lkml.org 
[lkml]   [2008]   [May]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH] USB: fix deadlock in HCD code

    >> > > Used in the suspend code. Your patch is indeed correct, but I fear
    >> > > there might be a second bug caused by wrong calling conditions.
    >> > The problem in the Novell bugzilla entry was caused by the fact that the
    >> > OHCI irq routine was invoked with interrupts enabled, owing to a missing
    >> > IRQF_DISABLED flag. That bug has already been fixed in 2.6.25.
    >>
    >> That indeed is 2.6.25 kernel. I guess you are talking about commit
    >> 442258e2ff69 here.
    >
    > Yes.
    >
    >> If so, the reporter is definitely using the kernel
    >> containing this commit, and the lockups still trigger.
    >>
    >> Seems that my patch is papering over the real bug (someone enabling
    >> interrupts somewhere) indeed, but I can't seem to be able to find such
    >> codepath.
    >
    > You could try testing the interrupt-enable flag at various places
    > in ohci-hcd (start with finish_urb) and printing an error message if
    > interrupts are enabled.
    >
    > One possibility is that in an earlier call to finish_urb,
    > usb_hcd_giveback_urb was called with interrupts disabled and returned
    > with interrupts enabled. In other words, some driver's callback
    > routine may have enabled interrupts incorrectly.

    Alan,

    I am trying your suggestion right now. Lets see if it finds something.

    Thanks,
    Leonardo



    \
     
     \ /
      Last update: 2008-05-21 21:55    [W:0.050 / U:0.296 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site