[dpdk-dev] [PATCH] pci/linux: copy new id for inserted device

[dpdk-dev] [PATCH] pci/linux: copy new id for inserted device

[Jim Harris]

When a device is inserted into an existing BDF slot
that has not been probed, we must overwrite the old
PCI ID with the ID of the new function. Otherwise
we may not probe the function with the correct driver,
if at all.

Signed-off-by: Jim Harris <james.r.harris@intel.com>
---
 drivers/bus/pci/linux/pci.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/bus/pci/linux/pci.c b/drivers/bus/pci/linux/pci.c
index a2198abf4..4701661e5 100644
--- a/drivers/bus/pci/linux/pci.c
+++ b/drivers/bus/pci/linux/pci.c
@@ -352,6 +352,7 @@ pci_scan_one(const char *dirname, const struct rte_pci_addr *addr)
 				if (!rte_dev_is_probed(&dev2->device)) {
 					dev2->kdrv = dev->kdrv;
 					dev2->max_vfs = dev->max_vfs;
+					memcpy(&dev2->id, &dev->id, sizeof(dev2->id));
 					pci_name_set(dev2);
 					memmove(dev2->mem_resource,
 						dev->mem_resource,
@@ -365,7 +366,8 @@ pci_scan_one(const char *dirname, const struct rte_pci_addr *addr)
 					 * need to do anything here unless...
 					 **/
 					if (dev2->kdrv != dev->kdrv ||
-						dev2->max_vfs != dev->max_vfs)
+						dev2->max_vfs != dev->max_vfs ||
+						memcmp(&dev2->id, &dev->id, sizeof(dev2->id))
 						/*
 						 * This should not happens.
 						 * But it is still possible if
-- 
2.20.1

[dpdk-dev] [PATCH v2] pci/linux: copy new id for inserted device

[Jim Harris]

When a device is inserted into an existing BDF slot
that has not been probed, we must overwrite the old
PCI ID with the ID of the new function. Otherwise
we may not probe the function with the correct driver,
if at all.

Signed-off-by: Jim Harris <james.r.harris@intel.com>
---
 drivers/bus/pci/linux/pci.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/bus/pci/linux/pci.c b/drivers/bus/pci/linux/pci.c
index a2198abf4..d8fd973b2 100644
--- a/drivers/bus/pci/linux/pci.c
+++ b/drivers/bus/pci/linux/pci.c
@@ -352,6 +352,7 @@ pci_scan_one(const char *dirname, const struct rte_pci_addr *addr)
 				if (!rte_dev_is_probed(&dev2->device)) {
 					dev2->kdrv = dev->kdrv;
 					dev2->max_vfs = dev->max_vfs;
+					memcpy(&dev2->id, &dev->id, sizeof(dev2->id));
 					pci_name_set(dev2);
 					memmove(dev2->mem_resource,
 						dev->mem_resource,
@@ -365,7 +366,8 @@ pci_scan_one(const char *dirname, const struct rte_pci_addr *addr)
 					 * need to do anything here unless...
 					 **/
 					if (dev2->kdrv != dev->kdrv ||
-						dev2->max_vfs != dev->max_vfs)
+						dev2->max_vfs != dev->max_vfs ||
+						memcmp(&dev2->id, &dev->id, sizeof(dev2->id)))
 						/*
 						 * This should not happens.
 						 * But it is still possible if
-- 
2.20.1

Re: [dpdk-dev] [PATCH v2] pci/linux: copy new id for inserted device

[Thomas Monjalon]

Hi Jim,

Sorry I see nobody reviewed your patch.

Jim Harris <james.r.harris@intel.com> wrote:
> + memcpy(&dev2->id, &dev->id, sizeof(dev2->id));
[...]
> + memcmp(&dev2->id, &dev->id, sizeof(dev2->id)))

Why using memcpy and memcmp instead of simple assignment and comparison?

Re: [dpdk-dev] [PATCH v2] pci/linux: copy new id for inserted device

[Harris, James R]

On 10/7/20, 8:06 AM, "Thomas Monjalon" <thomas@monjalon.net> wrote:

    Hi Jim,

    Sorry I see nobody reviewed your patch.

