From: Tianyu Lan Tianyu.Lan@microsoft.com
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@microsoft.com Signed-off-by: Tianyu Lan Tianyu.Lan@microsoft.com Link: https://lore.kernel.org/r/20200406155331.2105-6-Tianyu.Lan@microsoft.com Signed-off-by: Wei Liu wei.liu@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- 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. */