Merge tag 'v4.13-rc1' into fixes

The fixes branch is based off a random pre-rc1 commit, because we had
some fixes that needed to go in before rc1 was released.

However we now need to fix some code that went in after that point, but
before rc1, so merge rc1 to get that code into fixes so we can fix it!

4 files changed, 26 insertions, 14 deletions

diff --git a/arch/um/kernel/physmem.c b/arch/um/kernel/physmem.c
index 4c9861b421fd..f02596e9931d 100644
--- a/arch/um/kernel/physmem.c
+++ b/arch/um/kernel/physmem.c
@@ -89,8 +89,8 @@ void __init setup_physmem(unsigned long start, unsigned long reserve_end,
 	offset = uml_reserved - uml_physmem;
 	map_size = len - offset;
 	if(map_size <= 0) {
-		printf("Too few physical memory! Needed=%d, given=%d\n",
-		       offset, len);
+		os_warn("Too few physical memory! Needed=%lu, given=%lu\n",
+			offset, len);
 		exit(1);
 	}
 
@@ -99,9 +99,9 @@ void __init setup_physmem(unsigned long start, unsigned long reserve_end,
 	err = os_map_memory((void *) uml_reserved, physmem_fd, offset,
 			    map_size, 1, 1, 1);
 	if (err < 0) {
-		printf("setup_physmem - mapping %ld bytes of memory at 0x%p "
-		       "failed - errno = %d\n", map_size,
-		       (void *) uml_reserved, err);
+		os_warn("setup_physmem - mapping %ld bytes of memory at 0x%p "
+			"failed - errno = %d\n", map_size,
+			(void *) uml_reserved, err);
 		exit(1);
 	}
 
diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c
index 59158871b9fc..4e6fcb32620f 100644
--- a/arch/um/kernel/trap.c
+++ b/arch/um/kernel/trap.c
@@ -183,6 +183,16 @@ void fatal_sigsegv(void)
 	os_dump_core();
 }
 
+/**
+ * segv_handler() - the SIGSEGV handler
+ * @sig:	the signal number
+ * @unused_si:	the signal info struct; unused in this handler
+ * @regs:	the ptrace register information
+ *
+ * The handler first extracts the faultinfo from the UML ptrace regs struct.
+ * If the userfault did not happen in an UML userspace process, bad_segv is called.
+ * Otherwise the signal did happen in a cloned userspace process, handle it.
+ */
 void segv_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
 {
 	struct faultinfo * fi = UPT_FAULTINFO(regs);
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index 7b5640117325..f433690b9b37 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -34,7 +34,7 @@ static char __initdata command_line[COMMAND_LINE_SIZE] = { 0 };
 static void __init add_arg(char *arg)
 {
 	if (strlen(command_line) + strlen(arg) + 1 > COMMAND_LINE_SIZE) {
-		printf("add_arg: Too many command line arguments!\n");
+		os_warn("add_arg: Too many command line arguments!\n");
 		exit(1);
 	}
 	if (strlen(command_line) > 0)
@@ -120,6 +120,7 @@ static const char *usage_string =
 
 static int __init uml_version_setup(char *line, int *add)
 {
+	/* Explicitly use printf() to show version in stdout */
 	printf("%s\n", init_utsname()->release);
 	exit(0);
 
@@ -148,8 +149,8 @@ __uml_setup("root=", uml_root_setup,
 
 static int __init no_skas_debug_setup(char *line, int *add)
 {
-	printf("'debug' is not necessary to gdb UML in skas mode - run \n");
-	printf("'gdb linux'\n");
+	os_warn("'debug' is not necessary to gdb UML in skas mode - run\n");
+	os_warn("'gdb linux'\n");
 
 	return 0;
 }
@@ -165,6 +166,7 @@ static int __init Usage(char *line, int *add)
 
 	printf(usage_string, init_utsname()->release);
 	p = &__uml_help_start;
+	/* Explicitly use printf() to show help in stdout */
 	while (p < &__uml_help_end) {
 		printf("%s", *p);
 		p++;
@@ -283,8 +285,8 @@ int __init linux_main(int argc, char **argv)
 
 	diff = UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
 	if (diff > 1024 * 1024) {
-		printf("Adding %ld bytes to physical memory to account for "
-		       "exec-shield gap\n", diff);
+		os_info("Adding %ld bytes to physical memory to account for "
+			"exec-shield gap\n", diff);
 		physmem_size += UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
 	}
 
@@ -324,8 +326,8 @@ int __init linux_main(int argc, char **argv)
 	end_vm = start_vm + virtmem_size;
 
 	if (virtmem_size < physmem_size)
-		printf("Kernel virtual memory size shrunk to %lu bytes\n",
-		       virtmem_size);
+		os_info("Kernel virtual memory size shrunk to %lu bytes\n",
+			virtmem_size);
 
 	os_flush_stdout();
 
diff --git a/arch/um/kernel/umid.c b/arch/um/kernel/umid.c
index f6cc3bd61781..10bf4aca529f 100644
--- a/arch/um/kernel/umid.c
+++ b/arch/um/kernel/umid.c
@@ -16,14 +16,14 @@ static int __init set_umid_arg(char *name, int *add)
 	int err;
 
 	if (umid_inited) {
-		printf("umid already set\n");
+		os_warn("umid already set\n");
 		return 0;
 	}
 
 	*add = 0;
 	err = set_umid(name);
 	if (err == -EEXIST)
-		printf("umid '%s' already in use\n", name);
+		os_warn("umid '%s' already in use\n", name);
 	else if (!err)
 		umid_inited = 1;