Merge tag 'powerpc-4.13-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "Fixes for recently merged code:
   - a fix for the _PAGE_DEVMAP support, which was breaking KVM on
     Power9 radix
   - avoid a (harmless) lockdep warning in the early SMP code
   - return failure for some uses of dma_set_mask() rather than falling
     back to 32-bits
   - fix stack setup in watchdog soft_nmi_common() to use emergency
     stack
   - fix of_irq_to_resource() error check in of_fsl_spi_probe()

  Two fixes going to stable:
   - fix saving of Transactional Memory SPRs in core dump
   - fix __check_irq_replay missing decrementer interrupt

  And two misc:
   - fix 64-bit boot wrapper build with non-biarch compiler
   - work around a POWER9 PMU hang after state-loss idle

  Thanks to: Alistair Popple, Aneesh Kumar K.V, Cyril Bur, Gustavo
  Romero, Jose Ricardo Ziviani, Laurent Vivier, Nicholas Piggin, Oliver
  O'Halloran, Sergei Shtylyov, Suraj Jitindar Singh, Thomas Gleixner"

* tag 'powerpc-4.13-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64: Fix __check_irq_replay missing decrementer interrupt
  powerpc/perf: POWER9 PMU stops after idle workaround
  powerpc/83xx/mpc832x_rdb: fix of_irq_to_resource() error check
  powerpc/64s: Fix stack setup in watchdog soft_nmi_common()
  powerpc/powernv/pci: Return failure for some uses of dma_set_mask()
  powerpc/boot: Fix 64-bit boot wrapper build with non-biarch compiler
  powerpc/smp: Call smp_ops->setup_cpu() directly on the boot CPU
  powerpc/tm: Fix saving of TM SPRs in core dump
  powerpc/mm: Fix pmd/pte_devmap() on non-leaf entries

1 files changed, 9 insertions, 1 deletions

diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index d1da415e283c..818a58fc3f4f 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -608,9 +608,17 @@ static inline pte_t pte_mkdevmap(pte_t pte)
 	return __pte(pte_val(pte) | _PAGE_SPECIAL|_PAGE_DEVMAP);
 }
 
+/*
+ * This is potentially called with a pmd as the argument, in which case it's not
+ * safe to check _PAGE_DEVMAP unless we also confirm that _PAGE_PTE is set.
+ * That's because the bit we use for _PAGE_DEVMAP is not reserved for software
+ * use in page directory entries (ie. non-ptes).
+ */
 static inline int pte_devmap(pte_t pte)
 {
-	return !!(pte_raw(pte) & cpu_to_be64(_PAGE_DEVMAP));
+	u64 mask = cpu_to_be64(_PAGE_DEVMAP | _PAGE_PTE);
+
+	return (pte_raw(pte) & mask) == mask;
 }
 
 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)