[PATCH] EDAC: protect memory controller list

- Fix code so we always hold mem_ctls_mutex while we are stepping
  through the list of mem_ctl_info structures.  Otherwise bad things
  may happen if one task is stepping through the list while another
  task is modifying it.  We may eventually want to use reference
  counting to manage the mem_ctl_info structures.  In the meantime we
  may as well fix this bug.

- Don't disable interrupts while we are walking the list of
  mem_ctl_info structures in check_mc_devices().  This is unnecessary.

Signed-off-by: David S. Peterson <dsp@llnl.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/edac/i82860_edac.c b/drivers/edac/i82860_edac.c
index 942129df0212..688854260a0e 100644
--- a/drivers/edac/i82860_edac.c
+++ b/drivers/edac/i82860_edac.c
@@ -237,9 +237,10 @@ static void __devexit i82860_remove_one(struct pci_dev *pdev)
 
         debugf0("%s()\n", __func__);
 
-        mci = edac_mc_find_mci_by_pdev(pdev);
-        if ((mci != NULL) && (edac_mc_del_mc(mci) == 0))
-                edac_mc_free(mci);
+        if ((mci = edac_mc_del_mc(pdev)) == NULL)
+                return;
+
+        edac_mc_free(mci);
 }
 
 static const struct pci_device_id i82860_pci_tbl[] __devinitdata = {