTER_MAX_RANGES as the bound
when traversing msr_handlers[], while other places still compute the
size by ARRAY_SIZE(msr_handlers).
In fact, msr_handlers[] is an array with the fixed size
KVM_MSR_FILTER_MAX_RANGES, and this has to be true because
kvm_install_msr_filters copies from one array to the other.
For code consistency, assert that they match and use
ARRAY_SIZE(msr_handlers) everywehere.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, there're following incorrect error handling cases in
kvm_arch_init():
* Missed to handle failure of kvm_get_supported_feature_msrs().
* Missed to return when kvm_vm_enable_disable_exits() fails.
* MSR filter related cases called exit() directly instead of returning
to kvm_init(). (The caller of kvm_arch_init() - kvm_init() - needs to
know if kvm_arch_init() fails in order to perform cleanup).
Fix the above cases.
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Zide Chen <zide.chen@intel.com>
Link: https://lore.kernel.org/r/20241106030728.553238-11-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It is common practice to return a negative value (like -1) to indicate
an error, and other functions in kvm_arch_init() follow this style.
To avoid confusion (sometimes returned -1 indicates failure, and
sometimes -1, in a same function), return -1 when
kvm_msr_energy_thread_init() fails.
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20241106030728.553238-10-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Before commit 0cc42e63bb54 ("kvm/i386: refactor kvm_arch_init and split
it into smaller functions"), error_report() attempts to print the error
code from kvm_filter_msr(). However, printing error code does not work
due to kvm_filter_msr() returns bool instead int.
0cc42e63bb54 fixed the error by removing error code printing, but this
lost useful error messages. Bring it back by making kvm_filter_msr()
return int.
This also makes the function call chain processing clearer, allowing for
better handling of error result propagation from kvm_filter_msr() to
kvm_arch_init(), preparing for the subsequent cleanup work of error
handling in kvm_arch_init().
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Zide Chen <zide.chen@intel.com>
Link: https://lore.kernel.org/r/20241106030728.553238-9-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The KVM_X86_DISABLE_EXITS_HTL typo has been fixed in commit
77d361b13c19 ("linux-headers: Update to kernel mainline commit
b357bf602").
Drop the related workaround.
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Zide Chen <zide.chen@intel.com>
Link: https://lore.kernel.org/r/20241106030728.553238-7-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
MSR_KVM_SYSTEM_TIME and MSR_KVM_WALL_CLOCK are attached with the (old)
kvmclock feature (KVM_FEATURE_CLOCKSOURCE).
So, just save/load them only when kvmclock (KVM_FEATURE_CLOCKSOURCE) is
enabled.
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Zide Chen <zide.chen@intel.com>
Link: https://lore.kernel.org/r/20241106030728.553238-5-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
These 2 MSRs have been already defined in kvm_para.h (standard-headers/
asm-x86/kvm_para.h).
Remove QEMU local definitions to avoid duplication.
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Zide Chen <zide.chen@intel.com>
Link: https://lore.kernel.org/r/20241106030728.553238-4-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add feature definitions for KVM_CPUID_FEATURES in CPUID (
CPUID[4000_0001].EAX and CPUID[4000_0001].EDX), to get rid of lots of
offset calculations.
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Zide Chen <zide.chen@intel.com>
Link: https://lore.kernel.org/r/20241106030728.553238-3-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Since commit 5286c3662294 ("target/i386: properly reset TSC on reset")
QEMU writes the special value of "1" to each online vCPU TSC on VM reset
to reset it.
However parked vCPUs don't get that handling and due to that their TSCs
get desynchronized when the VM gets reset.
This in turn causes KVM to turn off PVCLOCK_TSC_STABLE_BIT in its exported
PV clock.
Note that KVM has no understanding of vCPU being currently parked.
Without PVCLOCK_TSC_STABLE_BIT the sched clock is marked unstable in
the guest's kvm_sched_clock_init().
This causes a performance regressions to show in some tests.
Fix this issue by writing the special value of "1" also to TSCs of parked
vCPUs on VM reset.
Reproducing the issue:
1) Boot a VM with "-smp 2,maxcpus=3" or similar
2) device_add host-x86_64-cpu,id=vcpu,node-id=0,socket-id=0,core-id=2,thread-id=0
3) Wait a few seconds
4) device_del vcpu
5) Inside the VM run:
# echo "t" >/proc/sysrq-trigger; dmesg | grep sched_clock_stable
Observe the sched_clock_stable() value is 1.
