From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47753) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a9QKw-0005gZ-Cf for qemu-devel@nongnu.org; Wed, 16 Dec 2015 23:38:43 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1a9QKr-000157-BQ for qemu-devel@nongnu.org; Wed, 16 Dec 2015 23:38:42 -0500 Received: from e19.ny.us.ibm.com ([129.33.205.209]:57531) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a9QKr-00014x-7d for qemu-devel@nongnu.org; Wed, 16 Dec 2015 23:38:37 -0500 Received: from localhost by e19.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 16 Dec 2015 23:38:34 -0500 Message-ID: <56723C42.8000005@linux.vnet.ibm.com> Date: Thu, 17 Dec 2015 10:08:26 +0530 From: Aravinda Prasad MIME-Version: 1.0 References: <20151216060551.10636.77403.stgit@aravindap> <20151216060847.10636.76722.stgit@aravindap> <20151217040229.GJ3011@voom.redhat.com> In-Reply-To: <20151217040229.GJ3011@voom.redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2 4/4] spapr: Introduce FWNMI KVM capability List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: David Gibson Cc: benh@au1.ibm.com, aik@ozlabs.ru, agraf@suse.de, qemu-devel@nongnu.org, paulus@samba.org, qemu-ppc@nongnu.org, sam.bobroff@au1.ibm.com On Thursday 17 December 2015 09:32 AM, David Gibson wrote: > On Wed, Dec 16, 2015 at 11:38:47AM +0530, Aravinda Prasad wrote: >> Introduce a new KVM capability to control how KVM >> behaves on machine check exception. >> >> Without this capability, KVM redirects machine check >> exceptions to guest's 0x200 vector if the address in >> error belongs to guest. With this capability KVM >> causes a guest exit with NMI exit reason. >> >> This is required to avoid problem if a new kernel/KVM >> is used with an old QEMU. As old QEMU might not >> understand the new NMI exit type and treat it as a >> fatal error, even though the guest could have actually >> handled the error if the exception was delivered to >> guest's 0x200 interrupt vector. >> >> PS: KVM_CAP_PPC_FWNMI is set to 121 as 119 and 120 are >> used by KVM_CAP_GUEST_DEBUG_HW_BPS and KVM_CAP_GUEST_DEBUG_HW_WPS >> in KVM code, but still not reflected in QEMU code. > > The commit message seems to be written as if this were the kernel > patch adding the capability there, rather than the qemu patch using > it. > I will reword it. Regards, Aravinda >> Signed-off-by: Aravinda Prasad >> --- >> hw/ppc/spapr_rtas.c | 17 +++++++++++++++++ >> linux-headers/linux/kvm.h | 1 + >> target-ppc/kvm.c | 2 ++ >> 3 files changed, 20 insertions(+) >> >> diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c >> index 17c4672..53319da 100644 >> --- a/hw/ppc/spapr_rtas.c >> +++ b/hw/ppc/spapr_rtas.c >> @@ -38,6 +38,8 @@ >> #include >> #include "hw/ppc/spapr_drc.h" >> >> +extern int cap_fwnmi; >> + >> /* #define DEBUG_SPAPR */ >> >> #ifdef DEBUG_SPAPR >> @@ -603,9 +605,24 @@ static void rtas_ibm_nmi_register(PowerPCCPU *cpu, >> target_ulong args, >> uint32_t nret, target_ulong rets) >> { >> + int ret; >> + CPUState *cs = CPU(cpu); >> + >> + if (!cap_fwnmi) { >> + rtas_st(rets, 0, RTAS_OUT_NOT_SUPPORTED); >> + return; >> + } >> + >> spapr->mc_in_progress = false; >> qemu_cond_init(&spapr->mc_delivery_cond); >> spapr->guest_machine_check_addr = rtas_ld(args, 1); >> + >> + ret = kvm_vcpu_enable_cap(cs, KVM_CAP_PPC_FWNMI, 0); >> + if (ret < 0) { >> + rtas_st(rets, 0, RTAS_OUT_HW_ERROR); >> + return; >> + } >> + >> rtas_st(rets, 0, RTAS_OUT_SUCCESS); >> } >> >> diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h >> index 683f713..2db1fba 100644 >> --- a/linux-headers/linux/kvm.h >> +++ b/linux-headers/linux/kvm.h >> @@ -819,6 +819,7 @@ struct kvm_ppc_smmu_info { >> #define KVM_CAP_DISABLE_QUIRKS 116 >> #define KVM_CAP_X86_SMM 117 >> #define KVM_CAP_MULTI_ADDRESS_SPACE 118 >> +#define KVM_CAP_PPC_FWNMI 121 >> >> #ifdef KVM_CAP_IRQ_ROUTING >> >> diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c >> index 2bbb46d..5339c04 100644 >> --- a/target-ppc/kvm.c >> +++ b/target-ppc/kvm.c >> @@ -74,6 +74,7 @@ static int cap_ppc_watchdog; >> static int cap_papr; >> static int cap_htab_fd; >> static int cap_fixup_hcalls; >> +int cap_fwnmi; >> >> static uint32_t debug_inst_opcode; >> >> @@ -116,6 +117,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s) >> * only activated after this by kvmppc_set_papr() */ >> cap_htab_fd = kvm_check_extension(s, KVM_CAP_PPC_HTAB_FD); >> cap_fixup_hcalls = kvm_check_extension(s, KVM_CAP_PPC_FIXUP_HCALL); >> + cap_fwnmi = kvm_check_extension(s, KVM_CAP_PPC_FWNMI); >> >> if (!cap_interrupt_level) { >> fprintf(stderr, "KVM: Couldn't find level irq capability. Expect the " >> > -- Regards, Aravinda