[PATCHv6 0/5] Limiting PCI access

[PATCHv6 0/5] Limiting PCI access

[Keith Busch]

The code is functionally equivalent to v5. I've fixed the style
points mentioned in review on line warpping, adjusted the change log
on the msi/msix skippage to not exclude mentioning msi, and added the
accumulated Reviewed-by's.

Keith Busch (5):
  pci: Export pci device config accessors
  pci: Add device disconnected state
  pci: No config access for disconnected devices
  pci/msix: Skip disabling disconnected devices
  pci: Quick return for pci_device_is_present

 drivers/pci/access.c             | 56 ++++++++++++++++++++++++++++++++++++++++
 drivers/pci/hotplug/pciehp_pci.c |  6 +++++
 drivers/pci/msi.c                |  7 ++++-
 drivers/pci/pci.c                |  2 ++
 drivers/pci/pci.h                | 14 ++++++++++
 drivers/pci/pcie/pcie-dpc.c      |  5 ++++
 include/linux/pci.h              | 34 ++++++------------------
 7 files changed, 97 insertions(+), 27 deletions(-)

-- 
2.7.2

[PATCHv6 1/5] pci: Export pci device config accessors

[Keith Busch]

This patch replaces the inline pci device config read and write accessors
with exported functions. This is preparing for these functions to make
use of private data.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 drivers/pci/access.c | 38 ++++++++++++++++++++++++++++++++++++++
 include/linux/pci.h  | 32 ++++++--------------------------
 2 files changed, 44 insertions(+), 26 deletions(-)

diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index db23954..d37b2ed 100644
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -889,3 +889,41 @@ int pcie_capability_clear_and_set_dword(struct pci_dev *dev, int pos,
 	return ret;
 }
 EXPORT_SYMBOL(pcie_capability_clear_and_set_dword);
+
+int pci_read_config_byte(const struct pci_dev *dev, int where, u8 *val)
+{
+	return pci_bus_read_config_byte(dev->bus, dev->devfn, where, val);
+}
+EXPORT_SYMBOL(pci_read_config_byte);
+
+int pci_read_config_word(const struct pci_dev *dev, int where, u16 *val)
+{
+	return pci_bus_read_config_word(dev->bus, dev->devfn, where, val);
+}
+EXPORT_SYMBOL(pci_read_config_word);
+
+int pci_read_config_dword(const struct pci_dev *dev, int where,
+					u32 *val)
+{
+	return pci_bus_read_config_dword(dev->bus, dev->devfn, where, val);
+}
+EXPORT_SYMBOL(pci_read_config_dword);
+
+int pci_write_config_byte(const struct pci_dev *dev, int where, u8 val)
+{
+	return pci_bus_write_config_byte(dev->bus, dev->devfn, where, val);
+}
+EXPORT_SYMBOL(pci_write_config_byte);
+
+int pci_write_config_word(const struct pci_dev *dev, int where, u16 val)
+{
+	return pci_bus_write_config_word(dev->bus, dev->devfn, where, val);
+}
+EXPORT_SYMBOL(pci_write_config_word);
+
+int pci_write_config_dword(const struct pci_dev *dev, int where,
+					 u32 val)
+{
+	return pci_bus_write_config_dword(dev->bus, dev->devfn, where, val);
+}
+EXPORT_SYMBOL(pci_write_config_dword);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index e2d1a12..b00a2d3 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -944,32 +944,12 @@ int pci_generic_config_write32(struct pci_bus *bus, unsigned int devfn,
 
 struct pci_ops *pci_bus_set_ops(struct pci_bus *bus, struct pci_ops *ops);
 
