Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull powerpc fixes from Benjamin Herrenschmidt:
"Here are a few fixes for 3.6 that were piling up while I was away or
busy (I was mostly MIA a week or two before San Diego).
Some fixes from Anton fixing up issues with our relatively new DSCR
control feature, and a few other fixes that are either regressions or
bugs nasty enough to warrant not waiting."
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc: Don't use __put_user() in patch_instruction
powerpc: Make sure IPI handlers see data written by IPI senders
powerpc: Restore correct DSCR in context switch
powerpc: Fix DSCR inheritance in copy_thread()
powerpc: Keep thread.dscr and thread.dscr_inherit in sync
powerpc: Update DSCR on all CPUs when writing sysfs dscr_default
powerpc/powernv: Always go into nap mode when CPU is offline
powerpc: Give hypervisor decrementer interrupts their own handler
powerpc/vphn: Fix arch_update_cpu_topology() return value
diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index 53b6dfa..54b73a2 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -386,6 +386,7 @@
enum idle_boot_override {IDLE_NO_OVERRIDE = 0, IDLE_POWERSAVE_OFF};
extern int powersave_nap; /* set if nap mode can be used in idle loop */
+extern void power7_nap(void);
#ifdef CONFIG_PSERIES_IDLE
extern void update_smt_snooze_delay(int snooze);
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 85b05c4..e899572 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -76,6 +76,7 @@
DEFINE(SIGSEGV, SIGSEGV);
DEFINE(NMI_MASK, NMI_MASK);
DEFINE(THREAD_DSCR, offsetof(struct thread_struct, dscr));
+ DEFINE(THREAD_DSCR_INHERIT, offsetof(struct thread_struct, dscr_inherit));
#else
DEFINE(THREAD_INFO, offsetof(struct task_struct, stack));
#endif /* CONFIG_PPC64 */
diff --git a/arch/powerpc/kernel/dbell.c b/arch/powerpc/kernel/dbell.c
index 5b25c80..a892680 100644
--- a/arch/powerpc/kernel/dbell.c
+++ b/arch/powerpc/kernel/dbell.c
@@ -28,6 +28,8 @@
void doorbell_cause_ipi(int cpu, unsigned long data)
{
+ /* Order previous accesses vs. msgsnd, which is treated as a store */
+ mb();
ppc_msgsnd(PPC_DBELL, 0, data);
}
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 4b01a25..b40e0b4 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -370,6 +370,12 @@
li r3,0
b syscall_exit
+ .section ".toc","aw"
+DSCR_DEFAULT:
+ .tc dscr_default[TC],dscr_default
+
+ .section ".text"
+
/*
* This routine switches between two different tasks. The process
* state of one is saved on its kernel stack. Then the state
@@ -509,9 +515,6 @@
mr r1,r8 /* start using new stack pointer */
std r7,PACAKSAVE(r13)
- ld r6,_CCR(r1)
- mtcrf 0xFF,r6
-
#ifdef CONFIG_ALTIVEC
BEGIN_FTR_SECTION
ld r0,THREAD_VRSAVE(r4)
@@ -520,14 +523,22 @@
#endif /* CONFIG_ALTIVEC */
#ifdef CONFIG_PPC64
BEGIN_FTR_SECTION
+ lwz r6,THREAD_DSCR_INHERIT(r4)
+ ld r7,DSCR_DEFAULT@toc(2)
ld r0,THREAD_DSCR(r4)
- cmpd r0,r25
- beq 1f
+ cmpwi r6,0
+ bne 1f
+ ld r0,0(r7)
+1: cmpd r0,r25
+ beq 2f
mtspr SPRN_DSCR,r0
-1:
+2:
END_FTR_SECTION_IFSET(CPU_FTR_DSCR)
#endif
+ ld r6,_CCR(r1)
+ mtcrf 0xFF,r6
+
/* r3-r13 are destroyed -- Cort */
REST_8GPRS(14, r1)
REST_10GPRS(22, r1)
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index e894515..39aa97d 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -186,7 +186,7 @@
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x800)
MASKABLE_EXCEPTION_PSERIES(0x900, 0x900, decrementer)
