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
  ...

1 files changed, 16 insertions, 2 deletions

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)