-static inline int pci_read_config_byte(const struct pci_dev *dev, int where, u8 *val)
-{
-	return pci_bus_read_config_byte(dev->bus, dev->devfn, where, val);
-}
-static inline int pci_read_config_word(const struct pci_dev *dev, int where, u16 *val)
-{
-	return pci_bus_read_config_word(dev->bus, dev->devfn, where, val);
-}
-static inline int pci_read_config_dword(const struct pci_dev *dev, int where,
-					u32 *val)
-{
-	return pci_bus_read_config_dword(dev->bus, dev->devfn, where, val);
-}
-static inline int pci_write_config_byte(const struct pci_dev *dev, int where, u8 val)
-{
-	return pci_bus_write_config_byte(dev->bus, dev->devfn, where, val);
-}
-static inline int pci_write_config_word(const struct pci_dev *dev, int where, u16 val)
-{
-	return pci_bus_write_config_word(dev->bus, dev->devfn, where, val);
-}
-static inline int pci_write_config_dword(const struct pci_dev *dev, int where,
-					 u32 val)
-{
-	return pci_bus_write_config_dword(dev->bus, dev->devfn, where, val);
-}
+int pci_read_config_byte(const struct pci_dev *dev, int where, u8 *val);
+int pci_read_config_word(const struct pci_dev *dev, int where, u16 *val);
+int pci_read_config_dword(const struct pci_dev *dev, int where, u32 *val);
+int pci_write_config_byte(const struct pci_dev *dev, int where, u8 val);
+int pci_write_config_word(const struct pci_dev *dev, int where, u16 val);
+int pci_write_config_dword(const struct pci_dev *dev, int where, u32 val);
 
 int pcie_capability_read_word(struct pci_dev *dev, int pos, u16 *val);
 int pcie_capability_read_dword(struct pci_dev *dev, int pos, u32 *val);
-- 
2.7.2

[PATCHv6 2/5] pci: Add device disconnected state

[Keith Busch]

This patch adds a new state to pci_dev to be set when it is unexpectedly
disconnected. The pci driver tear down functions can observe this new
device state so they may skip operations that will fail.

The pciehp and pcie-dpc drivers are aware when the link is down, so
these set the flag when their handlers detect the device is disconnected.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 drivers/pci/hotplug/pciehp_pci.c |  6 ++++++
 drivers/pci/pci.h                | 14 ++++++++++++++
 drivers/pci/pcie/pcie-dpc.c      |  5 +++++
 include/linux/pci.h              |  2 ++
 4 files changed, 27 insertions(+)

diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c
index 9e69403..19f30a9 100644
--- a/drivers/pci/hotplug/pciehp_pci.c
+++ b/drivers/pci/hotplug/pciehp_pci.c
@@ -109,6 +109,12 @@ int pciehp_unconfigure_device(struct slot *p_slot)
 				break;
 			}
 		}
+		if (!presence) {
+			pci_dev_set_disconnected(dev, NULL);
+			if (pci_has_subordinate(dev))
+				pci_walk_bus(dev->subordinate,
+					     pci_dev_set_disconnected, NULL);
+		}
 		pci_stop_and_remove_bus_device(dev);
 		/*
 		 * Ensure that no new Requests will be generated from
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index cb17db2..81512bc 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -274,6 +274,20 @@ struct pci_sriov {
 	resource_size_t barsz[PCI_SRIOV_NUM_BARS];	/* VF BAR size */
 };
 
+/* pci_dev priv_flags */
+#define PCI_DEV_DISCONNECTED 0
+
+static inline int pci_dev_set_disconnected(struct pci_dev *dev, void *unused)
+{
+	set_bit(PCI_DEV_DISCONNECTED, &dev->priv_flags);
+	return 0;
+}
+
+static inline bool pci_dev_is_disconnected(const struct pci_dev *dev)
+{
+	return test_bit(PCI_DEV_DISCONNECTED, &dev->priv_flags);
+}
+
 #ifdef CONFIG_PCI_ATS
 void pci_restore_ats_state(struct pci_dev *dev);
 #else
diff --git a/drivers/pci/pcie/pcie-dpc.c b/drivers/pci/pcie/pcie-dpc.c
index 9811b14..1480458 100644
--- a/drivers/pci/pcie/pcie-dpc.c
+++ b/drivers/pci/pcie/pcie-dpc.c
@@ -14,6 +14,7 @@
 #include <linux/init.h>
 #include <linux/pci.h>
 #include <linux/pcieport_if.h>
+#include "../pci.h"
 
