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From: Timo Kokkonen <timo.kokkonen@offcode.fi>
To: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: linux-arm-kernel@lists.infradead.org,
	linux-watchdog@vger.kernel.org, nicolas.ferre@atmel.com,
	alexandre.belloni@free-electrons.com
Subject: Re: [PATCHv3 0/2] watchdog: Introduce "early-timeout-sec" property
Date: Wed, 18 Feb 2015 15:51:07 +0200	[thread overview]
Message-ID: <54E498CB.8010100@offcode.fi> (raw)
In-Reply-To: <20150218141655.0445958d@bbrezillon>

Hi Boris,

Thanks for your comments. I will resend tomorrow!

-Timo

On 18.02.2015 15:16, Boris Brezillon wrote:
> Hi Timo,
>
> Could you send new versions of this in their own thread (not in reply
> to previous versions), and increment the version in patch 1 and 2 ?
>
> Could you also summarize what has changed between each versions in this
> cover letter ?
>
> Best Regards,
>
> Boris
>
> On Wed, 18 Feb 2015 14:57:20 +0200
> Timo Kokkonen <timo.kokkonen@offcode.fi> wrote:
>
>> Currently we have no means to adjust the watchdog behavior on early
>> start up before user space has opened the device. The generic behavior
>> among the watchdog drivers is to not start the watchdog at all (or
>> disable it, if possible, or in case at91sam9_wdt, start a kernel timer
>> that keeps on pinging the watchdog on behalf of user space until a
>> watchdog daemon opens it). This unfortunately opens a time window
>> between starting the driver and starting the user space watchdog
>> daemon where a crash of the kernel or user space might prevent the
>> watchdog from ever resetting the device at all. This is obviously bad
>> on production systems.
>>
>> Introduce a new device tree property that, when set, changes the
>> watchdog driver behavior in such way that there no longer is any
>> window where crash is not caught by the watchdog.
>>
>> This is the third version of this patch. Previous versions of the
>> patch were using an atmel specific property name. This patch uses a
>> generic name instead as the functionality itself has nothing atmel
>> related. I am also introducing watchdog.txt for describing the generic
>> watchdog device tree bindings as there was no such file before.
>>
>> Timo Kokkonen (2):
>>    devicetree: Document generic watchdog properties
>>    at91sam9_wdt: Allow watchdog to reset device at early boot
>>
>>   .../devicetree/bindings/watchdog/watchdog.txt         | 19 +++++++++++++++++++
>>   drivers/watchdog/at91sam9_wdt.c                       |  9 ++++++++-
>>   2 files changed, 27 insertions(+), 1 deletion(-)
>>   create mode 100644 Documentation/devicetree/bindings/watchdog/watchdog.txt
>>
>
>
>


WARNING: multiple messages have this Message-ID (diff)
From: timo.kokkonen@offcode.fi (Timo Kokkonen)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCHv3 0/2] watchdog: Introduce "early-timeout-sec" property
Date: Wed, 18 Feb 2015 15:51:07 +0200	[thread overview]
Message-ID: <54E498CB.8010100@offcode.fi> (raw)
In-Reply-To: <20150218141655.0445958d@bbrezillon>

Hi Boris,

Thanks for your comments. I will resend tomorrow!

