[PATCH 1/6] x86: mce: no need to check return value of debugfs_create functions

[Greg Kroah-Hartman]

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: <x86@xxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx>
Cc: Pu Wen <puwen@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 arch/x86/kernel/cpu/mce/core.c     | 15 ++++---------
 arch/x86/kernel/cpu/mce/inject.c   | 34 +++++-------------------------
 arch/x86/kernel/cpu/mce/severity.c | 14 +++---------
 3 files changed, 12 insertions(+), 51 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 672c7225cb1b..1f13f9032a8a 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -2457,22 +2457,15 @@ static int fake_panic_set(void *data, u64 val)
 DEFINE_SIMPLE_ATTRIBUTE(fake_panic_fops, fake_panic_get,
 			fake_panic_set, "%llu\n");
 
-static int __init mcheck_debugfs_init(void)
+static void __init mcheck_debugfs_init(void)
 {
-	struct dentry *dmce, *ffake_panic;
+	struct dentry *dmce;
 
 	dmce = mce_get_debugfs_dir();
-	if (!dmce)
-		return -ENOMEM;
-	ffake_panic = debugfs_create_file("fake_panic", 0444, dmce, NULL,
-					  &fake_panic_fops);
-	if (!ffake_panic)
-		return -ENOMEM;
-
-	return 0;
+	debugfs_create_file("fake_panic", 0444, dmce, NULL, &fake_panic_fops);
 }
 #else
-static int __init mcheck_debugfs_init(void) { return -EINVAL; }
+static void __init mcheck_debugfs_init(void) { }
 #endif
 
 DEFINE_STATIC_KEY_FALSE(mcsafe_key);
diff --git a/arch/x86/kernel/cpu/mce/inject.c b/arch/x86/kernel/cpu/mce/inject.c
index 8492ef7d9015..0f5b6c57ffde 100644
--- a/arch/x86/kernel/cpu/mce/inject.c
+++ b/arch/x86/kernel/cpu/mce/inject.c
@@ -648,7 +648,6 @@ static const struct file_operations readme_fops = {
 
 static struct dfs_node {
 	char *name;
-	struct dentry *d;
 	const struct file_operations *fops;
 	umode_t perm;
 } dfs_fls[] = {
@@ -662,7 +661,7 @@ static struct dfs_node {
 	{ .name = "README",	.fops = &readme_fops, .perm = S_IRUSR | S_IRGRP | S_IROTH },
 };
 
-static int __init debugfs_init(void)
+static void __init debugfs_init(void)
 {
 	unsigned int i;
 	u64 cap;
@@ -671,30 +670,11 @@ static int __init debugfs_init(void)
 	n_banks = cap & MCG_BANKCNT_MASK;
 
 	dfs_inj = debugfs_create_dir("mce-inject", NULL);
-	if (!dfs_inj)
-		return -EINVAL;
-
-	for (i = 0; i < ARRAY_SIZE(dfs_fls); i++) {
-		dfs_fls[i].d = debugfs_create_file(dfs_fls[i].name,
-						    dfs_fls[i].perm,
-						    dfs_inj,
-						    &i_mce,
-						    dfs_fls[i].fops);
-
-		if (!dfs_fls[i].d)
-			goto err_dfs_add;
-	}
-
-	return 0;
 
-err_dfs_add:
-	while (i-- > 0)
-		debugfs_remove(dfs_fls[i].d);
+	for (i = 0; i < ARRAY_SIZE(dfs_fls); i++)
+		debugfs_create_file(dfs_fls[i].name, dfs_fls[i].perm, dfs_inj,
+				    &i_mce, dfs_fls[i].fops);
 
-	debugfs_remove(dfs_inj);
-	dfs_inj = NULL;
-
-	return -ENODEV;
 }
 
 static int __init inject_init(void)
@@ -704,11 +684,7 @@ static int __init inject_init(void)
 	if (!alloc_cpumask_var(&mce_inject_cpumask, GFP_KERNEL))
 		return -ENOMEM;
 
-	err = debugfs_init();
-	if (err) {
-		free_cpumask_var(mce_inject_cpumask);
-		return err;
-	}
+	debugfs_init();
 
 	register_nmi_handler(NMI_LOCAL, mce_raise_notify, 0, "mce_notify");
 	mce_register_injector_chain(&inject_nb);
diff --git a/arch/x86/kernel/cpu/mce/severity.c b/arch/x86/kernel/cpu/mce/severity.c
index dc3e26e905a3..a2d297981b8a 100644
--- a/arch/x86/kernel/cpu/mce/severity.c
+++ b/arch/x86/kernel/cpu/mce/severity.c
@@ -399,21 +399,13 @@ static const struct file_operations severities_coverage_fops = {
 
 static int __init severities_debugfs_init(void)
 {
-	struct dentry *dmce, *fsev;
+	struct dentry *dmce;
 
 	dmce = mce_get_debugfs_dir();
-	if (!dmce)
-		goto err_out;
-
-	fsev = debugfs_create_file("severities-coverage", 0444, dmce, NULL,
-				   &severities_coverage_fops);
-	if (!fsev)
-		goto err_out;
 
+	debugfs_create_file("severities-coverage", 0444, dmce, NULL,
+			    &severities_coverage_fops);
 	return 0;
-
-err_out:
-	return -ENOMEM;
 }
 late_initcall(severities_debugfs_init);
 #endif /* CONFIG_DEBUG_FS */
-- 
2.20.1