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    SubjectRe: [BUG] pnpbios breaks floppy support
    Quoting Robert Hancock <>:

    > Philippe De Muyter wrote:
    >> On Sun, Feb 01, 2009 at 01:08:33AM -0600, Robert Hancock wrote:
    >>> Philippe De Muyter wrote:
    >>>> Hello linux experts,
    >>>> Today I tried to upgrade a PC's kernel from 2.6.11 to 2.6.22, and
    >>>> I saw some strange messages when booting :
    >>>> Floppy drive(s): fd0 is 1.44M
    >>>> floppy0: Floppy io-port 0x03f2 in use
    >>>> Previously, I had :
    >>>> Floppy drive(s): fd0 is 1.44M
    >>>> FDC 0 is a post-1991 82077
    >>>> Needless to say, my floppy hardware works perfectly, and my floppy
    >>>> was usable with the old kernel, while the floppy is now inaccessible
    >>>> with the new kernel. Even /dev/fd0 does not exist anymore.
    >>>> Searching for a cause to that problem, I saw the following messages
    >>>> before the floppy probe in the new kernel :
    >>>> PnPBIOS: Scanning system for PnP BIOS support...
    >>>> PnPBIOS: Found PnP BIOS installation structure at 0xc00fd5e0
    >>>> PnPBIOS: PnP BIOS version 1.0, entry 0xf0000:0x5ba3, dseg 0xf0000
    >>>> PnPBIOS: 17 nodes reported by PnP BIOS; 17 recorded by driver
    >>>> [...]
    >>>> pnp: 00:07: ioport range 0x3f0-0x3f1 has been reserved
    >>>> pnp: 00:07: ioport range 0x3f3-0x3f3 has been reserved
    >>>> [...]
    >>>> Searching the web and the outdated pnp kernel documentation, I
    >>>> finally found an option to add to my kernel parameters line :
    >>>> pnpbios=off
    >>>> Now my floppy works again, but I am not really satisfied.
    >>>> What do I loose with the 'pnpbios=off' option ?
    >>>> Isn't there a smoother option to allow pnpbios but avoiding to reserve
    >>>> floppy's io-ports ?
    >>>> Should I modify rather /drivers/block/floppy.c or /drivers/pnp/*.c
    >>>> to make pnpbios and floppy driver coexist peacefully ? And is there
    >>>> an example of such modifications for other standard peripherals ?
    >>> Presumably the problem is that your BIOS marks the IO ports used by
    >>> the floppy controller as reserved which prevents the floppy driver
    >>> from binding to them. (2.6.11 probably was before we even processed
    >>> PnP reserved regions.)
    >>> I think we now have handling for the case where the reservations
    >>> overlap PCI devices, but I think it's the first I've heard of them
    >>> overlapping the floppy IO ports..
    >> I should have added that, when started with pnpbios enabled, I have
    >> found the following in /sys/devices/pnp0/ :
    >> $ cat 00:03/id
    >> PNP0700
    >> $ cat 00:03/resources state = active
    >> io 0x3f4-0x3f5
    >> io 0x3f2-0x3f2
    >> irq 6
    >> dma 2
    >> $ cat 00:03/options
    >> port 0x3f4-0x3f4, align 0x0, size 0x2, 16-bit address decoding
    >> port 0x3f2-0x3f2, align 0x0, size 0x1, 16-bit address decoding
    >> irq 6 High-Edge
    >> dma 2 8-bit compatible
    >> AFAIK, PNP0700 is the pnp id for the standard floppy disk,
    >> and the resources and options files describe the expected io-ports
    >> of the floppy disk, so this does not seem to be an error in the bios.
    > There's likely another resource with id of PNP0C01 or PNP0C02
    > (Motherboard resources) which contains that same IO port range.

    Yes, could you post the same information for 00:07 so we can start to narrow
    this down? Also having "cat /proc/ioports" couldn't hurt.


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