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authorMichael Ellerman <mpe@ellerman.id.au>2017-08-23 22:20:10 +1000
committerMichael Ellerman <mpe@ellerman.id.au>2017-08-23 22:20:10 +1000
commit15c659ff9d5b367c886166a9854a89b72c524a68 (patch)
treed33acaf62889bf6304f6109dd69923a17ab938be /arch
parentmacintosh/rack-meter: Make of_device_ids const (diff)
parentpowerpc/mm: Ensure cpumask update is ordered (diff)
downloadlinux-dev-15c659ff9d5b367c886166a9854a89b72c524a68.tar.xz
linux-dev-15c659ff9d5b367c886166a9854a89b72c524a68.zip
Merge branch 'fixes' into next
There's a non-trivial dependency between some commits we want to put in next and the KVM prefetch work around that went into fixes. So merge fixes into next.
Diffstat (limited to 'arch')
-rw-r--r--arch/powerpc/Makefile25
-rw-r--r--arch/powerpc/boot/Makefile14
-rw-r--r--arch/powerpc/configs/powernv_defconfig3
-rw-r--r--arch/powerpc/configs/ppc64_defconfig3
-rw-r--r--arch/powerpc/configs/pseries_defconfig3
-rw-r--r--arch/powerpc/include/asm/book3s/64/mmu.h15
-rw-r--r--arch/powerpc/include/asm/book3s/64/pgtable.h10
-rw-r--r--arch/powerpc/include/asm/mmu_context.h36
-rw-r--r--arch/powerpc/include/asm/pgtable-be-types.h1
-rw-r--r--arch/powerpc/include/asm/pgtable-types.h1
-rw-r--r--arch/powerpc/kernel/entry_64.S60
-rw-r--r--arch/powerpc/kernel/exceptions-64s.S10
-rw-r--r--arch/powerpc/kernel/idle_book3s.S8
-rw-r--r--arch/powerpc/kernel/irq.c15
-rw-r--r--arch/powerpc/kernel/process.c9
-rw-r--r--arch/powerpc/kernel/ptrace.c13
-rw-r--r--arch/powerpc/kernel/smp.c18
-rw-r--r--arch/powerpc/kernel/watchdog.c49
-rw-r--r--arch/powerpc/kvm/book3s_hv_rmhandlers.S59
-rw-r--r--arch/powerpc/mm/mmu_context_book3s64.c5
-rw-r--r--arch/powerpc/mm/pgtable-radix.c34
-rw-r--r--arch/powerpc/mm/subpage-prot.c2
-rw-r--r--arch/powerpc/mm/tlb-radix.c45
-rw-r--r--arch/powerpc/platforms/83xx/mpc832x_rdb.c2
-rw-r--r--arch/powerpc/platforms/powernv/idle.c41
-rw-r--r--arch/powerpc/platforms/powernv/pci-ioda.c8
-rw-r--r--arch/powerpc/platforms/pseries/reconfig.c1
27 files changed, 363 insertions, 127 deletions
diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 5480a7d45ef2..1381693a4a51 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -59,6 +59,19 @@ machine-$(CONFIG_PPC64) += 64
machine-$(CONFIG_CPU_LITTLE_ENDIAN) += le
UTS_MACHINE := $(subst $(space),,$(machine-y))
+# XXX This needs to be before we override LD below
+ifdef CONFIG_PPC32
+KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
+else
+ifeq ($(call ld-ifversion, -ge, 225000000, y),y)
+# Have the linker provide sfpr if possible.
+# There is a corresponding test in arch/powerpc/lib/Makefile
+KBUILD_LDFLAGS_MODULE += --save-restore-funcs
+else
+KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
+endif
+endif
+
ifeq ($(CONFIG_CPU_LITTLE_ENDIAN),y)
override LD += -EL
LDEMULATION := lppc
@@ -190,18 +203,6 @@ else
CHECKFLAGS += -D__LITTLE_ENDIAN__
endif
-ifdef CONFIG_PPC32
-KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
-else
-ifeq ($(call ld-ifversion, -ge, 225000000, y),y)
-# Have the linker provide sfpr if possible.