-Timo

On 18.02.2015 15:16, Boris Brezillon wrote:
> Hi Timo,
>
> Could you send new versions of this in their own thread (not in reply
> to previous versions), and increment the version in patch 1 and 2 ?
>
> Could you also summarize what has changed between each versions in this
> cover letter ?
>
> Best Regards,
>
> Boris
>
> On Wed, 18 Feb 2015 14:57:20 +0200
> Timo Kokkonen <timo.kokkonen@offcode.fi> wrote:
>
>> Currently we have no means to adjust the watchdog behavior on early
>> start up before user space has opened the device. The generic behavior
>> among the watchdog drivers is to not start the watchdog at all (or
>> disable it, if possible, or in case at91sam9_wdt, start a kernel timer
>> that keeps on pinging the watchdog on behalf of user space until a
>> watchdog daemon opens it). This unfortunately opens a time window
>> between starting the driver and starting the user space watchdog
>> daemon where a crash of the kernel or user space might prevent the
>> watchdog from ever resetting the device at all. This is obviously bad
>> on production systems.
>>
>> Introduce a new device tree property that, when set, changes the
>> watchdog driver behavior in such way that there no longer is any
>> window where crash is not caught by the watchdog.
>>
>> This is the third version of this patch. Previous versions of the
>> patch were using an atmel specific property name. This patch uses a
>> generic name instead as the functionality itself has nothing atmel
>> related. I am also introducing watchdog.txt for describing the generic
>> watchdog device tree bindings as there was no such file before.
>>
>> Timo Kokkonen (2):
>>    devicetree: Document generic watchdog properties
>>    at91sam9_wdt: Allow watchdog to reset device at early boot
>>
>>   .../devicetree/bindings/watchdog/watchdog.txt         | 19 +++++++++++++++++++
>>   drivers/watchdog/at91sam9_wdt.c                       |  9 ++++++++-
>>   2 files changed, 27 insertions(+), 1 deletion(-)
>>   create mode 100644 Documentation/devicetree/bindings/watchdog/watchdog.txt
>>
>
>
>

  reply	other threads:[~2015-02-18 13:51 UTC|newest]

