KVM: s390: Populate mask of non-hypervisor managed facility bits (60a37709) · Commits · 戴 / test

When a guest is initializing, KVM provides facility bits that can be successfully used by the guest. It's done by applying kvm_s390_fac_list_mask mask on host facility bits stored by the STFLE instruction. Facility bits can be one of two kinds: it's either a hypervisor managed bit or non-hypervisor managed. The hardware provides information which bits need special handling. Let's automatically passthrough to guests new facility bits, that don't require hypervisor support. Signed-off-by:

Alexander Yarygin <yarygin@linux.vnet.ibm.com> Reviewed-by:

David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by:

Eric Farman <farman@linux.vnet.ibm.com> Signed-off-by:

Christian Borntraeger <borntraeger@de.ibm.com>

arch/s390/kvm/kvm-s390.c

+16 −3

Original line number	Diff line number	Diff line
		@@ -118,9 +118,9 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
		};

		/* upper facilities limit for kvm */
		unsigned long kvm_s390_fac_list_mask[] = {
		0xffe6ffffffffffffUL,
		0x005effffffffffffUL,
		unsigned long kvm_s390_fac_list_mask[16] = {
		0xffe6000000000000UL,
		0x005e000000000000UL,
		};

		unsigned long kvm_s390_fac_list_mask_size(void)
		@@ -2985,13 +2985,26 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
		return;
		}

		static inline unsigned long nonhyp_mask(int i)
		{
		unsigned int nonhyp_fai = (sclp.hmfai << i * 2) >> 30;

		return 0x0000ffffffffffffUL >> (nonhyp_fai << 4);
		}

		static int __init kvm_s390_init(void)
		{
		int i;

		if (!sclp.has_sief2) {
		pr_info("SIE not available\n");
		return -ENODEV;
		}

		for (i = 0; i < 16; i++)
		kvm_s390_fac_list_mask[i] \|=
		S390_lowcore.stfle_fac_list[i] & nonhyp_mask(i);

		return kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
		}

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