2019-07-03 17:01:28

by Randy Dunlap

[permalink] [raw]
Subject: [PATCH v2] PCI: hv: fix pci-hyperv build when SYSFS not enabled

From: Randy Dunlap <[email protected]>

Fix build of drivers/pci/controller/pci-hyperv.o when
CONFIG_SYSFS is not set/enabled by adding stubs for
pci_create_slot() and pci_destroy_slot().

Fixes these build errors:

ERROR: "pci_destroy_slot" [drivers/pci/controller/pci-hyperv.ko] undefined!
ERROR: "pci_create_slot" [drivers/pci/controller/pci-hyperv.ko] undefined!

Fixes: a15f2c08c708 ("PCI: hv: support reporting serial number as slot information")

Signed-off-by: Randy Dunlap <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Jake Oshins <[email protected]>
Cc: "K. Y. Srinivasan" <[email protected]>
Cc: Haiyang Zhang <[email protected]>
Cc: Stephen Hemminger <[email protected]>
Cc: Sasha Levin <[email protected]>
Cc: Bjorn Helgaas <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: Dexuan Cui <[email protected]>
Cc: Yuehaibing <[email protected]>
---
v2:
- provide non-CONFIG_SYSFS stubs for pci_create_slot() and
pci_destroy_slot() [suggested by Matthew Wilcox <[email protected]>]
- use the correct Fixes: tag [Dexuan Cui <[email protected]>]

include/linux/pci.h | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)

--- lnx-52-rc7.orig/include/linux/pci.h
+++ lnx-52-rc7/include/linux/pci.h
@@ -25,6 +25,7 @@
#include <linux/ioport.h>
#include <linux/list.h>
#include <linux/compiler.h>
+#include <linux/err.h>
#include <linux/errno.h>
#include <linux/kobject.h>
#include <linux/atomic.h>
@@ -947,14 +948,21 @@ int pci_scan_root_bus_bridge(struct pci_
struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev,
int busnr);
void pcie_update_link_speed(struct pci_bus *bus, u16 link_status);
+#ifdef CONFIG_SYSFS
+void pci_dev_assign_slot(struct pci_dev *dev);
struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
const char *name,
struct hotplug_slot *hotplug);
void pci_destroy_slot(struct pci_slot *slot);
-#ifdef CONFIG_SYSFS
-void pci_dev_assign_slot(struct pci_dev *dev);
#else
static inline void pci_dev_assign_slot(struct pci_dev *dev) { }
+static inline struct pci_slot *pci_create_slot(struct pci_bus *parent,
+ int slot_nr,
+ const char *name,
+ struct hotplug_slot *hotplug) {
+ return ERR_PTR(-EINVAL);
+}
+static inline void pci_destroy_slot(struct pci_slot *slot) { }
#endif
int pci_scan_slot(struct pci_bus *bus, int devfn);
struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn);



2019-07-03 18:07:31

by Haiyang Zhang

[permalink] [raw]
Subject: RE: [PATCH v2] PCI: hv: fix pci-hyperv build when SYSFS not enabled



