Merge tag 'xtensa-20191201' of git://github.com/jcmvbkbc/linux-xtensa

Pull Xtensa updates from Max Filippov:

 - add support for execute in place (XIP) kernels

 - improvements in inline assembly: use named arguments and "m"
   constraints where possible

 - improve stack dumping

 - clean up system_call code and syscall tracing

 - various small fixes and cleanups

* tag 'xtensa-20191201' of git://github.com/jcmvbkbc/linux-xtensa: (30 commits)
  xtensa: clean up system_call/xtensa_rt_sigreturn interaction
  xtensa: fix system_call interaction with ptrace
  xtensa: rearrange syscall tracing
  xtensa: fix syscall_set_return_value
  xtensa: drop unneeded headers from coprocessor.S
  xtensa: entry: Remove unneeded need_resched() loop
  xtensa: use MEMBLOCK_ALLOC_ANYWHERE for KASAN shadow map
  xtensa: fix TLB sanity checker
  xtensa: get rid of __ARCH_USE_5LEVEL_HACK
  xtensa: mm: fix PMD folding implementation
  xtensa: make stack dump size configurable
  xtensa: improve stack dumping
  xtensa: use "m" constraint instead of "r" in futex.h assembly
  xtensa: use "m" constraint instead of "a" in cmpxchg.h assembly
  xtensa: use named assembly arguments in cmpxchg.h
  xtensa: use "m" constraint instead of "a" in atomic.h assembly
  xtensa: use named assembly arguments in atomic.h
  xtensa: use "m" constraint instead of "a" in bitops.h assembly
  xtensa: use named assembly arguments in bitops.h
  xtensa: use macros to generate *_bit and test_and_*_bit functions
  ...

9 files changed, 106 insertions, 55 deletions

diff --git a/arch/xtensa/kernel/coprocessor.S b/arch/xtensa/kernel/coprocessor.S
index 80828b95a51f..bb8e499b9900 100644
--- a/arch/xtensa/kernel/coprocessor.S
+++ b/arch/xtensa/kernel/coprocessor.S
@@ -15,17 +15,9 @@
 #include <linux/linkage.h>
 #include <asm/asm-offsets.h>
 #include <asm/asmmacro.h>
-#include <asm/processor.h>
 #include <asm/coprocessor.h>
-#include <asm/thread_info.h>
-#include <asm/asm-uaccess.h>
-#include <asm/unistd.h>
-#include <asm/ptrace.h>
 #include <asm/current.h>
-#include <asm/pgtable.h>
-#include <asm/page.h>
-#include <asm/signal.h>
-#include <asm/tlbflush.h>
+#include <asm/regs.h>
 
 #if XTENSA_HAVE_COPROCESSORS
 
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index 9e3676879168..be897803834a 100644
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -529,7 +529,7 @@ common_exception_return:
 	l32i	a4, a2, TI_PRE_COUNT
 	bnez	a4, 4f
 	call4	preempt_schedule_irq
-	j	1b
+	j	4f
 #endif
 
 #if XTENSA_FAKE_NMI
@@ -1876,8 +1876,7 @@ ENDPROC(fast_store_prohibited)
 
 ENTRY(system_call)
 
-	/* reserve 4 bytes on stack for function parameter */
-	abi_entry(4)
+	abi_entry_default
 
 	/* regs->syscall = regs->areg[2] */
 
@@ -1892,11 +1891,10 @@ ENTRY(system_call)
 
 	mov	a6, a2
 	call4	do_syscall_trace_enter
+	beqz	a6, .Lsyscall_exit
 	l32i	a7, a2, PT_SYSCALL
 
 1:
-	s32i	a7, a1, 4
-
 	/* syscall = sys_call_table[syscall_nr] */
 
 	movi	a4, sys_call_table
@@ -1906,8 +1904,6 @@ ENTRY(system_call)
 
 	addx4	a4, a7, a4
 	l32i	a4, a4, 0
-	movi	a5, sys_ni_syscall;
-	beq	a4, a5, 1f
 
 	/* Load args: arg0 - arg5 are passed via regs. */
 
@@ -1918,25 +1914,19 @@ ENTRY(system_call)
 	l32i	a10, a2, PT_AREG8
 	l32i	a11, a2, PT_AREG9
 
