1 files changed, 415 insertions, 49 deletions

diff --git a/arch/powerpc/mm/tlb-radix.c b/arch/powerpc/mm/tlb-radix.c
index a5d7309c2d05..1135b43a597c 100644
--- a/arch/powerpc/mm/tlb-radix.c
+++ b/arch/powerpc/mm/tlb-radix.c
@@ -12,6 +12,8 @@
 #include <linux/mm.h>
 #include <linux/hugetlb.h>
 #include <linux/memblock.h>
+#include <linux/mmu_context.h>
+#include <linux/sched/mm.h>
 
 #include <asm/ppc-opcode.h>
 #include <asm/tlb.h>
@@ -118,6 +120,53 @@ static inline void __tlbie_pid(unsigned long pid, unsigned long ric)
 	trace_tlbie(0, 0, rb, rs, ric, prs, r);
 }
 
+static inline void __tlbiel_lpid(unsigned long lpid, int set,
+				unsigned long ric)
+{
+	unsigned long rb,rs,prs,r;
+
+	rb = PPC_BIT(52); /* IS = 2 */
+	rb |= set << PPC_BITLSHIFT(51);
+	rs = 0;  /* LPID comes from LPIDR */
+	prs = 0; /* partition scoped */
+	r = 1;   /* radix format */
+
+	asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
+		     : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
+	trace_tlbie(lpid, 1, rb, rs, ric, prs, r);
+}
+
+static inline void __tlbie_lpid(unsigned long lpid, unsigned long ric)
+{
+	unsigned long rb,rs,prs,r;
+
+	rb = PPC_BIT(52); /* IS = 2 */
+	rs = lpid;
+	prs = 0; /* partition scoped */
+	r = 1;   /* radix format */
+
+	asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
+		     : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
+	trace_tlbie(lpid, 0, rb, rs, ric, prs, r);
+}
+
+static inline void __tlbiel_lpid_guest(unsigned long lpid, int set,
+				unsigned long ric)
+{
+	unsigned long rb,rs,prs,r;
+
+	rb = PPC_BIT(52); /* IS = 2 */
+	rb |= set << PPC_BITLSHIFT(51);
+	rs = 0;  /* LPID comes from LPIDR */
+	prs = 1; /* process scoped */
+	r = 1;   /* radix format */
+
+	asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
+		     : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
+	trace_tlbie(lpid, 1, rb, rs, ric, prs, r);
+}
+
+
 static inline void __tlbiel_va(unsigned long va, unsigned long pid,
 			       unsigned long ap, unsigned long ric)
 {
@@ -150,6 +199,22 @@ static inline void __tlbie_va(unsigned long va, unsigned long pid,
 	trace_tlbie(0, 0, rb, rs, ric, prs, r);
 }
 
+static inline void __tlbie_lpid_va(unsigned long va, unsigned long lpid,
+			      unsigned long ap, unsigned long ric)
+{
+	unsigned long rb,rs,prs,r;
+
+	rb = va & ~(PPC_BITMASK(52, 63));
+	rb |= ap << PPC_BITLSHIFT(58);
+	rs = lpid;
+	prs = 0; /* partition scoped */
+	r = 1;   /* radix format */
+
+	asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
+		     : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
+	trace_tlbie(lpid, 0, rb, rs, ric, prs, r);
+}
+
 static inline void fixup_tlbie(void)
 {
 	unsigned long pid = 0;
@@ -161,6 +226,16 @@ static inline void fixup_tlbie(void)
 	}
 }
 
+static inline void fixup_tlbie_lpid(unsigned long lpid)
+{
+	unsigned long va = ((1UL << 52) - 1);
+
+	if (cpu_has_feature(CPU_FTR_P9_TLBIE_BUG)) {
+		asm volatile("ptesync": : :"memory");
+		__tlbie_lpid_va(va, lpid, mmu_get_ap(MMU_PAGE_64K), RIC_FLUSH_TLB);
+	}
+}
+
 /*
  * We use 128 set in radix mode and 256 set in hpt mode.
  */
@@ -214,6 +289,86 @@ static inline void _tlbie_pid(unsigned long pid, unsigned long ric)
 	asm volatile("eieio; tlbsync; ptesync": : :"memory");
 }
 