- MASKABLE_EXCEPTION_HV(0x980, 0x982, decrementer)
+ STD_EXCEPTION_HV(0x980, 0x982, hdecrementer)
STD_EXCEPTION_PSERIES(0xa00, 0xa00, trap_0a)
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xa00)
@@ -486,6 +486,7 @@
STD_EXCEPTION_COMMON_ASYNC(0x500, hardware_interrupt, do_IRQ)
STD_EXCEPTION_COMMON_ASYNC(0x900, decrementer, .timer_interrupt)
+ STD_EXCEPTION_COMMON(0x980, hdecrementer, .hdec_interrupt)
STD_EXCEPTION_COMMON(0xa00, trap_0a, .unknown_exception)
STD_EXCEPTION_COMMON(0xb00, trap_0b, .unknown_exception)
STD_EXCEPTION_COMMON(0xd00, single_step, .single_step_exception)
diff --git a/arch/powerpc/kernel/idle_power7.S b/arch/powerpc/kernel/idle_power7.S
index 7140d83..e11863f 100644
--- a/arch/powerpc/kernel/idle_power7.S
+++ b/arch/powerpc/kernel/idle_power7.S
@@ -28,7 +28,9 @@
lwz r4,ADDROFF(powersave_nap)(r3)
cmpwi 0,r4,0
beqlr
+ /* fall through */
+_GLOBAL(power7_nap)
/* NAP is a state loss, we create a regs frame on the
* stack, fill it up with the state we care about and
* stick a pointer to it in PACAR1. We really only
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 710f400..1a1f2dd 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -802,16 +802,8 @@
#endif /* CONFIG_PPC_STD_MMU_64 */
#ifdef CONFIG_PPC64
if (cpu_has_feature(CPU_FTR_DSCR)) {
- if (current->thread.dscr_inherit) {
- p->thread.dscr_inherit = 1;
- p->thread.dscr = current->thread.dscr;
- } else if (0 != dscr_default) {
- p->thread.dscr_inherit = 1;
- p->thread.dscr = dscr_default;
- } else {
- p->thread.dscr_inherit = 0;
- p->thread.dscr = 0;
- }
+ p->thread.dscr_inherit = current->thread.dscr_inherit;
+ p->thread.dscr = current->thread.dscr;
}
#endif
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 0321007..8d4214a 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -198,8 +198,15 @@
struct cpu_messages *info = &per_cpu(ipi_message, cpu);
char *message = (char *)&info->messages;
+ /*
+ * Order previous accesses before accesses in the IPI handler.
+ */
+ smp_mb();
message[msg] = 1;
- mb();
+ /*
+ * cause_ipi functions are required to include a full barrier
+ * before doing whatever causes the IPI.
+ */
smp_ops->cause_ipi(cpu, info->data);
}
@@ -211,7 +218,7 @@
mb(); /* order any irq clear */
do {
- all = xchg_local(&info->messages, 0);
+ all = xchg(&info->messages, 0);
#ifdef __BIG_ENDIAN
if (all & (1 << (24 - 8 * PPC_MSG_CALL_FUNCTION)))
diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c
index 3529446..8302af6 100644
--- a/arch/powerpc/kernel/sysfs.c
+++ b/arch/powerpc/kernel/sysfs.c
@@ -194,6 +194,14 @@
return sprintf(buf, "%lx\n", dscr_default);
}
+static void update_dscr(void *dummy)
+{
+ if (!current->thread.dscr_inherit) {
+ current->thread.dscr = dscr_default;
+ mtspr(SPRN_DSCR, dscr_default);
+ }
+}
+
static ssize_t __used store_dscr_default(struct device *dev,
struct device_attribute *attr, const char *buf,
size_t count)
@@ -206,6 +214,8 @@
return -EINVAL;
dscr_default = val;
+ on_each_cpu(update_dscr, NULL, 1);
+
return count;
}
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index be171ee..e49e931 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -535,6 +535,15 @@
trace_timer_interrupt_exit(regs);
}
+/*
+ * Hypervisor decrementer interrupts shouldn't occur but are sometimes
+ * left pending on exit from a KVM guest. We don't need to do anything
+ * to clear them, as they are edge-triggered.
