From a2f10d4a3069fee666dab20fab5458757ba1f22d Mon Sep 17 00:00:00 2001
From: Christian Gmeiner <christian.gmeiner@gmail.com>
Date: Fri, 25 Oct 2019 12:39:10 +0200
Subject: drm/etnaviv: fix dumping of iommuv2
Git-commit: a2f10d4a3069fee666dab20fab5458757ba1f22d
Patch-mainline: v5.4-rc6
References: bsc#1114279

etnaviv_iommuv2_dump_size(..) returns the number of PTE * SZ_4K but
etnaviv_iommuv2_dump(..) increments buf pointer even if there is no PTE.
This results in a bad buf pointer which gets used for memcpy(..), when
copying the MMU state in the coredump buffer.

Fixes: afb7b3b1deb4 ("drm/etnaviv: implement IOMMUv2 translation")
Cc: stable@vger.kernel.org
Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/etnaviv/etnaviv_iommu_v2.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/etnaviv/etnaviv_iommu_v2.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_iommu_v2.c
@@ -225,9 +225,11 @@ static void etnaviv_iommuv2_dump(struct
 
 	memcpy(buf, etnaviv_domain->mtlb_cpu, SZ_4K);
 	buf += SZ_4K;
-	for (i = 0; i < MMUv2_MAX_STLB_ENTRIES; i++, buf += SZ_4K)
-		if (etnaviv_domain->mtlb_cpu[i] & MMUv2_PTE_PRESENT)
+	for (i = 0; i < MMUv2_MAX_STLB_ENTRIES; i++)
+		if (etnaviv_domain->mtlb_cpu[i] & MMUv2_PTE_PRESENT) {
 			memcpy(buf, etnaviv_domain->stlb_cpu[i], SZ_4K);
+			buf += SZ_4K;
+		}
 }
 
 static void etnaviv_iommuv2_restore_nonsec(struct etnaviv_gpu *gpu)