[dpdk-dev,v2] bus/pci: fix wrong intr_handle.type with uio_pci_generic
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Commit Message
For virtio legacy device, testpmd startup fails when using
uio_pci_generic. The issue is caused by invoking the function
pci_ioport_map. The right intr_handle.type is already set before
calling it, we should avoid overwriting the default value "RTE_
INTR_HANDLE_UNKNOWN" in it. Besides, the removal has no harm to
other cases since it already is set to this value (0) at init.
Fixes: 756ce64b1ecd ("eal: introduce PCI ioport API")
Cc: stable@dpdk.org
Signed-off-by: Zhiyong Yang <zhiyong.yang@intel.com>
---
Changes in V2:
1. reword the commit log.
2. remove the assignment operation which causes the issue.
drivers/bus/pci/linux/pci.c | 1 -
1 file changed, 1 deletion(-)
Comments
29/12/2017 08:55, Zhiyong Yang:
> For virtio legacy device, testpmd startup fails when using
> uio_pci_generic. The issue is caused by invoking the function
> pci_ioport_map. The right intr_handle.type is already set before
> calling it, we should avoid overwriting the default value "RTE_
> INTR_HANDLE_UNKNOWN" in it. Besides, the removal has no harm to
> other cases since it already is set to this value (0) at init.
To be more precise, it is set to 0 by a memset on the whole struct
during allocation in the scan function (pci_scan_one).
> --- a/drivers/bus/pci/linux/pci.c
> +++ b/drivers/bus/pci/linux/pci.c
> @@ -723,7 +723,6 @@ pci_ioport_map(struct rte_pci_device *dev, int bar __rte_unused,
> if (!found)
> return -1;
>
> - dev->intr_handle.type = RTE_INTR_HANDLE_UNKNOWN;
There is the same assignment in pci_vfio_map_resource_primary(),
pci_vfio_map_resource_secondary() and pci_uio_map_resource().
Please could you check why there is such assignments?
> -----Original Message-----
> From: Thomas Monjalon [mailto:thomas@monjalon.net]
> Sent: Friday, December 29, 2017 7:07 PM
> To: Yang, Zhiyong <zhiyong.yang@intel.com>
> Cc: dev@dpdk.org; Yigit, Ferruh <ferruh.yigit@intel.com>; stable@dpdk.org
> Subject: Re: [PATCH v2] bus/pci: fix wrong intr_handle.type with uio_pci_generic
>
> 29/12/2017 08:55, Zhiyong Yang:
> > For virtio legacy device, testpmd startup fails when using
> > uio_pci_generic. The issue is caused by invoking the function
> > pci_ioport_map. The right intr_handle.type is already set before
> > calling it, we should avoid overwriting the default value "RTE_
> > INTR_HANDLE_UNKNOWN" in it. Besides, the removal has no harm to other
> > cases since it already is set to this value (0) at init.
>
> To be more precise, it is set to 0 by a memset on the whole struct during
> allocation in the scan function (pci_scan_one).
Ok
>
> > --- a/drivers/bus/pci/linux/pci.c
> > +++ b/drivers/bus/pci/linux/pci.c
> > @@ -723,7 +723,6 @@ pci_ioport_map(struct rte_pci_device *dev, int bar
> __rte_unused,
> > if (!found)
> > return -1;
> >
> > - dev->intr_handle.type = RTE_INTR_HANDLE_UNKNOWN;
>
> There is the same assignment in pci_vfio_map_resource_primary(),
> pci_vfio_map_resource_secondary() and pci_uio_map_resource().
>
> Please could you check why there is such assignments?
Well, Let me check them later.
Thanks
Zhiyong
> -----Original Message-----
> From: Thomas Monjalon [mailto:thomas@monjalon.net]
> Sent: Friday, December 29, 2017 7:07 PM
> To: Yang, Zhiyong <zhiyong.yang@intel.com>
> Cc: dev@dpdk.org; Yigit, Ferruh <ferruh.yigit@intel.com>; stable@dpdk.org
> Subject: Re: [PATCH v2] bus/pci: fix wrong intr_handle.type with uio_pci_generic
>
> 29/12/2017 08:55, Zhiyong Yang:
> > For virtio legacy device, testpmd startup fails when using
> > uio_pci_generic. The issue is caused by invoking the function
> > pci_ioport_map. The right intr_handle.type is already set before
> > calling it, we should avoid overwriting the default value "RTE_
> > INTR_HANDLE_UNKNOWN" in it. Besides, the removal has no harm to other
> > cases since it already is set to this value (0) at init.
>
> To be more precise, it is set to 0 by a memset on the whole struct during
> allocation in the scan function (pci_scan_one).
>
> > --- a/drivers/bus/pci/linux/pci.c
> > +++ b/drivers/bus/pci/linux/pci.c
> > @@ -723,7 +723,6 @@ pci_ioport_map(struct rte_pci_device *dev, int bar
> __rte_unused,
> > if (!found)
> > return -1;
> >
> > - dev->intr_handle.type = RTE_INTR_HANDLE_UNKNOWN;
>
> There is the same assignment in pci_vfio_map_resource_primary(),
> pci_vfio_map_resource_secondary() and pci_uio_map_resource().
>
> Please could you check why there is such assignments?
In general, the operation in the three functions intends to initialize the "intr_handle.type",
For example,
For pci_uio_map_resource(), it wants to get "unknown" status once the code returns abnormally after initializing.
