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. */