On Wed, Apr 16, 2025 at 02:52:33PM -0700, Dongli Zhang wrote: > Date: Wed, 16 Apr 2025 14:52:33 -0700 > From: Dongli Zhang <dongli.zhang@xxxxxxxxxx> > Subject: [PATCH v4 08/11] target/i386/kvm: query kvm.enable_pmu parameter > X-Mailer: git-send-email 2.43.5 > > When PMU is enabled in QEMU, there is a chance that PMU virtualization is > completely disabled by the KVM module parameter kvm.enable_pmu=N. > > The kvm.enable_pmu parameter is introduced since Linux v5.17. > Its permission is 0444. It does not change until a reload of the KVM > module. > > Read the kvm.enable_pmu value from the module sysfs to give a chance to > provide more information about vPMU enablement. > > Signed-off-by: Dongli Zhang <dongli.zhang@xxxxxxxxxx> > --- > Changed since v2: > - Rework the code flow following Zhao's suggestion. > - Return error when: > (*kvm_enable_pmu == 'N' && X86_CPU(cpu)->enable_pmu) > Changed since v3: > - Re-split the cases into enable_pmu and !enable_pmu, following Zhao's > suggestion. > - Rework the commit messages. > - Bring back global static variable 'kvm_pmu_disabled' from v2. > > target/i386/kvm/kvm.c | 61 +++++++++++++++++++++++++++++++------------ > 1 file changed, 44 insertions(+), 17 deletions(-) Reviewed-by: Zhao Liu <zhao1.liu@xxxxxxxxx>