+ */
+void hdec_interrupt(struct pt_regs *regs)
+{
+}
+
#ifdef CONFIG_SUSPEND
static void generic_suspend_disable_irqs(void)
{
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 1589723..ae0843f 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -972,8 +972,9 @@
cpu_has_feature(CPU_FTR_DSCR)) {
PPC_WARN_EMULATED(mtdscr, regs);
rd = (instword >> 21) & 0x1f;
- mtspr(SPRN_DSCR, regs->gpr[rd]);
+ current->thread.dscr = regs->gpr[rd];
current->thread.dscr_inherit = 1;
+ mtspr(SPRN_DSCR, current->thread.dscr);
return 0;
}
#endif
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index dd223b3..17e5b23 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -20,7 +20,7 @@
{
int err;
- err = __put_user(instr, addr);
+ __put_user_size(instr, addr, 4, err);
if (err)
return err;
asm ("dcbst 0, %0; sync; icbi 0,%0; sync; isync" : : "r" (addr));
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 39b1597..59213cf 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -1436,11 +1436,11 @@
/*
* Update the node maps and sysfs entries for each cpu whose home node
- * has changed.
+ * has changed. Returns 1 when the topology has changed, and 0 otherwise.
*/
int arch_update_cpu_topology(void)
{
- int cpu, nid, old_nid;
+ int cpu, nid, old_nid, changed = 0;
unsigned int associativity[VPHN_ASSOC_BUFSIZE] = {0};
struct device *dev;
@@ -1466,9 +1466,10 @@
dev = get_cpu_device(cpu);
if (dev)
kobject_uevent(&dev->kobj, KOBJ_CHANGE);
+ changed = 1;
}
- return 1;
+ return changed;
}
static void topology_work_fn(struct work_struct *work)
diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c
index 3ef4625..7698b6e 100644
--- a/arch/powerpc/platforms/powernv/smp.c
+++ b/arch/powerpc/platforms/powernv/smp.c
@@ -106,14 +106,6 @@
{
unsigned int cpu;
- /* If powersave_nap is enabled, use NAP mode, else just
- * spin aimlessly
- */
- if (!powersave_nap) {
- generic_mach_cpu_die();
- return;
- }
-
/* Standard hot unplug procedure */
local_irq_disable();
idle_task_exit();
@@ -128,7 +120,7 @@
*/
mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~(u64)LPCR_PECE1);
while (!generic_check_cpu_restart(cpu)) {
- power7_idle();
+ power7_nap();
if (!generic_check_cpu_restart(cpu)) {
DBG("CPU%d Unexpected exit while offline !\n", cpu);
/* We may be getting an IPI, so we re-enable
diff --git a/arch/powerpc/sysdev/xics/icp-hv.c b/arch/powerpc/sysdev/xics/icp-hv.c
index 14469cf..df0fc58 100644
--- a/arch/powerpc/sysdev/xics/icp-hv.c
+++ b/arch/powerpc/sysdev/xics/icp-hv.c
@@ -65,7 +65,11 @@
static inline void icp_hv_set_qirr(int n_cpu , u8 value)
{
int hw_cpu = get_hard_smp_processor_id(n_cpu);
- long rc = plpar_hcall_norets(H_IPI, hw_cpu, value);
+ long rc;
+
+ /* Make sure all previous accesses are ordered before IPI sending */
+ mb();
+ rc = plpar_hcall_norets(H_IPI, hw_cpu, value);
if (rc != H_SUCCESS) {
pr_err("%s: bad return code qirr cpu=%d hw_cpu=%d mfrr=0x%x "
"returned %ld\n", __func__, n_cpu, hw_cpu, value, rc);