Merge tag 'kvmarm-fixes-5.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master

bonzini · bonzini · commit e2e1a1c86bf3 · 2020-10-03T05:07:59.000-04:00
KVM/arm64 fixes for 5.9, take #3 - Fix synchronization of VTTBR update on TLB invalidation for nVHE systems
diff --git a/arch/arm64/kvm/hyp/nvhe/tlb.c b/arch/arm64/kvm/hyp/nvhe/tlb.c
@@ -31,7 +31,14 @@ static void __tlb_switch_to_guest(struct kvm_s2_mmu *mmu,
 		isb();
 	}
 
+	/*
+	 * __load_guest_stage2() includes an ISB only when the AT
+	 * workaround is applied. Take care of the opposite condition,
+	 * ensuring that we always have an ISB, but not two ISBs back
+	 * to back.
+	 */
 	__load_guest_stage2(mmu);
+	asm(ALTERNATIVE("isb", "nop", ARM64_WORKAROUND_SPECULATIVE_AT));
 }
 
 static void __tlb_switch_to_host(struct tlb_inv_context *cxt)

Original file line number	Diff line number	Diff line change
`@@ -31,7 +31,14 @@ static void __tlb_switch_to_guest(struct kvm_s2_mmu *mmu,`
`31`	`31`	`isb();`
`32`	`32`	`}`
`33`	`33`
	`34`	`+ /*`
	`35`	`+ * __load_guest_stage2() includes an ISB only when the AT`
	`36`	`+ * workaround is applied. Take care of the opposite condition,`
	`37`	`+ * ensuring that we always have an ISB, but not two ISBs back`
	`38`	`+ * to back.`
	`39`	`+ */`
`34`	`40`	`__load_guest_stage2(mmu);`
	`41`	`+ asm(ALTERNATIVE("isb", "nop", ARM64_WORKAROUND_SPECULATIVE_AT));`
`35`	`42`	`}`
`36`	`43`
`37`	`44`	`static void __tlb_switch_to_host(struct tlb_inv_context *cxt)`