[PATCH 2/7] kernel: Replace get_task_comm() with %pTN

[Yafang Shao]

Since task->comm is guaranteed to be NUL-terminated, we can print it
directly without the need to copye it into a separate buffer. This
simplifies the code and avoids unnecessary operations.

Signed-off-by: Yafang Shao <laoar.shao at gmail.com>
Cc: Serge Hallyn <serge at hallyn.com>
Cc: Thomas Gleixner <tglx at linutronix.de>
Cc: Ingo Molnar <mingo at redhat.com>
Cc: Peter Zijlstra <peterz at infradead.org>
Cc: Darren Hart <dvhart at infradead.org>
Cc: Davidlohr Bueso <dave at stgolabs.net>
Cc: "André Almeida" <andrealmeid at igalia.com>
---
 kernel/capability.c     | 12 ++++--------
 kernel/futex/waitwake.c |  5 ++---
 2 files changed, 6 insertions(+), 11 deletions(-)

diff --git a/kernel/capability.c b/kernel/capability.c
index dac4df77e376..4512cd797f49 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -38,10 +38,8 @@ __setup("no_file_caps", file_caps_disable);
 
 static void warn_legacy_capability_use(void)
 {
-	char name[sizeof(current->comm)];
-
-	pr_info_once("warning: `%s' uses 32-bit capabilities (legacy support in use)\n",
-		     get_task_comm(name, current));
+	pr_info_once("warning: `%pTN' uses 32-bit capabilities (legacy support in use)\n",
+		     current);
 }
 
 /*
@@ -62,10 +60,8 @@ static void warn_legacy_capability_use(void)
 
 static void warn_deprecated_v2(void)
 {
-	char name[sizeof(current->comm)];
-
-	pr_info_once("warning: `%s' uses deprecated v2 capabilities in a way that may be insecure\n",
-		     get_task_comm(name, current));
+	pr_info_once("warning: `%pTN' uses deprecated v2 capabilities in a way that may be insecure\n",
+		     current);
 }
 
 /*
diff --git a/kernel/futex/waitwake.c b/kernel/futex/waitwake.c
index 3a10375d9521..df8f8c85d776 100644
--- a/kernel/futex/waitwake.c
+++ b/kernel/futex/waitwake.c
@@ -210,13 +210,12 @@ static int futex_atomic_op_inuser(unsigned int encoded_op, u32 __user *uaddr)
 
 	if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) {
 		if (oparg < 0 || oparg > 31) {
-			char comm[sizeof(current->comm)];
 			/*
 			 * kill this print and return -EINVAL when userspace
 			 * is sane again
 			 */
-			pr_info_ratelimited("futex_wake_op: %s tries to shift op by %d; fix this program\n",
-					get_task_comm(comm, current), oparg);
+			pr_info_ratelimited("futex_wake_op: %pTN tries to shift op by %d; fix this program\n",
+					    current, oparg);
 			oparg &= 31;
 		}
 		oparg = 1 << oparg;
-- 
2.43.5