-# There is a corresponding test in arch/powerpc/lib/Makefile
-KBUILD_LDFLAGS_MODULE += --save-restore-funcs
-else
-KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
-endif
-endif
-
ifeq ($(CONFIG_476FPE_ERR46),y)
KBUILD_LDFLAGS_MODULE += --ppc476-workaround \
-T $(srctree)/arch/powerpc/platforms/44x/ppc476_modules.lds
diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
index bd2a1b8cd83f..8a437c5f6b01 100644
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile
@@ -25,12 +25,20 @@ compress-$(CONFIG_KERNEL_XZ) := CONFIG_KERNEL_XZ
BOOTCFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
-fno-strict-aliasing -Os -msoft-float -pipe \
-fomit-frame-pointer -fno-builtin -fPIC -nostdinc \
- -isystem $(shell $(CROSS32CC) -print-file-name=include) \
-D$(compress-y)
+BOOTCC := $(CC)
ifdef CONFIG_PPC64_BOOT_WRAPPER
BOOTCFLAGS += -m64
+else
+BOOTCFLAGS += -m32
+ifdef CROSS32_COMPILE
+ BOOTCC := $(CROSS32_COMPILE)gcc
+endif
endif
+
+BOOTCFLAGS += -isystem $(shell $(BOOTCC) -print-file-name=include)
+
ifdef CONFIG_CPU_BIG_ENDIAN
BOOTCFLAGS += -mbig-endian
else
@@ -183,10 +191,10 @@ clean-files := $(zlib-) $(zlibheader-) $(zliblinuxheader-) \
empty.c zImage.coff.lds zImage.ps3.lds zImage.lds
quiet_cmd_bootcc = BOOTCC $@
- cmd_bootcc = $(CROSS32CC) -Wp,-MD,$(depfile) $(BOOTCFLAGS) -c -o $@ $<
+ cmd_bootcc = $(BOOTCC) -Wp,-MD,$(depfile) $(BOOTCFLAGS) -c -o $@ $<
quiet_cmd_bootas = BOOTAS $@
- cmd_bootas = $(CROSS32CC) -Wp,-MD,$(depfile) $(BOOTAFLAGS) -c -o $@ $<
+ cmd_bootas = $(BOOTCC) -Wp,-MD,$(depfile) $(BOOTAFLAGS) -c -o $@ $<
quiet_cmd_bootar = BOOTAR $@
cmd_bootar = $(CROSS32AR) -cr$(KBUILD_ARFLAGS) $@.$$$$ $(filter-out FORCE,$^); mv $@.$$$$ $@
diff --git a/arch/powerpc/configs/powernv_defconfig b/arch/powerpc/configs/powernv_defconfig
index 0695ce047d56..34fc9bbfca9e 100644
--- a/arch/powerpc/configs/powernv_defconfig
+++ b/arch/powerpc/configs/powernv_defconfig
@@ -293,7 +293,8 @@ CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_KERNEL=y
CONFIG_DEBUG_STACK_USAGE=y
CONFIG_DEBUG_STACKOVERFLOW=y
-CONFIG_LOCKUP_DETECTOR=y
+CONFIG_SOFTLOCKUP_DETECTOR=y
+CONFIG_HARDLOCKUP_DETECTOR=y
CONFIG_LATENCYTOP=y
CONFIG_SCHED_TRACER=y
CONFIG_BLK_DEV_IO_TRACE=y
diff --git a/arch/powerpc/configs/ppc64_defconfig b/arch/powerpc/configs/ppc64_defconfig
index 5175028c56ce..c5246d29f385 100644
--- a/arch/powerpc/configs/ppc64_defconfig
+++ b/arch/powerpc/configs/ppc64_defconfig
@@ -324,7 +324,8 @@ CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_KERNEL=y
CONFIG_DEBUG_STACK_USAGE=y
CONFIG_DEBUG_STACKOVERFLOW=y
-CONFIG_LOCKUP_DETECTOR=y
+CONFIG_SOFTLOCKUP_DETECTOR=y
+CONFIG_HARDLOCKUP_DETECTOR=y
CONFIG_DEBUG_MUTEXES=y
CONFIG_LATENCYTOP=y
CONFIG_SCHED_TRACER=y
diff --git a/arch/powerpc/configs/pseries_defconfig b/arch/powerpc/configs/pseries_defconfig
index 1a61aa20dfba..fd5d98a0b95c 100644
--- a/arch/powerpc/configs/pseries_defconfig
+++ b/arch/powerpc/configs/pseries_defconfig
@@ -291,7 +291,8 @@ CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_KERNEL=y
CONFIG_DEBUG_STACK_USAGE=y
CONFIG_DEBUG_STACKOVERFLOW=y
-CONFIG_LOCKUP_DETECTOR=y
+CONFIG_SOFTLOCKUP_DETECTOR=y
+CONFIG_HARDLOCKUP_DETECTOR=y
CONFIG_LATENCYTOP=y
CONFIG_SCHED_TRACER=y
CONFIG_BLK_DEV_IO_TRACE=y
diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
index cbf1945f4338..1a220cdff923 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu.h
@@ -59,13 +59,14 @@ extern struct patb_entry *partition_tb;
#define PRTS_MASK 0x1f /* process table size field */
#define PRTB_MASK 0x0ffffffffffff000UL
-/*
- * Limit process table to PAGE_SIZE table. This
- * also limit the max pid we can support.
- * MAX_USER_CONTEXT * 16 bytes of space.
- */
-#define PRTB_SIZE_SHIFT (CONTEXT_BITS + 4)
-#define PRTB_ENTRIES (1ul << CONTEXT_BITS)
+/* Number of supported PID bits */
+extern unsigned int mmu_pid_bits;
+
+/* Base PID to allocate from */
+extern unsigned int mmu_base_pid;
+
+#define PRTB_SIZE_SHIFT (mmu_pid_bits + 4)
+#define PRTB_ENTRIES (1ul << mmu_pid_bits)
/*
* Power9 currently only support 64K partition table size.
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index a43c60aa1c2c..b9aff515b4de 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -614,9 +614,17 @@ 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)
diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index eb749c86dca5..2ab328f0159e 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -45,7 +45,7 @@ extern void set_context(unsigned long id, pgd_t *pgd);
#ifdef CONFIG_PPC_BOOK3S_64
extern void radix__switch_mmu_context(struct mm_struct *prev,
- struct mm_struct *next);
+ struct mm_struct *next);
static inline void switch_mmu_context(struct mm_struct *prev,
struct mm_struct *next,
struct task_struct *tsk)
@@ -67,6 +67,12 @@ extern void __destroy_context(unsigned long context_id);
extern void mmu_context_init(void);
#endif
+#if defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) && defined(CONFIG_PPC_RADIX_MMU)
+extern void radix_kvm_prefetch_workaround(struct mm_struct *mm);
+#else
+static inline void radix_kvm_prefetch_workaround(struct mm_struct *mm) { }
+#endif
+
extern void switch_cop(struct mm_struct *next);
extern int use_cop(unsigned long acop, struct mm_struct *mm);
extern void drop_cop(unsigned long acop, struct mm_struct *mm);
@@ -79,10 +85,32 @@ static inline void switch_mm_irqs_off(struct mm_struct *prev,
struct mm_struct *next,
struct task_struct *tsk)
{
+ bool new_on_cpu = false;
+
/* Mark this context has been used on the new CPU */
- if (!cpumask_test_cpu(smp_processor_id(), mm_cpumask(next)))
+ if (!cpumask_test_cpu(smp_processor_id(), mm_cpumask(next))) {
cpumask_set_cpu(smp_processor_id(), mm_cpumask(next));
+ /*
+ * This full barrier orders the store to the cpumask above vs
+ * a subsequent operation which allows this CPU to begin loading
+ * translations for next.