    Jim Harris <james.r.harris@intel.com> wrote:
    > + memcpy(&dev2->id, &dev->id, sizeof(dev2->id));
    [...]
    > + memcmp(&dev2->id, &dev->id, sizeof(dev2->id)))

    Why using memcpy and memcmp instead of simple assignment and comparison?

Direct assignment and comparison would work too.  I did see some similar cases though using memcpy for rte_pci_addr (which is similar to rte_pci_id) in linux/pci_uio.c and linux/pci_vfio.c.  It wasn't clear to me if direct assignment/comparison for structures was the norm for DPDK.

I'm happy to send a v2 with a direct assignment/comparison though if that is preferred.

-Jim

Re: [dpdk-dev] [PATCH v2] pci/linux: copy new id for inserted device

[Thomas Monjalon]

12/10/2020 22:58, Harris, James R:
> 
> On 10/7/20, 8:06 AM, "Thomas Monjalon" <thomas@monjalon.net> wrote:
> 
>     Hi Jim,
> 
>     Sorry I see nobody reviewed your patch.
> 
>     Jim Harris <james.r.harris@intel.com> wrote:
>     > + memcpy(&dev2->id, &dev->id, sizeof(dev2->id));
>     [...]
>     > + memcmp(&dev2->id, &dev->id, sizeof(dev2->id)))
> 
>     Why using memcpy and memcmp instead of simple assignment and comparison?
> 
> Direct assignment and comparison would work too.  I did see some similar cases though using memcpy for rte_pci_addr (which is similar to rte_pci_id) in linux/pci_uio.c and linux/pci_vfio.c.  It wasn't clear to me if direct assignment/comparison for structures was the norm for DPDK.
> 
> I'm happy to send a v2 with a direct assignment/comparison though if that is preferred.

Yes please, direct assignment is preferred.
Thanks

[dpdk-dev] [PATCH v3] pci/linux: copy new id for inserted device

[Jim Harris]

When a device is inserted into an existing BDF slot
that has not been probed, we must overwrite the old
PCI ID with the ID of the new function. Otherwise
we may not probe the function with the correct driver,
if at all.

Signed-off-by: Jim Harris <james.r.harris@intel.com>
---
 drivers/bus/pci/linux/pci.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/bus/pci/linux/pci.c b/drivers/bus/pci/linux/pci.c
index a2198abf4..2e37735c2 100644
--- a/drivers/bus/pci/linux/pci.c
+++ b/drivers/bus/pci/linux/pci.c
@@ -352,6 +352,7 @@ pci_scan_one(const char *dirname, const struct rte_pci_addr *addr)
 				if (!rte_dev_is_probed(&dev2->device)) {
 					dev2->kdrv = dev->kdrv;
 					dev2->max_vfs = dev->max_vfs;
+					dev2->id = dev->id;
 					pci_name_set(dev2);
 					memmove(dev2->mem_resource,
 						dev->mem_resource,
@@ -365,7 +366,8 @@ pci_scan_one(const char *dirname, const struct rte_pci_addr *addr)
 					 * need to do anything here unless...
 					 **/
 					if (dev2->kdrv != dev->kdrv ||
-						dev2->max_vfs != dev->max_vfs)
+						dev2->max_vfs != dev->max_vfs ||
+						dev2->id != dev->id)
 						/*
 						 * This should not happens.
 						 * But it is still possible if
-- 
2.20.1

Re: [dpdk-dev] [PATCH v3] pci/linux: copy new id for inserted device

[Thomas Monjalon]

13/10/2020 00:01, Jim Harris:
> When a device is inserted into an existing BDF slot
> that has not been probed, we must overwrite the old
> PCI ID with the ID of the new function. Otherwise
> we may not probe the function with the correct driver,
> if at all.
> 
> Signed-off-by: Jim Harris <james.r.harris@intel.com>
> ---
> --- a/drivers/bus/pci/linux/pci.c
> +++ b/drivers/bus/pci/linux/pci.c
> @@ -352,6 +352,7 @@ pci_scan_one(const char *dirname, const struct rte_pci_addr *addr)
>  				if (!rte_dev_is_probed(&dev2->device)) {
>  					dev2->kdrv = dev->kdrv;
>  					dev2->max_vfs = dev->max_vfs;
> +					dev2->id = dev->id;

This simple assignment looks nicer than memcpy.
Thanks for this change.

