Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1740191

Re: [PATCH] ACPI / PCI: Bail early in acpi_pci_add_bus() if there is no ACPI handle

Show all headers | View raw

On Thu, Sep 14, 2017 at 04:50:14PM +0200, Vitaly Kuznetsov wrote:
> Hyper-V instances support PCI pass-through which is implemented through
> PV pci-hyperv driver. When a device is passed through a new root PCI bus
> is created in the guest. The bus sits on top of VMBus and has no
> associated information in ACPI. acpi_pci_add_bus() in this case proceeds
> all the way to acpi_evaluate_dsm() with reports
> 
>     ACPI: \: failed to evaluate _DSM (0x1001)
> 
> While acpi_pci_slot_enumerate() and acpiphp_enumerate_slots() are protected
> against ACPI_HANDLE() being NULL and do nothing acpi_evaluate_dsm() is not
> and gives us the error. It seems the correct fix is to not do anything in
> acpi_pci_add_bus() in such cases.
> 
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>

Applied to pci/acpi for v4.15, thanks!

Rafael, let me know if you have any objections or if you'd rather take
it yourself.

> ---
>  drivers/pci/pci-acpi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
> index a8da543b3814..4708eb9df71b 100644
> --- a/drivers/pci/pci-acpi.c
> +++ b/drivers/pci/pci-acpi.c
> @@ -624,7 +624,7 @@ void acpi_pci_add_bus(struct pci_bus *bus)
>  	union acpi_object *obj;
>  	struct pci_host_bridge *bridge;
>  
> -	if (acpi_pci_disabled || !bus->bridge)
> +	if (acpi_pci_disabled || !bus->bridge || !ACPI_HANDLE(bus->bridge))
>  		return;
>  
>  	acpi_pci_slot_enumerate(bus);
> -- 
> 2.13.5
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH] ACPI / PCI: Bail early in acpi_pci_add_bus() if there is no ACPI handle Vitaly Kuznetsov <vkuznets@redhat.com> - 2017-09-14 17:00 +0200
  Re: [PATCH] ACPI / PCI: Bail early in acpi_pci_add_bus() if there is  no ACPI handle Bjorn Helgaas <helgaas@kernel.org> - 2017-09-26 22:30 +0200
    Re: [PATCH] ACPI / PCI: Bail early in acpi_pci_add_bus() if there is no ACPI handle "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2017-09-26 22:40 +0200

csiph-web