Re: reeze while write on external usb 3.0 hard disk [Bug 204095]

From: Piergiorgio Sartor <piergiorgio.sartor@nexgo.de>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: Piergiorgio Sartor <piergiorgio.sartor@nexgo.de>,
	Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	USB list <linux-usb@vger.kernel.org>,
	linux-block@vger.kernel.org,
	Kernel development list <linux-kernel@vger.kernel.org>
Subject: Re: reeze while write on external usb 3.0 hard disk [Bug 204095]
Date: Sat, 9 Nov 2019 00:05:36 +0100	[thread overview]
Message-ID: <20191108230536.GA11931@lazy.lzy> (raw)
In-Reply-To: <Pine.LNX.4.44L0.1910171522200.18407-100000@netrider.rowland.org>

On Thu, Oct 17, 2019 at 03:23:34PM -0400, Alan Stern wrote:
> On Thu, 17 Oct 2019, Piergiorgio Sartor wrote:
> 
> > > Here is one more thing you can try.  I have no idea whether it will 
> > > make any difference, but the Changelog entry for the patch you 
> > > identified suggests that it might help.
> > > 
> > > Alan Stern
> > > 
> > > 
> > > 
> > > Index: usb-devel/drivers/usb/storage/scsiglue.c
> > > ===================================================================
> > > --- usb-devel.orig/drivers/usb/storage/scsiglue.c
> > > +++ usb-devel/drivers/usb/storage/scsiglue.c
> > > @@ -68,7 +68,6 @@ static const char* host_info(struct Scsi
> > >  static int slave_alloc (struct scsi_device *sdev)
> > >  {
> > >  	struct us_data *us = host_to_us(sdev->host);
> > > -	int maxp;
> > >  
> > >  	/*
> > >  	 * Set the INQUIRY transfer length to 36.  We don't use any of
> > > @@ -78,15 +77,6 @@ static int slave_alloc (struct scsi_devi
> > >  	sdev->inquiry_len = 36;
> > >  
> > >  	/*
> > > -	 * USB has unusual scatter-gather requirements: the length of each
> > > -	 * scatterlist element except the last must be divisible by the
> > > -	 * Bulk maxpacket value.  Fortunately this value is always a
> > > -	 * power of 2.  Inform the block layer about this requirement.
> > > -	 */
> > > -	maxp = usb_maxpacket(us->pusb_dev, us->recv_bulk_pipe, 0);
> > > -	blk_queue_virt_boundary(sdev->request_queue, maxp - 1);
> > > -
> > > -	/*
> > >  	 * Some host controllers may have alignment requirements.
> > >  	 * We'll play it safe by requiring 512-byte alignment always.
> > >  	 */
> > 
> > Hi,
> > 
> > I tested the patch.
> > 
> > Assumming I did everything properly, add patch,
> > test, issue not showing up, remove patch, re-test,
> > issue present.
> > 
> > It seems this patch you provide solves the issue.
> > 
> > Thanks a lot for the support and the solution.
> > 
> > I guess now this patch will be integrated into
> > mainline sometimes.
> > Please let me know, in this thread or directly, in
> > which kernel it will be available.
> 
> I'm busy for the next few days, but I will submit the patch next week.

Hi again,

this message to let you know I tested
kernel 5.3.9 (always from Fedora), to
which Greg Kroah-Hartman added your
patch, and everything seems to work
fine, no problems detected so far.

Thanks,

bye,

-- 

piergiorgio