+ *
+ * When using the radix MMU that operation is the load of the
+ * MMU context id, which is then moved to SPRN_PID.
+ *
+ * For the hash MMU it is either the first load from slb_cache
+ * in switch_slb(), and/or the store of paca->mm_ctx_id in
+ * copy_mm_to_paca().
+ *
+ * On the read side the barrier is in pte_xchg(), which orders
+ * the store to the PTE vs the load of mm_cpumask.
+ */
+ smp_mb();
+
+ new_on_cpu = true;
+ }
+
/* 32-bit keeps track of the current PGDIR in the thread struct */
#ifdef CONFIG_PPC32
tsk->thread.pgdir = next->pgd;
@@ -103,6 +131,10 @@ static inline void switch_mm_irqs_off(struct mm_struct *prev,
if (cpu_has_feature(CPU_FTR_ALTIVEC))
asm volatile ("dssall");
#endif /* CONFIG_ALTIVEC */
+
+ if (new_on_cpu)
+ radix_kvm_prefetch_workaround(next);
+
/*
* The actual HW switching method differs between the various
* sub architectures. Out of line for now
diff --git a/arch/powerpc/include/asm/pgtable-be-types.h b/arch/powerpc/include/asm/pgtable-be-types.h
index 9c0f5db5cf46..67e7e3d990f4 100644
--- a/arch/powerpc/include/asm/pgtable-be-types.h
+++ b/arch/powerpc/include/asm/pgtable-be-types.h
@@ -87,6 +87,7 @@ static inline bool pte_xchg(pte_t *ptep, pte_t old, pte_t new)
unsigned long *p = (unsigned long *)ptep;
__be64 prev;
+ /* See comment in switch_mm_irqs_off() */
prev = (__force __be64)__cmpxchg_u64(p, (__force unsigned long)pte_raw(old),
(__force unsigned long)pte_raw(new));
diff --git a/arch/powerpc/include/asm/pgtable-types.h b/arch/powerpc/include/asm/pgtable-types.h
index 8bd3b13fe2fb..369a164b545c 100644
--- a/arch/powerpc/include/asm/pgtable-types.h
+++ b/arch/powerpc/include/asm/pgtable-types.h
@@ -62,6 +62,7 @@ static inline bool pte_xchg(pte_t *ptep, pte_t old, pte_t new)
{
unsigned long *p = (unsigned long *)ptep;
+ /* See comment in switch_mm_irqs_off() */
return pte_val(old) == __cmpxchg_u64(p, pte_val(old), pte_val(new));
}
#endif
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 49d8422767b4..e925c1c99c71 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -223,17 +223,27 @@ system_call_exit:
andi. r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)
bne- .Lsyscall_exit_work
- /* If MSR_FP and MSR_VEC are set in user msr, then no need to restore */
- li r7,MSR_FP
+ andi. r0,r8,MSR_FP
+ beq 2f
#ifdef CONFIG_ALTIVEC
- oris r7,r7,MSR_VEC@h
+ andis. r0,r8,MSR_VEC@h
+ bne 3f
#endif
- and r0,r8,r7
- cmpd r0,r7
- bne .Lsyscall_restore_math
-.Lsyscall_restore_math_cont:
+2: addi r3,r1,STACK_FRAME_OVERHEAD
+#ifdef CONFIG_PPC_BOOK3S
+ li r10,MSR_RI
+ mtmsrd r10,1 /* Restore RI */
+#endif
+ bl restore_math
+#ifdef CONFIG_PPC_BOOK3S
+ li r11,0
+ mtmsrd r11,1
+#endif
+ ld r8,_MSR(r1)
+ ld r3,RESULT(r1)
+ li r11,-MAX_ERRNO
- cmpld r3,r11
+3: cmpld r3,r11
ld r5,_CCR(r1)
bge- .Lsyscall_error
.Lsyscall_error_cont:
@@ -267,40 +277,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
std r5,_CCR(r1)
b .Lsyscall_error_cont
-.Lsyscall_restore_math:
- /*
- * Some initial tests from restore_math to avoid the heavyweight
- * C code entry and MSR manipulations.
- */
- LOAD_REG_IMMEDIATE(r0, MSR_TS_MASK)
- and. r0,r0,r8
- bne 1f
-
- ld r7,PACACURRENT(r13)
- lbz r0,THREAD+THREAD_LOAD_FP(r7)
-#ifdef CONFIG_ALTIVEC
- lbz r6,THREAD+THREAD_LOAD_VEC(r7)
- add r0,r0,r6
-#endif
- cmpdi r0,0
- beq .Lsyscall_restore_math_cont
-
-1: addi r3,r1,STACK_FRAME_OVERHEAD
-#ifdef CONFIG_PPC_BOOK3S
- li r10,MSR_RI
- mtmsrd r10,1 /* Restore RI */
-#endif
- bl restore_math
-#ifdef CONFIG_PPC_BOOK3S
- li r11,0
- mtmsrd r11,1
-#endif
- /* Restore volatiles, reload MSR from updated one */
- ld r8,_MSR(r1)
- ld r3,RESULT(r1)
- li r11,-MAX_ERRNO
- b .Lsyscall_restore_math_cont
-
/* Traced system call support */
.Lsyscall_dotrace:
bl save_nvgprs
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index a42308b2187b..e66cbb1c6bc2 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -1325,10 +1325,18 @@ EXC_VIRT_NONE(0x5800, 0x100)
std r10,PACA_EXGEN+EX_R13(r13); \
EXCEPTION_PROLOG_PSERIES_1(soft_nmi_common, _H)
+/*
+ * Branch to soft_nmi_interrupt using the emergency stack. The emergency
+ * stack is one that is usable by maskable interrupts so long as MSR_EE
+ * remains off. It is used for recovery when something has corrupted the
+ * normal kernel stack, for example. The "soft NMI" must not use the process
+ * stack because we want irq disabled sections to avoid touching the stack
+ * at all (other than PMU interrupts), so use the emergency stack for this,
+ * and run it entirely with interrupts hard disabled.
