[PATCH 5.15 103/135] Revert "parisc: Mark sched_clock unstable only if clocks are not syncronized"

Greg Kroah-Hartman
2022-05-10T14:18:55Z

From: Helge Deller <deller@gmx.de>

commit 7962c0896429af2a0e00ec6bc15d992536453b2d upstream.

This reverts commit d97180ad68bdb7ee10f327205a649bc2f558741d.

It triggers RCU stalls at boot with a 32-bit kernel.

Signed-off-by: Helge Deller <deller@gmx.de>
Noticed-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # v5.15+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/parisc/kernel/setup.c | 2 ++
arch/parisc/kernel/time.c | 6 +-----
2 files changed, 3 insertions(+), 5 deletions(-)

--- 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();
}

/*
--- 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;