+static inline void _tlbiel_lpid(unsigned long lpid, unsigned long ric)
+{
+	int set;
+
+	VM_BUG_ON(mfspr(SPRN_LPID) != lpid);
+
+	asm volatile("ptesync": : :"memory");
+
+	/*
+	 * Flush the first set of the TLB, and if we're doing a RIC_FLUSH_ALL,
+	 * also flush the entire Page Walk Cache.
+	 */
+	__tlbiel_lpid(lpid, 0, ric);
+
+	/* For PWC, only one flush is needed */
+	if (ric == RIC_FLUSH_PWC) {
+		asm volatile("ptesync": : :"memory");
+		return;
+	}
+
+	/* For the remaining sets, just flush the TLB */
+	for (set = 1; set < POWER9_TLB_SETS_RADIX ; set++)
+		__tlbiel_lpid(lpid, set, RIC_FLUSH_TLB);
+
+	asm volatile("ptesync": : :"memory");
+	asm volatile(PPC_INVALIDATE_ERAT "; isync" : : :"memory");
+}
+
+static inline void _tlbie_lpid(unsigned long lpid, unsigned long ric)
+{
+	asm volatile("ptesync": : :"memory");
+
+	/*
+	 * Workaround the fact that the "ric" argument to __tlbie_pid
+	 * must be a compile-time contraint to match the "i" constraint
+	 * in the asm statement.
+	 */
+	switch (ric) {
+	case RIC_FLUSH_TLB:
+		__tlbie_lpid(lpid, RIC_FLUSH_TLB);
+		break;
+	case RIC_FLUSH_PWC:
+		__tlbie_lpid(lpid, RIC_FLUSH_PWC);
+		break;
+	case RIC_FLUSH_ALL:
+	default:
+		__tlbie_lpid(lpid, RIC_FLUSH_ALL);
+	}
+	fixup_tlbie_lpid(lpid);
+	asm volatile("eieio; tlbsync; ptesync": : :"memory");
+}
+
+static inline void _tlbiel_lpid_guest(unsigned long lpid, unsigned long ric)
+{
+	int set;
+
+	VM_BUG_ON(mfspr(SPRN_LPID) != lpid);
+
+	asm volatile("ptesync": : :"memory");
+
+	/*
+	 * Flush the first set of the TLB, and if we're doing a RIC_FLUSH_ALL,
+	 * also flush the entire Page Walk Cache.
+	 */
+	__tlbiel_lpid_guest(lpid, 0, ric);
+
+	/* For PWC, only one flush is needed */
+	if (ric == RIC_FLUSH_PWC) {
+		asm volatile("ptesync": : :"memory");
+		return;
+	}
+
+	/* For the remaining sets, just flush the TLB */
+	for (set = 1; set < POWER9_TLB_SETS_RADIX ; set++)
+		__tlbiel_lpid_guest(lpid, set, RIC_FLUSH_TLB);
+
+	asm volatile("ptesync": : :"memory");
+}
+
+
 static inline void __tlbiel_va_range(unsigned long start, unsigned long end,
 				    unsigned long pid, unsigned long page_size,
 				    unsigned long psize)
@@ -268,6 +423,17 @@ static inline void _tlbie_va(unsigned long va, unsigned long pid,
 	asm volatile("eieio; tlbsync; ptesync": : :"memory");
 }
 
+static inline void _tlbie_lpid_va(unsigned long va, unsigned long lpid,
+			      unsigned long psize, unsigned long ric)
+{
+	unsigned long ap = mmu_get_ap(psize);
+
+	asm volatile("ptesync": : :"memory");
+	__tlbie_lpid_va(va, lpid, ap, ric);
+	fixup_tlbie_lpid(lpid);
+	asm volatile("eieio; tlbsync; ptesync": : :"memory");
+}
+
 static inline void _tlbie_va_range(unsigned long start, unsigned long end,
 				    unsigned long pid, unsigned long page_size,
 				    unsigned long psize, bool also_pwc)
@@ -340,6 +506,15 @@ void radix__local_flush_tlb_page(struct vm_area_struct *vma, unsigned long vmadd
 }
 EXPORT_SYMBOL(radix__local_flush_tlb_page);
 
