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Bottomley" , "Martin K. Petersen" , clang-built-linux@googlegroups.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org Subject: Re: [PATCH] scsi: ibmvscsi: Don't use rc uninitialized in ibmvscsi_do_work Message-ID: <20190603032344.GA26021@archlinux-epyc> References: <20190531185306.41290-1-natechancellor@gmail.com> <87blzgnvhx.fsf@concordia.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87blzgnvhx.fsf@concordia.ellerman.id.au> User-Agent: Mutt/1.12.0 (2019-05-25) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Michael, On Sun, Jun 02, 2019 at 08:15:38PM +1000, Michael Ellerman wrote: > Hi Nathan, > > It's always preferable IMHO to keep any initialisation as localised as > possible, so that the compiler can continue to warn about uninitialised > usages elsewhere. In this case that would mean doing the rc = 0 in the > switch, something like: I am certainly okay with implementing this in a v2. I mulled over which would be preferred, I suppose I guessed wrong :) Thank you for the review and input. > > diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c > index 727c31dc11a0..7ee5755cf636 100644 > --- a/drivers/scsi/ibmvscsi/ibmvscsi.c > +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c > @@ -2123,9 +2123,6 @@ static void ibmvscsi_do_work(struct ibmvscsi_host_data *hostdata) > > spin_lock_irqsave(hostdata->host->host_lock, flags); > switch (hostdata->action) { > - case IBMVSCSI_HOST_ACTION_NONE: > - case IBMVSCSI_HOST_ACTION_UNBLOCK: > - break; > case IBMVSCSI_HOST_ACTION_RESET: > spin_unlock_irqrestore(hostdata->host->host_lock, flags); > rc = ibmvscsi_reset_crq_queue(&hostdata->queue, hostdata); > @@ -2142,7 +2139,10 @@ static void ibmvscsi_do_work(struct ibmvscsi_host_data *hostdata) > if (!rc) > rc = ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0); > break; > + case IBMVSCSI_HOST_ACTION_NONE: > + case IBMVSCSI_HOST_ACTION_UNBLOCK: > default: > + rc = 0; > break; > } > > > But then that makes me wonder if that's actually correct? > > If we get an action that we don't recognise should we just throw it away > like that? (by doing hostdata->action = IBMVSCSI_HOST_ACTION_NONE). Tyrel? However, because of this, I will hold off on v2 until Tyrel can give some feedback. Thanks, Nathan