Re: [PATCH] PCI: Make pci_find_upstream_pcie_bridge() handle non PCIE VFs well

2013-01-09 Thread Don Dutile

On 01/09/2013 05:27 AM, Tadeusz Struk wrote:

On 01/08/2013 05:05 PM, Don Dutile wrote:


(a) no such thing as a non-PCIe VF -- all VFs
 are PCIe-based.


The sriov spec says that a VF doesn't necessarily has to have PCIE cap:
"3.5 PCI Express Capability:
...
PFs and VFs are required to implement this capability ... subject to
the exceptions and additional requirements described below"


(b) code says to return null if VF doesn't have PCIe cap,
 but the code checks if pdev is VF and if PF is PCIe,
 which it must be! ...


You are right, I should rather check if the VF is not a pcie.


Again -- nack! -- SRIOV devices must be PCIe.
Virtualization support expects VFs to be PCIe-based,
and supports things like:
(a) FLR
(b) dev-id tagged source packetting for DMA/IOMMU-mapping/filtering
(c) MSI/MSI-X only
 etc


nack until a better&/or matching explanation of what
the real problem is, and what the solution is trying to do.


The problem is that I do have a device where VFs are not PCIE and I get this 
nasty warning.
For now I have a workaround, but it would be nice it Linux would support non 
PCIE VFs.


This is a violation of the SRIOV spec.
I do not see how we'll take a patch for violating a core specification,
and then expecting us to hack the core sriov support for it.
At best, a quirk-like hack would be entertained.

Why is this call needed by your VF (or PF) driver ?


Thanks,
T



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Re: [PATCH] PCI: Make pci_find_upstream_pcie_bridge() handle non PCIE VFs well

2013-01-09 Thread Tadeusz Struk
On 01/08/2013 05:05 PM, Don Dutile wrote:

> (a) no such thing as a non-PCIe VF -- all VFs
> are PCIe-based.

The sriov spec says that a VF doesn't necessarily has to have PCIE cap:
"3.5 PCI Express Capability:
   ...
   PFs and VFs are required to implement this capability ... subject to
   the exceptions and additional requirements described below"

> (b) code says to return null if VF doesn't have PCIe cap,
> but the code checks if pdev is VF and if PF is PCIe,
> which it must be! ...

You are right, I should rather check if the VF is not a pcie.

> nack until a better &/or matching explanation of what
> the real problem is, and what the solution is trying to do.

The problem is that I do have a device where VFs are not PCIE and I get this 
nasty warning.
For now I have a workaround, but it would be nice it Linux would support non 
PCIE VFs.

Thanks,
T

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Re: [PATCH] PCI: Make pci_find_upstream_pcie_bridge() handle non PCIE VFs well

2013-01-09 Thread Tadeusz Struk
On 01/08/2013 05:05 PM, Don Dutile wrote:

 (a) no such thing as a non-PCIe VF -- all VFs
 are PCIe-based.

The sriov spec says that a VF doesn't necessarily has to have PCIE cap:
3.5 PCI Express Capability:
   ...
   PFs and VFs are required to implement this capability ... subject to
   the exceptions and additional requirements described below

 (b) code says to return null if VF doesn't have PCIe cap,
 but the code checks if pdev is VF and if PF is PCIe,
 which it must be! ...

You are right, I should rather check if the VF is not a pcie.

 nack until a better /or matching explanation of what
 the real problem is, and what the solution is trying to do.

The problem is that I do have a device where VFs are not PCIE and I get this 
nasty warning.
For now I have a workaround, but it would be nice it Linux would support non 
PCIE VFs.

Thanks,
T

--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
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Re: [PATCH] PCI: Make pci_find_upstream_pcie_bridge() handle non PCIE VFs well

2013-01-09 Thread Don Dutile

On 01/09/2013 05:27 AM, Tadeusz Struk wrote:

On 01/08/2013 05:05 PM, Don Dutile wrote:


(a) no such thing as a non-PCIe VF -- all VFs
 are PCIe-based.