+ */
EXC_COMMON_BEGIN(soft_nmi_common)
mr r10,r1
ld r1,PACAEMERGSP(r13)
- ld r1,PACA_NMI_EMERG_SP(r13)
subi r1,r1,INT_FRAME_SIZE
EXCEPTION_COMMON_NORET_STACK(PACA_EXGEN, 0x900,
system_reset, soft_nmi_interrupt,
diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S
index 4621568277f2..bfbf0976fc09 100644
--- a/arch/powerpc/kernel/idle_book3s.S
+++ b/arch/powerpc/kernel/idle_book3s.S
@@ -514,11 +514,17 @@ pnv_restore_hyp_resource_arch300:
/*
* Workaround for POWER9, if we lost resources, the ERAT
* might have been mixed up and needs flushing. We also need
- * to reload MMCR0 (see comment above).
+ * to reload MMCR0 (see comment above). We also need to set
+ * then clear bit 60 in MMCRA to ensure the PMU starts running.
*/
blt cr3,1f
PPC_INVALIDATE_ERAT
ld r1,PACAR1(r13)
+ mfspr r4,SPRN_MMCRA
+ ori r4,r4,(1 << (63-60))
+ mtspr SPRN_MMCRA,r4
+ xori r4,r4,(1 << (63-60))
+ mtspr SPRN_MMCRA,r4
ld r4,_MMCR0(r1)
mtspr SPRN_MMCR0,r4
1:
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index 8b514e910bf1..da6d22ab180e 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -145,6 +145,19 @@ notrace unsigned int __check_irq_replay(void)
/* Clear bit 0 which we wouldn't clear otherwise */
local_paca->irq_happened &= ~PACA_IRQ_HARD_DIS;
+ if (happened & PACA_IRQ_HARD_DIS) {
+ /*
+ * We may have missed a decrementer interrupt if hard disabled.
+ * Check the decrementer register in case we had a rollover
+ * while hard disabled.
+ */
+ if (!(happened & PACA_IRQ_DEC)) {
+ if (decrementer_check_overflow()) {
+ local_paca->irq_happened |= PACA_IRQ_DEC;
+ happened |= PACA_IRQ_DEC;
+ }
+ }
+ }
/*
* Force the delivery of pending soft-disabled interrupts on PS3.
@@ -170,7 +183,7 @@ notrace unsigned int __check_irq_replay(void)
* in case we also had a rollover while hard disabled
*/
local_paca->irq_happened &= ~PACA_IRQ_DEC;
- if ((happened & PACA_IRQ_DEC) || decrementer_check_overflow())
+ if (happened & PACA_IRQ_DEC)
return 0x900;
/* Finally check if an external interrupt happened */
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index cc5bae4bba7b..34bd94b090e2 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -363,7 +363,8 @@ void enable_kernel_vsx(void)
cpumsr = msr_check_and_set(MSR_FP|MSR_VEC|MSR_VSX);
- if (current->thread.regs && (current->thread.regs->msr & MSR_VSX)) {
+ if (current->thread.regs &&
+ (current->thread.regs->msr & (MSR_VSX|MSR_VEC|MSR_FP))) {
check_if_tm_restore_required(current);
/*
* If a thread has already been reclaimed then the
@@ -383,7 +384,7 @@ void flush_vsx_to_thread(struct task_struct *tsk)
{
if (tsk->thread.regs) {
preempt_disable();
- if (tsk->thread.regs->msr & MSR_VSX) {
+ if (tsk->thread.regs->msr & (MSR_VSX|MSR_VEC|MSR_FP)) {
BUG_ON(tsk != current);
giveup_vsx(tsk);
}
@@ -505,10 +506,6 @@ void restore_math(struct pt_regs *regs)
{
unsigned long msr;
- /*
- * Syscall exit makes a similar initial check before branching
- * to restore_math. Keep them in synch.
- */
if (!msr_tm_active(regs->msr) &&
!current->thread.load_fp && !loadvec(current->thread))
return;
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index 925a4ef90559..660ed39e9c9a 100644
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -127,12 +127,19 @@ static void flush_tmregs_to_thread(struct task_struct *tsk)
* If task is not current, it will have been flushed already to
* it's thread_struct during __switch_to().
*
- * A reclaim flushes ALL the state.
+ * A reclaim flushes ALL the state or if not in TM save TM SPRs
+ * in the appropriate thread structures from live.
