> -----Original Message-----
> From: Dariusz Stojaczyk [mailto:darek.stojac...@gmail.com]
> Sent: Monday, November 5, 2018 10:40 PM
> To: dev@dpdk.org; gaetan.ri...@6wind.com
> Cc: Stojaczyk, Dariusz <dariusz.stojac...@intel.com>; Zhang, Qi Z
> <qi.z.zh...@intel.com>
> Subject: [PATCH v2] bus/pci: update device devargs on each rescan
>
> From: Darek Stojaczyk <dariusz.stojac...@intel.com>
>
> Bus rescan is done e.g. during the device hotplug, where devargs are
> re-allocated. By not updating the rte_device->devargs pointer we potentially
> make it a dangling one, as previous devargs could have been (or will be soon)
> freed.
Yes, this is the similar issue we met on vdev.
The key problem is we have rte_devargs_insert will destroy a devargs which is
still referenced by a rte_device
I'm thinking , why not just keep always keep a snapshot of devargs in
rte_device to make things simple?
We could introduce a API like rte_dev_assign_devargs(dev, devargs) which
handled the clone and destroy stuff and can be used for all buses.
If that idea is acceptable, I would prefer the issue in this patch could be
fixed in pci_name_set by clone a new copy as workaround.
>
> Fixes: 55e411b301c3 ("bus/pci: fix resource mapping override")
> Cc: qi.z.zh...@intel.com
>
> Signed-off-by: Darek Stojaczyk <dariusz.stojac...@intel.com>
> ---
> Changes since v1:
> * introduce additional pci_devargs_lookup() check to make
> the code slightly more readable (Gaetan Rivet)
>
> drivers/bus/pci/linux/pci.c | 5 +++++ drivers/bus/pci/pci_common.c |
> 3 ++-
> drivers/bus/pci/private.h | 11 +++++++++++
> 3 files changed, 18 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/bus/pci/linux/pci.c b/drivers/bus/pci/linux/pci.c index
> c99d523f0..a32d4848e 100644
> --- a/drivers/bus/pci/linux/pci.c
> +++ b/drivers/bus/pci/linux/pci.c
> @@ -379,6 +379,11 @@ pci_scan_one(const char *dirname, const struct
> rte_pci_addr *addr)
> RTE_LOG(ERR, EAL, "Unexpected
> device scan
> at %s!\n",
> filename);
> }
> +
> + if (pci_devargs_lookup(dev2) !=
> + dev2->device.devargs)
> + pci_name_set(dev2);
> +
> free(dev);
> }
> return 0;
> diff --git a/drivers/bus/pci/pci_common.c b/drivers/bus/pci/pci_common.c
> index 6276e5d69..fcaf76ed2 100644
> --- a/drivers/bus/pci/pci_common.c
> +++ b/drivers/bus/pci/pci_common.c
> @@ -42,7 +42,8 @@ const char *rte_pci_get_sysfs_path(void)
> return path;
> }
>
> -static struct rte_devargs *pci_devargs_lookup(struct rte_pci_device *dev)
> +struct rte_devargs *
> +pci_devargs_lookup(struct rte_pci_device *dev)
> {
> struct rte_devargs *devargs;
> struct rte_pci_addr addr;
> diff --git a/drivers/bus/pci/private.h b/drivers/bus/pci/private.h index
> 13c3324bb..8b2e904f0 100644
> --- a/drivers/bus/pci/private.h
> +++ b/drivers/bus/pci/private.h
> @@ -43,6 +43,17 @@ void
> pci_name_set(struct rte_pci_device *dev);
>
> /**
> + * Find matching up-to-date devargs for a given device.
> + *
> + * @param pci_dev
> + * PCI device
> + * @return
> + * A devargs pointer or NULL
> + */
> +struct rte_devargs *
> +pci_devargs_lookup(struct rte_pci_device *dev);
> +
> +/**
> * Add a PCI device to the PCI Bus (append to PCI Device list). This function
> * also updates the bus references of the PCI Device (and the generic device
> * object embedded within.
> --
> 2.11.0
