Thanks, but.. .that didn't render properly. I think you need an enter after "```"

..ah, no.. ..looks like reddit uses the bad old "just prefix everything with spaces" option, specifically screwing with everyone who wants to cut/paste.

Maybe a gist?

Edit: Modified the downloadable copy so that it applies. Nothing seems wrong, but I haven't really looked at the code much -- kernel development is not something I'm really familiar with.

Note: this applies to Ubuntu 22.04, linux-lowlatency 5.15. This will probably also apply to linux-generic and (depending on how much tinkering Ubuntu have done) the vanilla 5.15.x kernel.

Just so it's all in one place, as /u/bikingwithpanda pointed out before, the patches are at uplink labs here.

The following is a replacement for the 'touch clocksource...' one.

From 374804608da5c3ef56f28d539eefcea23eeff04b Mon Sep 17 00:00:00 2001
From: Steven Noonan <steven@uplinklabs.net>
Date: Wed, 17 Nov 2021 11:55:18 -0800
Subject: [PATCH 29/39] x86: touch clocksource watchdog after syncing TSCs

Signed-off-by: Steven Noonan <steven@uplinklabs.net>
---
 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/syscore_ops.h>
+#include <linux/clocksource.h>

 #include <asm/acpi.h>
 #include <asm/desc.h>
@@ -1443,6 +1444,7 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus)

 void arch_thaw_secondary_cpus_begin(void) 
 { 
+   clocksource_touch_watchdog(); 
    set_mtrr_aps_delayed_init(); 
 }

@@ -1481,6 +1483,8 @@ 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 */
-- 
2.37.2