From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Date: Tue, 15 Nov 2016 15:06:06 +0000 (+0530)
Subject: powerpc/mm/coproc: Handle bad address on coproc slb fault
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=64168f4296fa507ba059307984cddcf957a81d5f;p=linux-beck.git

powerpc/mm/coproc: Handle bad address on coproc slb fault

VSID 0 is bad address. Don't create slb entries on coproc fault for
bad address

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---

diff --git a/arch/powerpc/mm/copro_fault.c b/arch/powerpc/mm/copro_fault.c
index 362954f98029..aaa7ec6788b9 100644
--- a/arch/powerpc/mm/copro_fault.c
+++ b/arch/powerpc/mm/copro_fault.c
@@ -134,6 +134,9 @@ int copro_calculate_slb(struct mm_struct *mm, u64 ea, struct copro_slb *slb)
 		pr_debug("%s: invalid region access at %016llx\n", __func__, ea);
 		return 1;
 	}
+	/* Bad address */
+	if (!vsid)
+		return 1;
 
 	vsid = (vsid << slb_vsid_shift(ssize)) | vsidkey;