If the code goes smoothly, dev->intr_handle.type must be assigned to "RTE_INTR_HANDLE_UIO" for bsd environment,
Or must be assigned to "RTE_INTR_HANDLE_UIO" or " RTE_INTR_HANDLE_UIO_INTX" for linux environment
In consideration of the "memset" in pci_scan_one, it can be removed to has no harm to the existing logic.
Of course, keeping it is ok.
pci_vfio_map_resource_primary() and pci_vfio_map_resource_secondary() are similar.
The author was emphasizing that intr_handle.type should be initialized (0) and can be assigned to a right value after it.
Once fails, we can read a status "unknown". I guess.
Turn back to the patch, it is crude to assign "unknown" directly since pci_ioport_map is not only used by real "unknown"
But also is used to handle uio_pci_generic driver on X86 platform. It is a special case to cause error for uio_pci_generic.
Thanks
Zhiyong
03/01/2018 04:29, Yang, Zhiyong:
> From: Thomas Monjalon [mailto:thomas@monjalon.net]
> > 29/12/2017 08:55, Zhiyong Yang:
> > > --- a/drivers/bus/pci/linux/pci.c
> > > +++ b/drivers/bus/pci/linux/pci.c
> > > @@ -723,7 +723,6 @@ pci_ioport_map(struct rte_pci_device *dev, int bar
> > __rte_unused,
> > > if (!found)
> > > return -1;
> > >
> > > - dev->intr_handle.type = RTE_INTR_HANDLE_UNKNOWN;
> >
> > There is the same assignment in pci_vfio_map_resource_primary(),
> > pci_vfio_map_resource_secondary() and pci_uio_map_resource().
> >
> > Please could you check why there is such assignments?
>
> In general, the operation in the three functions intends to initialize the "intr_handle.type",
> For example,
> For pci_uio_map_resource(), it wants to get "unknown" status once the code returns abnormally after initializing.
> If the code goes smoothly, dev->intr_handle.type must be assigned to "RTE_INTR_HANDLE_UIO" for bsd environment,
> Or must be assigned to "RTE_INTR_HANDLE_UIO" or " RTE_INTR_HANDLE_UIO_INTX" for linux environment
> In consideration of the "memset" in pci_scan_one, it can be removed to has no harm to the existing logic.
So what do you think of doing a v3 which removes it everywhere?
It would remove inconsistencies and avoid future questions.
> Of course, keeping it is ok.
>
> pci_vfio_map_resource_primary() and pci_vfio_map_resource_secondary() are similar.
>
> The author was emphasizing that intr_handle.type should be initialized (0) and can be assigned to a right value after it.
> Once fails, we can read a status "unknown". I guess.
>
> Turn back to the patch, it is crude to assign "unknown" directly since pci_ioport_map is not only used by real "unknown"
> But also is used to handle uio_pci_generic driver on X86 platform. It is a special case to cause error for uio_pci_generic.
> -----Original Message-----
> From: Thomas Monjalon [mailto:thomas@monjalon.net]
> Sent: Tuesday, January 9, 2018 11:34 PM
> To: Yang, Zhiyong <zhiyong.yang@intel.com>
> Cc: dev@dpdk.org; Yigit, Ferruh <ferruh.yigit@intel.com>
> Subject: Re: [dpdk-dev] [PATCH v2] bus/pci: fix wrong intr_handle.type with
> uio_pci_generic
>
> 03/01/2018 04:29, Yang, Zhiyong:
> > From: Thomas Monjalon [mailto:thomas@monjalon.net]
> > > 29/12/2017 08:55, Zhiyong Yang:
> > > > --- a/drivers/bus/pci/linux/pci.c
> > > > +++ b/drivers/bus/pci/linux/pci.c
> > > > @@ -723,7 +723,6 @@ pci_ioport_map(struct rte_pci_device *dev, int
> > > > bar
> > > __rte_unused,
> > > > if (!found)
> > > > return -1;
> > > >
> > > > - dev->intr_handle.type = RTE_INTR_HANDLE_UNKNOWN;
> > >
> > > There is the same assignment in pci_vfio_map_resource_primary(),
> > > pci_vfio_map_resource_secondary() and pci_uio_map_resource().
> > >
> > > Please could you check why there is such assignments?
> >
> > In general, the operation in the three functions intends to initialize
> > the "intr_handle.type", For example, For pci_uio_map_resource(), it
> > wants to get "unknown" status once the code returns abnormally after
> initializing.
> > If the code goes smoothly, dev->intr_handle.type must be assigned to
> > "RTE_INTR_HANDLE_UIO" for bsd environment, Or must be assigned to
> > "RTE_INTR_HANDLE_UIO" or " RTE_INTR_HANDLE_UIO_INTX" for linux
> environment In consideration of the "memset" in pci_scan_one, it can be
> removed to has no harm to the existing logic.
>
> So what do you think of doing a v3 which removes it everywhere?
> It would remove inconsistencies and avoid future questions.
>
It's reasonable and I will do that in V3.
Thanks
Zhiyong
@@ -723,7 +723,6 @@ pci_ioport_map(struct rte_pci_device *dev, int bar __rte_unused,
if (!found)
return -1;
- dev->intr_handle.type = RTE_INTR_HANDLE_UNKNOWN;
p->base = start;
RTE_LOG(DEBUG, EAL, "PCI Port IO found start=0x%x\n", start);