Hi Greg,
* gregkh@xxxxxxxxxxxxxxxxxxx <gregkh@xxxxxxxxxxxxxxxxxxx>:
>
> The patch below does not apply to the 5.15-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@xxxxxxxxxxxxxxx>.
Please apply below patch instead to v5.15-stable.
Thanks!
Helge
>From 7dacfca67135dc703df89d273553d8f5259776ce Mon Sep 17 00:00:00 2001
From: Helge Deller <deller@xxxxxx>
Date: Mon, 9 May 2022 18:13:29 +0200
Subject: [PATCH] Revert "parisc: Mark sched_clock unstable only if clocks are
not syncronized"
This backport reverts clock changes which made the Linux internal clock
unreliable on 32- and 64-bit SMP kernels.
This patch brings the clock code in sync with upstream v5.18-rc6.
Signed-off-by: Helge Deller <deller@xxxxxx>
Noticed-by: John David Anglin <dave.anglin@xxxxxxxx>
diff --git a/arch/parisc/kernel/setup.c b/arch/parisc/kernel/setup.c
index cceb09855e03..3fb86ee507dd 100644
--- a/arch/parisc/kernel/setup.c
+++ b/arch/parisc/kernel/setup.c
@@ -150,6 +150,8 @@ void __init setup_arch(char **cmdline_p)
#ifdef CONFIG_PA11
dma_ops_init();
#endif
+
+ clear_sched_clock_stable();
}
/*
diff --git a/arch/parisc/kernel/time.c b/arch/parisc/kernel/time.c
index 061119a56fbe..d8e59a1000ab 100644
--- a/arch/parisc/kernel/time.c
+++ b/arch/parisc/kernel/time.c
@@ -249,13 +249,9 @@ void __init time_init(void)
static int __init init_cr16_clocksource(void)
{
/*
- * The cr16 interval timers are not syncronized across CPUs, even if
- * they share the same socket.
+ * The cr16 interval timers are not synchronized across CPUs.
*/
if (num_online_cpus() > 1 && !running_on_qemu) {
- /* mark sched_clock unstable */
- clear_sched_clock_stable();
-
clocksource_cr16.name = "cr16_unstable";
clocksource_cr16.flags = CLOCK_SOURCE_UNSTABLE;
clocksource_cr16.rating = 0;