+static bool mm_is_singlethreaded(struct mm_struct *mm)
+{
+	if (atomic_read(&mm->context.copros) > 0)
+		return false;
+	if (atomic_read(&mm->mm_users) <= 1 && current->mm == mm)
+		return true;
+	return false;
+}
+
 static bool mm_needs_flush_escalation(struct mm_struct *mm)
 {
 	/*
@@ -347,10 +522,47 @@ static bool mm_needs_flush_escalation(struct mm_struct *mm)
 	 * caching PTEs and not flushing them properly when
 	 * RIC = 0 for a PID/LPID invalidate
 	 */
-	return atomic_read(&mm->context.copros) != 0;
+	if (atomic_read(&mm->context.copros) > 0)
+		return true;
+	return false;
 }
 
 #ifdef CONFIG_SMP
+static void do_exit_flush_lazy_tlb(void *arg)
+{
+	struct mm_struct *mm = arg;
+	unsigned long pid = mm->context.id;
+
+	if (current->mm == mm)
+		return; /* Local CPU */
+
+	if (current->active_mm == mm) {
+		/*
+		 * Must be a kernel thread because sender is single-threaded.
+		 */
+		BUG_ON(current->mm);
+		mmgrab(&init_mm);
+		switch_mm(mm, &init_mm, current);
+		current->active_mm = &init_mm;
+		mmdrop(mm);
+	}
+	_tlbiel_pid(pid, RIC_FLUSH_ALL);
+}
+
+static void exit_flush_lazy_tlbs(struct mm_struct *mm)
+{
+	/*
+	 * Would be nice if this was async so it could be run in
+	 * parallel with our local flush, but generic code does not
+	 * give a good API for it. Could extend the generic code or
+	 * make a special powerpc IPI for flushing TLBs.
+	 * For now it's not too performance critical.
+	 */
+	smp_call_function_many(mm_cpumask(mm), do_exit_flush_lazy_tlb,
+				(void *)mm, 1);
+	mm_reset_thread_local(mm);
+}
+
 void radix__flush_tlb_mm(struct mm_struct *mm)
 {
 	unsigned long pid;
@@ -360,18 +572,30 @@ void radix__flush_tlb_mm(struct mm_struct *mm)
 		return;
 
 	preempt_disable();
+	/*
+	 * Order loads of mm_cpumask vs previous stores to clear ptes before
+	 * the invalidate. See barrier in switch_mm_irqs_off
+	 */
+	smp_mb();
 	if (!mm_is_thread_local(mm)) {
+		if (unlikely(mm_is_singlethreaded(mm))) {
+			exit_flush_lazy_tlbs(mm);
+			goto local;
+		}
+
 		if (mm_needs_flush_escalation(mm))
 			_tlbie_pid(pid, RIC_FLUSH_ALL);
 		else
 			_tlbie_pid(pid, RIC_FLUSH_TLB);
-	} else
+	} else {
+local:
 		_tlbiel_pid(pid, RIC_FLUSH_TLB);
+	}
 	preempt_enable();
 }
 EXPORT_SYMBOL(radix__flush_tlb_mm);
 
-void radix__flush_all_mm(struct mm_struct *mm)
+static void __flush_all_mm(struct mm_struct *mm, bool fullmm)
 {
 	unsigned long pid;
 
@@ -380,12 +604,25 @@ void radix__flush_all_mm(struct mm_struct *mm)
 		return;
 
 	preempt_disable();
-	if (!mm_is_thread_local(mm))
+	smp_mb(); /* see radix__flush_tlb_mm */
+	if (!mm_is_thread_local(mm)) {
+		if (unlikely(mm_is_singlethreaded(mm))) {
+			if (!fullmm) {
+				exit_flush_lazy_tlbs(mm);
+				goto local;
+			}
+		}
 		_tlbie_pid(pid, RIC_FLUSH_ALL);
-	else
+	} else {
+local:
 		_tlbiel_pid(pid, RIC_FLUSH_ALL);
+	}
 	preempt_enable();
 }
+void radix__flush_all_mm(struct mm_struct *mm)
+{
+	__flush_all_mm(mm, false);
+}
 EXPORT_SYMBOL(radix__flush_all_mm);
 
 void radix__flush_tlb_pwc(struct mmu_gather *tlb, unsigned long addr)
@@ -404,10 +641,17 @@ void radix__flush_tlb_page_psize(struct mm_struct *mm, unsigned long vmaddr,
 		return;
 
 	preempt_disable();
-	if (!mm_is_thread_local(mm))
+	smp_mb(); /* see radix__flush_tlb_mm */
+	if (!mm_is_thread_local(mm)) {
+		if (unlikely(mm_is_singlethreaded(mm))) {
+			exit_flush_lazy_tlbs(mm);
+			goto local;
+		}
 		_tlbie_va(vmaddr, pid, psize, RIC_FLUSH_TLB);
-	else
+	} else {
+local:
 		_tlbiel_va(vmaddr, pid, psize, RIC_FLUSH_TLB);
+	}
 	preempt_enable();
 }
 