 struct dpc_dev {
 	struct pcie_device	*dev;
@@ -46,6 +47,10 @@ static void interrupt_event_handler(struct work_struct *work)
 	list_for_each_entry_safe_reverse(dev, temp, &parent->devices,
 					 bus_list) {
 		pci_dev_get(dev);
+		pci_dev_set_disconnected(dev, NULL);
+		if (pci_has_subordinate(dev))
+			pci_walk_bus(dev->subordinate,
+				     pci_dev_set_disconnected, NULL);
 		pci_stop_and_remove_bus_device(dev);
 		pci_dev_put(dev);
 	}
diff --git a/include/linux/pci.h b/include/linux/pci.h
index b00a2d3..5d17f1b 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -396,6 +396,8 @@ struct pci_dev {
 	phys_addr_t rom; /* Physical address of ROM if it's not from the BAR */
 	size_t romlen; /* Length of ROM if it's not from the BAR */
 	char *driver_override; /* Driver name to force a match */
+
+	unsigned long priv_flags; /* Private flags for the pci driver */
 };
 
 static inline struct pci_dev *pci_physfn(struct pci_dev *dev)
-- 
2.7.2

[PATCHv6 3/5] pci: No config access for disconnected devices

[Keith Busch]

If we've  detected the PCI device is disconnected, there is no need to
attempt to access its config space since we know the operation will
fail. This patch has all the config reads and writes return -ENODEV
error immediately when in such a state.

If a config read is sent to a disconnected device, the value will be
set to all 1's. This is the same as what hardware is expected to return
when accessing a removed device, but software can do this faster without
relying on hardware.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 drivers/pci/access.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index d37b2ed..d63e9dd 100644
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -892,12 +892,20 @@ EXPORT_SYMBOL(pcie_capability_clear_and_set_dword);
 
 int pci_read_config_byte(const struct pci_dev *dev, int where, u8 *val)
 {
+	if (pci_dev_is_disconnected(dev)) {
+		*val = ~0;
+		return -ENODEV;
+	}
 	return pci_bus_read_config_byte(dev->bus, dev->devfn, where, val);
 }
 EXPORT_SYMBOL(pci_read_config_byte);
 
 int pci_read_config_word(const struct pci_dev *dev, int where, u16 *val)
 {
+	if (pci_dev_is_disconnected(dev)) {
+		*val = ~0;
+		return -ENODEV;
+	}
 	return pci_bus_read_config_word(dev->bus, dev->devfn, where, val);
 }
 EXPORT_SYMBOL(pci_read_config_word);
@@ -905,18 +913,26 @@ EXPORT_SYMBOL(pci_read_config_word);
 int pci_read_config_dword(const struct pci_dev *dev, int where,
 					u32 *val)
 {
+	if (pci_dev_is_disconnected(dev)) {
+		*val = ~0;
+		return -ENODEV;
+	}
 	return pci_bus_read_config_dword(dev->bus, dev->devfn, where, val);
 }
 EXPORT_SYMBOL(pci_read_config_dword);
 
 int pci_write_config_byte(const struct pci_dev *dev, int where, u8 val)
 {
+	if (pci_dev_is_disconnected(dev))
+		return -ENODEV;
 	return pci_bus_write_config_byte(dev->bus, dev->devfn, where, val);
 }
 EXPORT_SYMBOL(pci_write_config_byte);
 
 int pci_write_config_word(const struct pci_dev *dev, int where, u16 val)
 {
+	if (pci_dev_is_disconnected(dev))
+		return -ENODEV;
 	return pci_bus_write_config_word(dev->bus, dev->devfn, where, val);
 }
 EXPORT_SYMBOL(pci_write_config_word);
@@ -924,6 +940,8 @@ EXPORT_SYMBOL(pci_write_config_word);
 int pci_write_config_dword(const struct pci_dev *dev, int where,
 					 u32 val)
 {
+	if (pci_dev_is_disconnected(dev))
+		return -ENODEV;
 	return pci_bus_write_config_dword(dev->bus, dev->devfn, where, val);
 }
 EXPORT_SYMBOL(pci_write_config_dword);
-- 
2.7.2

