From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE73BC46470 for ; Thu, 6 Jun 2019 21:19:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C4C2D208C0 for ; Thu, 6 Jun 2019 21:19:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="N7Uf3Y69" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728256AbfFFVT2 (ORCPT ); Thu, 6 Jun 2019 17:19:28 -0400 Received: from mail-pg1-f193.google.com ([209.85.215.193]:33558 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726873AbfFFVT1 (ORCPT ); Thu, 6 Jun 2019 17:19:27 -0400 Received: by mail-pg1-f193.google.com with SMTP id h17so2069006pgv.0; Thu, 06 Jun 2019 14:19:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=hfZAdBE3k2/ADylfkLAgPJ6OT4ZxvmQkYV/g7J84j0I=; b=N7Uf3Y69HNBwqAe0z/khtYdG+ISOR5MdvbXrYlG9M5DDG7xnpesK1054wTJRgMt4Mv yaheoA7lzB6TkoexneY0Kwqa7wCNw5TQqY/4httbOhTPQdUV/GnKdyH++H92xs1jB7yT 4tF8Fn0+v9w+O/Iyfs27PJdYXKNrJs3o8MjhmT8damPM0DM9Kk+571d0xyx819MH2IHL H4DCgVY5g1jOgHe+/ysl0YiLtfgiiPQYiiR/5Jj/QFR2d6Ysap7krxES3mVXQoJ36SKn 7gtP2tTvHnCzJ3SmVG5sIF7RQp+MmZwvuOSPJGsajxIa+PvotGTi70YX9qtTHDFBDwew ni4A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=hfZAdBE3k2/ADylfkLAgPJ6OT4ZxvmQkYV/g7J84j0I=; b=hDU7YHX8oEY9cNTTvUF30/9VzLelgDu8teMIt+ozRvazO7rSQcYq2DNPthIEkivlhn /DJSZMs+VmCbXnlGB9EahGWYwtxNz3znN+ol6G8ytUiBoZiCLJ1AnG/iQXlvV1ocZz9L JyDqnYZ4xfLSt+YzeonLt3XEirWGt3GmMGqMhTjFy05Qc6ksmufKRo475503OBpPrdu9 n/49y/mJfPnnPozo/Vurvv8fNuLXyMh8XTuXW5qZ8jaUUahFO0go/rVeZ4FjhJ1qkGwz +F84IIcpCz1A87ypbu/pYtTun7/7sDWhPgKaI0cyJTyq9y4clo1IlzuzhDVO1pG9g/sq 6qfA== X-Gm-Message-State: APjAAAUU3XR6RECrqdieLKHPcAYTrzQzu/z0hm0tt4SVO+3iw6uZlLpv kaSxCj6bl+gOI3l/WulfIG0= X-Google-Smtp-Source: APXvYqy4Sd68ZM5XBvSech+lcV4IEPhX+RiIVIh3vx4M9PfZKVmPqrA40LZLl46oJs6VBlSnhSXjPg== X-Received: by 2002:a17:90a:bb8a:: with SMTP id v10mr1934526pjr.78.1559855966636; Thu, 06 Jun 2019 14:19:26 -0700 (PDT) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id b16sm86668pfd.12.2019.06.06.14.19.25 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 06 Jun 2019 14:19:26 -0700 (PDT) Date: Thu, 6 Jun 2019 14:19:25 -0700 From: Guenter Roeck To: Jerry Hoemann Cc: wim@linux-watchdog.org, linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org, mironov.ivan@gmail.com, rasmus.villemoes@prevas.dk Subject: Re: [PATCH 4/6] watchdog/hpwdt: Add module parameter kdumptimeout. Message-ID: <20190606211925.GC1299@roeck-us.net> References: <1558126783-4877-1-git-send-email-jerry.hoemann@hpe.com> <1558126783-4877-5-git-send-email-jerry.hoemann@hpe.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1558126783-4877-5-git-send-email-jerry.hoemann@hpe.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 17, 2019 at 02:59:41PM -0600, Jerry Hoemann wrote: > Instead of unconditionally stopping the watchdog timer after receipt of > a pretimeout NMI, reprogram the timeout based upon module parameter > kdumptimeout. > > The provides a more flexible override than the depricated allow_kdump. > > Signed-off-by: Jerry Hoemann Reviewed-by: Guenter Roeck > --- > drivers/watchdog/hpwdt.c | 27 ++++++++++++++++++++++++--- > 1 file