linux-kernel - [PATCH 6/6] x86/cpu: Remove "noclflush"

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Date:   Fri, 12 Nov 2021 11:32:46 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     X86 ML <x86@...nel.org>
Cc:     LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH 6/6] x86/cpu: Remove "noclflush"

From: Borislav Petkov <bp@...e.de>

Not really needed anymore and there's clearcpuid=.

Signed-off-by: Borislav Petkov <bp@...e.de>
---
 Documentation/admin-guide/kernel-parameters.txt | 2 --
 arch/x86/kernel/cpu/common.c                    | 8 --------
 2 files changed, 10 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 3a4c3fc88bf1..5239d4ae2b91 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3348,8 +3348,6 @@
 
 	nocache		[ARM]
 
-	noclflush	[BUGS=X86] Don't use the CLFLUSH instruction
-
 	delayacct	[KNL] Enable per-task delay accounting
 
 	nodsp		[SH] Disable hardware DSP at boot time.
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 7e70c54cdff5..9a8ecb388f2f 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1721,14 +1721,6 @@ void identify_secondary_cpu(struct cpuinfo_x86 *c)
 	update_srbds_msr();
 }
 
-static __init int setup_noclflush(char *arg)
-{
-	setup_clear_cpu_cap(X86_FEATURE_CLFLUSH);
-	setup_clear_cpu_cap(X86_FEATURE_CLFLUSHOPT);
-	return 1;
-}
-__setup("noclflush", setup_noclflush);
-
 void print_cpu_info(struct cpuinfo_x86 *c)
 {
 	const char *vendor = NULL;
-- 
2.29.2