> -----Original Message-----
> From: Randy Dunlap <[email protected]>
> Sent: Wednesday, July 3, 2019 12:59 PM
> To: LKML <[email protected]>; linux-pci <linux-
> [email protected]>
> Cc: Matthew Wilcox <[email protected]>; Jake Oshins
> <[email protected]>; KY Srinivasan <[email protected]>; Haiyang
> Zhang <[email protected]>; Stephen Hemminger
> <[email protected]>; Sasha Levin <[email protected]>; Bjorn
> Helgaas <[email protected]>; [email protected]; Dexuan
> Cui <[email protected]>; Yuehaibing <[email protected]>
> Subject: [PATCH v2] PCI: hv: fix pci-hyperv build when SYSFS not enabled
>
> From: Randy Dunlap <[email protected]>
>
> Fix build of drivers/pci/controller/pci-hyperv.o when
> CONFIG_SYSFS is not set/enabled by adding stubs for
> pci_create_slot() and pci_destroy_slot().
>
> Fixes these build errors:
>
> ERROR: "pci_destroy_slot" [drivers/pci/controller/pci-hyperv.ko] undefined!
> ERROR: "pci_create_slot" [drivers/pci/controller/pci-hyperv.ko] undefined!
>
> Fixes: a15f2c08c708 ("PCI: hv: support reporting serial number as slot
> information")
>
> Signed-off-by: Randy Dunlap <[email protected]>
> Cc: Matthew Wilcox <[email protected]>
> Cc: Jake Oshins <[email protected]>
> Cc: "K. Y. Srinivasan" <[email protected]>
> Cc: Haiyang Zhang <[email protected]>
> Cc: Stephen Hemminger <[email protected]>
> Cc: Sasha Levin <[email protected]>
> Cc: Bjorn Helgaas <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: Dexuan Cui <[email protected]>
> Cc: Yuehaibing <[email protected]>
> ---
> v2:
> - provide non-CONFIG_SYSFS stubs for pci_create_slot() and
> pci_destroy_slot() [suggested by Matthew Wilcox <[email protected]>]
> - use the correct Fixes: tag [Dexuan Cui <[email protected]>]
>
> include/linux/pci.h | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> --- lnx-52-rc7.orig/include/linux/pci.h
> +++ lnx-52-rc7/include/linux/pci.h
> @@ -25,6 +25,7 @@
> #include <linux/ioport.h>
> #include <linux/list.h>
> #include <linux/compiler.h>
> +#include <linux/err.h>
> #include <linux/errno.h>
> #include <linux/kobject.h>
> #include <linux/atomic.h>
> @@ -947,14 +948,21 @@ int pci_scan_root_bus_bridge(struct pci_
> struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev
> *dev,
> int busnr);
> void pcie_update_link_speed(struct pci_bus *bus, u16 link_status);
> +#ifdef CONFIG_SYSFS
> +void pci_dev_assign_slot(struct pci_dev *dev);
> struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
> const char *name,
> struct hotplug_slot *hotplug);
> void pci_destroy_slot(struct pci_slot *slot);
> -#ifdef CONFIG_SYSFS
> -void pci_dev_assign_slot(struct pci_dev *dev);
> #else
> static inline void pci_dev_assign_slot(struct pci_dev *dev) { }
> +static inline struct pci_slot *pci_create_slot(struct pci_bus *parent,
> + int slot_nr,
> + const char *name,
> + struct hotplug_slot *hotplug) {
> + return ERR_PTR(-EINVAL);
> +}
> +static inline void pci_destroy_slot(struct pci_slot *slot) { }
> #endif
> int pci_scan_slot(struct pci_bus *bus, int devfn);
> struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn);
>

The serial number in slot info is used to match VF NIC with Synthetic NIC.
Without selecting SYSFS, the SRIOV feature will fail on VM on Hyper-V and
Azure. The first version of this patch should be used.

@Stephen Hemminger how do you think?

Thanks,
- Haiyang

2019-07-07 18:03:51

by Randy Dunlap

[permalink] [raw]
Subject: Re: [PATCH v2] PCI: hv: fix pci-hyperv build when SYSFS not enabled