*/
- if (tsk == current && MSR_TM_SUSPENDED(mfmsr()))
- tm_reclaim_current(TM_CAUSE_SIGNAL);
+ if (tsk != current)
+ return;
+ if (MSR_TM_SUSPENDED(mfmsr())) {
+ tm_reclaim_current(TM_CAUSE_SIGNAL);
+ } else {
+ tm_enable();
+ tm_save_sprs(&(tsk->thread));
+ }
}
#else
static inline void flush_tmregs_to_thread(struct task_struct *tsk) { }
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 997c88d54acf..8d3320562c70 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -351,7 +351,7 @@ static void nmi_ipi_lock_start(unsigned long *flags)
hard_irq_disable();
while (atomic_cmpxchg(&__nmi_ipi_lock, 0, 1) == 1) {
raw_local_irq_restore(*flags);
- cpu_relax();
+ spin_until_cond(atomic_read(&__nmi_ipi_lock) == 0);
raw_local_irq_save(*flags);
hard_irq_disable();
}
@@ -360,7 +360,7 @@ static void nmi_ipi_lock_start(unsigned long *flags)
static void nmi_ipi_lock(void)
{
while (atomic_cmpxchg(&__nmi_ipi_lock, 0, 1) == 1)
- cpu_relax();
+ spin_until_cond(atomic_read(&__nmi_ipi_lock) == 0);
}
static void nmi_ipi_unlock(void)
@@ -475,7 +475,7 @@ int smp_send_nmi_ipi(int cpu, void (*fn)(struct pt_regs *), u64 delay_us)
nmi_ipi_lock_start(&flags);
while (nmi_ipi_busy_count) {
nmi_ipi_unlock_end(&flags);
- cpu_relax();
+ spin_until_cond(nmi_ipi_busy_count == 0);
nmi_ipi_lock_start(&flags);
}
@@ -1003,21 +1003,13 @@ static struct sched_domain_topology_level powerpc_topology[] = {
{ NULL, },
};
-static __init long smp_setup_cpu_workfn(void *data __always_unused)
-{
- smp_ops->setup_cpu(boot_cpuid);
- return 0;
-}
-
void __init smp_cpus_done(unsigned int max_cpus)
{
/*
- * We want the setup_cpu() here to be called on the boot CPU, but
- * init might run on any CPU, so make sure it's invoked on the boot
- * CPU.
+ * We are running pinned to the boot CPU, see rest_init().
*/
if (smp_ops && smp_ops->setup_cpu)
- work_on_cpu_safe(boot_cpuid, smp_setup_cpu_workfn, NULL);
+ smp_ops->setup_cpu(boot_cpuid);
if (smp_ops && smp_ops->bringup_done)
smp_ops->bringup_done();
diff --git a/arch/powerpc/kernel/watchdog.c b/arch/powerpc/kernel/watchdog.c
index 4b9a567c9975..2f6eadd9408d 100644
--- a/arch/powerpc/kernel/watchdog.c
+++ b/arch/powerpc/kernel/watchdog.c
@@ -71,15 +71,20 @@ static inline void wd_smp_lock(unsigned long *flags)
* This may be called from low level interrupt handlers at some
* point in future.
*/
- local_irq_save(*flags);
- while (unlikely(test_and_set_bit_lock(0, &__wd_smp_lock)))
- cpu_relax();
+ raw_local_irq_save(*flags);
+ hard_irq_disable(); /* Make it soft-NMI safe */
+ while (unlikely(test_and_set_bit_lock(0, &__wd_smp_lock))) {
+ raw_local_irq_restore(*flags);
+ spin_until_cond(!test_bit(0, &__wd_smp_lock));
+ raw_local_irq_save(*flags);
+ hard_irq_disable();
+ }
}
static inline void wd_smp_unlock(unsigned long *flags)
{
clear_bit_unlock(0, &__wd_smp_lock);
- local_irq_restore(*flags);
+ raw_local_irq_restore(*flags);
}
static void wd_lockup_ipi(struct pt_regs *regs)
@@ -96,10 +101,10 @@ static void wd_lockup_ipi(struct pt_regs *regs)
nmi_panic(regs, "Hard LOCKUP");
}
-static void set_cpu_stuck(int cpu, u64 tb)
+static void set_cpumask_stuck(const struct cpumask *cpumask, u64 tb)
{
- cpumask_set_cpu(cpu, &wd_smp_cpus_stuck);
- cpumask_clear_cpu(cpu, &wd_smp_cpus_pending);
+ cpumask_or(&wd_smp_cpus_stuck, &wd_smp_cpus_stuck, cpumask);
+ cpumask_andnot(&wd_smp_cpus_pending, &wd_smp_cpus_pending, cpumask);
if (cpumask_empty(&wd_smp_cpus_pending)) {
wd_smp_last_reset_tb = tb;
cpumask_andnot(&wd_smp_cpus_pending,
@@ -107,6 +112,10 @@ static void set_cpu_stuck(int cpu, u64 tb)
&wd_smp_cpus_stuck);
}
}
+static void set_cpu_stuck(int cpu, u64 tb)
+{
+ set_cpumask_stuck(cpumask_of(cpu), tb);
+}
static void watchdog_smp_panic(int cpu, u64 tb)
{
@@ -135,11 +144,9 @@ static void watchdog_smp_panic(int cpu, u64 tb)
}
smp_flush_nmi_ipi(1000000);
- /* Take the stuck CPU out of the watch group */
- for_each_cpu(c, &wd_smp_cpus_pending)
- set_cpu_stuck(c, tb);