changed, 24 insertions(+), 3 deletions(-) > > diff --git a/drivers/watchdog/hpwdt.c b/drivers/watchdog/hpwdt.c > index aa4101c..dc65006 100644 > --- a/drivers/watchdog/hpwdt.c > +++ b/drivers/watchdog/hpwdt.c > @@ -29,7 +29,8 @@ > #define HPWDT_VERSION "2.0.2" > #define SECS_TO_TICKS(secs) ((secs) * 1000 / 128) > #define TICKS_TO_SECS(ticks) ((ticks) * 128 / 1000) > -#define HPWDT_MAX_TIMER TICKS_TO_SECS(65535) > +#define HPWDT_MAX_TICKS 65535 > +#define HPWDT_MAX_TIMER TICKS_TO_SECS(HPWDT_MAX_TICKS) > #define DEFAULT_MARGIN 30 > #define PRETIMEOUT_SEC 9 > > @@ -37,6 +38,7 @@ > static unsigned int soft_margin = DEFAULT_MARGIN; /* in seconds */ > static bool nowayout = WATCHDOG_NOWAYOUT; > static bool pretimeout = IS_ENABLED(CONFIG_HPWDT_NMI_DECODING); > +static int kdumptimeout = -1; > > static void __iomem *pci_mem_addr; /* the PCI-memory address */ > static unsigned long __iomem *hpwdt_nmistat; > @@ -56,6 +58,7 @@ > {0}, /* terminate list */ > }; > > +static struct watchdog_device hpwdt_dev; > /* > * Watchdog operations > */ > @@ -94,12 +97,18 @@ static int hpwdt_stop_core(struct watchdog_device *wdd) > return 0; > } > > +static void hpwdt_ping_ticks(int val) > +{ > + val = min(val, HPWDT_MAX_TICKS); > + iowrite16(val, hpwdt_timer_reg); > +} > + > static int hpwdt_ping(struct watchdog_device *wdd) > { > int reload = SECS_TO_TICKS(min(wdd->timeout, wdd->max_hw_heartbeat_ms/1000)); > > dev_dbg(wdd->parent, "ping watchdog 0x%08x:0x%08x\n", wdd->timeout, reload); > - iowrite16(reload, hpwdt_timer_reg); > + hpwdt_ping_ticks(reload); > > return 0; > } > @@ -175,7 +184,14 @@ static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs) > if (ilo5 && !pretimeout && !mynmi) > return NMI_DONE; > > - hpwdt_stop(); > + if (kdumptimeout < 0) > + hpwdt_stop(); > + else if (kdumptimeout == 0) > + ; > + else { > + unsigned int val = max((unsigned int)kdumptimeout, hpwdt_dev.timeout); > + hpwdt_ping_ticks(SECS_TO_TICKS(val)); > + } > > hex_byte_pack(panic_msg, mynmi); > nmi_panic(regs, panic_msg); > @@ -328,6 +344,7 @@ static int hpwdt_init_one(struct pci_dev *dev, > pretimeout = 0; > } > hpwdt_dev.pretimeout = pretimeout ? PRETIMEOUT_SEC : 0; > + kdumptimeout = min(kdumptimeout, HPWDT_MAX_TIMER); > > hpwdt_dev.parent = &dev->dev; > retval = watchdog_register_device(&hpwdt_dev); > @@ -342,6 +359,7 @@ static int hpwdt_init_one(struct pci_dev *dev, > hpwdt_dev.timeout, nowayout); > dev_info(&dev->dev, "pretimeout: %s.\n", > pretimeout ? "on" : "off"); > + dev_info(&dev->dev, "kdumptimeout: %d.\n", kdumptimeout); > > if (dev->subsystem_vendor == PCI_VENDOR_ID_HP_3PAR) > ilo5 = true; > @@ -387,6 +405,9 @@ static void hpwdt_exit(struct pci_dev *dev) > MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" > __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); > > +module_param(kdumptimeout, int, 0444); > +MODULE_PARM_DESC(kdumptimeout, "Timeout applied for crash kernel transition in seconds"); > + > #ifdef CONFIG_HPWDT_NMI_DECODING > module_param(pretimeout, bool, 0); > MODULE_PARM_DESC(pretimeout, "Watchdog pretimeout enabled");