From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nathan Chancellor Subject: [PATCH v3] scsi: ibmvscsi: Don't use rc uninitialized in ibmvscsi_do_work Date: Mon, 3 Jun 2019 16:44:06 -0700 Message-ID: <20190603234405.29600-1-natechancellor@gmail.com> References: <20190603221941.65432-1-natechancellor@gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190603221941.65432-1-natechancellor@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Tyrel Datwyler , "James E.J. Bottomley" , "Martin K. Petersen" Cc: linux-scsi@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Nathan Chancellor , Michael Ellerman List-Id: linux-scsi@vger.kernel.org clang warns: drivers/scsi/ibmvscsi/ibmvscsi.c:2126:7: warning: variable 'rc' is used uninitialized whenever switch case is taken [-Wsometimes-uninitialized] case IBMVSCSI_HOST_ACTION_NONE: ^~~~~~~~~~~~~~~~~~~~~~~~~ drivers/scsi/ibmvscsi/ibmvscsi.c:2151:6: note: uninitialized use occurs here if (rc) { ^~ Initialize rc in the IBMVSCSI_HOST_ACTION_UNBLOCK case statement then shuffle IBMVSCSI_HOST_ACTION_NONE down to the default case statement and make it return early so that rc is never used uninitialized in this function. Fixes: 035a3c4046b5 ("scsi: ibmvscsi: redo driver work thread to use enum action states") Link: https://github.com/ClangBuiltLinux/linux/issues/502 Suggested-by: Michael Ellerman Suggested-by: Tyrel Datwyler Signed-off-by: Nathan Chancellor --- v1 -> v2: * Initialize rc in the case statements, rather than at the top of the function, as suggested by Michael. v2 -> v3: * default and IBMVSCSI_HOST_ACTION_NONE now return early from the function, as requested by Tyrel. drivers/scsi/ibmvscsi/ibmvscsi.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c index 65053daef5f7..7f66a7783209 100644 --- a/drivers/scsi/ibmvscsi/ibmvscsi.c +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c @@ -2109,8 +2109,8 @@ 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: + rc = 0; break; case IBMVSCSI_HOST_ACTION_RESET: spin_unlock_irqrestore(hostdata->host->host_lock, flags); @@ -2128,8 +2128,10 @@ 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: default: - break; + spin_unlock_irqrestore(hostdata->host->host_lock, flags); + return; } hostdata->action = IBMVSCSI_HOST_ACTION_NONE; -- 2.22.0.rc3