Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

Pull powerpc fixes from Benjamin Herrenschmidt:
 "This is mostly bug fixes (some of them regressions, some of them I
  deemed worth merging now) along with some patches from Li Zhong
  hooking up the new context tracking stuff (for the new full NO_HZ)"

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (25 commits)
  powerpc: Set show_unhandled_signals to 1 by default
  powerpc/perf: Fix setting of "to" addresses for BHRB
  powerpc/pmu: Fix order of interpreting BHRB target entries
  powerpc/perf: Move BHRB code into CONFIG_PPC64 region
  powerpc: select HAVE_CONTEXT_TRACKING for pSeries
  powerpc: Use the new schedule_user API on userspace preemption
  powerpc: Exit user context on notify resume
  powerpc: Exception hooks for context tracking subsystem
  powerpc: Syscall hooks for context tracking subsystem
  powerpc/booke64: Fix kernel hangs at kernel_dbg_exc
  powerpc: Fix irq_set_affinity() return values
  powerpc: Provide __bswapdi2
  powerpc/powernv: Fix starting of secondary CPUs on OPALv2 and v3
  powerpc/powernv: Detect OPAL v3 API version
  powerpc: Fix MAX_STACK_TRACE_ENTRIES too low warning again
  powerpc: Make CONFIG_RTAS_PROC depend on CONFIG_PROC_FS
  powerpc: Bring all threads online prior to migration/hibernation
  powerpc/rtas_flash: Fix validate_flash buffer overflow issue
  powerpc/kexec: Fix kexec when using VMX optimised memcpy
  powerpc: Fix build errors STRICT_MM_TYPECHECKS
  ...

1 files changed, 159 insertions, 121 deletions

diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c
index c627843c5b2e..426180b84978 100644
--- a/arch/powerpc/perf/core-book3s.c
+++ b/arch/powerpc/perf/core-book3s.c
@@ -13,11 +13,13 @@
 #include <linux/perf_event.h>
 #include <linux/percpu.h>
 #include <linux/hardirq.h>
+#include <linux/uaccess.h>
 #include <asm/reg.h>
 #include <asm/pmc.h>
 #include <asm/machdep.h>
 #include <asm/firmware.h>
 #include <asm/ptrace.h>
+#include <asm/code-patching.h>
 
 #define BHRB_MAX_ENTRIES        32
 #define BHRB_TARGET             0x0000000000000002
@@ -100,6 +102,10 @@ static inline int siar_valid(struct pt_regs *regs)
         return 1;
 }
 
+static inline void power_pmu_bhrb_enable(struct perf_event *event) {}
+static inline void power_pmu_bhrb_disable(struct perf_event *event) {}
+void power_pmu_flush_branch_stack(void) {}
+static inline void power_pmu_bhrb_read(struct cpu_hw_events *cpuhw) {}
 #endif /* CONFIG_PPC32 */
 
 static bool regs_use_siar(struct pt_regs *regs)
@@ -308,6 +314,159 @@ static inline int siar_valid(struct pt_regs *regs)
         return 1;
 }
 
