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Subject: [PATCH 1/2] module: merge repetitive strings in module_sig_check()
From:   Sergey Shtylyov <s.shtylyov@omprussia.ru>
To:     Jessica Yu <jeyu@kernel.org>, <linux-kernel@vger.kernel.org>
References: <789a4e5c-8efd-bb1c-86e2-eed8b2b7b0af@omprussia.ru>
Organization: Open Mobile Platform, LLC
Message-ID: <4c4a3fa0-3eee-6cca-947c-9d01e3eb2a8a@omprussia.ru>
Date:   Tue, 13 Oct 2020 23:34:09 +0300
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The 'reason' variable in module_sig_check() points to 3 strings across
the *switch* statement, all needlessly starting with the same text.  Let's
put as much of the starting text as we can into the pr_notice() call (this
includes some rewording of the 1st message) -- it saves 37 bytes of object
code (x86 gcc 10.2.1).

Signed-off-by: Sergey Shtylyov <s.shtylyov@omprussia.ru>

---
 kernel/module.c |    9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

Index: linux/kernel/module.c
===================================================================
--- linux.orig/kernel/module.c
+++ linux/kernel/module.c
@@ -2906,16 +2906,17 @@ static int module_sig_check(struct load_
 		 * enforcing, certain errors are non-fatal.
 		 */
 	case -ENODATA:
-		reason = "Loading of unsigned module";
+		reason = "no signature";
 		goto decide;
 	case -ENOPKG:
-		reason = "Loading of module with unsupported crypto";
+		reason = "unsupported crypto";
 		goto decide;
 	case -ENOKEY:
-		reason = "Loading of module with unavailable key";
+		reason = "unavailable key";
 	decide:
 		if (is_module_sig_enforced()) {
-			pr_notice("%s: %s is rejected\n", info->name, reason);
+			pr_notice("%s: loading of module with %s is rejected\n",
+				  info->name, reason);
 			return -EKEYREJECTED;
 		}