-	/* Pass one additional argument to the syscall: pt_regs (on stack) */
-	s32i	a2, a1, 0
-
 	callx4	a4
 
 1:	/* regs->areg[2] = return_value */
 
 	s32i	a6, a2, PT_AREG2
 	bnez	a3, 1f
-	abi_ret(4)
+.Lsyscall_exit:
+	abi_ret_default
 
 1:
-	l32i	a4, a1, 4
-	l32i	a3, a2, PT_SYSCALL
-	s32i	a4, a2, PT_SYSCALL
 	mov	a6, a2
 	call4	do_syscall_trace_leave
-	s32i	a3, a2, PT_SYSCALL
-	abi_ret(4)
+	abi_ret_default
 
 ENDPROC(system_call)
 
diff --git a/arch/xtensa/kernel/head.S b/arch/xtensa/kernel/head.S
index 4ae998b5a348..e0c1fac0910f 100644
--- a/arch/xtensa/kernel/head.S
+++ b/arch/xtensa/kernel/head.S
@@ -260,6 +260,13 @@ ENTRY(_startup)
 	___invalidate_icache_all a2 a3
 	isync
 
+#ifdef CONFIG_XIP_KERNEL
+	/* Setup bootstrap CPU stack in XIP kernel */
+
+	movi	a1, start_info
+	l32i	a1, a1, 0
+#endif
+
 	movi	a6, 0
 	xsr	a6, excsave1
 
@@ -355,10 +362,10 @@ ENDPROC(cpu_restart)
  * DATA section
  */
 
-        .section ".data.init.refok"
-        .align  4
+	__REFDATA
+	.align  4
 ENTRY(start_info)
-        .long   init_thread_union + KERNEL_STACK_SIZE
+	.long	init_thread_union + KERNEL_STACK_SIZE
 
 /*
  * BSS section
diff --git a/arch/xtensa/kernel/process.c b/arch/xtensa/kernel/process.c
index db278a9e80c7..9e1c49134c07 100644
--- a/arch/xtensa/kernel/process.c
+++ b/arch/xtensa/kernel/process.c
@@ -264,6 +264,8 @@ int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
 			       &regs->areg[XCHAL_NUM_AREGS - len/4], len);
 		}
 
+		childregs->syscall = regs->syscall;
+
 		/* The thread pointer is passed in the '4th argument' (= a5) */
 		if (clone_flags & CLONE_SETTLS)
 			childregs->threadptr = childregs->areg[5];
diff --git a/arch/xtensa/kernel/ptrace.c b/arch/xtensa/kernel/ptrace.c
index b964f0b2d886..145742d70a9f 100644
--- a/arch/xtensa/kernel/ptrace.c
+++ b/arch/xtensa/kernel/ptrace.c
@@ -542,14 +542,28 @@ long arch_ptrace(struct task_struct *child, long request,
 	return ret;
 }
 
-void do_syscall_trace_enter(struct pt_regs *regs)
+void do_syscall_trace_leave(struct pt_regs *regs);
+int do_syscall_trace_enter(struct pt_regs *regs)
 {
+	if (regs->syscall == NO_SYSCALL)
+		regs->areg[2] = -ENOSYS;
+
 	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
-	    tracehook_report_syscall_entry(regs))
+	    tracehook_report_syscall_entry(regs)) {
+		regs->areg[2] = -ENOSYS;
 		regs->syscall = NO_SYSCALL;
+		return 0;
+	}
+
+	if (regs->syscall == NO_SYSCALL) {
+		do_syscall_trace_leave(regs);
+		return 0;
+	}
 
