Re: [dpdk-dev] [PATCH] pci: properly parse 32-bit domain numbers

[Stephen Hemminger <stephen@networkplumber.org>]

On Tue, May 12, 2020 at 3:30 pm, Darek Stojaczyk 
<dariusz.stojaczyk@intel.com> wrote:
> The parsing code was bailing on domains greater than UINT16_MAX,
> but domain numbers like that are still valid and present on some 
> systems.
> One example is Intel VMD (Volume Management Device), which acts 
> somewhat
> as a software-managed PCI switch and its upstream linux driver assigns
> all downstream devices a PCI domain of 0x10000.
> 
> Parsing a BDF like 10000:01:00.0 was failing before. To fix it, 
> increase
> the upper limit of domain number to UINT32_MAX. This matches the size 
> of
> struct rte_pci_addr->domain (uint32).
> 
> Signed-off-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com 
> <mailto:dariusz.stojaczyk@intel.com>>
> ---
>  lib/librte_pci/rte_pci.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/librte_pci/rte_pci.c b/lib/librte_pci/rte_pci.c
> index d1ab6b414d..ad2cdfebb2 100644
> --- a/lib/librte_pci/rte_pci.c
> +++ b/lib/librte_pci/rte_pci.c
> @@ -72,9 +72,9 @@ pci_dbdf_parse(const char *input, struct 
> rte_pci_addr *dev_addr)
> 
>  	errno = 0;
>  	val = strtoul(in, &end, 16);
> -	if (errno != 0 || end[0] != ':' || val > UINT16_MAX)
> +	if (errno != 0 || end[0] != ':' || val > UINT32_MAX)
>  		return -EINVAL;
> -	dev_addr->domain = (uint16_t)val;
> +	dev_addr->domain = (uint32_t)val;
>  	in = end + 1;
>  	in = get_u8_pciaddr_field(in, &dev_addr->bus, ':');
>  	if (in == NULL)
> --
> 2.17.1


Agree this came up before on Hyper-V as well. It meant fixing libpci.

Not sure the cast of val is necessary, other than an attempt to silence 
some static checker
about implicit type conversion causing loss of precision.


>