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Date: Sun, 15 Jun 2003 16:07:29 +0100
From: Russell King <rmk@arm.linux.org.uk>
To: Linux Kernel List <linux-kernel@vger.kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Subject: bad: scheduling while atomic! (Part Deux)
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	David Woodhouse <dwmw2@infradead.org>
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Sigh.  Another MTD deadlock, and cause of scheduling badness on UP preempt.

David, I think MTD needs an audit to ensure that no further cases exist.

static void cfi_intelext_sync (struct mtd_info *mtd)
{
        for (i=0; !ret && i<cfi->numchips; i++) {
                chip = &cfi->chips[i];

                spin_lock(chip->mutex);
                ret = get_chip(map, chip, chip->start, FL_SYNCING);
...
        }

        /* Unlock the chips again */

        for (i--; i >=0; i--) {
                chip = &cfi->chips[i];

                spin_lock(chip->mutex);
...
                spin_unlock(chip->mutex);
        }
}

-- 
Russell King (rmk@arm.linux.org.uk)                The developer of ARM Linux
             http://www.arm.linux.org.uk/personal/aboutme.html