This is a note to let you know that I've just added the patch titled
x86/Hyper-V: Report crash register data when sysctl_record_panic_msg is not set
to the 5.4-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:
x86-hyper-v-report-crash-register-data-when-sysctl_record_panic_msg-is-not-set.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 040026df7088c56ccbad28f7042308f67bde63df Mon Sep 17 00:00:00 2001
From: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx>
Date: Mon, 6 Apr 2020 08:53:30 -0700
Subject: x86/Hyper-V: Report crash register data when sysctl_record_panic_msg is not set
From: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx>
commit 040026df7088c56ccbad28f7042308f67bde63df upstream.
When sysctl_record_panic_msg is not set, the panic will
not be reported to Hyper-V via hyperv_report_panic_msg().
So the crash should be reported via hyperv_report_panic().
Fixes: 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic")
Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
Signed-off-by: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20200406155331.2105-6-Tianyu.Lan@xxxxxxxxxxxxx
Signed-off-by: Wei Liu <wei.liu@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/hv/vmbus_drv.c | 23 ++++++++++++++---------
1 file changed, 14 insertions(+), 9 deletions(-)
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -48,6 +48,18 @@ static int hyperv_cpuhp_online;
static void *hv_panic_page;
+/*
+ * Boolean to control whether to report panic messages over Hyper-V.
+ *
+ * It can be set via /proc/sys/kernel/hyperv/record_panic_msg
+ */
+static int sysctl_record_panic_msg = 1;
+
+static int hyperv_report_reg(void)
+{
+ return !sysctl_record_panic_msg || !hv_panic_page;
+}
+
static int hyperv_panic_event(struct notifier_block *nb, unsigned long val,
void *args)
{
@@ -61,7 +73,7 @@ static int hyperv_panic_event(struct not
* the notification here.
*/
if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE
- && !hv_panic_page) {
+ && hyperv_report_reg()) {
regs = current_pt_regs();
hyperv_report_panic(regs, val);
}
@@ -79,7 +91,7 @@ static int hyperv_die_event(struct notif
* doing hyperv_report_panic_msg() later with kmsg data, don't do
* the notification here.
*/
- if (!hv_panic_page)
+ if (hyperv_report_reg())
hyperv_report_panic(regs, val);
return NOTIFY_DONE;
}
@@ -1262,13 +1274,6 @@ static void vmbus_isr(void)
}
/*
- * Boolean to control whether to report panic messages over Hyper-V.
- *
- * It can be set via /proc/sys/kernel/hyperv/record_panic_msg
- */
-static int sysctl_record_panic_msg = 1;
-
-/*
* Callback from kmsg_dump. Grab as much as possible from the end of the kmsg
* buffer and call into Hyper-V to transfer the data.
*/
Patches currently in stable-queue which might be from Tianyu.Lan@xxxxxxxxxxxxx are
queue-5.4/x86-hyper-v-unload-vmbus-channel-in-hv-panic-callback.patch
queue-5.4/x86-hyper-v-trigger-crash-enlightenment-only-once-during-system-crash.patch
queue-5.4/x86-hyper-v-report-crash-register-data-or-kmsg-before-running-crash-kernel.patch
queue-5.4/x86-hyper-v-report-crash-register-data-when-sysctl_record_panic_msg-is-not-set.patch
queue-5.4/x86-hyper-v-report-crash-data-in-die-when-panic_on_oops-is-set.patch
