EDAC, altera: Disable IRQs while injecting SDRAM errors

Disable IRQs while injecting SDRAM errors. The RT patches exposed
a spinlock deadlock where the spinlock taken for the regmap write
deadlocked with the IRQ clear regmap write.

Error injection is not normally enabled for ECC but only for testing.

Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1476906827-9412-1-git-send-email-tthayer@opensource.altera.com
Signed-off-by: Borislav Petkov <bp@suse.de>

diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
index 58d3e2b39b5b56c6a0594ab10a7dcce864ea5293..6421cc3c7dc1344a22cdaa6ed929e2aa940d0211 100644 (file)
--- a/drivers/edac/altera_edac.c
+++ b/drivers/edac/altera_edac.c
@@ -153,13 +153,17 @@ static ssize_t altr_sdr_mc_err_inject_write(struct file *file,
        if (count == 3) {
                edac_printk(KERN_ALERT, EDAC_MC,
                            "Inject Double bit error\n");
+               local_irq_disable();
                regmap_write(drvdata->mc_vbase, priv->ce_ue_trgr_offset,
                             (read_reg | priv->ue_set_mask));
+               local_irq_enable();
        } else {
                edac_printk(KERN_ALERT, EDAC_MC,
                            "Inject Single bit error\n");
+               local_irq_disable();
                regmap_write(drvdata->mc_vbase, priv->ce_ue_trgr_offset,
                             (read_reg | priv->ce_set_mask));
+               local_irq_enable();
        }
 
        ptemp[0] = 0x5A5A5A5A;