@@ -445,35 +689,38 @@ EXPORT_SYMBOL(radix__flush_tlb_kernel_range);
 static unsigned long tlb_single_page_flush_ceiling __read_mostly = 33;
 static unsigned long tlb_local_single_page_flush_ceiling __read_mostly = POWER9_TLB_SETS_RADIX * 2;
 
-void radix__flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
-		     unsigned long end)
+static inline void __radix__flush_tlb_range(struct mm_struct *mm,
+					unsigned long start, unsigned long end,
+					bool flush_all_sizes)
 
 {
-	struct mm_struct *mm = vma->vm_mm;
 	unsigned long pid;
 	unsigned int page_shift = mmu_psize_defs[mmu_virtual_psize].shift;
 	unsigned long page_size = 1UL << page_shift;
 	unsigned long nr_pages = (end - start) >> page_shift;
 	bool local, full;
 
-#ifdef CONFIG_HUGETLB_PAGE
-	if (is_vm_hugetlb_page(vma))
-		return radix__flush_hugetlb_tlb_range(vma, start, end);
-#endif
-
 	pid = mm->context.id;
 	if (unlikely(pid == MMU_NO_CONTEXT))
 		return;
 
 	preempt_disable();
-	if (mm_is_thread_local(mm)) {
-		local = true;
-		full = (end == TLB_FLUSH_ALL ||
-				nr_pages > tlb_local_single_page_flush_ceiling);
-	} else {
+	smp_mb(); /* see radix__flush_tlb_mm */
+	if (!mm_is_thread_local(mm)) {
+		if (unlikely(mm_is_singlethreaded(mm))) {
+			if (end != TLB_FLUSH_ALL) {
+				exit_flush_lazy_tlbs(mm);
+				goto is_local;
+			}
+		}
 		local = false;
 		full = (end == TLB_FLUSH_ALL ||
 				nr_pages > tlb_single_page_flush_ceiling);
+	} else {
+is_local:
+		local = true;
+		full = (end == TLB_FLUSH_ALL ||
+				nr_pages > tlb_local_single_page_flush_ceiling);
 	}
 
 	if (full) {
@@ -486,37 +733,64 @@ void radix__flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
 				_tlbie_pid(pid, RIC_FLUSH_TLB);
 		}
 	} else {
-		bool hflush = false;
+		bool hflush = flush_all_sizes;
+		bool gflush = flush_all_sizes;
 		unsigned long hstart, hend;
+		unsigned long gstart, gend;
 
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-		hstart = (start + HPAGE_PMD_SIZE - 1) >> HPAGE_PMD_SHIFT;
-		hend = end >> HPAGE_PMD_SHIFT;
-		if (hstart < hend) {
-			hstart <<= HPAGE_PMD_SHIFT;
-			hend <<= HPAGE_PMD_SHIFT;
+		if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE))
 			hflush = true;
+
+		if (hflush) {
+			hstart = (start + PMD_SIZE - 1) & PMD_MASK;
+			hend = end & PMD_MASK;
+			if (hstart == hend)
+				hflush = false;
+		}
+
+		if (gflush) {
+			gstart = (start + PUD_SIZE - 1) & PUD_MASK;
+			gend = end & PUD_MASK;
+			if (gstart == gend)
+				gflush = false;
 		}
-#endif
 
