This is a note to let you know that I've just added the patch titled
parisc: Use cr16 interval timers unconditionally on qemu
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
parisc-use-cr16-interval-timers-unconditionally-on-qemu.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 5ffa8518851f1401817c15d2a7eecc0373c26ff9 Mon Sep 17 00:00:00 2001
From: Helge Deller <deller@xxxxxx>
Date: Fri, 12 Jan 2018 22:44:00 +0100
Subject: parisc: Use cr16 interval timers unconditionally on qemu
From: Helge Deller <deller@xxxxxx>
commit 5ffa8518851f1401817c15d2a7eecc0373c26ff9 upstream.
When running on qemu we know that the (emulated) cr16 cpu-internal
clocks are syncronized. So let's use them unconditionally on qemu.
Signed-off-by: Helge Deller <deller@xxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # 4.14+
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/parisc/include/asm/processor.h | 2 ++
arch/parisc/kernel/time.c | 2 +-
2 files changed, 3 insertions(+), 1 deletion(-)
--- a/arch/parisc/include/asm/processor.h
+++ b/arch/parisc/include/asm/processor.h
@@ -323,6 +323,8 @@ extern int _parisc_requires_coherency;
#define parisc_requires_coherency() (0)
#endif
+extern int running_on_qemu;
+
#endif /* __ASSEMBLY__ */
#endif /* __ASM_PARISC_PROCESSOR_H */
--- a/arch/parisc/kernel/time.c
+++ b/arch/parisc/kernel/time.c
@@ -299,7 +299,7 @@ static int __init init_cr16_clocksource(
* The cr16 interval timers are not syncronized across CPUs, so mark
* them unstable and lower rating on SMP systems.
*/
- if (num_online_cpus() > 1) {
+ if (num_online_cpus() > 1 && !running_on_qemu) {
clocksource_cr16.flags = CLOCK_SOURCE_UNSTABLE;
clocksource_cr16.rating = 0;
}
Patches currently in stable-queue which might be from deller@xxxxxx are
queue-4.9/parisc-detect-qemu-earlier-in-boot-process.patch
queue-4.9/parisc-use-cr16-interval-timers-unconditionally-on-qemu.patch
