From 2e5c06197012cd8491d3bb09eb8be325706b4efa Mon Sep 17 00:00:00 2001 From: David Gibson Date: Fri, 24 Jul 2015 05:26:14 +0200 Subject: [PATCH 52/58] xics_kvm: Don't enable KVM_CAP_IRQ_XICS if already enabled Message-id: <1437715580-14817-23-git-send-email-dgibson@redhat.com> Patchwork-id: 67139 O-Subject: [RHEL7.2 qemu-kvm-rhev PATCHv3 22/28] xics_kvm: Don't enable KVM_CAP_IRQ_XICS if already enabled Bugzilla: 1211117 RH-Acked-by: Laurent Vivier RH-Acked-by: Igor Mammedov RH-Acked-by: Laszlo Ersek When supporting CPU hot removal by parking the vCPU fd and reusing it during hotplug again, there can be cases where we try to reenable KVM_CAP_IRQ_XICS CAP for the vCPU for which it was already enabled. Introduce a boolean member in ICPState to track this and don't reenable the CAP if it was already enabled earlier. Re-enabling this CAP should ideally work, but currently it results in kernel trying to create and associate ICP with this vCPU and that fails since there is already an ICP associated with it. Hence this patch is needed to work around this problem in the kernel. This change allows CPU hot removal to work for sPAPR. Signed-off-by: Bharata B Rao Reviewed-by: David Gibson Signed-off-by: David Gibson Signed-off-by: Alexander Graf (cherry picked from commit a45863bda90daa8ec39e5a312b9734fd4665b016) Signed-off-by: David Gibson Signed-off-by: Miroslav Rezanina --- hw/intc/xics_kvm.c | 10 ++++++++++ include/hw/ppc/xics.h | 1 + 2 files changed, 11 insertions(+) diff --git a/hw/intc/xics_kvm.c b/hw/intc/xics_kvm.c index ea886da..d58729c 100644 --- a/hw/intc/xics_kvm.c +++ b/hw/intc/xics_kvm.c @@ -331,6 +331,15 @@ static void xics_kvm_cpu_setup(XICSState *icp, PowerPCCPU *cpu) abort(); } + /* + * If we are reusing a parked vCPU fd corresponding to the CPU + * which was hot-removed earlier we don't have to renable + * KVM_CAP_IRQ_XICS capability again. + */ + if (ss->cap_irq_xics_enabled) { + return; + } + if (icpkvm->kernel_xics_fd != -1) { int ret; @@ -343,6 +352,7 @@ static void xics_kvm_cpu_setup(XICSState *icp, PowerPCCPU *cpu) kvm_arch_vcpu_id(cs), strerror(errno)); exit(1); } + ss->cap_irq_xics_enabled = true; } } diff --git a/include/hw/ppc/xics.h b/include/hw/ppc/xics.h index a214dd7..355a966 100644 --- a/include/hw/ppc/xics.h +++ b/include/hw/ppc/xics.h @@ -109,6 +109,7 @@ struct ICPState { uint8_t pending_priority; uint8_t mfrr; qemu_irq output; + bool cap_irq_xics_enabled; }; #define TYPE_ICS "ics" -- 1.8.3.1