Boaz Harrosh wrote: > On Thu, Nov 15 2007 at 19:15 +0200, Matthew Dharm <mdharm-kernel@xxxxxxxxxxxxxxxxxx> wrote: >> On Wed, Nov 14, 2007 at 10:23:09AM +0100, Gabriel C wrote: >>> Matthew Dharm wrote: >>>> On Wed, Nov 14, 2007 at 06:33:39AM +0100, Gabriel C wrote: >>>>> Matthew Dharm wrote: >>>>>> On Tue, Nov 13, 2007 at 07:49:24PM -0800, Greg KH wrote: >>>>>>> Matt, are these the errors you were worried about with the patch we were >>>>>>> just talking about tha tis in my tree? >>>>>> I can't tell from these logs. >>>>> There is the dmesg with CONFIG_USB_STORAGE_DEBUG : >>>>> >>>>> http://194.231.229.228/dmesg-2.6.24-rc2-mm1 >>>> Good news: This isn't the bug Greg was worried about. >>>> >>>> Bad news: Something is seriously strange here. Note the following from the >>>> logs: >>>> >>>> Nov 14 06:07:43 lara [ 41.890614] usb-storage: Bulk Status S 0x53425355 T 0xd R 0 Stat 0x0 >>>> Nov 14 06:07:43 lara [ 41.890616] usb-storage: -- unexpectedly short transfer >>>> >>>> Note the 'R' value of zero -- this is the residue value. It indicates a >>>> complete transfer, and that matches the log lines immediately previous >>>> which indicate a 4K transfer which completed properly. >>>> >>>> If residue is zero, then srb->resid should be zero. Take a look in >>>> linux/usb/storage/transport.c in usb_stor_Bulk_transport() >>>> >>>> If srb->resid is zero, then you should NEVER get the "unexpectedly short >>>> transfer" message. Look at usb_stor_invoke_transport() in the same file. >>> That code got replaced recently but I have no idea about it. >>> >>> ( http://git.kernel.org/?p=linux/kernel/git/jejb/scsi-misc-2.6.git;a=shortlog see the patches from Boaz Harrosh) >>> >>> srb->resid got replaced by scsi_get_resid() it I see that right. >>> >>> I'm CC'ing the author , he will know I think. >> The replacement looks, to my eye, to be logically correct. The patch was >> pretty clean. >> >> Then again, I haven't looked at what is "under the hood" of the accessor >> functions. Perhaps there is a side-effect somewhere in there? >> >> Perhaps a quick debugging test -- print the value of scsi_get_resid(srb) >> just after it's initialized to zero at the top of >> usb_stor_invoke_transport(), and then just after the call to >> us->transport(). >> > > I have found the bug. My bad sorry about that. Patch below > It is because I switched from use of usb_stor_bulk_transfer_sg() > to usb_stor_bulk_transfer_sglist, but forgot the residual handling. Your patch fixes the problem. Thx. > > (Please send scsi bugs to scsi list. My lkml mental filters are > much higher, Sorry for not seeing this yesterday) Uhh sorry I forgot to CC linux-scsi =) > > ---- > From: Boaz Harrosh <bharrosh@xxxxxxxxxxx> > Date: Thu, 15 Nov 2007 20:07:56 +0200 > Subject: [PATCH] Fix bug in last usb accessor patch > >>>> Bad news: Something is seriously strange here. Note the following from the >>>> logs: >>>> >>>> Nov 14 06:07:43 lara [ 41.890614] usb-storage: Bulk Status S 0x53425355 T 0xd R 0 Stat 0x0 >>>> Nov 14 06:07:43 lara [ 41.890616] usb-storage: -- unexpectedly short transfer >>>> >>>> Note the 'R' value of zero -- this is the residue value. It indicates a >>>> complete transfer, and that matches the log lines immediately previous >>>> which indicate a 4K transfer which completed properly. >>>> >>>> If residue is zero, then srb->resid should be zero. Take a look in >>>> linux/usb/storage/transport.c in usb_stor_Bulk_transport() >>>> >>>> If srb->resid is zero, then you should NEVER get the "unexpectedly short >>>> transfer" message. Look at usb_stor_invoke_transport() in the same file. >>> That code got replaced recently but I have no idea about it. > > wrong resid handling fixed > > Signed-off-by: Boaz Harrosh <bharrosh@xxxxxxxxxxx> > --- > drivers/usb/storage/transport.c | 7 ++++--- > 1 files changed, 4 insertions(+), 3 deletions(-) > > diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c > index d3a84a2..d9f4912 100644 > --- a/drivers/usb/storage/transport.c > +++ b/drivers/usb/storage/transport.c > @@ -465,11 +465,12 @@ static int usb_stor_bulk_transfer_sglist(struct us_data *us, unsigned int pipe, > int usb_stor_bulk_srb(struct us_data* us, unsigned int pipe, > struct scsi_cmnd* srb) > { > - int resid = scsi_get_resid(srb); > + unsigned int partial; > int result = usb_stor_bulk_transfer_sglist(us, pipe, scsi_sglist(srb), > scsi_sg_count(srb), scsi_bufflen(srb), > - &resid); > - scsi_set_resid(srb, resid); > + &partial); > + > + scsi_set_resid(srb, scsi_bufflen(srb) - partial); > return result; > } > - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
