In preparation to enabling Hyper-V + APICv/AVIC move
HV_APIC_ACCESS_RECOMMENDED setting out of kvm_hyperv_properties[]: the
'real' feature bit for the vAPIC features is HV_APIC_ACCESS_AVAILABLE,
HV_APIC_ACCESS_RECOMMENDED is a recommendation to use the feature which
we may not always want to give.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210902093530.345756-6-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Clean up the heading levels to use === --- ~~~, and move the command line
building near to the other execution steps.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
By default, KVM allows the guest to use all currently supported Hyper-V
enlightenments when Hyper-V CPUID interface was exposed, regardless of if
some features were not announced in guest visible CPUIDs. hv-enforce-cpuid
feature alters this behavior and only allows the guest to use exposed
Hyper-V enlightenments. The feature is supported by Linux >= 5.14 and is
not enabled by default in QEMU.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210902093530.345756-5-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
By default, KVM allows the guest to use all currently supported PV features
even when they were not announced in guest visible CPUIDs. Introduce a new
"kvm-pv-enforce-cpuid" flag to limit the supported feature set to the
exposed features. The feature is supported by Linux >= 5.10 and is not
enabled by default in QEMU.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210902093530.345756-4-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently the only difference between smp_parse and pc_smp_parse
is the support of dies parameter and the related error reporting.
With some arch compat variables like "bool dies_supported", we can
make smp_parse generic enough for all arches and the PC specific
one can be removed.
Making smp_parse() generic enough can reduce code duplication and
ease the code maintenance, and also allows extending the topology
with more arch specific members (e.g., clusters) in the future.
Suggested-by: Andrew Jones <drjones@redhat.com>
Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210929025816.21076-13-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In the real SMP hardware topology world, it's much more likely that
we have high cores-per-socket counts and few sockets totally. While
the current preference of sockets over cores in smp parsing results
in a virtual cpu topology with low cores-per-sockets counts and a
large number of sockets, which is just contrary to the real world.
Given that it is better to make the virtual cpu topology be more
reflective of the real world and also for the sake of compatibility,
we start to prefer cores over sockets over threads in smp parsing
since machine type 6.2 for different arches.
In this patch, a boolean "smp_prefer_sockets" is added, and we only
enable the old preference on older machines and enable the new one
since type 6.2 for all arches by using the machine compat mechanism.
Suggested-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@ionos.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210929025816.21076-10-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Since commit 80d7835749 (qemu-options: rewrite help for -smp options),
the preference of sockets/cores in -smp parsing is considered liable
to change, and actually we are going to change it in a coming commit.
So it'll be more stable to use detailed -smp CLIs in the testcases
that have strong dependency on the parsing results.
Currently, test_def_cpu_split use "-smp 8" and will get 8 CPU sockets
based on current parsing rule. But if we change to prefer cores over
sockets we will get one CPU socket with 8 cores, and this testcase
will not get expected numa set by default on x86_64 (Ok on aarch64).
So now explicitly use "-smp 8,sockets=8" to avoid affect from parsing
logic change.
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210929025816.21076-9-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Since commit 80d7835749 (qemu-options: rewrite help for -smp options),
the preference of sockets/cores in -smp parsing is considered liable
to change, and actually we are going to change it in a coming commit.
So it'll be more stable to use detailed -smp CLIs in testing if we
have strong dependency on the parsing results.
pc_dynamic_cpu_cfg currently assumes/needs that there will be 2 CPU
sockets with "-smp 2". To avoid breaking the test because of parsing
logic change, now explicitly use "-smp 2,sockets=2".
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210929025816.21076-8-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We have two requirements for a valid SMP configuration:
the product of "sockets * cores * threads" must represent all the
possible cpus, i.e., max_cpus, and then must include the initially
present cpus, i.e., smp_cpus.
So we only need to ensure 1) "sockets * cores * threads == maxcpus"
at first and then ensure 2) "maxcpus >= cpus". With a reasonable
order of the sanity check, we can simplify the error reporting code.
When reporting an error message we also report the exact value of
each topology member to make users easily see what's going on.
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@ionos.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210929025816.21076-7-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently we directly calculate the omitted cpus based on the given
incomplete collection of parameters. This makes some cmdlines like:
-smp maxcpus=16
-smp sockets=2,maxcpus=16
-smp sockets=2,dies=2,maxcpus=16
-smp sockets=2,cores=4,maxcpus=16
not work. We should probably set the value of cpus to match maxcpus
if it's omitted, which will make above configs start to work.
So the calculation logic of cpus/maxcpus after this patch will be:
When both maxcpus and cpus are omitted, maxcpus will be calculated
from the given parameters and cpus will be set equal to maxcpus.
When only one of maxcpus and cpus is given then the omitted one
will be set to its counterpart's value. Both maxcpus and cpus may
be specified, but maxcpus must be equal to or greater than cpus.
Note: change in this patch won't affect any existing working cmdlines
but allows more incomplete configs to be valid.
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210929025816.21076-6-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We are currently using maxcpus to calculate the omitted sockets
but using cpus to calculate the omitted cores/threads. This makes
cmdlines like:
-smp cpus=8,maxcpus=16
-smp cpus=8,cores=4,maxcpus=16
-smp cpus=8,threads=2,maxcpus=16
work fine but the ones like:
-smp cpus=8,sockets=2,maxcpus=16
-smp cpus=8,sockets=2,cores=4,maxcpus=16
-smp cpus=8,sockets=2,threads=2,maxcpus=16
break the sanity check.
Since we require for a valid config that the product of "sockets * cores
* threads" should equal to the maxcpus, we should uniformly use maxcpus
to calculate their omitted values.
Also the if-branch of "cpus == 0 || sockets == 0" was split into two
branches of "cpus == 0" and "sockets == 0" so that we can clearly read
that we are parsing the configuration with a preference on cpus over
sockets over cores over threads.
Note: change in this patch won't affect any existing working cmdlines
but improves consistency and allows more incomplete configs to be valid.
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@ionos.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210929025816.21076-5-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
To pave the way for the functional improvement in later patches,
make some refactor/cleanup for the smp parsers, including using
local maxcpus instead of ms->smp.max_cpus in the calculation,
defaulting dies to 0 initially like other members, cleanup the
sanity check for dies.
We actually also fix a hidden defect by avoiding directly using
the provided *zero value* in the calculation, which could cause
a segment fault (e.g. using dies=0 in the calculation).
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210929025816.21076-4-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In the SMP configuration, we should either provide a topology
parameter with a reasonable value (greater than zero) or just
omit it and QEMU will compute the missing value.
The users shouldn't provide a configuration with any parameter
of it specified as zero (e.g. -smp 8,sockets=0) which could
possibly cause unexpected results in the -smp parsing. So we
deprecate this kind of configurations since 6.2 by adding the
explicit sanity check.
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210929025816.21076-3-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Create and record the rt signal trampoline.
This fixes a bug wrt libgcc fallback unwinding. It expects
the stack pointer to point to the siginfo_t, whereas we had
inexplicably placed our private signal trampoline at the start
of the signal frame instead of the end. Now moot because we
have removed it from the stack frame entirely.
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210929130553.121567-21-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Mirror what the kernel does in arch/arm/kernel/signal.h,
using the old sigframe struct in the rt sigframe struct.
Update the trampoline code to match the kernel: this uses
sp-relative accesses rather than pc-relative.
Copy the code into frame->retcode from the trampoline page.
This minimises the different cases wrt arm vs thumb vs fdpic.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20210929130553.121567-6-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Paolo Bonzini