From: Fangyu Yu When executing kvm_riscv_vcpu_aia_has_interrupts, the vCPU may have migrated and the IMSIC VS-file have not been updated yet, currently the HGEIP CSR should be read from the imsic->vsfile_cpu ( the pCPU before migration ) via on_each_cpu_mask, but this will trigger an IPI call and repeated IPI within a period of time is expensive in a many-core systems. Just let the vCPU execute and update the correct IMSIC VS-file via kvm_riscv_vcpu_aia_imsic_update may be a simple solution. Fixes: 4cec89db80ba ("RISC-V: KVM: Move HGEI[E|P] CSR access to IMSIC virtualization") Signed-off-by: Fangyu Yu --- arch/riscv/kvm/aia_imsic.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/riscv/kvm/aia_imsic.c b/arch/riscv/kvm/aia_imsic.c index fda0346f0ea1..168c02ad0a78 100644 --- a/arch/riscv/kvm/aia_imsic.c +++ b/arch/riscv/kvm/aia_imsic.c @@ -689,8 +689,12 @@ bool kvm_riscv_vcpu_aia_imsic_has_interrupt(struct kvm_vcpu *vcpu) */ read_lock_irqsave(&imsic->vsfile_lock, flags); - if (imsic->vsfile_cpu > -1) - ret = !!(csr_read(CSR_HGEIP) & BIT(imsic->vsfile_hgei)); + if (imsic->vsfile_cpu > -1) { + if (imsic->vsfile_cpu != smp_processor_id()) + ret = true; + else + ret = !!(csr_read(CSR_HGEIP) & BIT(imsic->vsfile_hgei)); + } read_unlock_irqrestore(&imsic->vsfile_lock, flags); return ret; -- 2.50.1