4 files changed, 33 insertions, 13 deletions

diff --git a/arch/powerpc/kernel/dma-iommu.c b/arch/powerpc/kernel/dma-iommu.c
index 2d7bb8ced136..e4897523de41 100644
--- a/arch/powerpc/kernel/dma-iommu.c
+++ b/arch/powerpc/kernel/dma-iommu.c
@@ -83,11 +83,10 @@ static int dma_iommu_dma_supported(struct device *dev, u64 mask)
 		return 0;
 	}
 
-	if ((tbl->it_offset + tbl->it_size) > (mask >> IOMMU_PAGE_SHIFT)) {
-		dev_info(dev, "Warning: IOMMU window too big for device mask\n");
-		dev_info(dev, "mask: 0x%08llx, table end: 0x%08lx\n",
-				mask, (tbl->it_offset + tbl->it_size) <<
-				IOMMU_PAGE_SHIFT);
+	if (tbl->it_offset > (mask >> IOMMU_PAGE_SHIFT)) {
+		dev_info(dev, "Warning: IOMMU offset too big for device mask\n");
+		dev_info(dev, "mask: 0x%08llx, table offset: 0x%08lx\n",
+				mask, tbl->it_offset << IOMMU_PAGE_SHIFT);
 		return 0;
 	} else
 		return 1;
diff --git a/arch/powerpc/kernel/hw_breakpoint.c b/arch/powerpc/kernel/hw_breakpoint.c
index f3a82dde61db..956a4c496de9 100644
--- a/arch/powerpc/kernel/hw_breakpoint.c
+++ b/arch/powerpc/kernel/hw_breakpoint.c
@@ -253,7 +253,7 @@ int __kprobes hw_breakpoint_handler(struct die_args *args)
 
 	/* Do not emulate user-space instructions, instead single-step them */
 	if (user_mode(regs)) {
-		bp->ctx->task->thread.last_hit_ubp = bp;
+		current->thread.last_hit_ubp = bp;
 		regs->msr |= MSR_SE;
 		goto out;
 	}
diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
index 782bd0a3c2f0..c470a40b29f5 100644
--- a/arch/powerpc/kernel/kgdb.c
+++ b/arch/powerpc/kernel/kgdb.c
@@ -25,6 +25,7 @@
 #include <asm/processor.h>
 #include <asm/machdep.h>
 #include <asm/debug.h>
+#include <linux/slab.h>
 
 /*
  * This table contains the mapping between PowerPC hardware trap types, and
@@ -101,6 +102,21 @@ static int computeSignal(unsigned int tt)
 	return SIGHUP;		/* default for things we don't know about */
 }
 
+/**
+ *
+ *	kgdb_skipexception - Bail out of KGDB when we've been triggered.
+ *	@exception: Exception vector number
+ *	@regs: Current &struct pt_regs.
+ *
+ *	On some architectures we need to skip a breakpoint exception when
+ *	it occurs after a breakpoint has been removed.
+ *
+ */
+int kgdb_skipexception(int exception, struct pt_regs *regs)
+{
+	return kgdb_isremovedbreak(regs->nip);
+}
+
 static int kgdb_call_nmi_hook(struct pt_regs *regs)
 {
 	kgdb_nmicallback(raw_smp_processor_id(), regs);
@@ -138,6 +154,8 @@ static int kgdb_handle_breakpoint(struct pt_regs *regs)
 static int kgdb_singlestep(struct pt_regs *regs)
 {
 	struct thread_info *thread_info, *exception_thread_info;
+	struct thread_info *backup_current_thread_info = \
+		(struct thread_info *)kmalloc(sizeof(struct thread_info), GFP_KERNEL);
 
 	if (user_mode(regs))
 		return 0;
@@ -155,13 +173,17 @@ static int kgdb_singlestep(struct pt_regs *regs)
 	thread_info = (struct thread_info *)(regs->gpr[1] & ~(THREAD_SIZE-1));
 	exception_thread_info = current_thread_info();
 
-	if (thread_info != exception_thread_info)
+	if (thread_info != exception_thread_info) {
+		/* Save the original current_thread_info. */
+		memcpy(backup_current_thread_info, exception_thread_info, sizeof *thread_info);
 		memcpy(exception_thread_info, thread_info, sizeof *thread_info);
+	}
 
 	kgdb_handle_exception(0, SIGTRAP, 0, regs);
 
 	if (thread_info != exception_thread_info)
-		memcpy(thread_info, exception_thread_info, sizeof *thread_info);
+		/* Restore current_thread_info lastly. */
+		memcpy(exception_thread_info, backup_current_thread_info, sizeof *thread_info);
 
 	return 1;
 }
@@ -410,7 +432,6 @@ int kgdb_arch_handle_exception(int vector, int signo, int err_code,
 #else
 			linux_regs->msr |= MSR_SE;
 #endif
-			kgdb_single_step = 1;
 			atomic_set(&kgdb_cpu_doing_single_step,
 				   raw_smp_processor_id());
 		}
diff --git a/arch/powerpc/kernel/syscalls.c b/arch/powerpc/kernel/syscalls.c
index f2496f2faecc..4e3cc47f26b9 100644
--- a/arch/powerpc/kernel/syscalls.c
+++ b/arch/powerpc/kernel/syscalls.c
@@ -107,11 +107,11 @@ long ppc64_personality(unsigned long personality)
 	long ret;
 
 	if (personality(current->personality) == PER_LINUX32
-	    && personality == PER_LINUX)
-		personality = PER_LINUX32;
+	    && personality(personality) == PER_LINUX)
+		personality = (personality & ~PER_MASK) | PER_LINUX32;
 	ret = sys_personality(personality);
-	if (ret == PER_LINUX32)
-		ret = PER_LINUX;
+	if (personality(ret) == PER_LINUX32)
+		ret = (ret & ~PER_MASK) | PER_LINUX;
 	return ret;
 }
 #endif