[dpdk-stable] patch 'igb_uio: fix build on Linux 5.3 for fall through' has been queued to LTS release 18.11.3

[Kevin Traynor]

Hi,

FYI, your patch has been queued to LTS release 18.11.3

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 09/12/19. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/kevintraynor/dpdk-stable-queue

This queued commit can be viewed at:
https://github.com/kevintraynor/dpdk-stable-queue/commit/b081b185c07da807661d62c1b20653012b8d7e3c

Thanks.

Kevin Traynor

---
>From b081b185c07da807661d62c1b20653012b8d7e3c Mon Sep 17 00:00:00 2001
From: Ferruh Yigit <ferruh.yigit at intel.com>
Date: Mon, 29 Jul 2019 13:32:16 +0100
Subject: [PATCH] igb_uio: fix build on Linux 5.3 for fall through
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

[ upstream commit c96bbbd010f7abb88c2ca2ed9dfc5ecd37e9027d ]

build error:
kernel/linux/igb_uio/igb_uio.c:
   In function ‘igbuio_pci_enable_interrupts’:
   kernel/linux/igb_uio/igb_uio.c:230:6:
   error: this statement may fall through
   [-Werror=implicit-fallthrough=]
  230 |   if (pci_alloc_irq_vectors(udev->pdev, 1, 1, ....
kernel/linux/igb_uio/igb_uio.c:240:2: note: here
  240 |  case RTE_INTR_MODE_MSI:
      |  ^~~~

The build error is caused by Linux kernel commit in 5.3 that enables the
"-Wimplicit-fallthrough=3" gcc flag.
Commit a035d552a93b ("Makefile: Globally enable fall-through warning")

To fix the error, either a gcc attribute can be provided [1] or a code
comment with some defined syntax need to be provided [2], since there is
already comments, updated them slightly to match the required syntax to
fix the build error.

[1]
"__attribute__ ((fallthrough));"

[2]
[ \t.!]*([Ee]lse,? |[Ii]ntentional(ly)? )?
fall(s | |-)?thr(ough|u)[ \t.!]*(-[^\n\r]*)?

Signed-off-by: Ferruh Yigit <ferruh.yigit at intel.com>
---
 kernel/linux/igb_uio/igb_uio.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/linux/igb_uio/igb_uio.c b/kernel/linux/igb_uio/igb_uio.c
index 3cf394bdf..039f5a5f6 100644
--- a/kernel/linux/igb_uio/igb_uio.c
+++ b/kernel/linux/igb_uio/igb_uio.c
@@ -237,5 +237,5 @@ igbuio_pci_enable_interrupts(struct rte_uio_pci_dev *udev)
 #endif
 
-	/* fall back to MSI */
+	/* falls through - to MSI */
 	case RTE_INTR_MODE_MSI:
 #ifndef HAVE_ALLOC_IRQ_VECTORS
@@ -256,5 +256,5 @@ igbuio_pci_enable_interrupts(struct rte_uio_pci_dev *udev)
 		}
 #endif
-	/* fall back to INTX */
+	/* falls through - to INTX */
 	case RTE_INTR_MODE_LEGACY:
 		if (pci_intx_mask_supported(udev->pdev)) {
@@ -266,5 +266,5 @@ igbuio_pci_enable_interrupts(struct rte_uio_pci_dev *udev)
 		}
 		dev_notice(&udev->pdev->dev, "PCI INTX mask not supported\n");
-	/* fall back to no IRQ */
+	/* falls through - to no IRQ */
 	case RTE_INTR_MODE_NONE:
 		udev->mode = RTE_INTR_MODE_NONE;
-- 
2.20.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2019-09-05 10:36:48.489815891 +0100
+++ 0016-igb_uio-fix-build-on-Linux-5.3-for-fall-through.patch	2019-09-05 10:36:47.493700929 +0100
@@ -1 +1 @@
-From c96bbbd010f7abb88c2ca2ed9dfc5ecd37e9027d Mon Sep 17 00:00:00 2001
+From b081b185c07da807661d62c1b20653012b8d7e3c Mon Sep 17 00:00:00 2001
@@ -8,0 +9,2 @@
+[ upstream commit c96bbbd010f7abb88c2ca2ed9dfc5ecd37e9027d ]
+
@@ -35,2 +36,0 @@
-
-Cc: stable at dpdk.org