+
+/* Reset all possible BHRB entries */
+static void power_pmu_bhrb_reset(void)
+{
+        asm volatile(PPC_CLRBHRB);
+}
+
+static void power_pmu_bhrb_enable(struct perf_event *event)
+{
+        struct cpu_hw_events *cpuhw = &__get_cpu_var(cpu_hw_events);
+
+        if (!ppmu->bhrb_nr)
+                return;
+
+        /* Clear BHRB if we changed task context to avoid data leaks */
+        if (event->ctx->task && cpuhw->bhrb_context != event->ctx) {
+                power_pmu_bhrb_reset();
+                cpuhw->bhrb_context = event->ctx;
+        }
+        cpuhw->bhrb_users++;
+}
+
+static void power_pmu_bhrb_disable(struct perf_event *event)
+{
+        struct cpu_hw_events *cpuhw = &__get_cpu_var(cpu_hw_events);
+
+        if (!ppmu->bhrb_nr)
+                return;
+
+        cpuhw->bhrb_users--;
+        WARN_ON_ONCE(cpuhw->bhrb_users < 0);
+
+        if (!cpuhw->disabled && !cpuhw->bhrb_users) {
+                /* BHRB cannot be turned off when other
+                 * events are active on the PMU.
+                 */
+
+                /* avoid stale pointer */
+                cpuhw->bhrb_context = NULL;
+        }
+}
+
+/* Called from ctxsw to prevent one process's branch entries to
+ * mingle with the other process's entries during context switch.
+ */
+void power_pmu_flush_branch_stack(void)
+{
+        if (ppmu->bhrb_nr)
+                power_pmu_bhrb_reset();
+}
+/* Calculate the to address for a branch */
+static __u64 power_pmu_bhrb_to(u64 addr)
+{
+        unsigned int instr;
+        int ret;
+        __u64 target;
+
+        if (is_kernel_addr(addr))
+                return branch_target((unsigned int *)addr);
+
+        /* Userspace: need copy instruction here then translate it */
+        pagefault_disable();
+        ret = __get_user_inatomic(instr, (unsigned int __user *)addr);
+        if (ret) {
+                pagefault_enable();
+                return 0;
+        }
+        pagefault_enable();
+
+        target = branch_target(&instr);
+        if ((!target) || (instr & BRANCH_ABSOLUTE))
+                return target;
+
+        /* Translate relative branch target from kernel to user address */
+        return target - (unsigned long)&instr + addr;
+}
+
+/* Processing BHRB entries */
+void power_pmu_bhrb_read(struct cpu_hw_events *cpuhw)
+{
+        u64 val;
+        u64 addr;
+        int r_index, u_index, pred;
+
+        r_index = 0;
+        u_index = 0;
+        while (r_index < ppmu->bhrb_nr) {
+                /* Assembly read function */
+                val = read_bhrb(r_index++);
+                if (!val)
+                        /* Terminal marker: End of valid BHRB entries */
+                        break;
+                else {
+                        addr = val & BHRB_EA;
+                        pred = val & BHRB_PREDICTION;
+
+                        if (!addr)
+                                /* invalid entry */
+                                continue;
+
+                        /* Branches are read most recent first (ie. mfbhrb 0 is
+                         * the most recent branch).
+                         * There are two types of valid entries:
+                         * 1) a target entry which is the to address of a
+                         *    computed goto like a blr,bctr,btar.  The next
+                         *    entry read from the bhrb will be branch
+                         *    corresponding to this target (ie. the actual
+                         *    blr/bctr/btar instruction).
+                         * 2) a from address which is an actual branch.  If a
+                         *    target entry proceeds this, then this is the
+                         *    matching branch for that target.  If this is not
+                         *    following a target entry, then this is a branch
+                         *    where the target is given as an immediate field
+                         *    in the instruction (ie. an i or b form branch).
+                         *    In this case we need to read the instruction from
+                         *    memory to determine the target/to address.
+                         */
+
+                        if (val & BHRB_TARGET) {
+                                /* Target branches use two entries
+                                 * (ie. computed gotos/XL form)
+                                 */
+                                cpuhw->bhrb_entries[u_index].to = addr;
+                                cpuhw->bhrb_entries[u_index].mispred = pred;
+                                cpuhw->bhrb_entries[u_index].predicted = ~pred;
+
+                                /* Get from address in next entry */
+                                val = read_bhrb(r_index++);
+                                addr = val & BHRB_EA;
+                                if (val & BHRB_TARGET) {
+                                        /* Shouldn't have two targets in a
+                                           row.. Reset index and try again */
+                                        r_index--;
+                                        addr = 0;
+                                }
+                                cpuhw->bhrb_entries[u_index].from = addr;
+                        } else {
+                                /* Branches to immediate field 
+                                   (ie I or B form) */
+                                cpuhw->bhrb_entries[u_index].from = addr;
+                                cpuhw->bhrb_entries[u_index].to =
+                                        power_pmu_bhrb_to(addr);
+                                cpuhw->bhrb_entries[u_index].mispred = pred;
+                                cpuhw->bhrb_entries[u_index].predicted = ~pred;
+                        }
+                        u_index++;
+
+                }
+        }
+        cpuhw->bhrb_stack.nr = u_index;
+        return;
+}
+
 #endif /* CONFIG_PPC64 */
 
 static void perf_event_interrupt(struct pt_regs *regs);
@@ -904,47 +1063,6 @@ static int collect_events(struct perf_event *group, int max_count,
         return n;
 }
 