The sriov spec says that a VF doesn't necessarily has to have PCIE cap:
3.5 PCI Express Capability:
...
PFs and VFs are required to implement this capability ... subject to
the exceptions and additional requirements described below


(b) code says to return null if VF doesn't have PCIe cap,
 but the code checks if pdev is VF and if PF is PCIe,
 which it must be! ...


You are right, I should rather check if the VF is not a pcie.


Again -- nack! -- SRIOV devices must be PCIe.
Virtualization support expects VFs to be PCIe-based,
and supports things like:
(a) FLR
(b) dev-id tagged source packetting for DMA/IOMMU-mapping/filtering
(c) MSI/MSI-X only
 etc


nack until a better/or matching explanation of what
the real problem is, and what the solution is trying to do.


The problem is that I do have a device where VFs are not PCIE and I get this 
nasty warning.
For now I have a workaround, but it would be nice it Linux would support non 
PCIE VFs.


This is a violation of the SRIOV spec.
I do not see how we'll take a patch for violating a core specification,
and then expecting us to hack the core sriov support for it.
At best, a quirk-like hack would be entertained.

Why is this call needed by your VF (or PF) driver ?


Thanks,
T



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Re: [PATCH] PCI: Make pci_find_upstream_pcie_bridge() handle non PCIE VFs well

2013-01-08 Thread Don Dutile

On 01/08/2013 09:32 AM, tadeusz.st...@intel.com wrote:

pci_find_upstream_pcie_bridge() doesn't handle well non PCIE VFs
that are part of a PCIE PF device.

Signed-off-by: Tadeusz Struk
---
  drivers/pci/search.c |6 ++
  1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/search.c b/drivers/pci/search.c
index bf969ba..8ecdab2 100644
--- a/drivers/pci/search.c
+++ b/drivers/pci/search.c
@@ -23,6 +23,8 @@ EXPORT_SYMBOL_GPL(pci_bus_sem);
   * if the device isn't connected to a PCIe bridge (that is its parent is a
   * legacy PCI bridge and the bridge is directly connected to bus 0), return 
its
   * parent
+ * if the device is a VF that doesn't have PCIe cap,
+ * but the PF is a PCIE, return NULL
   */
  struct pci_dev *
  pci_find_upstream_pcie_bridge(struct pci_dev *pdev)
@@ -31,6 +33,10 @@ pci_find_upstream_pcie_bridge(struct pci_dev *pdev)

if (pci_is_pcie(pdev))
return NULL;
+
+   if (pdev->is_virtfn&&  pci_is_pcie(pdev->physfn))
+   return NULL;
+
while (1) {
if (pci_is_root_bus(pdev->bus))
break;


The verbage/description is confusing, and
the comment doesn't match the code:
(a) no such thing as a non-PCIe VF -- all VFs
are PCIe-based.
(b) code says to return null if VF doesn't have PCIe cap,
but the code checks if pdev is VF and if PF is PCIe,
which it must be! ...

nack until a better &/or matching explanation of what
the real problem is, and what the solution is trying to do.

- Don

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Please read the FAQ at  http://www.tux.org/lkml/


[PATCH] PCI: Make pci_find_upstream_pcie_bridge() handle non PCIE VFs well

2013-01-08 Thread tadeusz . struk
pci_find_upstream_pcie_bridge() doesn't handle well non PCIE VFs
that are part of a PCIE PF device.