+ /* Take the stuck CPUs out of the watch group */
+ set_cpumask_stuck(&wd_smp_cpus_pending, tb);
-out:
wd_smp_unlock(&flags);
printk_safe_flush();
@@ -152,6 +159,11 @@ out:
if (hardlockup_panic)
nmi_panic(NULL, "Hard LOCKUP");
+
+ return;
+
+out:
+ wd_smp_unlock(&flags);
}
static void wd_smp_clear_cpu_pending(int cpu, u64 tb)
@@ -261,9 +273,11 @@ static void wd_timer_fn(unsigned long data)
void arch_touch_nmi_watchdog(void)
{
+ unsigned long ticks = tb_ticks_per_usec * wd_timer_period_ms * 1000;
int cpu = smp_processor_id();
- watchdog_timer_interrupt(cpu);
+ if (get_tb() - per_cpu(wd_timer_tb, cpu) >= ticks)
+ watchdog_timer_interrupt(cpu);
}
EXPORT_SYMBOL(arch_touch_nmi_watchdog);
@@ -286,6 +300,8 @@ static void stop_watchdog_timer_on(unsigned int cpu)
static int start_wd_on_cpu(unsigned int cpu)
{
+ unsigned long flags;
+
if (cpumask_test_cpu(cpu, &wd_cpus_enabled)) {
WARN_ON(1);
return 0;
@@ -300,12 +316,14 @@ static int start_wd_on_cpu(unsigned int cpu)
if (!cpumask_test_cpu(cpu, &watchdog_cpumask))
return 0;
+ wd_smp_lock(&flags);
cpumask_set_cpu(cpu, &wd_cpus_enabled);
if (cpumask_weight(&wd_cpus_enabled) == 1) {
cpumask_set_cpu(cpu, &wd_smp_cpus_pending);
wd_smp_last_reset_tb = get_tb();
}
- smp_wmb();
+ wd_smp_unlock(&flags);
+
start_watchdog_timer_on(cpu);
return 0;
@@ -313,12 +331,17 @@ static int start_wd_on_cpu(unsigned int cpu)
static int stop_wd_on_cpu(unsigned int cpu)
{
+ unsigned long flags;
+
if (!cpumask_test_cpu(cpu, &wd_cpus_enabled))
return 0; /* Can happen in CPU unplug case */
stop_watchdog_timer_on(cpu);
+ wd_smp_lock(&flags);
cpumask_clear_cpu(cpu, &wd_cpus_enabled);
+ wd_smp_unlock(&flags);
+
wd_smp_clear_cpu_pending(cpu, get_tb());
return 0;
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index cb44065e2946..c52184a8efdf 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -1443,12 +1443,14 @@ mc_cont:
ori r6,r6,1
mtspr SPRN_CTRLT,r6
4:
- /* Read the guest SLB and save it away */
+ /* Check if we are running hash or radix and store it in cr2 */
ld r5, VCPU_KVM(r9)
lbz r0, KVM_RADIX(r5)
- cmpwi r0, 0
+ cmpwi cr2,r0,0
+
+ /* Read the guest SLB and save it away */
li r5, 0
- bne 3f /* for radix, save 0 entries */
+ bne cr2, 3f /* for radix, save 0 entries */
lwz r0,VCPU_SLB_NR(r9) /* number of entries in SLB */
mtctr r0
li r6,0
@@ -1712,11 +1714,6 @@ BEGIN_FTR_SECTION_NESTED(96)
END_FTR_SECTION_NESTED(CPU_FTR_ARCH_300, 0, 96)
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
22:
- /* Clear out SLB */
- li r5,0
- slbmte r5,r5
- slbia
- ptesync
/* Restore host values of some registers */
BEGIN_FTR_SECTION
@@ -1737,10 +1734,56 @@ BEGIN_FTR_SECTION
mtspr SPRN_PID, r7
mtspr SPRN_IAMR, r8
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
+
+#ifdef CONFIG_PPC_RADIX_MMU
+ /*
+ * Are we running hash or radix ?
+ */
+ beq cr2,3f
+
+ /* Radix: Handle the case where the guest used an illegal PID */
+ LOAD_REG_ADDR(r4, mmu_base_pid)
+ lwz r3, VCPU_GUEST_PID(r9)
+ lwz r5, 0(r4)
+ cmpw cr0,r3,r5
+ blt 2f
+
+ /*
+ * Illegal PID, the HW might have prefetched and cached in the TLB
+ * some translations for the LPID 0 / guest PID combination which
+ * Linux doesn't know about, so we need to flush that PID out of
+ * the TLB. First we need to set LPIDR to 0 so tlbiel applies to
+ * the right context.
+ */
+ li r0,0
+ mtspr SPRN_LPID,r0
+ isync
+
+ /* Then do a congruence class local flush */
+ ld r6,VCPU_KVM(r9)
+ lwz r0,KVM_TLB_SETS(r6)
+ mtctr r0
+ li r7,0x400 /* IS field = 0b01 */
+ ptesync
+ sldi r0,r3,32 /* RS has PID */
+1: PPC_TLBIEL(7,0,2,1,1) /* RIC=2, PRS=1, R=1 */
+ addi r7,r7,0x1000
+ bdnz 1b
+ ptesync
+
+2: /* Flush the ERAT on radix P9 DD1 guest exit */
BEGIN_FTR_SECTION
PPC_INVALIDATE_ERAT
END_FTR_SECTION_IFSET(CPU_FTR_POWER9_DD1)
+ b 4f
+#endif /* CONFIG_PPC_RADIX_MMU */
+ /* Hash: clear out SLB */
+3: li r5,0
+ slbmte r5,r5
+ slbia
+ ptesync
+4:
/*
* POWER7/POWER8 guest -> host partition switch code.