-/* Reset all possible BHRB entries */
-static void power_pmu_bhrb_reset(void)
-{
-        asm volatile(PPC_CLRBHRB);
-}
-
-void power_pmu_bhrb_enable(struct perf_event *event)
-{
-        struct cpu_hw_events *cpuhw = &__get_cpu_var(cpu_hw_events);
-
-        if (!ppmu->bhrb_nr)
-                return;
-
-        /* Clear BHRB if we changed task context to avoid data leaks */
-        if (event->ctx->task && cpuhw->bhrb_context != event->ctx) {
-                power_pmu_bhrb_reset();
-                cpuhw->bhrb_context = event->ctx;
-        }
-        cpuhw->bhrb_users++;
-}
-
-void power_pmu_bhrb_disable(struct perf_event *event)
-{
-        struct cpu_hw_events *cpuhw = &__get_cpu_var(cpu_hw_events);
-
-        if (!ppmu->bhrb_nr)
-                return;
-
-        cpuhw->bhrb_users--;
-        WARN_ON_ONCE(cpuhw->bhrb_users < 0);
-
-        if (!cpuhw->disabled && !cpuhw->bhrb_users) {
-                /* BHRB cannot be turned off when other
-                 * events are active on the PMU.
-                 */
-
-                /* avoid stale pointer */
-                cpuhw->bhrb_context = NULL;
-        }
-}
-
 /*
  * Add a event to the PMU.
  * If all events are not already frozen, then we disable and
@@ -1180,15 +1298,6 @@ int power_pmu_commit_txn(struct pmu *pmu)
         return 0;
 }
 
-/* Called from ctxsw to prevent one process's branch entries to
- * mingle with the other process's entries during context switch.
- */
-void power_pmu_flush_branch_stack(void)
-{
-        if (ppmu->bhrb_nr)
-                power_pmu_bhrb_reset();
-}
-
 /*
  * Return 1 if we might be able to put event on a limited PMC,
  * or 0 if not.
@@ -1458,77 +1567,6 @@ struct pmu power_pmu = {
         .flush_branch_stack = power_pmu_flush_branch_stack,
 };
 
-/* Processing BHRB entries */
-void power_pmu_bhrb_read(struct cpu_hw_events *cpuhw)
-{
-        u64 val;
-        u64 addr;
-        int r_index, u_index, target, pred;
-
-        r_index = 0;
-        u_index = 0;
-        while (r_index < ppmu->bhrb_nr) {
-                /* Assembly read function */
-                val = read_bhrb(r_index);
-
-                /* Terminal marker: End of valid BHRB entries */
-                if (val == 0) {
-                        break;
-                } else {
-                        /* BHRB field break up */
-                        addr = val & BHRB_EA;
-                        pred = val & BHRB_PREDICTION;
-                        target = val & BHRB_TARGET;
-
-                        /* Probable Missed entry: Not applicable for POWER8 */
-                        if ((addr == 0) && (target == 0) && (pred == 1)) {
-                                r_index++;
-                                continue;
-                        }
-
-                        /* Real Missed entry: Power8 based missed entry */
-                        if ((addr == 0) && (target == 1) && (pred == 1)) {
-                                r_index++;
-                                continue;
-                        }
-
-                        /* Reserved condition: Not a valid entry  */
-                        if ((addr == 0) && (target == 1) && (pred == 0)) {
-                                r_index++;
-                                continue;
-                        }
-
-                        /* Is a target address */
-                        if (val & BHRB_TARGET) {
-                                /* First address cannot be a target address */
-                                if (r_index == 0) {
-                                        r_index++;
-                                        continue;
-                                }
-
-                                /* Update target address for the previous entry */
-                                cpuhw->bhrb_entries[u_index - 1].to = addr;
-                                cpuhw->bhrb_entries[u_index - 1].mispred = pred;
-                                cpuhw->bhrb_entries[u_index - 1].predicted = ~pred;
-
-                                /* Dont increment u_index */
-                                r_index++;
-                        } else {
-                                /* Update address, flags for current entry */
-                                cpuhw->bhrb_entries[u_index].from = addr;
-                                cpuhw->bhrb_entries[u_index].mispred = pred;
-                                cpuhw->bhrb_entries[u_index].predicted = ~pred;
-
-                                /* Successfully popullated one entry */
-                                u_index++;
-                                r_index++;
-                        }
-                }
-        }
-        cpuhw->bhrb_stack.nr = u_index;
-        return;
-}
-
 /*
  * A counter has overflowed; update its count and record
  * things if requested.  Note that interrupts are hard-disabled