Signed-off-by: Tadeusz Struk 
---
 drivers/pci/search.c |6 ++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/search.c b/drivers/pci/search.c
index bf969ba..8ecdab2 100644
--- a/drivers/pci/search.c
+++ b/drivers/pci/search.c
@@ -23,6 +23,8 @@ EXPORT_SYMBOL_GPL(pci_bus_sem);
  * if the device isn't connected to a PCIe bridge (that is its parent is a
  * legacy PCI bridge and the bridge is directly connected to bus 0), return its
  * parent
+ * if the device is a VF that doesn't have PCIe cap,
+ * but the PF is a PCIE, return NULL
  */
 struct pci_dev *
 pci_find_upstream_pcie_bridge(struct pci_dev *pdev)
@@ -31,6 +33,10 @@ pci_find_upstream_pcie_bridge(struct pci_dev *pdev)
 
if (pci_is_pcie(pdev))
return NULL;
+
+   if (pdev->is_virtfn && pci_is_pcie(pdev->physfn))
+   return NULL;
+
while (1) {
if (pci_is_root_bus(pdev->bus))
break;
-- 
1.7.7

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[PATCH] PCI: Make pci_find_upstream_pcie_bridge() handle non PCIE VFs well

2013-01-08 Thread tadeusz . struk
pci_find_upstream_pcie_bridge() doesn't handle well non PCIE VFs
that are part of a PCIE PF device.

Signed-off-by: Tadeusz Struk tadeusz.st...@intel.com
---
 drivers/pci/search.c |6 ++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/search.c b/drivers/pci/search.c
index bf969ba..8ecdab2 100644
--- a/drivers/pci/search.c
+++ b/drivers/pci/search.c
@@ -23,6 +23,8 @@ EXPORT_SYMBOL_GPL(pci_bus_sem);
  * if the device isn't connected to a PCIe bridge (that is its parent is a
  * legacy PCI bridge and the bridge is directly connected to bus 0), return its
  * parent
+ * if the device is a VF that doesn't have PCIe cap,
+ * but the PF is a PCIE, return NULL
  */
 struct pci_dev *
 pci_find_upstream_pcie_bridge(struct pci_dev *pdev)
@@ -31,6 +33,10 @@ pci_find_upstream_pcie_bridge(struct pci_dev *pdev)
 
if (pci_is_pcie(pdev))
return NULL;
+
+   if (pdev-is_virtfn  pci_is_pcie(pdev-physfn))
+   return NULL;
+
while (1) {
if (pci_is_root_bus(pdev-bus))
break;
-- 
1.7.7

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Re: [PATCH] PCI: Make pci_find_upstream_pcie_bridge() handle non PCIE VFs well

2013-01-08 Thread Don Dutile

On 01/08/2013 09:32 AM, tadeusz.st...@intel.com wrote:

pci_find_upstream_pcie_bridge() doesn't handle well non PCIE VFs
that are part of a PCIE PF device.

Signed-off-by: Tadeusz Struktadeusz.st...@intel.com
---
  drivers/pci/search.c |6 ++
  1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/search.c b/drivers/pci/search.c
index bf969ba..8ecdab2 100644
--- a/drivers/pci/search.c
+++ b/drivers/pci/search.c
@@ -23,6 +23,8 @@ EXPORT_SYMBOL_GPL(pci_bus_sem);
   * if the device isn't connected to a PCIe bridge (that is its parent is a
   * legacy PCI bridge and the bridge is directly connected to bus 0), return 
its
   * parent
+ * if the device is a VF that doesn't have PCIe cap,
+ * but the PF is a PCIE, return NULL
   */
  struct pci_dev *
  pci_find_upstream_pcie_bridge(struct pci_dev *pdev)
@@ -31,6 +33,10 @@ pci_find_upstream_pcie_bridge(struct pci_dev *pdev)

if (pci_is_pcie(pdev))
return NULL;
+
+   if (pdev-is_virtfn  pci_is_pcie(pdev-physfn))
+   return NULL;
+
while (1) {
if (pci_is_root_bus(pdev-bus))
break;


The verbage/description is confusing, and
the comment doesn't match the code:
(a) no such thing as a non-PCIe VF -- all VFs
are PCIe-based.
(b) code says to return null if VF doesn't have PCIe cap,
but the code checks if pdev is VF and if PF is PCIe,
which it must be! ...

nack until a better /or matching explanation of what
the real problem is, and what the solution is trying to do.

- Don

--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/