Thread overview: 110+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-10-23 10:40 [PATCH] at91sam9_wdt: Allow watchdog to reset device at early boot Timo Kokkonen
2014-10-23 10:40 ` Timo Kokkonen
2014-11-12  8:20 ` Timo Kokkonen
2014-11-12  8:20   ` Timo Kokkonen
2014-11-13  9:12   ` Nicolas Ferre
2014-11-13  9:12     ` Nicolas Ferre
2014-11-14  8:40     ` Timo Kokkonen
2014-11-14  8:40       ` Timo Kokkonen
2014-11-21 12:23       ` Timo Kokkonen
2014-11-21 12:23         ` Timo Kokkonen
2014-11-27  6:53         ` Timo Kokkonen
2014-11-27  6:53           ` Timo Kokkonen
2014-11-27  9:22           ` Nicolas Ferre
2014-11-27  9:22             ` Nicolas Ferre
2014-11-27 17:23             ` Guenter Roeck
2014-11-27 17:23               ` Guenter Roeck
2014-11-27 19:06               ` Boris Brezillon
2014-11-27 19:06                 ` Boris Brezillon
2014-11-27 19:31                 ` Guenter Roeck
2014-11-27 19:31                   ` Guenter Roeck
2014-11-28  0:30                   ` Alexandre Belloni
2014-11-28  0:30                     ` Alexandre Belloni
2014-11-28  6:40                   ` Timo Kokkonen
2014-11-28  6:40                     ` Timo Kokkonen
2014-11-27 19:00         ` Boris Brezillon
2014-11-27 19:00           ` Boris Brezillon
2014-11-28  6:42           ` Timo Kokkonen
2014-11-28  6:42             ` Timo Kokkonen
2014-12-05 12:57           ` Timo Kokkonen
2014-12-05 12:57             ` Timo Kokkonen
2014-12-05 14:12             ` Boris Brezillon
2014-12-05 14:12               ` Boris Brezillon
2014-12-05 18:42               ` Timo Kokkonen
2014-12-05 18:42                 ` Timo Kokkonen
2014-12-05 19:02                 ` Guenter Roeck
2014-12-05 19:02                   ` Guenter Roeck
2014-12-05 20:32                   ` Timo Kokkonen
2014-12-05 20:32                     ` Timo Kokkonen
2014-12-05 21:39                     ` Guenter Roeck
2014-12-05 21:39                       ` Guenter Roeck
2014-12-06 10:11                       ` Timo Kokkonen
2014-12-06 10:11                         ` Timo Kokkonen
2015-01-13 14:53                         ` Guenter Roeck
2015-01-13 14:53                           ` Guenter Roeck
2015-01-14  6:09                           ` Timo Kokkonen
2015-01-14  6:09                             ` Timo Kokkonen
2015-02-18 12:57                           ` [PATCHv3 0/2] watchdog: Introduce "early-timeout-sec" property Timo Kokkonen
2015-02-18 12:57                             ` Timo Kokkonen
2015-02-18 12:57                             ` [PATCH 1/2] devicetree: Document generic watchdog properties Timo Kokkonen
2015-02-18 12:57                               ` Timo Kokkonen
2015-02-18 12:57                             ` [PATCH 2/2] at91sam9_wdt: Allow watchdog to reset device at early boot Timo Kokkonen
2015-02-18 12:57                               ` Timo Kokkonen
2015-02-18 13:21                               ` Boris Brezillon
2015-02-18 13:21                                 ` Boris Brezillon
2015-02-18 13:59                               ` Guenter Roeck
2015-02-18 13:59                                 ` Guenter Roeck
2015-02-18 14:17                                 ` Boris Brezillon
2015-02-18 14:17                                   ` Boris Brezillon
2015-02-18 14:50                                   ` Guenter Roeck
2015-02-18 14:50                                     ` Guenter Roeck
2015-02-18 16:00                                     ` Alexandre Belloni
2015-02-18 16:00                                       ` Alexandre Belloni
2015-02-18 17:50                                       ` Guenter Roeck
2015-02-18 17:50                                         ` Guenter Roeck
2015-02-18 20:21                                         ` Boris Brezillon
2015-02-18 20:21                                           ` Boris Brezillon
2015-02-19  6:02                                           ` Timo Kokkonen
2015-02-19  6:02                                             ` Timo Kokkonen
2015-02-18 21:11                                       ` Rob Herring
2015-02-18 21:11                                         ` Rob Herring
2015-02-19  6:14                                         ` Timo Kokkonen
2015-02-19  6:14                                           ` Timo Kokkonen
2015-02-20 14:06                                           ` Rob Herring
2015-02-20 14:06                                             ` Rob Herring
2015-02-20 16:28                                             ` Guenter Roeck
2015-02-20 16:28                                               ` Guenter Roeck
2015-02-20 19:43                                               ` Boris Brezillon
2015-02-20 19:43                                                 ` Boris Brezillon
2015-02-20 20:04                                                 ` Guenter Roeck
2015-02-20 20:04                                                   ` Guenter Roeck
2015-02-20  7:48                               ` Jean-Christophe PLAGNIOL-VILLARD
2015-02-20  7:48                                 ` Jean-Christophe PLAGNIOL-VILLARD
2015-02-20  7:51                                 ` Boris Brezillon
2015-02-20  7:51                                   ` Boris Brezillon
2015-02-20 16:33                                   ` Jean-Christophe PLAGNIOL-VILLARD
2015-02-20 16:33                                     ` Jean-Christophe PLAGNIOL-VILLARD
2015-02-20 17:16                                     ` Boris Brezillon
2015-02-20 17:16                                       ` Boris Brezillon
2015-02-20 18:06                                       ` Guenter Roeck
2015-02-20 18:06                                         ` Guenter Roeck
2015-02-23  7:29                                         ` Timo Kokkonen
2015-02-23  7:29                                           ` Timo Kokkonen
2015-02-23  8:51                                           ` Boris Brezillon
2015-02-23  8:51                                             ` Boris Brezillon
2015-02-23  9:11                                             ` Timo Kokkonen
2015-02-23  9:11                                               ` Timo Kokkonen
2015-02-23 16:19                                               ` Guenter Roeck
2015-02-23 16:19                                                 ` Guenter Roeck
2015-02-23 17:10                                                 ` Rob Herring
2015-02-23 17:10                                                   ` Rob Herring
2015-02-23 17:43                                                   ` Guenter Roeck
2015-02-23 17:43                                                     ` Guenter Roeck
2015-02-20  8:00                                 ` Timo Kokkonen
2015-02-20  8:00                                   ` Timo Kokkonen
2015-02-20 16:09                                 ` Guenter Roeck
2015-02-20 16:09                                   ` Guenter Roeck
2015-02-18 13:16                             ` [PATCHv3 0/2] watchdog: Introduce "early-timeout-sec" property Boris Brezillon
2015-02-18 13:16                               ` Boris Brezillon
2015-02-18 13:51                               ` Timo Kokkonen [this message]
2015-02-18 13:51                                 ` Timo Kokkonen

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