diff --git a/core/init.c b/core/init.c
index a1fd5f2..005ecf3 100644
--- a/core/init.c
+++ b/core/init.c
@@ -48,6 +48,7 @@
 #include <debug_descriptor.h>
 #include <occ.h>
 #include <opal-dump.h>
+#include <xscom-p9-regs.h>
 #include <xscom-p10-regs.h>
 
 enum proc_gen proc_gen;
@@ -1026,6 +1027,40 @@
         }
 }
 
+bool lpar_per_core = false;
+
+static void probe_lpar_per_core(void)
+{
+	struct cpu_thread *cpu = this_cpu();
+	uint32_t chip_id = pir_to_chip_id(cpu->pir);
+	uint32_t core_id = pir_to_core_id(cpu->pir);
+	uint64_t addr;
+	uint64_t core_thread_state;
+	int rc;
+
+	if (chip_quirk(QUIRK_MAMBO_CALLOUTS) || chip_quirk(QUIRK_AWAN))
+		return;
+
+	if (proc_gen == proc_gen_p9)
+		addr = XSCOM_ADDR_P9_EC(core_id, P9_CORE_THREAD_STATE);
+	else if (proc_gen == proc_gen_p10)
+		addr = XSCOM_ADDR_P10_EC(core_id, P10_EC_CORE_THREAD_STATE);
+	else
+		return;
+
+	rc = xscom_read(chip_id, addr, &core_thread_state);
+	if (rc) {
+		prerror("Error reading CORE_THREAD_STATE rc:%d on PIR:%x\n",
+			rc, cpu->pir);
+		return;
+	}
+
+	if (core_thread_state & PPC_BIT(62)) {
+		lpar_per_core = true;
+		prlog(PR_WARNING, "LPAR-per-core mode detected. KVM may not be usable.");
+	}
+}
+
 
 /* Called from head.S, thus no prototype. */
 void __noreturn __nomcount  main_cpu_entry(const void *fdt);
@@ -1211,6 +1246,9 @@
         /* Once all CPU are up apply this workaround */
         mask_pc_system_xstop();
 
+	/* P9/10 may be in LPAR-per-core mode, which is incompatible with KVM */
+	probe_lpar_per_core();
+
 	/* Add the /opal node to the device-tree */
 	add_opal_node();
 
diff --git a/hdata/cpu-common.c b/hdata/cpu-common.c
index 2248f9b..4ba1430 100644
--- a/hdata/cpu-common.c
+++ b/hdata/cpu-common.c
@@ -127,6 +127,8 @@
 		dt_add_property_cells(cpu, "ibm,mmu-pid-bits", 20);
 		dt_add_property_cells(cpu, "ibm,mmu-lpid-bits", 12);
 	}
+	if (lpar_per_core)
+		dt_add_property(cpu, "ibm,mmu-lpar-per-core", NULL, 0);
 
 	/* HPT segment page size encodings, common to all supported CPUs */
 	dt_add_property_cells(cpu, "ibm,segment-page-sizes",
diff --git a/hdata/test/hdata_to_dt.c b/hdata/test/hdata_to_dt.c
index 1729f1c..ead6e3c 100644
--- a/hdata/test/hdata_to_dt.c
+++ b/hdata/test/hdata_to_dt.c
@@ -104,6 +104,8 @@
 
 unsigned int cpu_thread_count = 8;
 
+bool lpar_per_core;
+
 static inline unsigned long mfspr(unsigned int spr)
 {
 	assert(spr == SPR_PVR);
diff --git a/include/skiboot.h b/include/skiboot.h
index db08f45..b0b75a4 100644
--- a/include/skiboot.h
+++ b/include/skiboot.h
@@ -103,6 +103,8 @@
 };
 extern enum proc_gen proc_gen;
 
+extern bool lpar_per_core;
+
 extern unsigned int pcie_max_link_speed;
 
 /* Convert a 4-bit number to a hex char */