This is a note to let you know that I've just added the patch titled
rtc: Extend timeout for waiting for UIP to clear to 1s
to the 6.6-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:
rtc-extend-timeout-for-waiting-for-uip-to-clear-to-1s.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From cef9ecc8e938dd48a560f7dd9be1246359248d20 Mon Sep 17 00:00:00 2001
From: Mario Limonciello <mario.limonciello@xxxxxxx>
Date: Mon, 27 Nov 2023 23:36:53 -0600
Subject: rtc: Extend timeout for waiting for UIP to clear to 1s
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From: Mario Limonciello <mario.limonciello@xxxxxxx>
commit cef9ecc8e938dd48a560f7dd9be1246359248d20 upstream.
Specs don't say anything about UIP being cleared within 10ms. They
only say that UIP won't occur for another 244uS. If a long NMI occurs
while UIP is still updating it might not be possible to get valid
data in 10ms.
This has been observed in the wild that around s2idle some calls can
take up to 480ms before UIP is clear.
Adjust callers from outside an interrupt context to wait for up to a
1s instead of 10ms.
Cc: <stable@xxxxxxxxxxxxxxx> # 6.1.y
Fixes: ec5895c0f2d8 ("rtc: mc146818-lib: extract mc146818_avoid_UIP")
Reported-by: Carsten Hatger <xmb8dsv4@xxxxxxxxx>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217626
Tested-by: Mateusz Jończyk <mat.jonczyk@xxxxx>
Reviewed-by: Mateusz Jończyk <mat.jonczyk@xxxxx>
Acked-by: Mateusz Jończyk <mat.jonczyk@xxxxx>
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
Link: https://lore.kernel.org/r/20231128053653.101798-5-mario.limonciello@xxxxxxx
Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kernel/rtc.c | 2 +-
drivers/base/power/trace.c | 2 +-
drivers/rtc/rtc-cmos.c | 2 +-
drivers/rtc/rtc-mc146818-lib.c | 2 +-
4 files changed, 4 insertions(+), 4 deletions(-)
--- a/arch/x86/kernel/rtc.c
+++ b/arch/x86/kernel/rtc.c
@@ -67,7 +67,7 @@ void mach_get_cmos_time(struct timespec6
return;
}
- if (mc146818_get_time(&tm, 10)) {
+ if (mc146818_get_time(&tm, 1000)) {
pr_err("Unable to read current time from RTC\n");
now->tv_sec = now->tv_nsec = 0;
return;
--- a/drivers/base/power/trace.c
+++ b/drivers/base/power/trace.c
@@ -120,7 +120,7 @@ static unsigned int read_magic_time(void
struct rtc_time time;
unsigned int val;
- if (mc146818_get_time(&time, 10) < 0) {
+ if (mc146818_get_time(&time, 1000) < 0) {
pr_err("Unable to read current time from RTC\n");
return 0;
}
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -231,7 +231,7 @@ static int cmos_read_time(struct device
if (!pm_trace_rtc_valid())
return -EIO;
- ret = mc146818_get_time(t, 10);
+ ret = mc146818_get_time(t, 1000);
if (ret < 0) {
dev_err_ratelimited(dev, "unable to read current time\n");
return ret;
--- a/drivers/rtc/rtc-mc146818-lib.c
+++ b/drivers/rtc/rtc-mc146818-lib.c
@@ -93,7 +93,7 @@ EXPORT_SYMBOL_GPL(mc146818_avoid_UIP);
*/
bool mc146818_does_rtc_work(void)
{
- return mc146818_avoid_UIP(NULL, 10, NULL);
+ return mc146818_avoid_UIP(NULL, 1000, NULL);
}
EXPORT_SYMBOL_GPL(mc146818_does_rtc_work);
Patches currently in stable-queue which might be from mario.limonciello@xxxxxxx are
queue-6.6/rtc-extend-timeout-for-waiting-for-uip-to-clear-to-1s.patch
queue-6.6/rtc-mc146818-lib-adjust-failure-return-code-for-mc146818_get_time.patch
queue-6.6/rtc-add-support-for-configuring-the-uip-timeout-for-rtc-reads.patch
queue-6.6/rtc-cmos-use-acpi-alarm-for-non-intel-x86-systems-too.patch
queue-6.6/rtc-adjust-failure-return-code-for-cmos_set_alarm.patch
