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Date: Tue, 13 Oct 2020 07:21:50 +0200
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>,
	Sudip Mukherjee <sudipm.mukherjee@gmail.com>,
	linux-kernel@vger.kernel.org, linux-safety@lists.elisa.tech,
	linux-usb@vger.kernel.org
Subject: Re: [linux-safety] [PATCH] usb: host: ehci-sched: add comment about find_tt() not returning error
Message-ID: <20201013052150.GA330398@kroah.com>
References: <20201011205008.24369-1-sudipm.mukherjee@gmail.com>
 <alpine.DEB.2.21.2010121550300.6487@felia>
 <20201012145710.GA631710@rowland.harvard.edu>
 <alpine.DEB.2.21.2010121659040.6487@felia>
 <20201012160013.GA632789@rowland.harvard.edu>
 <alpine.DEB.2.21.2010122008370.17866@felia>
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On Mon, Oct 12, 2020 at 08:17:34PM +0200, Lukas Bulwahn wrote:
> > If you are suggesting some sort of special code annotation that the tool 
> > would understand, I am open to that.  But I'm not aware of any even 
> > vaguely standard way of marking up a particular function call to 
> > indicate it will not return an error.
> 
> I cannot yet say if some annotation would work, we, Sudip and me, need to 
> investigate. It could be that something like, assert(!IS_ERR(tt)), is 
> sufficient to let the tools know that they can safely assume that the 
> path they are complaining about is not possible.
> 
> We could make the assert() a nop, so it would not effect the resulting 
> object code in any way.

Things like assert() have been rejected numberous times in the past in
the kernel, good luck with that :)

greg k-h