[PATCHv6 4/5] pci/msix: Skip disabling disconnected devices

[Keith Busch]

This patch checks the device connected state prior to executing device
shutdown operations or writing msi messages so that tear down on
disconnected devices completes quicker.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 drivers/pci/msi.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 50c5003..17807eb3 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -317,7 +317,7 @@ void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 {
 	struct pci_dev *dev = msi_desc_to_pci_dev(entry);
 
-	if (dev->current_state != PCI_D0) {
+	if (dev->current_state != PCI_D0 || pci_dev_is_disconnected(dev)) {
 		/* Don't touch the hardware now */
 	} else if (entry->msi_attrib.is_msix) {
 		void __iomem *base = pci_msix_desc_addr(entry);
@@ -1020,6 +1020,11 @@ void pci_msix_shutdown(struct pci_dev *dev)
 	if (!pci_msi_enable || !dev || !dev->msix_enabled)
 		return;
 
+	if (pci_dev_is_disconnected(dev)) {
+		dev->msix_enabled = 0;
+		return;
+	}
+
 	/* Return the device with MSI-X masked as initial states */
 	for_each_pci_msi_entry(entry, dev) {
 		/* Keep cached states to be restored */
-- 
2.7.2

[PATCHv6 5/5] pci: Quick return for pci_device_is_present

[Keith Busch]

If the pci device is disconnected, return false immediately for checking
presence. We can't use the early return in pci device config accessors
since this function uses the bus accessors.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 drivers/pci/pci.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index a881c0d..b8d37e7 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4932,6 +4932,8 @@ bool pci_device_is_present(struct pci_dev *pdev)
 {
 	u32 v;
 
+	if (pci_dev_is_disconnected(pdev))
+		return false;
 	return pci_bus_read_dev_vendor_id(pdev->bus, pdev->devfn, &v, 0);
 }
 EXPORT_SYMBOL_GPL(pci_device_is_present);
-- 
2.7.2

Re: [PATCHv6 3/5] pci: No config access for disconnected devices

[Lukas Wunner]

On Tue, Feb 07, 2017 at 02:32:35PM -0500, Keith Busch wrote:
> If we've  detected the PCI device is disconnected, there is no need to
> attempt to access its config space since we know the operation will
> fail. This patch has all the config reads and writes return -ENODEV
> error immediately when in such a state.
> 
> If a config read is sent to a disconnected device, the value will be
> set to all 1's. This is the same as what hardware is expected to return
> when accessing a removed device, but software can do this faster without
> relying on hardware.
> 
> Signed-off-by: Keith Busch <keith.busch@intel.com>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> ---
>  drivers/pci/access.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/drivers/pci/access.c b/drivers/pci/access.c
> index d37b2ed..d63e9dd 100644
> --- a/drivers/pci/access.c
> +++ b/drivers/pci/access.c
> @@ -892,12 +892,20 @@ EXPORT_SYMBOL(pcie_capability_clear_and_set_dword);
>  
>  int pci_read_config_byte(const struct pci_dev *dev, int where, u8 *val)
>  {
> +	if (pci_dev_is_disconnected(dev)) {

You used to have unlikely() here up until v4 but dropped it in v5.
Why?  Seemed sensible to me.