On 7/3/19 11:06 AM, Haiyang Zhang wrote:
>
>
>> -----Original Message-----
>> From: Randy Dunlap <[email protected]>
>> Sent: Wednesday, July 3, 2019 12:59 PM
>> To: LKML <[email protected]>; linux-pci <linux-
>> [email protected]>
>> Cc: Matthew Wilcox <[email protected]>; Jake Oshins
>> <[email protected]>; KY Srinivasan <[email protected]>; Haiyang
>> Zhang <[email protected]>; Stephen Hemminger
>> <[email protected]>; Sasha Levin <[email protected]>; Bjorn
>> Helgaas <[email protected]>; [email protected]; Dexuan
>> Cui <[email protected]>; Yuehaibing <[email protected]>
>> Subject: [PATCH v2] PCI: hv: fix pci-hyperv build when SYSFS not enabled
>>
>> From: Randy Dunlap <[email protected]>
>>
>> Fix build of drivers/pci/controller/pci-hyperv.o when
>> CONFIG_SYSFS is not set/enabled by adding stubs for
>> pci_create_slot() and pci_destroy_slot().
>>
>> Fixes these build errors:
>>
>> ERROR: "pci_destroy_slot" [drivers/pci/controller/pci-hyperv.ko] undefined!
>> ERROR: "pci_create_slot" [drivers/pci/controller/pci-hyperv.ko] undefined!
>>
>> Fixes: a15f2c08c708 ("PCI: hv: support reporting serial number as slot
>> information")
>>
>> Signed-off-by: Randy Dunlap <[email protected]>
>> Cc: Matthew Wilcox <[email protected]>
>> Cc: Jake Oshins <[email protected]>
>> Cc: "K. Y. Srinivasan" <[email protected]>
>> Cc: Haiyang Zhang <[email protected]>
>> Cc: Stephen Hemminger <[email protected]>
>> Cc: Sasha Levin <[email protected]>
>> Cc: Bjorn Helgaas <[email protected]>
>> Cc: [email protected]
>> Cc: [email protected]
>> Cc: Dexuan Cui <[email protected]>
>> Cc: Yuehaibing <[email protected]>
>> ---
>> v2:
>> - provide non-CONFIG_SYSFS stubs for pci_create_slot() and
>> pci_destroy_slot() [suggested by Matthew Wilcox <[email protected]>]
>> - use the correct Fixes: tag [Dexuan Cui <[email protected]>]
>>
>> include/linux/pci.h | 12 ++++++++++--
>> 1 file changed, 10 insertions(+), 2 deletions(-)
>>
>> --- lnx-52-rc7.orig/include/linux/pci.h
>> +++ lnx-52-rc7/include/linux/pci.h
>> @@ -25,6 +25,7 @@
>> #include <linux/ioport.h>
>> #include <linux/list.h>
>> #include <linux/compiler.h>
>> +#include <linux/err.h>
>> #include <linux/errno.h>
>> #include <linux/kobject.h>
>> #include <linux/atomic.h>
>> @@ -947,14 +948,21 @@ int pci_scan_root_bus_bridge(struct pci_
>> struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev
>> *dev,
>> int busnr);
>> void pcie_update_link_speed(struct pci_bus *bus, u16 link_status);
>> +#ifdef CONFIG_SYSFS
>> +void pci_dev_assign_slot(struct pci_dev *dev);
>> struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
>> const char *name,
>> struct hotplug_slot *hotplug);
>> void pci_destroy_slot(struct pci_slot *slot);
>> -#ifdef CONFIG_SYSFS
>> -void pci_dev_assign_slot(struct pci_dev *dev);
>> #else
>> static inline void pci_dev_assign_slot(struct pci_dev *dev) { }
>> +static inline struct pci_slot *pci_create_slot(struct pci_bus *parent,
>> + int slot_nr,
>> + const char *name,
>> + struct hotplug_slot *hotplug) {
>> + return ERR_PTR(-EINVAL);
>> +}
>> +static inline void pci_destroy_slot(struct pci_slot *slot) { }
>> #endif
>> int pci_scan_slot(struct pci_bus *bus, int devfn);
>> struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn);
>>
>
> The serial number in slot info is used to match VF NIC with Synthetic NIC.
> Without selecting SYSFS, the SRIOV feature will fail on VM on Hyper-V and
> Azure. The first version of this patch should be used.
>
> @Stephen Hemminger how do you think?
>
> Thanks,
> - Haiyang


Hi Stephen,

Please comment on this patch or v1.
v1: https://lore.kernel.org/lkml/[email protected]/


thanks.
--
~Randy

2019-07-08 19:28:26

by Stephen Hemminger

[permalink] [raw]
Subject: Re: [PATCH v2] PCI: hv: fix pci-hyperv build when SYSFS not enabled

On Sun, 7 Jul 2019 10:46:22 -0700
Randy Dunlap <[email protected]> wrote:

