From 9e6dabeffd1d0ec2aa19aa076c4886067238d442 Mon Sep 17 00:00:00 2001 From: Cornelia Huck Date: Thu, 17 Nov 2011 11:00:41 +0100 Subject: [PATCH] KVM: s390: Fix RUNNING flag misinterpretation CPUSTAT_RUNNING was implemented signifying that a vcpu is not stopped. This is not, however, what the architecture says: RUNNING should be set when the host is acting on the behalf of the guest operating system. CPUSTAT_RUNNING has been changed to be set in kvm_arch_vcpu_load() and to be unset in kvm_arch_vcpu_put(). For signifying stopped state of a vcpu, a host-controlled bit has been used and is set/unset basically on the reverse as the old CPUSTAT_RUNNING bit (including pushing it down into stop handling proper in handle_stop()). Cc: stable@kernel.org Signed-off-by: Cornelia Huck Signed-off-by: Carsten Otte Signed-off-by: Avi Kivity --- arch/s390/include/asm/kvm_host.h | 2 +- arch/s390/kvm/diag.c | 2 +- arch/s390/kvm/intercept.c | 3 ++- arch/s390/kvm/interrupt.c | 1 + arch/s390/kvm/kvm-s390.c | 10 +++++++--- arch/s390/kvm/sigp.c | 6 +++--- 6 files changed, 15 insertions(+), 9 deletions(-) diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index 24e18473d926..20f9068cd6b5 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -47,7 +47,7 @@ struct sca_block { #define KVM_HPAGE_MASK(x) (~(KVM_HPAGE_SIZE(x) - 1)) #define KVM_PAGES_PER_HPAGE(x) (KVM_HPAGE_SIZE(x) / PAGE_SIZE) -#define CPUSTAT_HOST 0x80000000 +#define CPUSTAT_STOPPED 0x80000000 #define CPUSTAT_WAIT 0x10000000 #define CPUSTAT_ECALL_PEND 0x08000000 #define CPUSTAT_STOP_INT 0x04000000 diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c index 87cedd61be04..8943e82cd4d9 100644 --- a/arch/s390/kvm/diag.c +++ b/arch/s390/kvm/diag.c @@ -70,7 +70,7 @@ static int __diag_ipl_functions(struct kvm_vcpu *vcpu) return -EOPNOTSUPP; } - atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags); + atomic_set_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags); vcpu->run->s390_reset_flags |= KVM_S390_RESET_SUBSYSTEM; vcpu->run->s390_reset_flags |= KVM_S390_RESET_IPL; vcpu->run->s390_reset_flags |= KVM_S390_RESET_CPU_INIT; diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c index c7c51898984e..02434543eabb 100644 --- a/arch/s390/kvm/intercept.c +++ b/arch/s390/kvm/intercept.c @@ -132,7 +132,6 @@ static int handle_stop(struct kvm_vcpu *vcpu) int rc = 0; vcpu->stat.exit_stop_request++; - atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags); spin_lock_bh(&vcpu->arch.local_int.lock); if (vcpu->arch.local_int.action_bits & ACTION_STORE_ON_STOP) { vcpu->arch.local_int.action_bits &= ~ACTION_STORE_ON_STOP; @@ -149,6 +148,8 @@ static int handle_stop(struct kvm_vcpu *vcpu) } if (vcpu->arch.local_int.action_bits & ACTION_STOP_ON_STOP) { + atomic_set_mask(CPUSTAT_STOPPED, + &vcpu->arch.sie_block->cpuflags); vcpu->arch.local_int.action_bits &= ~ACTION_STOP_ON_STOP; VCPU_EVENT(vcpu, 3, "%s", "cpu stopped"); rc = -EOPNOTSUPP; diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index 87c16705b381..278ee009ce65 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -252,6 +252,7 @@ static void __do_deliver_interrupt(struct kvm_vcpu *vcpu, offsetof(struct _lowcore, restart_psw), sizeof(psw_t)); if (rc == -EFAULT) exception = 1; + atomic_clear_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags); break; case KVM_S390_PROGRAM_INT: diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 0bd3bea1e4cd..630ab65b488b 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -270,10 +270,12 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) restore_fp_regs(&vcpu->arch.guest_fpregs); restore_access_regs(vcpu->arch.guest_acrs); gmap_enable(vcpu->arch.gmap); + atomic_set_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags); } void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) { + atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags); gmap_disable(vcpu->arch.gmap); save_fp_regs(&vcpu->arch.guest_fpregs); save_access_regs(vcpu->arch.guest_acrs); @@ -301,7 +303,9 @@ static void kvm_s390_vcpu_initial_reset(struct kvm_vcpu *vcpu) int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu) { - atomic_set(&vcpu->arch.sie_block->cpuflags, CPUSTAT_ZARCH | CPUSTAT_SM); + atomic_set(&vcpu->arch.sie_block->cpuflags, CPUSTAT_ZARCH | + CPUSTAT_SM | + CPUSTAT_STOPPED); vcpu->arch.sie_block->ecb = 6; vcpu->arch.sie_block->eca = 0xC1002001U; vcpu->arch.sie_block->fac = (int) (long) facilities; @@ -428,7 +432,7 @@ static int kvm_arch_vcpu_ioctl_set_initial_psw(struct kvm_vcpu *vcpu, psw_t psw) { int rc = 0; - if (atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_RUNNING) + if (!(atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_STOPPED)) rc = -EBUSY; else { vcpu->run->psw_mask = psw.mask; @@ -501,7 +505,7 @@ rerun_vcpu: if (vcpu->sigset_active) sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved); - atomic_set_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags); + atomic_clear_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags); BUG_ON(vcpu->kvm->arch.float_int.local_int[vcpu->vcpu_id] == NULL); diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c index f815118835f3..4a488a98d7f8 100644 --- a/arch/s390/kvm/sigp.c +++ b/arch/s390/kvm/sigp.c @@ -57,8 +57,8 @@ static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr, spin_lock(&fi->lock); if (fi->local_int[cpu_addr] == NULL) rc = 3; /* not operational */ - else if (atomic_read(fi->local_int[cpu_addr]->cpuflags) - & CPUSTAT_RUNNING) { + else if (!(atomic_read(fi->local_int[cpu_addr]->cpuflags) + & CPUSTAT_STOPPED)) { *reg &= 0xffffffff00000000UL; rc = 1; /* status stored */ } else { @@ -251,7 +251,7 @@ static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address, spin_lock_bh(&li->lock); /* cpu must be in stopped state */ - if (atomic_read(li->cpuflags) & CPUSTAT_RUNNING) { + if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) { rc = 1; /* incorrect state */ *reg &= SIGP_STAT_INCORRECT_STATE; kfree(inti);