[PATCH AUTOSEL 4.19 092/191] media: imx: work around false-positive warning, again

[PATCH AUTOSEL 4.19 092/191] media: imx: work around false-positive warning, again

[Sasha Levin]

From: Arnd Bergmann <arnd@arndb.de>

[ Upstream commit 8d1a4817cce1b15b4909f0e324a4f5af5952da67 ]

A warning that I thought to be solved by a previous patch of mine
has resurfaced with gcc-8:

media/imx/imx-media-csi.c: In function 'csi_link_validate':
media/imx/imx-media-csi.c:1025:20: error: 'upstream_ep' may be used uninitialized in this function [-Werror=maybe-uninitialized]
media/imx/imx-media-csi.c:1026:24: error: 'upstream_ep.bus_type' may be used uninitialized in this function [-Werror=maybe-uninitialized]
media/imx/imx-media-csi.c:127:19: error: 'upstream_ep.bus.parallel.bus_width' may be used uninitialized in this function [-Werror=maybe-uninitialized]
media/imx/imx-media-csi.c: In function 'csi_enum_mbus_code':
media/imx/imx-media-csi.c:132:9: error: '*((void *)&upstream_ep+12)' may be used uninitialized in this function [-Werror=maybe-uninitialized]
media/imx/imx-media-csi.c:132:48: error: 'upstream_ep.bus.parallel.bus_width' may be used uninitialized in this function [-Werror=maybe-uninitialized]

I spent some more time digging in this time, and think I have a better
fix, bailing out of the function that either initializes or errors
out here, which simplifies the code enough for gcc to figure out
what is going on. The earlier partial workaround can be removed now,
as the new workaround is better.

Fixes: 890f27693f2a ("media: imx: work around false-positive warning")

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/staging/media/imx/imx-media-csi.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
index d17ce1fb4ef51..0f8fdc347091b 100644
--- a/drivers/staging/media/imx/imx-media-csi.c
+++ b/drivers/staging/media/imx/imx-media-csi.c
@@ -166,6 +166,9 @@ static int csi_get_upstream_endpoint(struct csi_priv *priv,
 	struct v4l2_subdev *sd;
 	struct media_pad *pad;
 
+	if (!IS_ENABLED(CONFIG_OF))
+		return -ENXIO;
+
 	if (!priv->src_sd)
 		return -EPIPE;
 
@@ -1072,7 +1075,7 @@ static int csi_link_validate(struct v4l2_subdev *sd,
 			     struct v4l2_subdev_format *sink_fmt)
 {
 	struct csi_priv *priv = v4l2_get_subdevdata(sd);
-	struct v4l2_fwnode_endpoint upstream_ep = {};
+	struct v4l2_fwnode_endpoint upstream_ep;
 	bool is_csi2;
 	int ret;
 
-- 
2.20.1

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[PATCH AUTOSEL 4.19 156/191] x86/hyperv: Suppress "PCI: Fatal: No config space access function found"

[Sasha Levin]

From: Dexuan Cui <decui@microsoft.com>

[ Upstream commit 2f285f46240d67060061d153786740d4df53cd78 ]

A Generation-2 Linux VM on Hyper-V doesn't have the legacy PCI bus, and
users always see the scary warning, which is actually harmless.

Suppress it.

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: KY Srinivasan <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: "devel@linuxdriverproject.org" <devel@linuxdriverproject.org>
Cc: Olaf Aepfle <olaf@aepfle.de>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Marcelo Cerri <marcelo.cerri@canonical.com>
Cc: Josh Poulson <jopoulso@microsoft.com>
Link: https://lkml.kernel.org/r/ <KU1P153MB0166D977DC930996C4BF538ABF1D0@KU1P153MB0166.APCP153.PROD.OUTLOOK.COM
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/x86/hyperv/hv_init.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index 3fb8551552862..8a9cff1f129dc 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -17,6 +17,7 @@
  *
  */
 
+#include <linux/efi.h>
 #include <linux/types.h>
 #include <asm/apic.h>
 #include <asm/desc.h>
@@ -257,6 +258,22 @@ static int hv_cpu_die(unsigned int cpu)
 	return 0;
 }
 
+static int __init hv_pci_init(void)
+{
+	int gen2vm = efi_enabled(EFI_BOOT);
+
+	/*
+	 * For Generation-2 VM, we exit from pci_arch_init() by returning 0.
+	 * The purpose is to suppress the harmless warning:
+	 * "PCI: Fatal: No config space access function found"
+	 */
+	if (gen2vm)
+		return 0;
+
+	/* For Generation-1 VM, we'll proceed in pci_arch_init().  */
+	return 1;
+}
+
 /*
  * This function is to be invoked early in the boot sequence after the
  * hypervisor has been detected.
@@ -333,6 +350,8 @@ void __init hyperv_init(void)
 
 	hv_apic_init();
 
+	x86_init.pci.arch_init = hv_pci_init;
+
 	/*
 	 * Register Hyper-V specific clocksource.
 	 */
-- 
2.20.1

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