lkml.org 
[lkml]   [2010]   [Jan]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: mcs7830 usb net: "scheduling while atomic" danger?
    Date
    On Monday 18 January 2010, Julia Lawall wrote:
    > On Mon, 18 Jan 2010, Andreas Mohr wrote:
    > >
    > > Forgive me, but doesn't that mutex_lock()/msleep() (ab)use mean
    > > risking a "scheduling while atomic"?
    > > (such as discussed in e.g.
    > > http://search.luky.org/linux-kernel.2004/msg92817.html )
    > >
    > >
    > > And, if that is the case, shouldn't all such cases simply be killed for
    > > good via a capable semantic patch?
    >
    > The semantic match shown below finds 55 matches. All but two involve
    > mutex_lock. Those are in the file
    > /var/linuxes/linux-next/drivers/usb/host/ehci-hub.c
    > in the functions ehci_bus_suspend and ehci_hub_control.

    That code looks indeed broken as was added las July as part of 331ac6b288d9
    "USB: EHCI: Add Intel Moorestown EHCI controller HOSTPCx extensions and
    support phy low power mode". The reason that this hasn't triggered is
    probably the lack of Moorestown machines in the field.

    Arnd


    \
     
     \ /
      Last update: 2010-01-18 22:31    [W:0.042 / U:90.612 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site