From ea62c7b1bf6a7fa765bddfc710a279e233ead67c Mon Sep 17 00:00:00 2001
From: Thor Thayer <tthayer@opensource.altera.com>
Date: Wed, 19 Oct 2016 14:53:47 -0500
Subject: [PATCH 070/103] 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>
---
 drivers/edac/altera_edac.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/edac/altera_edac.c
+++ b/drivers/edac/altera_edac.c
@@ -153,13 +153,17 @@ static ssize_t altr_sdr_mc_err_inject_wr
 	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;