* We don't have to lock against tlbies but we do
diff --git a/arch/powerpc/mm/mmu_context_book3s64.c b/arch/powerpc/mm/mmu_context_book3s64.c
index db9d8cb0f8ee..60188f4b3ecd 100644
--- a/arch/powerpc/mm/mmu_context_book3s64.c
+++ b/arch/powerpc/mm/mmu_context_book3s64.c
@@ -124,9 +124,10 @@ static int hash__init_new_context(struct mm_struct *mm)
static int radix__init_new_context(struct mm_struct *mm)
{
unsigned long rts_field;
- int index;
+ int index, max_id;
- index = alloc_context_id(1, PRTB_ENTRIES - 1);
+ max_id = (1 << mmu_pid_bits) - 1;
+ index = alloc_context_id(mmu_base_pid, max_id);
if (index < 0)
return index;
diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c
index 1ee5452daf3a..c85e963d4893 100644
--- a/arch/powerpc/mm/pgtable-radix.c
+++ b/arch/powerpc/mm/pgtable-radix.c
@@ -25,6 +25,9 @@
#include <trace/events/thp.h>
+unsigned int mmu_pid_bits;
+unsigned int mmu_base_pid;
+
static int native_register_process_table(unsigned long base, unsigned long pg_sz,
unsigned long table_size)
{
@@ -265,11 +268,34 @@ static void __init radix_init_pgtable(void)
for_each_memblock(memory, reg)
WARN_ON(create_physical_mapping(reg->base,
reg->base + reg->size));
+
+ /* Find out how many PID bits are supported */
+ if (cpu_has_feature(CPU_FTR_HVMODE)) {
+ if (!mmu_pid_bits)
+ mmu_pid_bits = 20;
+#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+ /*
+ * When KVM is possible, we only use the top half of the
+ * PID space to avoid collisions between host and guest PIDs
+ * which can cause problems due to prefetch when exiting the
+ * guest with AIL=3
+ */
+ mmu_base_pid = 1 << (mmu_pid_bits - 1);
+#else
+ mmu_base_pid = 1;
+#endif
+ } else {
+ /* The guest uses the bottom half of the PID space */
+ if (!mmu_pid_bits)
+ mmu_pid_bits = 19;
+ mmu_base_pid = 1;
+ }
+
/*
* Allocate Partition table and process table for the
* host.
*/
- BUILD_BUG_ON_MSG((PRTB_SIZE_SHIFT > 36), "Process table size too large.");
+ BUG_ON(PRTB_SIZE_SHIFT > 36);
process_tb = early_alloc_pgtable(1UL << PRTB_SIZE_SHIFT);
/*
* Fill in the process table.
@@ -343,6 +369,12 @@ static int __init radix_dt_scan_page_sizes(unsigned long node,
if (type == NULL || strcmp(type, "cpu") != 0)
return 0;
+ /* Find MMU PID size */
+ prop = of_get_flat_dt_prop(node, "ibm,mmu-pid-bits", &size);
+ if (prop && size == 4)
+ mmu_pid_bits = be32_to_cpup(prop);
+
+ /* Grab page size encodings */
prop = of_get_flat_dt_prop(node, "ibm,processor-radix-AP-encodings", &size);
if (!prop)
return 0;
diff --git a/arch/powerpc/mm/subpage-prot.c b/arch/powerpc/mm/subpage-prot.c
index e94fbd4c8845..781532d7bc4d 100644
--- a/arch/powerpc/mm/subpage-prot.c
+++ b/arch/powerpc/mm/subpage-prot.c
@@ -36,7 +36,7 @@ void subpage_prot_free(struct mm_struct *mm)
}
}
addr = 0;
- for (i = 0; i < 2; ++i) {
+ for (i = 0; i < (TASK_SIZE_USER64 >> 43); ++i) {
p = spt->protptrs[i];
if (!p)
continue;
diff --git a/arch/powerpc/mm/tlb-radix.c b/arch/powerpc/mm/tlb-radix.c
index 18151e9ad694..b3e849c4886e 100644
--- a/arch/powerpc/mm/tlb-radix.c
+++ b/arch/powerpc/mm/tlb-radix.c
@@ -12,12 +12,12 @@
#include <linux/mm.h>
#include <linux/hugetlb.h>
#include <linux/memblock.h>
-#include <asm/ppc-opcode.h>
+#include <asm/ppc-opcode.h>
#include <asm/tlb.h>
#include <asm/tlbflush.h>
#include <asm/trace.h>
-
+#include <asm/cputhreads.h>
#define RIC_FLUSH_TLB 0
#define RIC_FLUSH_PWC 1
@@ -478,3 +478,44 @@ void radix__flush_tlb_pte_p9_dd1(unsigned long old_pte, struct mm_struct *mm,
else
radix__flush_tlb_page_psize(mm, address, mmu_virtual_psize);
}
+
+#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+extern void radix_kvm_prefetch_workaround(struct mm_struct *mm)
+{
+ unsigned int pid = mm->context.id;
+
+ if (unlikely(pid == MMU_NO_CONTEXT))
+ return;
+
+ /*
+ * If this context hasn't run on that CPU before and KVM is
+ * around, there's a slim chance that the guest on another
+ * CPU just brought in obsolete translation into the TLB of
+ * this CPU due to a bad prefetch using the guest PID on
+ * the way into the hypervisor.
+ *
+ * We work around this here. If KVM is possible, we check if
+ * any sibling thread is in KVM. If it is, the window may exist
+ * and thus we flush that PID from the core.
+ *
+ * A potential future improvement would be to mark which PIDs
+ * have never been used on the system and avoid it if the PID
+ * is new and the process has no other cpumask bit set.
