Re: [PATCH v3 02/16] scsi: don't use fc_bsg_job::request and fc_bsg_job::reply directly

[Johannes Thumshirn]

On Tue, Nov 15, 2016 at 04:39:33PM +0100, Johannes Thumshirn wrote:
> On Tue, Nov 15, 2016 at 03:31:27PM +0100, Steffen Maier wrote:
> > Hi Johannes,
> > 
> > On 11/15/2016 12:56 PM, Johannes Thumshirn wrote:
> > > On Tue, Oct 25, 2016 at 09:43:14AM +0200, Johannes Thumshirn wrote:
> > > > On Fri, Oct 14, 2016 at 09:38:21AM +0200, Johannes Thumshirn wrote:
> > > > > On Thu, Oct 13, 2016 at 05:55:11PM +0200, Steffen Maier wrote:
> > > > > > Hm, still behaves for me like I reported for v2:
> > > > > > http://marc.info/?l=linux-scsi&m=147637177902937&w=2
> > > 
> > > [...]
> > > 
> > > > > 
> > > > > The rational behind this is, in fc_req_to_bsgjob() we're assigning
> > > > > job->request as req->cmd and job->request_len = req->cmd_len. But without
> > > > > checkinf job->request_len we don't know whether we're save to touch
> > > > > job->request (a.k.a. bsg_request).
> > > > 
> > > > Hi Steffen,
> > > > Did you have any chance testing this? I hacked fcping to work with non-FCoE
> > > > and rports as well and tested with FCoE and lpfc. No problems seen from my
> > > > side. I've also pused the series (With this change folded in) to my git
> > > > tree at [1] if this helps you in any way.
> > > > 
> > > > [1] https://git.kernel.org/cgit/linux/kernel/git/jth/linux.git/log/?h=scsi-bsg-rewrite-v4
> > > > 
> > > 
> > > So I finally have a test system up and running. I have good and bad news. The
> > > good news is, I can't get the system crashing with my patches, the bad news is
> > > I can't get zfcp_ping and zfcp_show to output something but HBA_STATUS_ERROR
> > > with my patches and without.
> 
> Please ignore my last mails, apparently it's a wise idea to check which user
> id one has before running zfcp_ping...
> 
> The good news for this is, I can now recreate the crashes you have and thus
> have a chance to fix them :-)

So JFTR, I was able to fix the 1 problem introduced by this patch, it's the
follwoing hunk:
@@ -3726,9 +3729,9 @@ fc_req_to_bsgjob(struct Scsi_Host *shost, struct fc_rport *rport,
        if (i->f->dd_bsg_size)
                job->dd_data = (void *)&job[1];
        spin_lock_init(&job->job_lock);
-       job->request = (struct fc_bsg_request *)req->cmd;
+       bsg_request = (struct fc_bsg_request *)req->cmd;
        job->request_len = req->cmd_len;
-       job->reply = req->sense;
+       bsg_reply = req->sense;
        job->reply_len = SCSI_SENSE_BUFFERSIZE; /* Size of sense buffer
                                                 * allocated */
        if (req->bio) {

But as fc_req_to_bsgjob() get's deleted in Patch 15/16 the problem is
re-introduced. Unfortunately the fix isn't as trivial as for 2/16 so I'm still
trying to nail it down.

Thanks,
	Johannes

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