Merge tag 'for-linus' of git://github.com/openrisc/linux

Pull OpenRISC updates from Stafford Horne:
 "A few cleanups all over the place, things of note:

   - Enable the clone3 syscall

   - Remove CONFIG_CROSS_COMPILE from Krzysztof Kozlowski

   - Update to use mmgrab from Julia Lawall"

* tag 'for-linus' of git://github.com/openrisc/linux:
  openrisc: Remove obsolete show_trace_task function
  openrisc: Cleanup copy_thread_tls docs and comments
  openrisc: Enable the clone3 syscall
  openrisc: Convert copy_thread to copy_thread_tls
  openrisc: use mmgrab
  openrisc: configs: Cleanup CONFIG_CROSS_COMPILE

Author: torvalds

Documentation/openrisc/openrisc_port.rst

@@ -37,8 +37,8 @@ or Stafford's toolchain build and release scripts.
 
 Build the Linux kernel as usual::
 
-	make ARCH=openrisc defconfig
-	make ARCH=openrisc
+	make ARCH=openrisc CROSS_COMPILE="or1k-linux-" defconfig
+	make ARCH=openrisc CROSS_COMPILE="or1k-linux-"
 
 3) Running on FPGA (optional)
 

arch/openrisc/Kconfig

@@ -16,6 +16,7 @@ config OPENRISC
 	select HANDLE_DOMAIN_IRQ
 	select GPIOLIB
 	select HAVE_ARCH_TRACEHOOK
+	select HAVE_COPY_THREAD_TLS
 	select SPARSE_IRQ
 	select GENERIC_IRQ_CHIP
 	select GENERIC_IRQ_PROBE

arch/openrisc/configs/or1ksim_defconfig

@@ -1,4 +1,3 @@
-CONFIG_CROSS_COMPILE="or1k-linux-"
 CONFIG_NO_HZ=y
 CONFIG_LOG_BUF_SHIFT=14
 CONFIG_BLK_DEV_INITRD=y

arch/openrisc/configs/simple_smp_defconfig

@@ -1,4 +1,3 @@
-CONFIG_CROSS_COMPILE="or1k-linux-"
 CONFIG_LOCALVERSION="-simple-smp"
 CONFIG_NO_HZ=y
 CONFIG_LOG_BUF_SHIFT=14

arch/openrisc/include/uapi/asm/unistd.h

@@ -24,6 +24,7 @@
 #define __ARCH_WANT_SET_GET_RLIMIT
 #define __ARCH_WANT_SYS_FORK
 #define __ARCH_WANT_SYS_CLONE
+#define __ARCH_WANT_SYS_CLONE3
 #define __ARCH_WANT_TIME32_SYSCALLS
 
 #include <asm-generic/unistd.h>

arch/openrisc/kernel/process.c

@@ -117,12 +117,12 @@ void release_thread(struct task_struct *dead_task)
 extern asmlinkage void ret_from_fork(void);
 
 /*
- * copy_thread
+ * copy_thread_tls
  * @clone_flags: flags
  * @usp: user stack pointer or fn for kernel thread
  * @arg: arg to fn for kernel thread; always NULL for userspace thread
  * @p: the newly created task
- * @regs: CPU context to copy for userspace thread; always NULL for kthread
+ * @tls: the Thread Local Storage pointer for the new process
  *
  * At the top of a newly initialized kernel stack are two stacked pt_reg
  * structures.  The first (topmost) is the userspace context of the thread.
@@ -148,8 +148,8 @@ extern asmlinkage void ret_from_fork(void);
  */
 
 int
-copy_thread(unsigned long clone_flags, unsigned long usp,
-	    unsigned long arg, struct task_struct *p)
+copy_thread_tls(unsigned long clone_flags, unsigned long usp,
+		unsigned long arg, struct task_struct *p, unsigned long tls)
 {
 	struct pt_regs *userregs;
 	struct pt_regs *kregs;
@@ -179,16 +179,10 @@ copy_thread(unsigned long clone_flags, unsigned long usp,
 			userregs->sp = usp;
 
 		/*
-		 * For CLONE_SETTLS set "tp" (r10) to the TLS pointer passed to sys_clone.
-		 *
-		 * The kernel entry is:
-		 *	int clone (long flags, void *child_stack, int *parent_tid,
-		 *		int *child_tid, struct void *tls)
-		 *
-		 * This makes the source r7 in the kernel registers.
+		 * For CLONE_SETTLS set "tp" (r10) to the TLS pointer.
 		 */
 		if (clone_flags & CLONE_SETTLS)
-			userregs->gpr[10] = userregs->gpr[7];
+			userregs->gpr[10] = tls;
 
 		userregs->gpr[11] = 0;	/* Result from fork() */
 

arch/openrisc/kernel/smp.c

@@ -14,6 +14,7 @@
 #include <linux/smp.h>
 #include <linux/cpu.h>
 #include <linux/sched.h>
+#include <linux/sched/mm.h>
 #include <linux/irq.h>
 #include <asm/cpuinfo.h>
 #include <asm/mmu_context.h>
@@ -113,7 +114,7 @@ asmlinkage __init void secondary_start_kernel(void)
 	 * All kernel threads share the same mm context; grab a
 	 * reference and switch to it.
 	 */
-	atomic_inc(&mm->mm_count);
+	mmgrab(mm);
 	current->active_mm = mm;
 	cpumask_set_cpu(cpu, mm_cpumask(mm));
 

arch/openrisc/kernel/traps.c

@@ -55,13 +55,6 @@ void show_stack(struct task_struct *task, unsigned long *esp)
 	unwind_stack(NULL, esp, print_trace);
 }
 
-void show_trace_task(struct task_struct *tsk)
-{
-	/*
-	 * TODO: SysRq-T trace dump...
-	 */
-}
-
 void show_registers(struct pt_regs *regs)
 {
 	int i;