This fixes a kernel crash on rmmod, in the case where the controller
was restarted before doing the rmmod.
Signed-off-by: Michael Buesch <mb@xxxxxxxxx>
---
Stefano, this is untested. Please test by doing
echo -n 1 >/debug/b43legacy/phy*/restart
rmmod b43legacy
It should not crash anymore at the rmmod (actually the restart should
also hang in b43legacy, as it has a deadlock, which this patch also fixes).
Index: wireless-testing/drivers/net/wireless/b43legacy/main.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/b43legacy/main.c 2008-05-15 23:31:37.000000000 +0200
+++ wireless-testing/drivers/net/wireless/b43legacy/main.c 2008-05-22 17:02:59.000000000 +0200
@@ -3035,13 +3035,12 @@ static void b43legacy_set_pretbtt(struct
}
/* Shutdown a wireless core */
/* Locking: wl->mutex */
static void b43legacy_wireless_core_exit(struct b43legacy_wldev *dev)
{
- struct b43legacy_wl *wl = dev->wl;
struct b43legacy_phy *phy = &dev->phy;
u32 macctl;
B43legacy_WARN_ON(b43legacy_status(dev) > B43legacy_STAT_INITIALIZED);
if (b43legacy_status(dev) != B43legacy_STAT_INITIALIZED)
return;
@@ -3050,18 +3049,12 @@ static void b43legacy_wireless_core_exit
/* Stop the microcode PSM. */
macctl = b43legacy_read32(dev, B43legacy_MMIO_MACCTL);
macctl &= ~B43legacy_MACCTL_PSM_RUN;
macctl |= B43legacy_MACCTL_PSM_JMP0;
b43legacy_write32(dev, B43legacy_MMIO_MACCTL, macctl);
- mutex_unlock(&wl->mutex);
- /* Must unlock as it would otherwise deadlock. No races here.
- * Cancel possibly pending workqueues. */
- cancel_work_sync(&dev->restart_work);
- mutex_lock(&wl->mutex);
-
b43legacy_leds_exit(dev);
b43legacy_rng_exit(dev->wl);
b43legacy_pio_free(dev);
b43legacy_dma_free(dev);
b43legacy_chip_exit(dev);
b43legacy_radio_turn_off(dev, 1);
@@ -3482,12 +3475,14 @@ static void b43legacy_chip_reset(struct
if (err) {
b43legacy_wireless_core_exit(dev);
goto out;
}
}
out:
+ if (err)
+ wl->current_dev = NULL; /* Failed to init the dev. */
mutex_unlock(&wl->mutex);
if (err)
b43legacyerr(wl, "Controller restart FAILED\n");
else
b43legacyinfo(wl, "Controller restarted\n");
}
@@ -3614,15 +3609,17 @@ err_powerdown:
static void b43legacy_one_core_detach(struct ssb_device *dev)
{
struct b43legacy_wldev *wldev;
struct b43legacy_wl *wl;
+ /* Do not cancel ieee80211-workqueue based work here.
+ * See comment in b43legacy_remove(). */
+
wldev = ssb_get_drvdata(dev);
wl = wldev->wl;
- cancel_work_sync(&wldev->restart_work);
b43legacy_debugfs_remove_device(wldev);
b43legacy_wireless_core_detach(wldev);
list_del(&wldev->list);
wl->nr_devs--;
ssb_set_drvdata(dev, NULL);
kfree(wldev);
@@ -3784,12 +3781,16 @@ err_wireless_exit:
static void b43legacy_remove(struct ssb_device *dev)
{
struct b43legacy_wl *wl = ssb_get_devtypedata(dev);
struct b43legacy_wldev *wldev = ssb_get_drvdata(dev);
+ /* We must cancel any work here before unregistering from ieee80211,
+ * as the ieee80211 unreg will destroy the workqueue. */
+ cancel_work_sync(&wldev->restart_work);
+
B43legacy_WARN_ON(!wl);
if (wl->current_dev == wldev)
ieee80211_unregister_hw(wl->hw);
b43legacy_one_core_detach(dev);
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
