Merge remote branch 'intel/drm-intel-next' of ../drm-next into drm-core-next

* 'intel/drm-intel-next' of ../drm-next: (755 commits)
  drm/i915: Only wait on a pending flip if we intend to write to the buffer
  drm/i915/dp: Sanity check eDP existence
  drm/i915: Rebind the buffer if its alignment constraints changes with tiling
  drm/i915: Disable GPU semaphores by default
  drm/i915: Do not overflow the MMADDR write FIFO
  Revert "drm/i915: fix corruptions on i8xx due to relaxed fencing"
  drm/i915: Don't save/restore hardware status page address register
  drm/i915: don't store the reg value for HWS_PGA
  drm/i915: fix memory corruption with GM965 and >4GB RAM
  Linux 2.6.38-rc7
  Revert "TPM: Long default timeout fix"
  drm/i915: Re-enable GPU semaphores for SandyBridge mobile
  drm/i915: Replace vblank PM QoS with "Interrupt-Based AGPBUSY#"
  Revert "drm/i915: Use PM QoS to prevent C-State starvation of gen3 GPU"
  drm/i915: Allow relocation deltas outside of target bo
  drm/i915: Silence an innocuous compiler warning for an unused variable
  fs/block_dev.c: fix new kernel-doc warning
  ACPI: Fix build for CONFIG_NET unset
  mm: <asm-generic/pgtable.h> must include <linux/mm_types.h>
  x86: Use u32 instead of long to set reset vector back to 0
  ...

Conflicts:
	drivers/gpu/drm/i915/i915_gem.c

1 files changed, 37 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c
index 5d3ea9f60dd7..ca5d5898d320 100644
--- a/arch/powerpc/platforms/pseries/lpar.c
+++ b/arch/powerpc/platforms/pseries/lpar.c
@@ -713,6 +713,13 @@ EXPORT_SYMBOL(arch_free_page);
 /* NB: reg/unreg are called while guarded with the tracepoints_mutex */
 extern long hcall_tracepoint_refcount;
 
+/* 
+ * Since the tracing code might execute hcalls we need to guard against
+ * recursion. One example of this are spinlocks calling H_YIELD on
+ * shared processor partitions.
+ */
+static DEFINE_PER_CPU(unsigned int, hcall_trace_depth);
+
 void hcall_tracepoint_regfunc(void)
 {
 	hcall_tracepoint_refcount++;
@@ -725,12 +732,42 @@ void hcall_tracepoint_unregfunc(void)
 
 void __trace_hcall_entry(unsigned long opcode, unsigned long *args)
 {
+	unsigned long flags;
+	unsigned int *depth;
+
+	local_irq_save(flags);
+
+	depth = &__get_cpu_var(hcall_trace_depth);
+
+	if (*depth)
+		goto out;
+
+	(*depth)++;
 	trace_hcall_entry(opcode, args);
+	(*depth)--;
+
+out:
+	local_irq_restore(flags);
 }
 
 void __trace_hcall_exit(long opcode, unsigned long retval,
 			unsigned long *retbuf)
 {
+	unsigned long flags;
+	unsigned int *depth;
+
+	local_irq_save(flags);
+
+	depth = &__get_cpu_var(hcall_trace_depth);
+
+	if (*depth)
+		goto out;
+
+	(*depth)++;
 	trace_hcall_exit(opcode, retval, retbuf);
+	(*depth)--;
+
+out:
+	local_irq_restore(flags);
 }
 #endif