linux-kernel - [PATCH 09/22] x86/srso: Simplify exit paths

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Date:   Sun, 20 Aug 2023 18:19:06 -0700
From:   Josh Poimboeuf <jpoimboe@...nel.org>
To:     x86@...nel.org
Cc:     linux-kernel@...r.kernel.org, Borislav Petkov <bp@...en8.de>,
        Peter Zijlstra <peterz@...radead.org>,
        Babu Moger <babu.moger@....com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Sean Christopherson <seanjc@...gle.com>, David.Kaplan@....com,
        Andrew Cooper <andrew.cooper3@...rix.com>,
        Nikolay Borisov <nik.borisov@...e.com>,
        gregkh@...uxfoundation.org, Thomas Gleixner <tglx@...utronix.de>
Subject: [PATCH 09/22] x86/srso: Simplify exit paths

Send all function exit paths through the pred_cmd check to simplify the
control flow and make it more future-proof.

While at it, rename the 'pred_cmd' label to 'out' to make it clear that
it's the exit.

Signed-off-by: Josh Poimboeuf <jpoimboe@...nel.org>
---
 arch/x86/kernel/cpu/bugs.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index e59e09babf8f..da480c089739 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -2407,7 +2407,7 @@ static void __init srso_select_mitigation(void)
 	bool has_microcode = boot_cpu_has(X86_FEATURE_IBPB_BRTYPE);
 
 	if (!boot_cpu_has_bug(X86_BUG_SRSO) || cpu_mitigations_off())
-		goto pred_cmd;
+		goto out;
 
 	if (!has_microcode) {
 		pr_warn("IBPB-extending microcode not applied!\n");
@@ -2419,7 +2419,7 @@ static void __init srso_select_mitigation(void)
 		 */
 		if (boot_cpu_data.x86 < 0x19 && !cpu_smt_possible()) {
 			setup_force_cpu_cap(X86_FEATURE_SRSO_NO);
-			return;
+			goto out;
 		}
 	}
 
@@ -2427,13 +2427,13 @@ static void __init srso_select_mitigation(void)
 		if (has_microcode) {
 			pr_info("Retbleed IBPB mitigation enabled, using same for SRSO\n");
 			srso_mitigation = SRSO_MITIGATION_IBPB;
-			goto pred_cmd;
+			goto out;
 		}
 	}
 
 	switch (srso_cmd) {
 	case SRSO_CMD_OFF:
-		goto pred_cmd;
+		goto out;
 
 	case SRSO_CMD_MICROCODE:
 		if (has_microcode) {
@@ -2489,7 +2489,7 @@ static void __init srso_select_mitigation(void)
 
 	pr_info("%s%s\n", srso_strings[srso_mitigation], (has_microcode ? "" : ", no microcode"));
 
-pred_cmd:
+out:
 	if (boot_cpu_has(X86_FEATURE_SBPB) && srso_mitigation == SRSO_MITIGATION_NONE)
 		x86_pred_cmd = PRED_CMD_SBPB;
 }
-- 
2.41.0