Thanks,

Lukas

> +		*val = ~0;
> +		return -ENODEV;
> +	}
>  	return pci_bus_read_config_byte(dev->bus, dev->devfn, where, val);
>  }
>  EXPORT_SYMBOL(pci_read_config_byte);
>  
>  int pci_read_config_word(const struct pci_dev *dev, int where, u16 *val)
>  {
> +	if (pci_dev_is_disconnected(dev)) {
> +		*val = ~0;
> +		return -ENODEV;
> +	}
>  	return pci_bus_read_config_word(dev->bus, dev->devfn, where, val);
>  }
>  EXPORT_SYMBOL(pci_read_config_word);
> @@ -905,18 +913,26 @@ EXPORT_SYMBOL(pci_read_config_word);
>  int pci_read_config_dword(const struct pci_dev *dev, int where,
>  					u32 *val)
>  {
> +	if (pci_dev_is_disconnected(dev)) {
> +		*val = ~0;
> +		return -ENODEV;
> +	}
>  	return pci_bus_read_config_dword(dev->bus, dev->devfn, where, val);
>  }
>  EXPORT_SYMBOL(pci_read_config_dword);
>  
>  int pci_write_config_byte(const struct pci_dev *dev, int where, u8 val)
>  {
> +	if (pci_dev_is_disconnected(dev))
> +		return -ENODEV;
>  	return pci_bus_write_config_byte(dev->bus, dev->devfn, where, val);
>  }
>  EXPORT_SYMBOL(pci_write_config_byte);
>  
>  int pci_write_config_word(const struct pci_dev *dev, int where, u16 val)
>  {
> +	if (pci_dev_is_disconnected(dev))
> +		return -ENODEV;
>  	return pci_bus_write_config_word(dev->bus, dev->devfn, where, val);
>  }
>  EXPORT_SYMBOL(pci_write_config_word);
> @@ -924,6 +940,8 @@ EXPORT_SYMBOL(pci_write_config_word);
>  int pci_write_config_dword(const struct pci_dev *dev, int where,
>  					 u32 val)
>  {
> +	if (pci_dev_is_disconnected(dev))
> +		return -ENODEV;
>  	return pci_bus_write_config_dword(dev->bus, dev->devfn, where, val);
>  }
>  EXPORT_SYMBOL(pci_write_config_dword);
> -- 
> 2.7.2
> 

Re: [PATCHv6 3/5] pci: No config access for disconnected devices

[Keith Busch]

On Wed, Feb 08, 2017 at 07:04:10AM +0100, Lukas Wunner wrote:
> On Tue, Feb 07, 2017 at 02:32:35PM -0500, Keith Busch wrote:
> > If we've  detected the PCI device is disconnected, there is no need to
> > attempt to access its config space since we know the operation will
> > fail. This patch has all the config reads and writes return -ENODEV
> > error immediately when in such a state.
> > 
> > If a config read is sent to a disconnected device, the value will be
> > set to all 1's. This is the same as what hardware is expected to return
> > when accessing a removed device, but software can do this faster without
> > relying on hardware.
> > 
> > Signed-off-by: Keith Busch <keith.busch@intel.com>
> > Reviewed-by: Christoph Hellwig <hch@lst.de>
> > ---
> >  drivers/pci/access.c | 18 ++++++++++++++++++
> >  1 file changed, 18 insertions(+)
> > 
> > diff --git a/drivers/pci/access.c b/drivers/pci/access.c
> > index d37b2ed..d63e9dd 100644
> > --- a/drivers/pci/access.c
> > +++ b/drivers/pci/access.c
> > @@ -892,12 +892,20 @@ EXPORT_SYMBOL(pcie_capability_clear_and_set_dword);
> >  
> >  int pci_read_config_byte(const struct pci_dev *dev, int where, u8 *val)
> >  {
> > +	if (pci_dev_is_disconnected(dev)) {
> 
> You used to have unlikely() here up until v4 but dropped it in v5.
> Why?  Seemed sensible to me.

Didn't mean to remove the unlikely. The micro-optimization isn't in a
performance path, but I'll build it back in.

