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From: Sascha Hauer <s.hauer@pengutronix.de>
To: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: barebox@lists.infradead.org
Subject: Re: [PATCH] serial: lpuart: Avoid division by zero when requested baudrate is
Date: Mon, 14 May 2018 09:14:56 +0200	[thread overview]
Message-ID: <20180514071456.qknyha5bsl6gbkk4@pengutronix.de> (raw)
In-Reply-To: <20180508211502.5476-1-andrew.smirnov@gmail.com>

On Tue, May 08, 2018 at 02:15:02PM -0700, Andrey Smirnov wrote:
> With serdev device support added there's now a corner case where:
> 
>  1. There is a DT node for a serdev device on one of the UARTs
>  2. There is no driver that binds against serdev device's compatibility
>     string
> 
> with 1 and 2 being true it is possible to end up in a situation where
> a particualr UART has not been initalized to any baudrate when
> clock_notifier_call_chain() gets called. This effectively translates
> to
> 
> 	set_baudrate(uart, 0);
> 
> which for LPUART driver result in a division by zero.

This probably leads to a division by zero for most drivers since
dividing by the baudrate is a common pattern. Wouldn't it be better to
catch this is console_set_baudrate()?

Sascha

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  reply	other threads:[~2018-05-14  7:15 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-08 21:15 Andrey Smirnov
2018-05-14  7:14 ` Sascha Hauer [this message]
2018-05-15  0:20   ` Andrey Smirnov
2018-05-15  6:07     ` Sascha Hauer
2018-08-11 19:35       ` Andrey Smirnov
2018-08-13  7:14         ` Sascha Hauer

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