> On 7/3/19 11:06 AM, Haiyang Zhang wrote:
> >
> >
> >> -----Original Message-----
> >> From: Randy Dunlap <[email protected]>
> >> Sent: Wednesday, July 3, 2019 12:59 PM
> >> To: LKML <[email protected]>; linux-pci <linux-
> >> [email protected]>
> >> Cc: Matthew Wilcox <[email protected]>; Jake Oshins
> >> <[email protected]>; KY Srinivasan <[email protected]>; Haiyang
> >> Zhang <[email protected]>; Stephen Hemminger
> >> <[email protected]>; Sasha Levin <[email protected]>; Bjorn
> >> Helgaas <[email protected]>; [email protected]; Dexuan
> >> Cui <[email protected]>; Yuehaibing <[email protected]>
> >> Subject: [PATCH v2] PCI: hv: fix pci-hyperv build when SYSFS not enabled
> >>
> >> From: Randy Dunlap <[email protected]>
> >>
> >> Fix build of drivers/pci/controller/pci-hyperv.o when
> >> CONFIG_SYSFS is not set/enabled by adding stubs for
> >> pci_create_slot() and pci_destroy_slot().
> >>
> >> Fixes these build errors:
> >>
> >> ERROR: "pci_destroy_slot" [drivers/pci/controller/pci-hyperv.ko] undefined!
> >> ERROR: "pci_create_slot" [drivers/pci/controller/pci-hyperv.ko] undefined!
> >>
> >> Fixes: a15f2c08c708 ("PCI: hv: support reporting serial number as slot
> >> information")
> >>
> >> Signed-off-by: Randy Dunlap <[email protected]>
> >> Cc: Matthew Wilcox <[email protected]>
> >> Cc: Jake Oshins <[email protected]>
> >> Cc: "K. Y. Srinivasan" <[email protected]>
> >> Cc: Haiyang Zhang <[email protected]>
> >> Cc: Stephen Hemminger <[email protected]>
> >> Cc: Sasha Levin <[email protected]>
> >> Cc: Bjorn Helgaas <[email protected]>
> >> Cc: [email protected]
> >> Cc: [email protected]
> >> Cc: Dexuan Cui <[email protected]>
> >> Cc: Yuehaibing <[email protected]>
> >> ---
> >> v2:
> >> - provide non-CONFIG_SYSFS stubs for pci_create_slot() and
> >> pci_destroy_slot() [suggested by Matthew Wilcox <[email protected]>]
> >> - use the correct Fixes: tag [Dexuan Cui <[email protected]>]
> >>
> >> include/linux/pci.h | 12 ++++++++++--
> >> 1 file changed, 10 insertions(+), 2 deletions(-)
> >>
> >> --- lnx-52-rc7.orig/include/linux/pci.h
> >> +++ lnx-52-rc7/include/linux/pci.h
> >> @@ -25,6 +25,7 @@
> >> #include <linux/ioport.h>
> >> #include <linux/list.h>
> >> #include <linux/compiler.h>
> >> +#include <linux/err.h>
> >> #include <linux/errno.h>
> >> #include <linux/kobject.h>
> >> #include <linux/atomic.h>
> >> @@ -947,14 +948,21 @@ int pci_scan_root_bus_bridge(struct pci_
> >> struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev
> >> *dev,
> >> int busnr);
> >> void pcie_update_link_speed(struct pci_bus *bus, u16 link_status);
> >> +#ifdef CONFIG_SYSFS
> >> +void pci_dev_assign_slot(struct pci_dev *dev);
> >> struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
> >> const char *name,
> >> struct hotplug_slot *hotplug);
> >> void pci_destroy_slot(struct pci_slot *slot);
> >> -#ifdef CONFIG_SYSFS
> >> -void pci_dev_assign_slot(struct pci_dev *dev);
> >> #else
> >> static inline void pci_dev_assign_slot(struct pci_dev *dev) { }
> >> +static inline struct pci_slot *pci_create_slot(struct pci_bus *parent,
> >> + int slot_nr,
> >> + const char *name,
> >> + struct hotplug_slot *hotplug) {
> >> + return ERR_PTR(-EINVAL);
> >> +}
> >> +static inline void pci_destroy_slot(struct pci_slot *slot) { }
> >> #endif
> >> int pci_scan_slot(struct pci_bus *bus, int devfn);
> >> struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn);
> >>
> >
> > The serial number in slot info is used to match VF NIC with Synthetic NIC.
> > Without selecting SYSFS, the SRIOV feature will fail on VM on Hyper-V and
> > Azure. The first version of this patch should be used.
> >
> > @Stephen Hemminger how do you think?

Haiyang is right, accelerated networking won't work if slot is not recorded.

So the original patch (to depend on SYSFS) or using "select SYSFS" is
are necessary.

The whole thing is a bit of "angels dancing on the head of a pin" because
there is no good reason to build kernel without SYSFS in real world.
It would just be looking for trouble. As far as I can tell it is all
about getting "make randconfig" to work in more cases.


2019-07-09 00:55:42

by Randy Dunlap

[permalink] [raw]
Subject: Re: [PATCH v2] PCI: hv: fix pci-hyperv build when SYSFS not enabled

