Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "First batch of KVM changes for 4.1

  The most interesting bit here is irqfd/ioeventfd support for ARM and
  ARM64.

  Summary:

  ARM/ARM64:
     fixes for live migration, irqfd and ioeventfd support (enabling
     vhost, too), page aging

  s390:
     interrupt handling rework, allowing to inject all local interrupts
     via new ioctl and to get/set the full local irq state for migration
     and introspection.  New ioctls to access memory by virtual address,
     and to get/set the guest storage keys.  SIMD support.

  MIPS:
     FPU and MIPS SIMD Architecture (MSA) support.  Includes some
     patches from Ralf Baechle's MIPS tree.

  x86:
     bugfixes (notably for pvclock, the others are small) and cleanups.
     Another small latency improvement for the TSC deadline timer"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (146 commits)
  KVM: use slowpath for cross page cached accesses
  kvm: mmu: lazy collapse small sptes into large sptes
  KVM: x86: Clear CR2 on VCPU reset
  KVM: x86: DR0-DR3 are not clear on reset
  KVM: x86: BSP in MSR_IA32_APICBASE is writable
  KVM: x86: simplify kvm_apic_map
  KVM: x86: avoid logical_map when it is invalid
  KVM: x86: fix mixed APIC mode broadcast
  KVM: x86: use MDA for interrupt matching
  kvm/ppc/mpic: drop unused IRQ_testbit
  KVM: nVMX: remove unnecessary double caching of MAXPHYADDR
  KVM: nVMX: checks for address bits beyond MAXPHYADDR on VM-entry
  KVM: x86: cache maxphyaddr CPUID leaf in struct kvm_vcpu
  KVM: vmx: pass error code with internal error #2
  x86: vdso: fix pvclock races with task migration
  KVM: remove kvm_read_hva and kvm_read_hva_atomic
  KVM: x86: optimize delivery of TSC deadline timer interrupt
  KVM: x86: extract blocking logic from __vcpu_run
  kvm: x86: fix x86 eflags fixed bit
  KVM: s390: migrate vcpu interrupt state
  ...

1 files changed, 24 insertions, 9 deletions

diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 33984c0..5b4d711 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -701,6 +701,13 @@ asmlinkage void do_ov(struct pt_regs *regs)
 
 int process_fpemu_return(int sig, void __user *fault_addr)
 {
+	/*
+	 * We can't allow the emulated instruction to leave any of the cause
+	 * bits set in FCSR. If they were then the kernel would take an FP
+	 * exception when restoring FP context.
+	 */
+	current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X;
+
 	if (sig == SIGSEGV || sig == SIGBUS) {
 		struct siginfo si = {0};
 		si.si_addr = fault_addr;
@@ -781,6 +788,11 @@ asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31)
 	if (notify_die(DIE_FP, "FP exception", regs, 0, regs_to_trapnr(regs),
 		       SIGFPE) == NOTIFY_STOP)
 		goto out;
+
+	/* Clear FCSR.Cause before enabling interrupts */
+	write_32bit_cp1_register(CP1_STATUS, fcr31 & ~FPU_CSR_ALL_X);
+	local_irq_enable();
+
 	die_if_kernel("FP exception in kernel code", regs);
 
 	if (fcr31 & FPU_CSR_UNI_X) {
@@ -804,18 +816,12 @@ asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31)
 		sig = fpu_emulator_cop1Handler(regs, &current->thread.fpu, 1,
 					       &fault_addr);
 
-		/*
-		 * We can't allow the emulated instruction to leave any of
-		 * the cause bit set in $fcr31.
-		 */
-		current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X;
+		/* If something went wrong, signal */
+		process_fpemu_return(sig, fault_addr);
 
 		/* Restore the hardware register state */
 		own_fpu(1);	/* Using the FPU again.	 */
 
-		/* If something went wrong, signal */
-		process_fpemu_return(sig, fault_addr);
-
 		goto out;
 	} else if (fcr31 & FPU_CSR_INV_X)
 		info.si_code = FPE_FLTINV;
@@ -1392,13 +1398,22 @@ out:
 	exception_exit(prev_state);
 }
 
-asmlinkage void do_msa_fpe(struct pt_regs *regs)
+asmlinkage void do_msa_fpe(struct pt_regs *regs, unsigned int msacsr)
 {
 	enum ctx_state prev_state;
 
 	prev_state = exception_enter();
+	if (notify_die(DIE_MSAFP, "MSA FP exception", regs, 0,
+		       regs_to_trapnr(regs), SIGFPE) == NOTIFY_STOP)
+		goto out;
+
+	/* Clear MSACSR.Cause before enabling interrupts */
+	write_msa_csr(msacsr & ~MSA_CSR_CAUSEF);
+	local_irq_enable();
+
 	die_if_kernel("do_msa_fpe invoked from kernel context!", regs);
 	force_sig(SIGFPE, current);
+out:
 	exception_exit(prev_state);
 }