From: Dexuan Cui <decui@xxxxxxxxxxxxx> [ 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@xxxxxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: KY Srinivasan <kys@xxxxxxxxxxxxx> Cc: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx> Cc: Stephen Hemminger <sthemmin@xxxxxxxxxxxxx> Cc: "devel@xxxxxxxxxxxxxxxxxxxxxx" <devel@xxxxxxxxxxxxxxxxxxxxxx> Cc: Olaf Aepfle <olaf@xxxxxxxxx> Cc: Andy Whitcroft <apw@xxxxxxxxxxxxx> Cc: Jason Wang <jasowang@xxxxxxxxxx> Cc: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> Cc: Marcelo Cerri <marcelo.cerri@xxxxxxxxxxxxx> Cc: Josh Poulson <jopoulso@xxxxxxxxxxxxx> Link: https://lkml.kernel.org/r/ <KU1P153MB0166D977DC930996C4BF538ABF1D0@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- 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