6) Reboot the VM
7) Once the VM boots once again run inside it:
# echo "t" >/proc/sysrq-trigger; dmesg | grep sched_clock_stable
Observe the sched_clock_stable() value is now 0.
Fixes: 5286c3662294 ("target/i386: properly reset TSC on reset")
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Link: https://lore.kernel.org/r/5a605a88e9a231386dc803c60f5fed9b48108139.1734014926.git.maciej.szmigiero@oracle.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit 3f2a05b31ee9ce2ddb6c75a9bc3f5e7f7af9a76f)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Headers in include/sysemu/ are not only related to system
*emulation*, they are also used by virtualization. Rename
as system/ which is clearer.
Files renamed manually then mechanical change using sed tool.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Lei Yang <leiyang@redhat.com>
Message-Id: <20241203172445.28576-1-philmd@linaro.org>
Since commit 5286c3662294 ("target/i386: properly reset TSC on reset")
QEMU writes the special value of "1" to each online vCPU TSC on VM reset
to reset it.
However parked vCPUs don't get that handling and due to that their TSCs
get desynchronized when the VM gets reset.
This in turn causes KVM to turn off PVCLOCK_TSC_STABLE_BIT in its exported
PV clock.
Note that KVM has no understanding of vCPU being currently parked.
Without PVCLOCK_TSC_STABLE_BIT the sched clock is marked unstable in
the guest's kvm_sched_clock_init().
This causes a performance regressions to show in some tests.
Fix this issue by writing the special value of "1" also to TSCs of parked
vCPUs on VM reset.
Reproducing the issue:
1) Boot a VM with "-smp 2,maxcpus=3" or similar
2) device_add host-x86_64-cpu,id=vcpu,node-id=0,socket-id=0,core-id=2,thread-id=0
3) Wait a few seconds
4) device_del vcpu
5) Inside the VM run:
# echo "t" >/proc/sysrq-trigger; dmesg | grep sched_clock_stable
Observe the sched_clock_stable() value is 1.
6) Reboot the VM
7) Once the VM boots once again run inside it:
# echo "t" >/proc/sysrq-trigger; dmesg | grep sched_clock_stable
Observe the sched_clock_stable() value is now 0.
Fixes: 5286c3662294 ("target/i386: properly reset TSC on reset")
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Link: https://lore.kernel.org/r/5a605a88e9a231386dc803c60f5fed9b48108139.1734014926.git.maciej.szmigiero@oracle.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Building without CONFIG_HYPERV is currently broken due to a missing
symbol 'hyperv_syndbg_query_options'. Add it to the stubs
that exist for that very reasons.
Reported-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When AVX10 enable bit is set, the 0x24 leaf will be present as "AVX10
Converged Vector ISA leaf" containing fields for the version number and
the supported vector bit lengths.
Introduce avx10-version property so that avx10 version can be controlled
by user and cpu model. Per spec, avx10 version can never be 0, the default
value of avx10-version is set to 0 to determine whether it is specified by
user. The default can come from the device model or, for the max model,
from KVM's reported value.
Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Link: https://lore.kernel.org/r/20241028024512.156724-3-tao1.su@linux.intel.com
Link: https://lore.kernel.org/r/20241028024512.156724-4-tao1.su@linux.intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Xuelian Guo <xuelian.guo@intel.com>
Link: https://lore.kernel.org/r/20241031085233.425388-5-tao1.su@linux.intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Right now, QEMU is using the "feature" and "bits" fields of ExtSaveArea
to query the accelerator for the support status of extended save areas.
This is a problem for AVX10, which attaches two feature bits (AVX512F
and AVX10) to the same extended save states.
To keep the AVX10 hacks to the minimum, limit usage of esa->features
and esa->bits. Instead, just query the accelerator for the 0xD leaf.
Do it in common code and clear esa->size if an extended save state is
unsupported.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20241031085233.425388-3-tao1.su@linux.intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
'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>
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>
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: d8701185f40c ("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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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 662175b91ff ("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: f5cc5a5c1686 ("i386: split cpu accelerators from cpu.c, using AccelCPUClass")
Fixes: 662175b91ff2 ("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>
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>
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>
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>
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>