[...]
>  					if (dev2->kdrv != dev->kdrv ||
> -						dev2->max_vfs != dev->max_vfs)
> +						dev2->max_vfs != dev->max_vfs ||
> +						dev2->id != dev->id)

Unfortunately comparison of structs is not supported.
It seems your original memcmp is right.

[dpdk-dev] [PATCH v4] pci/linux: copy new id for inserted device

[Jim Harris]

When a device is inserted into an existing BDF slot
that has not been probed, we must overwrite the old
PCI ID with the ID of the new function. Otherwise
we may not probe the function with the correct driver,
if at all.

Signed-off-by: Jim Harris <james.r.harris@intel.com>
---
 drivers/bus/pci/linux/pci.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/bus/pci/linux/pci.c b/drivers/bus/pci/linux/pci.c
index a2198abf4..86e920d1c 100644
--- a/drivers/bus/pci/linux/pci.c
+++ b/drivers/bus/pci/linux/pci.c
@@ -352,6 +352,7 @@ pci_scan_one(const char *dirname, const struct rte_pci_addr *addr)
 				if (!rte_dev_is_probed(&dev2->device)) {
 					dev2->kdrv = dev->kdrv;
 					dev2->max_vfs = dev->max_vfs;
+					dev2->id = dev->id;
 					pci_name_set(dev2);
 					memmove(dev2->mem_resource,
 						dev->mem_resource,
@@ -365,7 +366,8 @@ pci_scan_one(const char *dirname, const struct rte_pci_addr *addr)
 					 * need to do anything here unless...
 					 **/
 					if (dev2->kdrv != dev->kdrv ||
-						dev2->max_vfs != dev->max_vfs)
+						dev2->max_vfs != dev->max_vfs ||
+						memcmp(&dev2->id, &dev->id))
 						/*
 						 * This should not happens.
 						 * But it is still possible if
-- 
2.20.1

[dpdk-dev] [PATCH v5] pci/linux: copy new id for inserted device

[Jim Harris]

When a device is inserted into an existing BDF slot
that has not been probed, we must overwrite the old
PCI ID with the ID of the new function. Otherwise
we may not probe the function with the correct driver,
if at all.

Signed-off-by: Jim Harris <james.r.harris@intel.com>
---
 drivers/bus/pci/linux/pci.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/bus/pci/linux/pci.c b/drivers/bus/pci/linux/pci.c
index a2198abf4..e51f9d756 100644
--- a/drivers/bus/pci/linux/pci.c
+++ b/drivers/bus/pci/linux/pci.c
@@ -352,6 +352,7 @@ pci_scan_one(const char *dirname, const struct rte_pci_addr *addr)
 				if (!rte_dev_is_probed(&dev2->device)) {
 					dev2->kdrv = dev->kdrv;
 					dev2->max_vfs = dev->max_vfs;
+					dev2->id = dev->id;
 					pci_name_set(dev2);
 					memmove(dev2->mem_resource,
 						dev->mem_resource,
@@ -365,7 +366,8 @@ pci_scan_one(const char *dirname, const struct rte_pci_addr *addr)
 					 * need to do anything here unless...
 					 **/
 					if (dev2->kdrv != dev->kdrv ||
-						dev2->max_vfs != dev->max_vfs)
+						dev2->max_vfs != dev->max_vfs ||
+						memcmp(&dev2->id, &dev->id, sizeof(dev2->id)))
 						/*
 						 * This should not happens.
 						 * But it is still possible if
-- 
2.20.1

Re: [dpdk-dev] [PATCH v5] pci/linux: copy new id for inserted device

[Thomas Monjalon]

13/10/2020 19:03, Jim Harris:
> When a device is inserted into an existing BDF slot
> that has not been probed, we must overwrite the old
> PCI ID with the ID of the new function. Otherwise
> we may not probe the function with the correct driver,
> if at all.
> 
> Signed-off-by: Jim Harris <james.r.harris@intel.com>

Applied, thanks