From: Arnd Bergmann <arnd@arndb.de>
To: Jens Axboe <axboe@fb.com>
Cc: Christoph Hellwig <hch@lst.de>, Arnd Bergmann <arnd@arndb.de>,
        Mike Christie <mchristi@redhat.com>, Hannes Reinecke <hare@suse.com>,
        Ming Lin <ming.l@ssi.samsung.com>, linux-kernel@vger.kernel.org
Subject: [PATCH 1/2] skd: fix msix error handling
Date: Wed,  9 Nov 2016 13:55:34 +0100
Message-Id: <20161109125555.1440353-1-arnd@arndb.de>
MIME-Version: 1.0
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Sender: linux-kernel-owner@vger.kernel.org
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Lines: 49

As reported by gcc -Wmaybe-uninitialized, the cleanup path for
skd_acquire_msix tries to free the already allocated msi-x vectors
in reverse order, but the index variable may not have been
used yet:

drivers/block/skd_main.c: In function ‘skd_acquire_irq’:
drivers/block/skd_main.c:3890:8: error: ‘i’ may be used uninitialized in this function [-Werror=maybe-uninitialized]

This changes the failure path to skip releasing the interrupts
if we have not started requesting them yet.

Fixes: 180b0ae77d49 ("skd: use pci_alloc_irq_vectors")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/block/skd_main.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/block/skd_main.c b/drivers/block/skd_main.c
index a58256cd94d7..66146b349229 100644
--- a/drivers/block/skd_main.c
+++ b/drivers/block/skd_main.c
@@ -3849,7 +3849,7 @@ static int skd_acquire_msix(struct skd_device *skdev)
 	if (rc < 0) {
 		pr_err("(%s): failed to enable MSI-X %d\n",
 		       skd_name(skdev), rc);
-		goto msix_out;
+		goto out;
 	}
 
 	skdev->msix_entries = kcalloc(SKD_MAX_MSIX_COUNT,
@@ -3858,7 +3858,7 @@ static int skd_acquire_msix(struct skd_device *skdev)
 		rc = -ENOMEM;
 		pr_err("(%s): msix table allocation error\n",
 		       skd_name(skdev));
-		goto msix_out;
+		goto out;
 	}
 
 	/* Enable MSI-X vectors for the base queue */
@@ -3889,6 +3889,7 @@ static int skd_acquire_msix(struct skd_device *skdev)
 msix_out:
 	while (--i >= 0)
 		devm_free_irq(&pdev->dev, pci_irq_vector(pdev, i), skdev);
+out:
 	kfree(skdev->msix_entries);
 	skdev->msix_entries = NULL;
 	return rc;
-- 
2.9.0