linux-kernel - [PATCH v0 01/12] x86/mce: Do not use memset to clear the banks bitmaps

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Date:   Thu,  4 Nov 2021 15:40:24 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     Tony Luck <tony.luck@...el.com>
Cc:     X86 ML <x86@...nel.org>, LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH v0 01/12] x86/mce: Do not use memset to clear the banks bitmaps

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

The bitmap is a single unsigned long so no need for the function call.

No functional changes.

Signed-off-by: Borislav Petkov <bp@...e.de>
---
 arch/x86/kernel/cpu/mce/core.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 6ed365337a3b..52d277c955f9 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1340,8 +1340,8 @@ static noinstr void unexpected_machine_check(struct pt_regs *regs)
 noinstr void do_machine_check(struct pt_regs *regs)
 {
 	int worst = 0, order, no_way_out, kill_current_task, lmce;
-	DECLARE_BITMAP(valid_banks, MAX_NR_BANKS);
-	DECLARE_BITMAP(toclear, MAX_NR_BANKS);
+	DECLARE_BITMAP(valid_banks, MAX_NR_BANKS) = { 0 };
+	DECLARE_BITMAP(toclear, MAX_NR_BANKS) = { 0 };
 	struct mca_config *cfg = &mca_cfg;
 	struct mce m, *final;
 	char *msg = NULL;
@@ -1385,7 +1385,6 @@ noinstr void do_machine_check(struct pt_regs *regs)
 	final = this_cpu_ptr(&mces_seen);
 	*final = m;
 
-	memset(valid_banks, 0, sizeof(valid_banks));
 	no_way_out = mce_no_way_out(&m, &msg, valid_banks, regs);
 
 	barrier();
-- 
2.29.2