skd: Fix incomplete cleanup of MSI-X interrupt

When enabling MSI-X interrupts fails due to lack of memory
the call to pci_disable_msix() is missed and the device is
left with MSI-X interrupts enabled while the driver assumes
otherwise. This update fixes the described misbehaviour and
cleans up the code of skd_release_msix() function.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: linux-pci@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 26 insertions, 24 deletions

diff --git a/drivers/block/skd_main.c b/drivers/block/skd_main.c
index 3fa0918ddaf8..d0550ba948fa 100644
--- a/drivers/block/skd_main.c
+++ b/drivers/block/skd_main.c
@@ -3910,43 +3910,44 @@ static void skd_release_msix(struct skd_device *skdev)
         struct skd_msix_entry *qentry;
         int i;
 
-        if (skdev->msix_entries == NULL)
-                return;
-        for (i = 0; i < skdev->msix_count; i++) {
-                qentry = &skdev->msix_entries[i];
-                skdev = qentry->rsp;
+        if (skdev->msix_entries) {
+                for (i = 0; i < skdev->msix_count; i++) {
+                        qentry = &skdev->msix_entries[i];
+                        skdev = qentry->rsp;
+
+                        if (qentry->have_irq)
+                                devm_free_irq(&skdev->pdev->dev,
+                                              qentry->vector, qentry->rsp);
+                }
 
-                if (qentry->have_irq)
-                        devm_free_irq(&skdev->pdev->dev,
-                                      qentry->vector, qentry->rsp);
+                kfree(skdev->msix_entries);
         }
-        pci_disable_msix(skdev->pdev);
-        kfree(skdev->msix_entries);
+
+        if (skdev->msix_count)
+                pci_disable_msix(skdev->pdev);
+
         skdev->msix_count = 0;
         skdev->msix_entries = NULL;
 }
 
 static int skd_acquire_msix(struct skd_device *skdev)
 {
-        int i, rc;
-        struct pci_dev *pdev;
-        struct msix_entry *entries = NULL;
+        int i, rc, msix_count = SKD_MAX_MSIX_COUNT;
+        struct pci_dev *pdev = skdev->pdev;
+        struct msix_entry *entries;
         struct skd_msix_entry *qentry;
 
-        pdev = skdev->pdev;
-        skdev->msix_count = SKD_MAX_MSIX_COUNT;
-        entries = kzalloc(sizeof(struct msix_entry) * SKD_MAX_MSIX_COUNT,
-                          GFP_KERNEL);
+        entries = kzalloc(sizeof(struct msix_entry) * msix_count, GFP_KERNEL);
         if (!entries)
                 return -ENOMEM;
 
-        for (i = 0; i < SKD_MAX_MSIX_COUNT; i++)
+        for (i = 0; i < msix_count; i++)
                 entries[i].entry = i;
 
-        rc = pci_enable_msix(pdev, entries, SKD_MAX_MSIX_COUNT);
+        rc = pci_enable_msix(pdev, entries, msix_count);
         if (rc < 0)
                 goto msix_out;
-        if (rc) {
+        else if (rc) {
                 if (rc < SKD_MIN_MSIX_COUNT) {
                         pr_err("(%s): failed to enable MSI-X %d\n",
                                skd_name(skdev), rc);
@@ -3956,20 +3957,21 @@ static int skd_acquire_msix(struct skd_device *skdev)
                          skdev->name, __func__, __LINE__,
                          pci_name(pdev), skdev->name, rc);
 
-                skdev->msix_count = rc;
-                rc = pci_enable_msix(pdev, entries, skdev->msix_count);
+                msix_count = rc;
+                rc = pci_enable_msix(pdev, entries, msix_count);
                 if (rc) {
                         pr_err("(%s): failed to enable MSI-X "
                                "support (%d) %d\n",
-                               skd_name(skdev), skdev->msix_count, rc);
+                               skd_name(skdev), msix_count, rc);
                         goto msix_out;
                 }
         }
+
+        skdev->msix_count = msix_count;
         skdev->msix_entries = kzalloc(sizeof(struct skd_msix_entry) *
                                       skdev->msix_count, GFP_KERNEL);
         if (!skdev->msix_entries) {
                 rc = -ENOMEM;
-                skdev->msix_count = 0;
                 pr_err("(%s): msix table allocation error\n",
                        skd_name(skdev));
                 goto msix_out;