Merge tag 'powerpc-5.10-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "Some more powerpc fixes for 5.10:

   - Three commits fixing possible missed TLB invalidations for
     multi-threaded processes when CPUs are hotplugged in and out.

   - A fix for a host crash triggerable by host userspace (qemu) in KVM
     on Power9.

   - A fix for a host crash in machine check handling when running HPT
     guests on a HPT host.

   - One commit fixing potential missed TLB invalidations when using the
     hash MMU on Power9 or later.

   - A regression fix for machines with CPUs on node 0 but no memory.

  Thanks to Aneesh Kumar K.V, Cédric Le Goater, Greg Kurz, Milan
  Mohanty, Milton Miller, Nicholas Piggin, Paul Mackerras, and Srikar
  Dronamraju"

* tag 'powerpc-5.10-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s/powernv: Fix memory corruption when saving SLB entries on MCE
  KVM: PPC: Book3S HV: XIVE: Fix vCPU id sanity check
  powerpc/numa: Fix a regression on memoryless node 0
  powerpc/64s: Trim offlined CPUs from mm_cpumasks
  kernel/cpu: add arch override for clear_tasks_mm_cpumask() mm handling
  powerpc/64s/pseries: Fix hash tlbiel_all_isa300 for guest kernels
  powerpc/64s: Fix hash ISA v3.0 TLBIEL instruction generation

3 files changed, 36 insertions, 10 deletions

diff --git a/arch/powerpc/mm/book3s64/hash_native.c b/arch/powerpc/mm/book3s64/hash_native.c
index 0203cdf48c54..52e170bd95ae 100644
--- a/arch/powerpc/mm/book3s64/hash_native.c
+++ b/arch/powerpc/mm/book3s64/hash_native.c
@@ -68,7 +68,7 @@ static __always_inline void tlbiel_hash_set_isa300(unsigned int set, unsigned in
 	rs = ((unsigned long)pid << PPC_BITLSHIFT(31));
 
 	asm volatile(PPC_TLBIEL(%0, %1, %2, %3, %4)
-		     : : "r"(rb), "r"(rs), "i"(ric), "i"(prs), "r"(r)
+		     : : "r"(rb), "r"(rs), "i"(ric), "i"(prs), "i"(r)
 		     : "memory");
 }
 
@@ -92,16 +92,15 @@ static void tlbiel_all_isa300(unsigned int num_sets, unsigned int is)
 	asm volatile("ptesync": : :"memory");
 
 	/*
-	 * Flush the first set of the TLB, and any caching of partition table
-	 * entries. Then flush the remaining sets of the TLB. Hash mode uses
-	 * partition scoped TLB translations.
+	 * Flush the partition table cache if this is HV mode.
 	 */
-	tlbiel_hash_set_isa300(0, is, 0, 2, 0);
-	for (set = 1; set < num_sets; set++)
-		tlbiel_hash_set_isa300(set, is, 0, 0, 0);
+	if (early_cpu_has_feature(CPU_FTR_HVMODE))
+		tlbiel_hash_set_isa300(0, is, 0, 2, 0);
 
 	/*
-	 * Now invalidate the process table cache.
+	 * Now invalidate the process table cache. UPRT=0 HPT modes (what
+	 * current hardware implements) do not use the process table, but
+	 * add the flushes anyway.
 	 *
 	 * From ISA v3.0B p. 1078:
 	 *     The following forms are invalid.
@@ -110,6 +109,14 @@ static void tlbiel_all_isa300(unsigned int num_sets, unsigned int is)
 	 */
 	tlbiel_hash_set_isa300(0, is, 0, 2, 1);
 
+	/*
+	 * Then flush the sets of the TLB proper. Hash mode uses
+	 * partition scoped TLB translations, which may be flushed
+	 * in !HV mode.
+	 */
+	for (set = 0; set < num_sets; set++)
+		tlbiel_hash_set_isa300(set, is, 0, 0, 0);
+
 	ppc_after_tlbiel_barrier();
 
 	asm volatile(PPC_ISA_3_0_INVALIDATE_ERAT "; isync" : : :"memory");
diff --git a/arch/powerpc/mm/book3s64/mmu_context.c b/arch/powerpc/mm/book3s64/mmu_context.c
index 1c54821de7bf..0c8557220ae2 100644
--- a/arch/powerpc/mm/book3s64/mmu_context.c
+++ b/arch/powerpc/mm/book3s64/mmu_context.c
@@ -17,6 +17,7 @@
 #include <linux/export.h>
 #include <linux/gfp.h>
 #include <linux/slab.h>
+#include <linux/cpu.h>
 
 #include <asm/mmu_context.h>
 #include <asm/pgalloc.h>
@@ -307,3 +308,22 @@ void radix__switch_mmu_context(struct mm_struct *prev, struct mm_struct *next)
 	isync();
 }
 #endif
+
+/**
+ * cleanup_cpu_mmu_context - Clean up MMU details for this CPU (newly offlined)
+ *
+ * This clears the CPU from mm_cpumask for all processes, and then flushes the
+ * local TLB to ensure TLB coherency in case the CPU is onlined again.
+ *
+ * KVM guest translations are not necessarily flushed here. If KVM started
+ * using mm_cpumask or the Linux APIs which do, this would have to be resolved.
+ */
+#ifdef CONFIG_HOTPLUG_CPU
+void cleanup_cpu_mmu_context(void)
+{
+	int cpu = smp_processor_id();
+
+	clear_tasks_mm_cpumask(cpu);
+	tlbiel_all();
+}
+#endif
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 63f61d8b55e5..f2bf98bdcea2 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -742,8 +742,7 @@ static int __init parse_numa_properties(void)
 			of_node_put(cpu);
 		}
 
-		if (likely(nid > 0))
-			node_set_online(nid);
+		node_set_online(nid);
 	}
 
 	get_n_mem_cells(&n_mem_addr_cells, &n_mem_size_cells);