 	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
 		trace_sys_enter(regs, syscall_get_nr(current, regs));
+
+	return 1;
 }
 
 void do_syscall_trace_leave(struct pt_regs *regs)
diff --git a/arch/xtensa/kernel/setup.c b/arch/xtensa/kernel/setup.c
index e0e1e1892b86..0f93b67c7a5a 100644
--- a/arch/xtensa/kernel/setup.c
+++ b/arch/xtensa/kernel/setup.c
@@ -308,6 +308,10 @@ extern char _Level6InterruptVector_text_end;
 extern char _SecondaryResetVector_text_start;
 extern char _SecondaryResetVector_text_end;
 #endif
+#ifdef CONFIG_XIP_KERNEL
+extern char _xip_start[];
+extern char _xip_end[];
+#endif
 
 static inline int __init_memblock mem_reserve(unsigned long start,
 					      unsigned long end)
@@ -339,6 +343,9 @@ void __init setup_arch(char **cmdline_p)
 #endif
 
 	mem_reserve(__pa(_stext), __pa(_end));
+#ifdef CONFIG_XIP_KERNEL
+	mem_reserve(__pa(_xip_start), __pa(_xip_end));
+#endif
 
 #ifdef CONFIG_VECTORS_OFFSET
 	mem_reserve(__pa(&_WindowVectors_text_start),
diff --git a/arch/xtensa/kernel/signal.c b/arch/xtensa/kernel/signal.c
index dae83cddd6ca..76cee341507b 100644
--- a/arch/xtensa/kernel/signal.c
+++ b/arch/xtensa/kernel/signal.c
@@ -236,9 +236,9 @@ restore_sigcontext(struct pt_regs *regs, struct rt_sigframe __user *frame)
  * Do a signal return; undo the signal stack.
  */
 
-asmlinkage long xtensa_rt_sigreturn(long a0, long a1, long a2, long a3,
-				    long a4, long a5, struct pt_regs *regs)
+asmlinkage long xtensa_rt_sigreturn(void)
 {
+	struct pt_regs *regs = current_pt_regs();
 	struct rt_sigframe __user *frame;
 	sigset_t set;
 	int ret;
diff --git a/arch/xtensa/kernel/traps.c b/arch/xtensa/kernel/traps.c
index 4a6c495ce9b6..87bd68dd7687 100644
--- a/arch/xtensa/kernel/traps.c
+++ b/arch/xtensa/kernel/traps.c
@@ -491,32 +491,27 @@ void show_trace(struct task_struct *task, unsigned long *sp)
 
 	pr_info("Call Trace:\n");
 	walk_stackframe(sp, show_trace_cb, NULL);
-#ifndef CONFIG_KALLSYMS
-	pr_cont("\n");
-#endif
 }
 
-static int kstack_depth_to_print = 24;
+#define STACK_DUMP_ENTRY_SIZE 4
+#define STACK_DUMP_LINE_SIZE 32
+static size_t kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH;
 
 void show_stack(struct task_struct *task, unsigned long *sp)
 {
-	int i = 0;
-	unsigned long *stack;
+	size_t len;
 
 	if (!sp)
 		sp = stack_pointer(task);
-	stack = sp;
 
-	pr_info("Stack:\n");
+	len = min((-(size_t)sp) & (THREAD_SIZE - STACK_DUMP_ENTRY_SIZE),
+		  kstack_depth_to_print * STACK_DUMP_ENTRY_SIZE);
 
-	for (i = 0; i < kstack_depth_to_print; i++) {
-		if (kstack_end(sp))
-			break;
-		pr_cont(" %08lx", *sp++);
-		if (i % 8 == 7)
-			pr_cont("\n");
-	}
-	show_trace(task, stack);
+	pr_info("Stack:\n");
+	print_hex_dump(KERN_INFO, " ", DUMP_PREFIX_NONE,
+		       STACK_DUMP_LINE_SIZE, STACK_DUMP_ENTRY_SIZE,
+		       sp, len, false);
+	show_trace(task, sp);
 }
 
