Merge tag 'powerpc-4.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"A fix for a bad bug (written by me) in our livepatch handler. Removal
of an over-zealous lockdep_assert_cpus_held() in our topology code. A
fix to the recently added emulation of cntlz[wd]. And three small
fixes to the recently added IMC PMU driver.
Thanks to: Anju T Sudhakar, Balbir Singh, Kamalesh Babulal, Naveen N.
Rao, Sandipan Das, Santosh Sivaraj, Thiago Jung Bauermann"
* tag 'powerpc-4.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/perf: Fix IMC initialization crash
powerpc/perf: Add ___GFP_NOWARN flag to alloc_pages_node()
powerpc/perf: Fix for core/nest imc call trace on cpuhotplug
powerpc: Don't call lockdep_assert_cpus_held() from arch_update_cpu_topology()
powerpc/lib/sstep: Fix count leading zeros instructions
powerpc/livepatch: Fix livepatch stack access
diff --git a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
index c98e90b..b4e2b71 100644
--- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
+++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
@@ -181,34 +181,25 @@
* - we have no stack frame and can not allocate one
* - LR points back to the original caller (in A)
* - CTR holds the new NIP in C
- * - r0 & r12 are free
- *
- * r0 can't be used as the base register for a DS-form load or store, so
- * we temporarily shuffle r1 (stack pointer) into r0 and then put it back.
+ * - r0, r11 & r12 are free
*/
livepatch_handler:
CURRENT_THREAD_INFO(r12, r1)
- /* Save stack pointer into r0 */
- mr r0, r1
-
/* Allocate 3 x 8 bytes */
- ld r1, TI_livepatch_sp(r12)
- addi r1, r1, 24
- std r1, TI_livepatch_sp(r12)
+ ld r11, TI_livepatch_sp(r12)
+ addi r11, r11, 24
+ std r11, TI_livepatch_sp(r12)
/* Save toc & real LR on livepatch stack */
- std r2, -24(r1)
+ std r2, -24(r11)
mflr r12
- std r12, -16(r1)
+ std r12, -16(r11)
/* Store stack end marker */
lis r12, STACK_END_MAGIC@h
ori r12, r12, STACK_END_MAGIC@l
- std r12, -8(r1)
-
- /* Restore real stack pointer */
- mr r1, r0
+ std r12, -8(r11)
/* Put ctr in r12 for global entry and branch there */
mfctr r12
@@ -216,36 +207,30 @@
/*
* Now we are returning from the patched function to the original
- * caller A. We are free to use r0 and r12, and we can use r2 until we
+ * caller A. We are free to use r11, r12 and we can use r2 until we
* restore it.
*/
CURRENT_THREAD_INFO(r12, r1)
- /* Save stack pointer into r0 */
- mr r0, r1
-
- ld r1, TI_livepatch_sp(r12)
+ ld r11, TI_livepatch_sp(r12)
/* Check stack marker hasn't been trashed */
lis r2, STACK_END_MAGIC@h
ori r2, r2, STACK_END_MAGIC@l
- ld r12, -8(r1)
+ ld r12, -8(r11)
1: tdne r12, r2
EMIT_BUG_ENTRY 1b, __FILE__, __LINE__ - 1, 0
/* Restore LR & toc from livepatch stack */
- ld r12, -16(r1)
+ ld r12, -16(r11)
mtlr r12
- ld r2, -24(r1)
+ ld r2, -24(r11)
/* Pop livepatch stack frame */
- CURRENT_THREAD_INFO(r12, r0)
- subi r1, r1, 24
- std r1, TI_livepatch_sp(r12)
-
- /* Restore real stack pointer */
- mr r1, r0
+ CURRENT_THREAD_INFO(r12, r1)
+ subi r11, r11, 24
+ std r11, TI_livepatch_sp(r12)
/* Return to original caller of live patched function */
blr
diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
index 5e8418c..f208f56 100644
--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c
@@ -1684,11 +1684,13 @@ int analyse_instr(struct instruction_op *op, const struct pt_regs *regs,
* Logical instructions