 		asm volatile("ptesync": : :"memory");
 		if (local) {
 			__tlbiel_va_range(start, end, pid, page_size, mmu_virtual_psize);
 			if (hflush)
 				__tlbiel_va_range(hstart, hend, pid,
-						HPAGE_PMD_SIZE, MMU_PAGE_2M);
+						PMD_SIZE, MMU_PAGE_2M);
+			if (gflush)
+				__tlbiel_va_range(gstart, gend, pid,
+						PUD_SIZE, MMU_PAGE_1G);
 			asm volatile("ptesync": : :"memory");
 		} else {
 			__tlbie_va_range(start, end, pid, page_size, mmu_virtual_psize);
 			if (hflush)
 				__tlbie_va_range(hstart, hend, pid,
-						HPAGE_PMD_SIZE, MMU_PAGE_2M);
+						PMD_SIZE, MMU_PAGE_2M);
+			if (gflush)
+				__tlbie_va_range(gstart, gend, pid,
+						PUD_SIZE, MMU_PAGE_1G);
 			fixup_tlbie();
 			asm volatile("eieio; tlbsync; ptesync": : :"memory");
 		}
 	}
 	preempt_enable();
 }
+
+void radix__flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+		     unsigned long end)
+
+{
+#ifdef CONFIG_HUGETLB_PAGE
+	if (is_vm_hugetlb_page(vma))
+		return radix__flush_hugetlb_tlb_range(vma, start, end);
+#endif
+
+	__radix__flush_tlb_range(vma->vm_mm, start, end, false);
+}
 EXPORT_SYMBOL(radix__flush_tlb_range);
 
 static int radix_get_mmu_psize(int page_size)
@@ -534,6 +808,49 @@ static int radix_get_mmu_psize(int page_size)
 	return psize;
 }
 
+/*
+ * Flush partition scoped LPID address translation for all CPUs.
+ */
+void radix__flush_tlb_lpid_page(unsigned int lpid,
+					unsigned long addr,
+					unsigned long page_size)
+{
+	int psize = radix_get_mmu_psize(page_size);
+
+	_tlbie_lpid_va(addr, lpid, psize, RIC_FLUSH_TLB);
+}
+EXPORT_SYMBOL_GPL(radix__flush_tlb_lpid_page);
+
+/*
+ * Flush partition scoped PWC from LPID for all CPUs.
+ */
+void radix__flush_pwc_lpid(unsigned int lpid)
+{
+	_tlbie_lpid(lpid, RIC_FLUSH_PWC);
+}
+EXPORT_SYMBOL_GPL(radix__flush_pwc_lpid);
+
+/*
+ * Flush partition scoped translations from LPID (=LPIDR)
+ */
+void radix__local_flush_tlb_lpid(unsigned int lpid)
+{
+	_tlbiel_lpid(lpid, RIC_FLUSH_ALL);
+}
+EXPORT_SYMBOL_GPL(radix__local_flush_tlb_lpid);
+
+/*
+ * Flush process scoped translations from LPID (=LPIDR).
+ * Important difference, the guest normally manages its own translations,
+ * but some cases e.g., vCPU CPU migration require KVM to flush.
+ */
+void radix__local_flush_tlb_lpid_guest(unsigned int lpid)
+{
+	_tlbiel_lpid_guest(lpid, RIC_FLUSH_ALL);
+}
+EXPORT_SYMBOL_GPL(radix__local_flush_tlb_lpid_guest);
+
+
 static void radix__flush_tlb_pwc_range_psize(struct mm_struct *mm, unsigned long start,
 				  unsigned long end, int psize);
 
@@ -542,6 +859,8 @@ void radix__tlb_flush(struct mmu_gather *tlb)
 	int psize = 0;
 	struct mm_struct *mm = tlb->mm;
 	int page_size = tlb->page_size;
+	unsigned long start = tlb->start;
+	unsigned long end = tlb->end;
 
