linux-kernel - Re: [PATCH v3 char-misc-next] misc: microchip: pci1xxxx: Add OTP/EEPROM driver for the pci1xxxx switch

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 6 Feb 2023 10:41:43 +0100
From:   Greg KH <gregkh@...uxfoundation.org>
To:     Tharunkumar.Pasumarthi@...rochip.com
Cc:     Kumaravel.Thiagarajan@...rochip.com, arnd@...db.de,
        linux-kernel@...r.kernel.org, linux-gpio@...r.kernel.org,
        UNGLinuxDriver@...rochip.com, lkp@...el.com
Subject: Re: [PATCH v3 char-misc-next] misc: microchip: pci1xxxx: Add
 OTP/EEPROM driver for the pci1xxxx switch

On Mon, Feb 06, 2023 at 09:20:51AM +0000, Tharunkumar.Pasumarthi@...rochip.com wrote:
> > From: Greg KH <gregkh@...uxfoundation.org>
> > Sent: Friday, January 20, 2023 4:26 PM
> > To: Kumaravel Thiagarajan - I21417
> > <Kumaravel.Thiagarajan@...rochip.com>
> > > +             dev_err(&priv->pdev->dev,
> > > +                     "EPC_Timeout, EEPROM is unresponsive: %x\n",
> > > + data);
> > 
> > Can this spam the kernel logs?  If so, please rate limit it.
> 
> This print will only come once at max and will not spam logs.
> 
> > > +     delay = msecs_to_jiffies(OTP_RW_TIMEOUT_MILLISECONDS);
> > > +     j0 = jiffies;
> > > +     j1 = j0 + delay;
> > 
> > Are you sure this math works out?  Please use the jiffies math functions
> > instead so you can handle wrapping properly.
> 
> You suggest using any existing APIs to add jiffies to handle wrapping? I am not able 
> to find any such API. Can you please point out API name. 

I have no context here for what you are doing with the math in jiffies,
but that is usually a very odd thing.  If you use the normal timer
functions, you will not have to worry about the wrapping as it is
handled for you, right?

thanks,

greg k-h