 DEFINE_SPINLOCK(die_lock);
diff --git a/arch/xtensa/kernel/vmlinux.lds.S b/arch/xtensa/kernel/vmlinux.lds.S
index 0043d5858f14..409c05cac15e 100644
--- a/arch/xtensa/kernel/vmlinux.lds.S
+++ b/arch/xtensa/kernel/vmlinux.lds.S
@@ -119,7 +119,7 @@ SECTIONS
     SCHED_TEXT
     CPUIDLE_TEXT
     LOCK_TEXT
-
+    *(.fixup)
   }
   _etext = .;
   PROVIDE (etext = .);
@@ -128,12 +128,11 @@ SECTIONS
 
   RO_DATA(4096)
 
-  /*  Relocation table */
-
-  .fixup   : { *(.fixup) }
-
   /* Data section */
 
+#ifdef CONFIG_XIP_KERNEL
+  INIT_TEXT_SECTION(PAGE_SIZE)
+#else
   _sdata = .;
   RW_DATA(XCHAL_ICACHE_LINESIZE, PAGE_SIZE, THREAD_SIZE)
   _edata = .;
@@ -147,6 +146,11 @@ SECTIONS
   .init.data :
   {
     INIT_DATA
+  }
+#endif
+
+  .init.rodata :
+  {
     . = ALIGN(0x4);
     __tagtable_begin = .;
     *(.taglist)
@@ -187,12 +191,16 @@ SECTIONS
     RELOCATE_ENTRY(_DebugInterruptVector_text,
 		   .DebugInterruptVector.text);
 #endif
+#ifdef CONFIG_XIP_KERNEL
+    RELOCATE_ENTRY(_xip_data, .data);
+    RELOCATE_ENTRY(_xip_init_data, .init.data);
+#else
 #if defined(CONFIG_SMP)
     RELOCATE_ENTRY(_SecondaryResetVector_text,
 		   .SecondaryResetVector.text);
 #endif
+#endif
 
-  
     __boot_reloc_table_end = ABSOLUTE(.) ;
 
     INIT_SETUP(XCHAL_ICACHE_LINESIZE)
@@ -278,7 +286,7 @@ SECTIONS
   . = (LOADADDR( .DoubleExceptionVector.text ) + SIZEOF( .DoubleExceptionVector.text ) + 3) & ~ 3;
 
 #endif
-#if defined(CONFIG_SMP)
+#if !defined(CONFIG_XIP_KERNEL) && defined(CONFIG_SMP)
 
   SECTION_VECTOR (_SecondaryResetVector_text,
 		  .SecondaryResetVector.text,
@@ -291,12 +299,48 @@ SECTIONS
 
   . = ALIGN(PAGE_SIZE);
 
+#ifndef CONFIG_XIP_KERNEL
   __init_end = .;
 
   BSS_SECTION(0, 8192, 0)
+#endif
 
   _end = .;
 
+#ifdef CONFIG_XIP_KERNEL
+  . = CONFIG_XIP_DATA_ADDR;
+
+  _xip_start = .;
+
+#undef LOAD_OFFSET
+#define LOAD_OFFSET \
+  (CONFIG_XIP_DATA_ADDR - (LOADADDR(.dummy) + SIZEOF(.dummy) + 3) & ~ 3)
+
+  _xip_data_start = .;
+  _sdata = .;
+  RW_DATA(XCHAL_ICACHE_LINESIZE, PAGE_SIZE, THREAD_SIZE)
+  _edata = .;
+  _xip_data_end = .;
+
+  /* Initialization data: */
+
+  STRUCT_ALIGN();
+
+  _xip_init_data_start = .;
+  __init_begin = .;
+  .init.data :
+  {
+    INIT_DATA
+  }
+  _xip_init_data_end = .;
+  __init_end = .;
+  BSS_SECTION(0, 8192, 0)
+
+  _xip_end = .;
+
+#undef LOAD_OFFSET
+#endif
+
   DWARF_DEBUG
 
   .xt.prop 0 : { KEEP(*(.xt.prop .xt.prop.* .gnu.linkonce.prop.*)) }