*/
case 26: /* cntlzw */
- op->val = __builtin_clz((unsigned int) regs->gpr[rd]);
+ val = (unsigned int) regs->gpr[rd];
+ op->val = ( val ? __builtin_clz(val) : 32 );
goto logical_done;
#ifdef __powerpc64__
case 58: /* cntlzd */
- op->val = __builtin_clzl(regs->gpr[rd]);
+ val = regs->gpr[rd];
+ op->val = ( val ? __builtin_clzl(val) : 64 );
goto logical_done;
#endif
case 28: /* and */
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index b95c584..a51df9e 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -1438,7 +1438,6 @@ int numa_update_cpu_topology(bool cpus_locked)
int arch_update_cpu_topology(void)
{
- lockdep_assert_cpus_held();
return numa_update_cpu_topology(true);
}
diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
index 9ccac86..8812624 100644
--- a/arch/powerpc/perf/imc-pmu.c
+++ b/arch/powerpc/perf/imc-pmu.c
@@ -399,6 +399,20 @@ static void nest_imc_counters_release(struct perf_event *event)
/* Take the mutex lock for this node and then decrement the reference count */
mutex_lock(&ref->lock);
+ if (ref->refc == 0) {
+ /*
+ * The scenario where this is true is, when perf session is
+ * started, followed by offlining of all cpus in a given node.
+ *
+ * In the cpuhotplug offline path, ppc_nest_imc_cpu_offline()
+ * function set the ref->count to zero, if the cpu which is
+ * about to offline is the last cpu in a given node and make
+ * an OPAL call to disable the engine in that node.
+ *
+ */
+ mutex_unlock(&ref->lock);
+ return;
+ }
ref->refc--;
if (ref->refc == 0) {
rc = opal_imc_counters_stop(OPAL_IMC_COUNTERS_NEST,
@@ -523,8 +537,8 @@ static int core_imc_mem_init(int cpu, int size)
/* We need only vbase for core counters */
mem_info->vbase = page_address(alloc_pages_node(phys_id,
- GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE,
- get_order(size)));
+ GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE |
+ __GFP_NOWARN, get_order(size)));
if (!mem_info->vbase)
return -ENOMEM;
@@ -646,6 +660,20 @@ static void core_imc_counters_release(struct perf_event *event)
return;
mutex_lock(&ref->lock);
+ if (ref->refc == 0) {
+ /*
+ * The scenario where this is true is, when perf session is
+ * started, followed by offlining of all cpus in a given core.
+ *
+ * In the cpuhotplug offline path, ppc_core_imc_cpu_offline()
+ * function set the ref->count to zero, if the cpu which is
+ * about to offline is the last cpu in a given core and make
+ * an OPAL call to disable the engine in that core.
+ *
+ */
+ mutex_unlock(&ref->lock);
+ return;
+ }
ref->refc--;
if (ref->refc == 0) {
rc = opal_imc_counters_stop(OPAL_IMC_COUNTERS_CORE,
@@ -763,8 +791,8 @@ static int thread_imc_mem_alloc(int cpu_id, int size)
* free the memory in cpu offline path.
*/
local_mem = page_address(alloc_pages_node(phys_id,
- GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE,
- get_order(size)));
+ GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE |
+ __GFP_NOWARN, get_order(size)));
if (!local_mem)
return -ENOMEM;
@@ -1148,7 +1176,8 @@ static void imc_common_cpuhp_mem_free(struct imc_pmu *pmu_ptr)
}
/* Only free the attr_groups which are dynamically allocated */
- kfree(pmu_ptr->attr_groups[IMC_EVENT_ATTR]->attrs);
+ if (pmu_ptr->attr_groups[IMC_EVENT_ATTR])
+ kfree(pmu_ptr->attr_groups[IMC_EVENT_ATTR]->attrs);
kfree(pmu_ptr->attr_groups[IMC_EVENT_ATTR]);
kfree(pmu_ptr);
return;