Re: [PATCHv6 3/5] pci: No config access for disconnected devices

[Greg Kroah-Hartman]

On Fri, Feb 10, 2017 at 01:38:52PM -0500, Keith Busch wrote:
> On Wed, Feb 08, 2017 at 07:04:10AM +0100, Lukas Wunner wrote:
> > On Tue, Feb 07, 2017 at 02:32:35PM -0500, Keith Busch wrote:
> > > If we've  detected the PCI device is disconnected, there is no need to
> > > attempt to access its config space since we know the operation will
> > > fail. This patch has all the config reads and writes return -ENODEV
> > > error immediately when in such a state.
> > > 
> > > If a config read is sent to a disconnected device, the value will be
> > > set to all 1's. This is the same as what hardware is expected to return
> > > when accessing a removed device, but software can do this faster without
> > > relying on hardware.
> > > 
> > > Signed-off-by: Keith Busch <keith.busch@intel.com>
> > > Reviewed-by: Christoph Hellwig <hch@lst.de>
> > > ---
> > >  drivers/pci/access.c | 18 ++++++++++++++++++
> > >  1 file changed, 18 insertions(+)
> > > 
> > > diff --git a/drivers/pci/access.c b/drivers/pci/access.c
> > > index d37b2ed..d63e9dd 100644
> > > --- a/drivers/pci/access.c
> > > +++ b/drivers/pci/access.c
> > > @@ -892,12 +892,20 @@ EXPORT_SYMBOL(pcie_capability_clear_and_set_dword);
> > >  
> > >  int pci_read_config_byte(const struct pci_dev *dev, int where, u8 *val)
> > >  {
> > > +	if (pci_dev_is_disconnected(dev)) {
> > 
> > You used to have unlikely() here up until v4 but dropped it in v5.
> > Why?  Seemed sensible to me.
> 
> Didn't mean to remove the unlikely. The micro-optimization isn't in a
> performance path, but I'll build it back in.

Only do so if you can measure the difference, otherwise it is useless,
and can actually hurt.

thanks,

greg k-h

Re: [PATCHv6 3/5] pci: No config access for disconnected devices

[Keith Busch]

On Fri, Feb 10, 2017 at 08:54:13PM +0100, Greg Kroah-Hartman wrote:
> On Fri, Feb 10, 2017 at 01:38:52PM -0500, Keith Busch wrote:
> > Didn't mean to remove the unlikely. The micro-optimization isn't in a
> > performance path, but I'll build it back in.
> 
> Only do so if you can measure the difference, otherwise it is useless,
> and can actually hurt.

Okay, that sounds good to me then, and I can't measure a difference here
in either case.

Bjorn,
What do you think? Is this series okay or any other conerncs I may
help address?

Thanks,
Keith

Re: [PATCHv6 0/5] Limiting PCI access

[Wei Zhang]

SGkgRm9sa3MsDQoNClRoaXMgc2VyaWVzIG9mIHBhdGNoZXMgaXMgY3JpdGljYWwgaW4gc3VwcG9y
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Re: [PATCHv6 0/5] Limiting PCI access

[Bjorn Helgaas]

On Tue, Feb 07, 2017 at 02:32:32PM -0500, Keith Busch wrote:
> The code is functionally equivalent to v5. I've fixed the style
> points mentioned in review on line warpping, adjusted the change log
> on the msi/msix skippage to not exclude mentioning msi, and added the
> accumulated Reviewed-by's.
> 
> Keith Busch (5):
>   pci: Export pci device config accessors
>   pci: Add device disconnected state
>   pci: No config access for disconnected devices
>   pci/msix: Skip disabling disconnected devices
>   pci: Quick return for pci_device_is_present
> 
>  drivers/pci/access.c             | 56 ++++++++++++++++++++++++++++++++++++++++
>  drivers/pci/hotplug/pciehp_pci.c |  6 +++++
>  drivers/pci/msi.c                |  7 ++++-
>  drivers/pci/pci.c                |  2 ++
>  drivers/pci/pci.h                | 14 ++++++++++
>  drivers/pci/pcie/pcie-dpc.c      |  5 ++++
>  include/linux/pci.h              | 34 ++++++------------------
>  7 files changed, 97 insertions(+), 27 deletions(-)

Applied to pci/enumeration for v4.12 with

  Tested-by: Krishna Dhulipala <krishnad@fb.com>
  Reviewed-by: Wei Zhang <wzhang@fb.com>

Thanks!

Re: [PATCHv6 0/5] Limiting PCI access

[Wei Zhang]

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