Re: current git crashes on bootup with pci_iounmap()

[Tejun Heo <htejun@gmail.com>]

Kay Sievers wrote:
> On 2/13/07, Kay Sievers <kay.sievers@vrfy.org> wrote:
>> On Tue, 2007-02-13 at 17:04 +0100, Marcel Holtmann wrote:
>> > > kernel BUG at lib/iomap.c:254!
>> > > invalid opcode: 0000 [#1]
>> > > ...
>> > >
>> > > The screen picture is here:
>> > >   http://vrfy.org/pci_iounmap.jpg
>> > >
>> > > It's a Thinkpad T43p.
>> > >
>> > > 2.6.20 was working fine.
>> > >
>> > > Commenting out:
>> > >   IO_COND(addr, /* nothing */, iounmap(addr));
>> > > in:
>> > >   lib/iomap.c:254
>> > > makes at least booting up possible.
>> >
>> > I saw a similar one on my X41. Disabling the AHCI driver made the
>> > machine booting again.
>>
>> Hey Marcel,
>> yeah, that works fine here too.
> 
> Tejun, Jeff, any ideas what's going wrong with the iomap change and
> the AHCI driver?

The following commit should have fixed the problem, at least the oops.
Care to give the current git head a shot?

commit fb4d64e78ceab77cf20f7796f74aa10ebe862032
Author: Frederik Deweerdt <deweerdt@free.fr>
Date:   Fri Feb 16 01:27:15 2007 -0800

    [PATCH] pci_iomap_regions() error handling fix

    It appears that the pcim_iomap_regions() function doesn't get the error
    handling right. It BUGs early at boot with a backtrace along the
lines of:

    ahci_init
    pci_register_driver
    driver_register
    [...]
    ahci_init_one
    pcim_iomap_region
    pcim_iounmap

    The following patch allows me to boot. Only the if(mask..) continue;
    part fixes the problem actually, the gotos where changed so that we
    don't try to unmap something we couldn't map anyway.

    Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com>
    Cc: Al Viro <viro@zeniv.linux.org.uk>
    Cc: Tejun Heo <htejun@gmail.com>
    Cc: Jeff Garzik <jeff@garzik.org>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

-- 
tejun