+ */
+ if (cpu_has_feature(CPU_FTR_HVMODE) && radix_enabled()) {
+ int cpu = smp_processor_id();
+ int sib = cpu_first_thread_sibling(cpu);
+ bool flush = false;
+
+ for (; sib <= cpu_last_thread_sibling(cpu) && !flush; sib++) {
+ if (sib == cpu)
+ continue;
+ if (paca[sib].kvm_hstate.kvm_vcpu)
+ flush = true;
+ }
+ if (flush)
+ _tlbiel_pid(pid, RIC_FLUSH_ALL);
+ }
+}
+EXPORT_SYMBOL_GPL(radix_kvm_prefetch_workaround);
+#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
diff --git a/arch/powerpc/platforms/83xx/mpc832x_rdb.c b/arch/powerpc/platforms/83xx/mpc832x_rdb.c
index d7c9b186954d..763ffca9628d 100644
--- a/arch/powerpc/platforms/83xx/mpc832x_rdb.c
+++ b/arch/powerpc/platforms/83xx/mpc832x_rdb.c
@@ -89,7 +89,7 @@ static int __init of_fsl_spi_probe(char *type, char *compatible, u32 sysclk,
goto err;
ret = of_irq_to_resource(np, 0, &res[1]);
- if (!ret)
+ if (ret <= 0)
goto err;
pdev = platform_device_alloc("mpc83xx_spi", i);
diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c
index a1296e72cd2e..9f59041a172b 100644
--- a/arch/powerpc/platforms/powernv/idle.c
+++ b/arch/powerpc/platforms/powernv/idle.c
@@ -56,6 +56,7 @@ u64 pnv_first_deep_stop_state = MAX_STOP_STATE;
*/
static u64 pnv_deepest_stop_psscr_val;
static u64 pnv_deepest_stop_psscr_mask;
+static u64 pnv_deepest_stop_flag;
static bool deepest_stop_found;
static int pnv_save_sprs_for_deep_states(void)
@@ -185,8 +186,40 @@ static void pnv_alloc_idle_core_states(void)
update_subcore_sibling_mask();
- if (supported_cpuidle_states & OPAL_PM_LOSE_FULL_CONTEXT)
- pnv_save_sprs_for_deep_states();
+ if (supported_cpuidle_states & OPAL_PM_LOSE_FULL_CONTEXT) {
+ int rc = pnv_save_sprs_for_deep_states();
+
+ if (likely(!rc))
+ return;
+
+ /*
+ * The stop-api is unable to restore hypervisor
+ * resources on wakeup from platform idle states which
+ * lose full context. So disable such states.
+ */
+ supported_cpuidle_states &= ~OPAL_PM_LOSE_FULL_CONTEXT;
+ pr_warn("cpuidle-powernv: Disabling idle states that lose full context\n");
+ pr_warn("cpuidle-powernv: Idle power-savings, CPU-Hotplug affected\n");
+
+ if (cpu_has_feature(CPU_FTR_ARCH_300) &&
+ (pnv_deepest_stop_flag & OPAL_PM_LOSE_FULL_CONTEXT)) {
+ /*
+ * Use the default stop state for CPU-Hotplug
+ * if available.
+ */
+ if (default_stop_found) {
+ pnv_deepest_stop_psscr_val =
+ pnv_default_stop_val;
+ pnv_deepest_stop_psscr_mask =
+ pnv_default_stop_mask;
+ pr_warn("cpuidle-powernv: Offlined CPUs will stop with psscr = 0x%016llx\n",
+ pnv_deepest_stop_psscr_val);
+ } else { /* Fallback to snooze loop for CPU-Hotplug */
+ deepest_stop_found = false;
+ pr_warn("cpuidle-powernv: Offlined CPUs will busy wait\n");
+ }
+ }
+ }
}
u32 pnv_get_supported_cpuidle_states(void)
@@ -397,7 +430,8 @@ unsigned long pnv_cpu_offline(unsigned int cpu)
pnv_deepest_stop_psscr_val;
srr1 = power9_idle_stop(psscr);
- } else if (idle_states & OPAL_PM_WINKLE_ENABLED) {
+ } else if ((idle_states & OPAL_PM_WINKLE_ENABLED) &&
+ (idle_states & OPAL_PM_LOSE_FULL_CONTEXT)) {
srr1 = power7_idle_insn(PNV_THREAD_WINKLE);
} else if ((idle_states & OPAL_PM_SLEEP_ENABLED) ||
(idle_states & OPAL_PM_SLEEP_ENABLED_ER1)) {
@@ -585,6 +619,7 @@ static int __init pnv_power9_idle_init(struct device_node *np, u32 *flags,
max_residency_ns = residency_ns[i];
pnv_deepest_stop_psscr_val = psscr_val[i];
pnv_deepest_stop_psscr_mask = psscr_mask[i];
+ pnv_deepest_stop_flag = flags[i];
deepest_stop_found = true;
}
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 026a06c51458..48de308224d6 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -1851,6 +1851,14 @@ static int pnv_pci_ioda_dma_set_mask(struct pci_dev *pdev, u64 dma_mask)
/* 4GB offset bypasses 32-bit space */
set_dma_offset(&pdev->dev, (1ULL << 32));
set_dma_ops(&pdev->dev, &dma_direct_ops);
+ } else if (dma_mask >> 32 && dma_mask != DMA_BIT_MASK(64)) {
+ /*
+ * Fail the request if a DMA mask between 32 and 64 bits
+ * was requested but couldn't be fulfilled. Ideally we
+ * would do this for 64-bits but historically we have
+ * always fallen back to 32-bits.
+ */
+ return -ENOMEM;
} else {
dev_info(&pdev->dev, "Using 32-bit DMA via iommu\n");
set_dma_ops(&pdev->dev, &dma_iommu_ops);
diff --git a/arch/powerpc/platforms/pseries/reconfig.c b/arch/powerpc/platforms/pseries/reconfig.c
index e6bfff8a20a4..296c188fd5ca 100644
--- a/arch/powerpc/platforms/pseries/reconfig.c
+++ b/arch/powerpc/platforms/pseries/reconfig.c
@@ -82,7 +82,6 @@ static int pSeries_reconfig_remove_node(struct device_node *np)
of_detach_node(np);
of_node_put(parent);
- of_node_put(np); /* Must decrement the refcount */
return 0;
}