 	/*
 	 * if page size is not something we understand, do a full mm flush
@@ -551,16 +870,46 @@ void radix__tlb_flush(struct mmu_gather *tlb)
 	 * See the comment for radix in arch_exit_mmap().
 	 */
 	if (tlb->fullmm) {
-		radix__flush_all_mm(mm);
+		__flush_all_mm(mm, true);
+#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLB_PAGE)
+	} else if (mm_tlb_flush_nested(mm)) {
+		/*
+		 * If there is a concurrent invalidation that is clearing ptes,
+		 * then it's possible this invalidation will miss one of those
+		 * cleared ptes and miss flushing the TLB. If this invalidate
+		 * returns before the other one flushes TLBs, that can result
+		 * in it returning while there are still valid TLBs inside the
+		 * range to be invalidated.
+		 *
+		 * See mm/memory.c:tlb_finish_mmu() for more details.
+		 *
+		 * The solution to this is ensure the entire range is always
+		 * flushed here. The problem for powerpc is that the flushes
+		 * are page size specific, so this "forced flush" would not
+		 * do the right thing if there are a mix of page sizes in
+		 * the range to be invalidated. So use __flush_tlb_range
+		 * which invalidates all possible page sizes in the range.
+		 *
+		 * PWC flush probably is not be required because the core code
+		 * shouldn't free page tables in this path, but accounting
+		 * for the possibility makes us a bit more robust.
+		 *
+		 * need_flush_all is an uncommon case because page table
+		 * teardown should be done with exclusive locks held (but
+		 * after locks are dropped another invalidate could come
+		 * in), it could be optimized further if necessary.
+		 */
+		if (!tlb->need_flush_all)
+			__radix__flush_tlb_range(mm, start, end, true);
+		else
+			radix__flush_all_mm(mm);
+#endif
 	} else if ( (psize = radix_get_mmu_psize(page_size)) == -1) {
 		if (!tlb->need_flush_all)
 			radix__flush_tlb_mm(mm);
 		else
 			radix__flush_all_mm(mm);
 	} else {
-		unsigned long start = tlb->start;
-		unsigned long end = tlb->end;
-
 		if (!tlb->need_flush_all)
 			radix__flush_tlb_range_psize(mm, start, end, psize);
 		else
@@ -584,24 +933,33 @@ static inline void __radix__flush_tlb_range_psize(struct mm_struct *mm,
 		return;
 
 	preempt_disable();
-	if (mm_is_thread_local(mm)) {
-		local = true;
-		full = (end == TLB_FLUSH_ALL ||
-				nr_pages > tlb_local_single_page_flush_ceiling);
-	} else {
+	smp_mb(); /* see radix__flush_tlb_mm */
+	if (!mm_is_thread_local(mm)) {
+		if (unlikely(mm_is_singlethreaded(mm))) {
+			if (end != TLB_FLUSH_ALL) {
+				exit_flush_lazy_tlbs(mm);
+				goto is_local;
+			}
+		}
 		local = false;
 		full = (end == TLB_FLUSH_ALL ||
 				nr_pages > tlb_single_page_flush_ceiling);
+	} else {
+is_local:
+		local = true;
+		full = (end == TLB_FLUSH_ALL ||
+				nr_pages > tlb_local_single_page_flush_ceiling);
 	}
 
 	if (full) {
-		if (!local && mm_needs_flush_escalation(mm))
-			also_pwc = true;
-
-		if (local)
+		if (local) {
 			_tlbiel_pid(pid, also_pwc ? RIC_FLUSH_ALL : RIC_FLUSH_TLB);
-		else
-			_tlbie_pid(pid, also_pwc ? RIC_FLUSH_ALL: RIC_FLUSH_TLB);
+		} else {
+			if (mm_needs_flush_escalation(mm))
+				also_pwc = true;
+
+			_tlbie_pid(pid, also_pwc ? RIC_FLUSH_ALL : RIC_FLUSH_TLB);
+		}
 	} else {
 		if (local)
 			_tlbiel_va_range(start, end, pid, page_size, psize, also_pwc);
@@ -642,11 +1000,17 @@ void radix__flush_tlb_collapsed_pmd(struct mm_struct *mm, unsigned long addr)
 
 	/* Otherwise first do the PWC, then iterate the pages. */
 	preempt_disable();
-
-	if (mm_is_thread_local(mm)) {
-		_tlbiel_va_range(addr, end, pid, PAGE_SIZE, mmu_virtual_psize, true);
-	} else {
+	smp_mb(); /* see radix__flush_tlb_mm */
+	if (!mm_is_thread_local(mm)) {
+		if (unlikely(mm_is_singlethreaded(mm))) {
+			exit_flush_lazy_tlbs(mm);
+			goto local;
+		}
 		_tlbie_va_range(addr, end, pid, PAGE_SIZE, mmu_virtual_psize, true);
+		goto local;
+	} else {
+local:
+		_tlbiel_va_range(addr, end, pid, PAGE_SIZE, mmu_virtual_psize, true);
 	}
 
 	preempt_enable();
@@ -733,6 +1097,8 @@ extern void radix_kvm_prefetch_workaround(struct mm_struct *mm)
 		for (; sib <= cpu_last_thread_sibling(cpu) && !flush; sib++) {
 			if (sib == cpu)
 				continue;
+			if (!cpu_possible(sib))
+				continue;
 			if (paca_ptrs[sib]->kvm_hstate.kvm_vcpu)
 				flush = true;
 		}