3 files changed, 54 insertions, 37 deletions

diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c
index dc7d0a95bd36..c02c06b1f755 100644
--- a/arch/arm/kernel/hw_breakpoint.c
+++ b/arch/arm/kernel/hw_breakpoint.c
@@ -1067,6 +1067,22 @@ static int __init arch_hw_breakpoint_init(void)
 		return 0;
 	}
 
+	/*
+	 * Scorpion CPUs (at least those in APQ8060) seem to set DBGPRSR.SPD
+	 * whenever a WFI is issued, even if the core is not powered down, in
+	 * violation of the architecture.  When DBGPRSR.SPD is set, accesses to
+	 * breakpoint and watchpoint registers are treated as undefined, so
+	 * this results in boot time and runtime failures when these are
+	 * accessed and we unexpectedly take a trap.
+	 *
+	 * It's not clear if/how this can be worked around, so we blacklist
+	 * Scorpion CPUs to avoid these issues.
+	*/
+	if (read_cpuid_part() == ARM_CPU_PART_SCORPION) {
+		pr_info("Scorpion CPU detected. Hardware breakpoints and watchpoints disabled\n");
+		return 0;
+	}
+
 	has_ossr = core_has_os_save_restore();
 
 	/* Determine how many BRPs/WRPs are available. */
diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index 4d9375814b53..d54c53b7ab63 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -600,7 +600,7 @@ static int gpr_set(struct task_struct *target,
 		   const void *kbuf, const void __user *ubuf)
 {
 	int ret;
-	struct pt_regs newregs;
+	struct pt_regs newregs = *task_pt_regs(target);
 
 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 				 &newregs,
diff --git a/arch/arm/kernel/sys_oabi-compat.c b/arch/arm/kernel/sys_oabi-compat.c
index b83f3b7737fb..087acb569b63 100644
--- a/arch/arm/kernel/sys_oabi-compat.c
+++ b/arch/arm/kernel/sys_oabi-compat.c
@@ -193,15 +193,44 @@ struct oabi_flock64 {
 	pid_t	l_pid;
 } __attribute__ ((packed,aligned(4)));
 
-asmlinkage long sys_oabi_fcntl64(unsigned int fd, unsigned int cmd,
+static long do_locks(unsigned int fd, unsigned int cmd,
 				 unsigned long arg)
 {
-	struct oabi_flock64 user;
 	struct flock64 kernel;
-	mm_segment_t fs = USER_DS; /* initialized to kill a warning */
-	unsigned long local_arg = arg;
-	int ret;
+	struct oabi_flock64 user;
+	mm_segment_t fs;
+	long ret;
+
+	if (copy_from_user(&user, (struct oabi_flock64 __user *)arg,
+			   sizeof(user)))
+		return -EFAULT;
+	kernel.l_type	= user.l_type;
+	kernel.l_whence	= user.l_whence;
+	kernel.l_start	= user.l_start;
+	kernel.l_len	= user.l_len;
+	kernel.l_pid	= user.l_pid;
+
+	fs = get_fs();
+	set_fs(KERNEL_DS);
+	ret = sys_fcntl64(fd, cmd, (unsigned long)&kernel);
+	set_fs(fs);
+
+	if (!ret && (cmd == F_GETLK64 || cmd == F_OFD_GETLK)) {
+		user.l_type	= kernel.l_type;
+		user.l_whence	= kernel.l_whence;
+		user.l_start	= kernel.l_start;
+		user.l_len	= kernel.l_len;
+		user.l_pid	= kernel.l_pid;
+		if (copy_to_user((struct oabi_flock64 __user *)arg,
+				 &user, sizeof(user)))
+			ret = -EFAULT;
+	}
+	return ret;
+}
 
+asmlinkage long sys_oabi_fcntl64(unsigned int fd, unsigned int cmd,
+				 unsigned long arg)
+{
 	switch (cmd) {
 	case F_OFD_GETLK:
 	case F_OFD_SETLK:
@@ -209,39 +238,11 @@ asmlinkage long sys_oabi_fcntl64(unsigned int fd, unsigned int cmd,
 	case F_GETLK64:
 	case F_SETLK64:
 	case F_SETLKW64:
-		if (copy_from_user(&user, (struct oabi_flock64 __user *)arg,
-				   sizeof(user)))
-			return -EFAULT;
-		kernel.l_type	= user.l_type;
-		kernel.l_whence	= user.l_whence;
-		kernel.l_start	= user.l_start;
-		kernel.l_len	= user.l_len;
-		kernel.l_pid	= user.l_pid;
-		local_arg = (unsigned long)&kernel;
-		fs = get_fs();
-		set_fs(KERNEL_DS);
-	}
-
-	ret = sys_fcntl64(fd, cmd, local_arg);
+		return do_locks(fd, cmd, arg);
 
-	switch (cmd) {
-	case F_GETLK64:
-		if (!ret) {
-			user.l_type	= kernel.l_type;
-			user.l_whence	= kernel.l_whence;
-			user.l_start	= kernel.l_start;
-			user.l_len	= kernel.l_len;
-			user.l_pid	= kernel.l_pid;
-			if (copy_to_user((struct oabi_flock64 __user *)arg,
-					 &user, sizeof(user)))
-				ret = -EFAULT;
-		}
-	case F_SETLK64:
-	case F_SETLKW64:
-		set_fs(fs);
+	default:
+		return sys_fcntl64(fd, cmd, arg);
 	}
-
-	return ret;
 }
 
 struct oabi_epoll_event {