DriverDev-Devel Archive on lore.kernel.org
 help / color / Atom feed
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Josh Poulson <jopoulso@microsoft.com>,
	Sasha Levin <sashal@kernel.org>, Olaf Aepfle <olaf@aepfle.de>,
	Stephen Hemminger <sthemmin@microsoft.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Haiyang Zhang <haiyangz@microsoft.com>,
	stable@vger.kernel.org, Michael Kelley <mikelley@microsoft.com>,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	Marcelo Cerri <marcelo.cerri@canonical.com>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Andy Whitcroft <apw@canonical.com>,
	"devel@linuxdriverproject.org" <devel@linuxdriverproject.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Jason Wang <jasowang@redhat.com>
Subject: [PATCH 4.14 214/239] x86/hyperv: Suppress "PCI: Fatal: No config space access function found"
Date: Tue, 19 Nov 2019 06:20:14 +0100
Message-ID: <20191119051338.898151241@linuxfoundation.org> (raw)
In-Reply-To: <20191119051255.850204959@linuxfoundation.org>

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 2e9d58cc371e6..2653b7b25d176 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/hypervisor.h>
 #include <asm/hyperv.h>
@@ -101,6 +102,22 @@ static int hv_cpu_init(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.
@@ -154,6 +171,8 @@ void hyperv_init(void)
 
 	hyper_alloc_mmu();
 
+	x86_init.pci.arch_init = hv_pci_init;
+
 	/*
 	 * Register Hyper-V specific clocksource.
 	 */
-- 
2.20.1



_______________________________________________
devel mailing list
devel@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

           reply index

Thread overview: expand[flat|nested]  mbox.gz  Atom feed
 [parent not found: <20191119051255.850204959@linuxfoundation.org>]

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20191119051338.898151241@linuxfoundation.org \
    --to=gregkh@linuxfoundation.org \
    --cc=apw@canonical.com \
    --cc=devel@linuxdriverproject.org \
    --cc=haiyangz@microsoft.com \
    --cc=hpa@zytor.com \
    --cc=jasowang@redhat.com \
    --cc=jopoulso@microsoft.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=marcelo.cerri@canonical.com \
    --cc=mikelley@microsoft.com \
    --cc=olaf@aepfle.de \
    --cc=sashal@kernel.org \
    --cc=stable@vger.kernel.org \
    --cc=sthemmin@microsoft.com \
    --cc=tglx@linutronix.de \
    --cc=vkuznets@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

DriverDev-Devel Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/driverdev-devel/0 driverdev-devel/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 driverdev-devel driverdev-devel/ https://lore.kernel.org/driverdev-devel \
		driverdev-devel@linuxdriverproject.org devel@driverdev.osuosl.org
	public-inbox-index driverdev-devel

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.linuxdriverproject.driverdev-devel


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git