Merge tag 'kvm-s390-master-5.7-3' of... (2673cb68) · Commits · 戴 / test

Merge tag 'kvm-s390-master-5.7-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD KVM: s390: Fix for running nested uner z/VM There are circumstances when running nested under z/VM that would trigger a WARN_ON_ONCE. Remove the WARN_ON_ONCE. Long term we certainly want to make this code more robust and flexible, but just returning instead of WARNING makes guest bootable again.

arch/s390/kvm/priv.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -626,10 +626,12 @@ static int handle_pqap(struct kvm_vcpu *vcpu)
		* available for the guest are AQIC and TAPQ with the t bit set
		* since we do not set IC.3 (FIII) we currently will only intercept
		* the AQIC function code.
		* Note: running nested under z/VM can result in intercepts for other
		* function codes, e.g. PQAP(QCI). We do not support this and bail out.
		*/
		reg0 = vcpu->run->s.regs.gprs[0];
		fc = (reg0 >> 24) & 0xff;
		if (WARN_ON_ONCE(fc != 0x03))
		if (fc != 0x03)
		return -EOPNOTSUPP;

		/* PQAP instruction is allowed for guest kernel only */

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