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From:   Muhammad Usama Anjum <usama.anjum@collabora.com>
To:     Jonathan Corbet <corbet@lwn.net>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)),
        "H. Peter Anvin" <hpa@zytor.com>,
        linux-doc@vger.kernel.org (open list:DOCUMENTATION),
        linux-kernel@vger.kernel.org (open list)
Cc:     Steven Noonan <steven@uplinklabs.net>, usama.anjum@collabora.com,
        kernel@collabora.com
Subject: [PATCH 2/3] x86: touch clocksource watchdog after syncing TSCs
Date:   Mon,  8 Aug 2022 16:39:53 +0500
Message-Id: <20220808113954.345579-2-usama.anjum@collabora.com>
In-Reply-To: <20220808113954.345579-1-usama.anjum@collabora.com>
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From: Steven Noonan <steven@uplinklabs.net>

Update watchdog after syncing the TSCs of all the CPUs. This is needed
to avoid getting TSC clocksource marked as unstable after syncing them.

Signed-off-by: Steven Noonan <steven@uplinklabs.net>
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
---
 arch/x86/kernel/smpboot.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index f24227bc3220..4b3a03004a1f 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -56,6 +56,7 @@
 #include <linux/numa.h>
 #include <linux/pgtable.h>
 #include <linux/overflow.h>
+#include <linux/clocksource.h>
 
 #include <asm/acpi.h>
 #include <asm/desc.h>
@@ -1444,6 +1445,7 @@ void arch_thaw_secondary_cpus_begin(void)
 
 void arch_thaw_secondary_cpus_end(void)
 {
+	clocksource_touch_watchdog();
 	mtrr_aps_init();
 }
 
@@ -1477,6 +1479,8 @@ void __init native_smp_cpus_done(unsigned int max_cpus)
 {
 	pr_debug("Boot done\n");
 
+	clocksource_touch_watchdog();
+
 	calculate_max_logical_packages();
 
 	/* XXX for now assume numa-in-package and hybrid don't overlap */
-- 
2.30.2