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Date:   Fri, 21 Jan 2022 17:11:47 +0100
From:   Pali =?utf-8?B?Um9ow6Fy?= <pali@kernel.org>
To:     Martin =?utf-8?B?TWFyZcWh?= <mj@ucw.cz>
Cc:     Bjorn Helgaas <helgaas@kernel.org>,
        Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= <kw@linux.com>,
        Matthew Wilcox <willy@infradead.org>, linux-pci@vger.kernel.org
Subject: Re: [PATCH pciutils 3/5] libpci: generic: Implement SUBSYS also for
 PCI_HEADER_TYPE_BRIDGE
Message-ID: <20220121161147.n6byckl4rnezfgy6@pali>
References: <20220121135718.27172-1-pali@kernel.org>
 <20220121135718.27172-4-pali@kernel.org>
 <mj+md-20220121.144016.17855.nikam@ucw.cz>
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On Friday 21 January 2022 15:40:49 Martin Mareš wrote:
> Hello!
> 
> > +        case PCI_HEADER_TYPE_BRIDGE:
> > +          if (pci_read_word(d, PCI_STATUS) & PCI_STATUS_CAP_LIST)
> > +            {
> > +              byte been_there[256];
> > +              int where, id;
> > +
> > +              memset(been_there, 0, 256);
> > +              where = pci_read_byte(d, PCI_CAPABILITY_LIST) & ~3;
> > +              while (where && !been_there[where]++)
> 
> Please don't. There should be a single implementation of capability list
> walking in libpci, not everybody doing his own.

Current libpci code which walks capability list is in functions
pci_scan_caps() and pci_find_cap(). But pci_find_cap() calls
pci_fill_info() (only with PCI_FILL_CAPS flag). So I'm not sure if it is
a good idea to call pci_find_cap() from pci_generic_fill_info().