Re: [BUG] 2.6.24-git usb reset problems

[Jens Axboe <jens.axboe-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>]

On Wed, Jan 30 2008, Geert Uytterhoeven wrote:
> On Tue, 29 Jan 2008, Jens Axboe wrote:
> > On Tue, Jan 29 2008, Jens Axboe wrote:
> > > On Tue, Jan 29 2008, James Bottomley wrote:
> > > > On Tue, 2008-01-29 at 11:10 -0800, Matthew Dharm wrote:
> > > > > For some reason, usb_sg_init is boned during auto-sense.
> > > > 
> > > > OK, that's implicating the scsi_eh_prep_cmnd() in the auto sense
> > > > code ... that was also an update in 2.6.24
> > > 
> > > yeah, already found the bug - it's assuming ->request_buffer holds the
> > > sglist, oops. Preparing a fix.
> > 
> > ok here goes, this saves and restores the sg table correctly. it also
> > fixes the usb bug for me.
> 
> I can confirm this patch fixes the errors I was seeing with current
> linux-2.6.git for the USB memory card readers in a Dell TFT connected
> to a PS3.

James, we need a fix for this pushed asap. So either we should merge the
below now, or push the bidi patchset that also fixes this. It all
depends on when you want to merge the bidi patches...

> > diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
> > index 547e85a..12770ef 100644
> > --- a/drivers/scsi/scsi_error.c
> > +++ b/drivers/scsi/scsi_error.c
> > @@ -622,13 +622,15 @@ void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,
> >  	ses->use_sg = scmd->use_sg;
> >  	ses->resid = scmd->resid;
> >  	ses->result = scmd->result;
> > +	memcpy(&ses->sense_sgl, &scmd->sg_table, sizeof(ses->sense_sgl));
> >  
> >  	if (sense_bytes) {
> >  		scmd->request_bufflen = min_t(unsigned,
> >  		                       SCSI_SENSE_BUFFERSIZE, sense_bytes);
> >  		sg_init_one(&ses->sense_sgl, scmd->sense_buffer,
> >  		                                       scmd->request_bufflen);
> > -		scmd->request_buffer = &ses->sense_sgl;
> > +		scmd->sg_table.sgl = &ses->sense_sgl;
> > +		scmd->sg_table.nents = scmd->sg_table.orig_nents = 1;
> >  		scmd->sc_data_direction = DMA_FROM_DEVICE;
> >  		scmd->use_sg = 1;
> >  		memset(scmd->cmnd, 0, sizeof(scmd->cmnd));
> > @@ -679,6 +681,7 @@ void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses)
> >  	scmd->request_bufflen = ses->bufflen;
> >  	scmd->request_buffer = ses->buffer;
> >  	scmd->use_sg = ses->use_sg;
> > +	memcpy(&scmd->sg_table, &ses->sg_table, sizeof(scmd->sg_table));
> >  	scmd->resid = ses->resid;
> >  	scmd->result = ses->result;
> >  }
> > diff --git a/include/scsi/scsi_eh.h b/include/scsi/scsi_eh.h
> > index d21b891..d43dc83 100644
> > --- a/include/scsi/scsi_eh.h
> > +++ b/include/scsi/scsi_eh.h
> > @@ -75,6 +75,7 @@ struct scsi_eh_save {
> >  
> >  	void *buffer;
> >  	unsigned bufflen;
> > +	struct sg_table sg_table;
> >  	unsigned short use_sg;
> >  	int resid;
> >  

-- 
Jens Axboe