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    SubjectRe: [PATCH 2/2] cciss: Fix SCSI device reset handler
    On Tue, Jun 02 2009, Andrew Morton wrote:
    > On Tue, 2 Jun 2009 14:50:11 +0200
    > Jens Axboe <jens.axboe@oracle.com> wrote:
    >
    > > On Fri, May 29 2009, Andrew Morton wrote:
    > > > On Wed, 27 May 2009 15:30:07 -0500
    > > > scameron@beardog.cca.cpqcorp.net wrote:
    > > >
    > > > > +static int wait_for_device_to_become_ready(ctlr_info_t *h,
    > > > > + unsigned char lunaddr[])
    > > > > +{
    > > > > + int rc;
    > > > > + int count = 0;
    > > > > + int waittime = HZ;
    > > > > + CommandList_struct *c;
    > > > > +
    > > > > + c = cmd_alloc(h, 1);
    > > > > + if (!c) {
    > > > > + printk(KERN_WARNING "cciss%d: out of memory in "
    > > > > + "wait_for_device_to_become_ready.\n", h->ctlr);
    > > > > + return IO_ERROR;
    > > > > + }
    > > > > +
    > > > > + /* Send test unit ready until device ready, or give up. */
    > > > > + while (count < 20) {
    > > > > +
    > > > > + /* Wait for a bit. do this first, because if we send
    > > > > + * the TUR right away, the reset will just abort it.
    > > > > + */
    > > > > + set_current_state(TASK_INTERRUPTIBLE);
    > > > > + schedule_timeout(waittime);
    > > >
    > > > That's schedule_timeout_interruptible().
    > > >
    > > > The problem with interruptible sleeps of this nature is that they are
    > > > no-ops if the calling process happens to have signal_pending(). I
    > > > suspect that this condition will break your driver.
    > > >
    > > > If so, switching to schedule_timeout_uninterruptible() will unbreak it.
    > >
    > > I added Stephens patch and your fixup.
    >
    > My cciss-fix-scsi-device-reset-handler-fix.patch was a simple cleanup -
    > it uses schedule_timeout_interruptible().
    >
    > I believe that this should be changed to
    > schedule_timeout_uninterruptible() for the above reasons, but the cciss
    > guys fell asleep on me.

    It's an improvement, none the less. And I bet it should just be
    uninterruptible sleep, unless it has a good reason to accept signals.
    Mike? Stephen?

    --
    Jens Axboe



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