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 6.1-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-6.1 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
MIME-Version: 1.0
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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(-)
diff --git a/arch/x86/kernel/rtc.c b/arch/x86/kernel/rtc.c
index 961ebc7f1872..2e7066980f3e 100644
--- a/arch/x86/kernel/rtc.c
+++ b/arch/x86/kernel/rtc.c
@@ -67,7 +67,7 @@ void mach_get_cmos_time(struct timespec64 *now)
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;
diff --git a/drivers/base/power/trace.c b/drivers/base/power/trace.c
index c2e925357474..cd6e559648b2 100644
--- 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;
}
diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index 468ccd99f218..7d99cd2c37a0 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -231,7 +231,7 @@ static int cmos_read_time(struct device *dev, struct rtc_time *t)
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;
diff --git a/drivers/rtc/rtc-mc146818-lib.c b/drivers/rtc/rtc-mc146818-lib.c
index 4c17b3cef11e..651bf3c279c7 100644
--- 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);
--
2.43.0
Patches currently in stable-queue which might be from mario.limonciello@xxxxxxx are
queue-6.1/rtc-extend-timeout-for-waiting-for-uip-to-clear-to-1s.patch
queue-6.1/rtc-mc146818-lib-adjust-failure-return-code-for-mc146818_get_time.patch
queue-6.1/rtc-add-support-for-configuring-the-uip-timeout-for-rtc-reads.patch
queue-6.1/rtc-cmos-use-acpi-alarm-for-non-intel-x86-systems-too.patch
queue-6.1/rtc-adjust-failure-return-code-for-cmos_set_alarm.patch