On 7/8/19 8:05 AM, Stephen Hemminger wrote:
> On Sun, 7 Jul 2019 10:46:22 -0700
> Randy Dunlap <[email protected]> wrote:
>
>> On 7/3/19 11:06 AM, Haiyang Zhang wrote:
>>>
>>>
>>>> -----Original Message-----
>>>> From: Randy Dunlap <[email protected]>
>>>> Sent: Wednesday, July 3, 2019 12:59 PM
>>>> To: LKML <[email protected]>; linux-pci <linux-
>>>> [email protected]>
>>>> Cc: Matthew Wilcox <[email protected]>; Jake Oshins
>>>> <[email protected]>; KY Srinivasan <[email protected]>; Haiyang
>>>> Zhang <[email protected]>; Stephen Hemminger
>>>> <[email protected]>; Sasha Levin <[email protected]>; Bjorn
>>>> Helgaas <[email protected]>; [email protected]; Dexuan
>>>> Cui <[email protected]>; Yuehaibing <[email protected]>
>>>> Subject: [PATCH v2] PCI: hv: fix pci-hyperv build when SYSFS not enabled
>>>>
>>>> From: Randy Dunlap <[email protected]>
>>>>
>>>> Fix build of drivers/pci/controller/pci-hyperv.o when
>>>> CONFIG_SYSFS is not set/enabled by adding stubs for
>>>> pci_create_slot() and pci_destroy_slot().
>>>>
>>>> Fixes these build errors:
>>>>
>>>> ERROR: "pci_destroy_slot" [drivers/pci/controller/pci-hyperv.ko] undefined!
>>>> ERROR: "pci_create_slot" [drivers/pci/controller/pci-hyperv.ko] undefined!
>>>>
>>>> Fixes: a15f2c08c708 ("PCI: hv: support reporting serial number as slot
>>>> information")
>>>>
>>>> Signed-off-by: Randy Dunlap <[email protected]>
>>>> Cc: Matthew Wilcox <[email protected]>
>>>> Cc: Jake Oshins <[email protected]>
>>>> Cc: "K. Y. Srinivasan" <[email protected]>
>>>> Cc: Haiyang Zhang <[email protected]>
>>>> Cc: Stephen Hemminger <[email protected]>
>>>> Cc: Sasha Levin <[email protected]>
>>>> Cc: Bjorn Helgaas <[email protected]>
>>>> Cc: [email protected]
>>>> Cc: [email protected]
>>>> Cc: Dexuan Cui <[email protected]>
>>>> Cc: Yuehaibing <[email protected]>
>>>> ---
>>>> v2:
>>>> - provide non-CONFIG_SYSFS stubs for pci_create_slot() and
>>>> pci_destroy_slot() [suggested by Matthew Wilcox <[email protected]>]
>>>> - use the correct Fixes: tag [Dexuan Cui <[email protected]>]
>>>>
>>>> include/linux/pci.h | 12 ++++++++++--
>>>> 1 file changed, 10 insertions(+), 2 deletions(-)
>>>>
>>>> --- lnx-52-rc7.orig/include/linux/pci.h
>>>> +++ lnx-52-rc7/include/linux/pci.h
>>>> @@ -25,6 +25,7 @@
>>>> #include <linux/ioport.h>
>>>> #include <linux/list.h>
>>>> #include <linux/compiler.h>
>>>> +#include <linux/err.h>
>>>> #include <linux/errno.h>
>>>> #include <linux/kobject.h>
>>>> #include <linux/atomic.h>
>>>> @@ -947,14 +948,21 @@ int pci_scan_root_bus_bridge(struct pci_
>>>> struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev
>>>> *dev,
>>>> int busnr);
>>>> void pcie_update_link_speed(struct pci_bus *bus, u16 link_status);
>>>> +#ifdef CONFIG_SYSFS
>>>> +void pci_dev_assign_slot(struct pci_dev *dev);
>>>> struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
>>>> const char *name,
>>>> struct hotplug_slot *hotplug);
>>>> void pci_destroy_slot(struct pci_slot *slot);
>>>> -#ifdef CONFIG_SYSFS
>>>> -void pci_dev_assign_slot(struct pci_dev *dev);
>>>> #else
>>>> static inline void pci_dev_assign_slot(struct pci_dev *dev) { }
>>>> +static inline struct pci_slot *pci_create_slot(struct pci_bus *parent,
>>>> + int slot_nr,
>>>> + const char *name,
>>>> + struct hotplug_slot *hotplug) {
>>>> + return ERR_PTR(-EINVAL);
>>>> +}
>>>> +static inline void pci_destroy_slot(struct pci_slot *slot) { }
>>>> #endif
>>>> int pci_scan_slot(struct pci_bus *bus, int devfn);
>>>> struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn);
>>>>
>>>
>>> The serial number in slot info is used to match VF NIC with Synthetic NIC.
>>> Without selecting SYSFS, the SRIOV feature will fail on VM on Hyper-V and
>>> Azure. The first version of this patch should be used.
>>>
>>> @Stephen Hemminger how do you think?
>
> Haiyang is right, accelerated networking won't work if slot is not recorded.
>
> So the original patch (to depend on SYSFS) or using "select SYSFS" is
> are necessary.

Thanks, I'll resend that one with the corrected Fixes: tag.

> The whole thing is a bit of "angels dancing on the head of a pin" because
> there is no good reason to build kernel without SYSFS in real world.
> It would just be looking for trouble. As far as I can tell it is all
> about getting "make randconfig" to work in more cases.

You could submit a patch to remove the SYSFS kconfig entry. :)

cheers.

--
~Randy