Date:   Wed, 24 Nov 2021 09:13:33 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Lizhi Hou <lizhi.hou@xilinx.com>
Cc:     linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org,
        jacmet@sunsite.dk
Subject: Re: [PATCH 1/1] tty: serial: uartlite: allow 64 bit address
Message-ID: <YZ30La8Z7oZEoXFF@kroah.com>
References: <20211123184506.1184561-1-lizhi.hou@xilinx.com>
 <YZ05/73+BhIANNGF@kroah.com>
 <0e212384-396b-f765-be28-f9319c64b5f7@xilinx.com>
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On Tue, Nov 23, 2021 at 12:12:06PM -0800, Lizhi Hou wrote:
> 
> On 11/23/21 10:59 AM, Greg KH wrote:
> > 
> > On Tue, Nov 23, 2021 at 10:45:06AM -0800, Lizhi Hou wrote:
> > > Fix the uartlite probe failure when it is mapped to address above 4G.
> > Fix it how?
> 
> Does this detail comment look ok to you?
> 
> The base address of uartlite registers could be 64 bit address which is from
> device resource. When ulite_probe() calls ulite_assign(), this 64 bit
> address is casted to 32-bit. The fix is to replace "u32" type with
> "phys_addr_t" type for the base address in ulite_assign() argument list.

Much better.

> > 
> > > Signed-off-by: Lizhi Hou <lizhi.hou@xilinx.com>
> > What commit caused this problem?  What commit does this fix?  Should it
> > go to stable kernels?
> 
> I searched the history. This problem was introduced by https://github.com/torvalds/linux/commit/8fa7b6100693e0b648ffd34564f6f41226502a19
> 
> And yes, I agree this should go to stable kernels. I will add
> stable@vger.kernel.org to cc list.

Thank you, please add a Fixes: tag to the patch as well when you
resubmit it.

greg k-h