From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Sender: rtc-linux@googlegroups.com MIME-Version: 1.0 Received: from mail-pf0-f182.google.com (mail-pf0-f182.google.com. [209.85.192.182]) by gmr-mx.google.com with ESMTPS id z4si229184pam.0.2016.08.02.00.27.08 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 02 Aug 2016 00:27:08 -0700 (PDT) Received: by mail-pf0-f182.google.com with SMTP id x72so63743638pfd.2 for ; Tue, 02 Aug 2016 00:27:08 -0700 (PDT) From: Pratyush Anand To: mingo@kernel.org, alexandre.belloni@free-electrons.com, tglx@linutronix.de, hpa@zytor.com, x86@kernel.org Cc: rtc-linux@googlegroups.com, linux-kernel@vger.kernel.org, prarit@redhat.com, dyoung@redhat.com, a.zummo@towertech.it, Pratyush Anand Subject: [rtc-linux] [PATCH V2 0/2] rtc-cmos: Workaround unwanted interrupt generation Date: Tue, 2 Aug 2016 12:56:58 +0530 Message-Id: Reply-To: rtc-linux@googlegroups.com Content-Type: text/plain; charset=UTF-8 List-ID: List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , We have observed on few machines with rtc-cmos device that hpet_rtc_interrupt() is called before cmos_do_probe() could call hpet_rtc_timer_init(). It has not been observed during normal boot/reboot of machines. It *sometime* happens when system is booted with kdump secondary kernel. So, neither hpet_default_delta nor hpet_t1_cmp is initialized by the time interrupt is raised in the given situation. Therefore while loop of hpet_cnt_ahead() in hpet_rtc_timer_reinit() never completes. This leads to "NMI watchdog: Watchdog detected hard LOCKUP on cpu 0". These patch set initializes hpet_default_delta and hpet_t1_cmp before interrupt can be raised. Changes since RFC: - Commit log of patches has been improved. - RFCs were here: https://lkml.org/lkml/2016/6/21/35 Pratyush Anand (2): rtc/hpet: Factorize hpet_rtc_timer_init() rtc/rtc-cmos: Initialize software counters before irq is registered arch/x86/include/asm/hpet.h | 2 ++ arch/x86/kernel/hpet.c | 41 +++++++++++++++++++++++++++++++++++------ drivers/rtc/rtc-cmos.c | 13 ++++++++++++- 3 files changed, 49 insertions(+), 7 deletions(-) -- 2.5.5 -- You received this message because you are subscribed to "rtc-linux". Membership options at http://groups.google.com/group/rtc-linux . Please read http://groups.google.com/group/rtc-linux/web/checklist before submitting a driver. --- You received this message because you are subscribed to the Google Groups "rtc-linux" group. To unsubscribe from this group and stop receiving emails from it, send an email to rtc-linux+unsubscribe@googlegroups.com. For more options, visit https://groups.google.com/d/optout.