From: Eric Saint-Etienne <eric.saint.etienne@oracle.com>
Date: Mon, 30 Jan 2017 12:27:49 +0000 (-0800)
Subject: sparc64: fix for user probes in high memory
X-Git-Tag: v4.1.12-92~1^2~11
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=116582842126dbdf222efe29c2e4fc423c2fcd9e;p=users%2Fjedix%2Flinux-maple.git

sparc64: fix for user probes in high memory

Orabug 25428066

When returning from the user probe code into userspace process, PC & NPC are
truncated to 32 bits.

As a result of shared libraries get loaded very high in the virtual address
space of the process, placing a user probe inside a shared library makes the
kernel return into the process at the wrong address, causing it to seg'fault
most of the time.

This patch prevents truncating PC and NPC.

Signed-off-by: Eric Saint Etienne <eric.saint.etienne@oracle.com>
Reviewed-by: David Aldridge <david.j.aldridge@oracle.com>
Signed-off-by: Allen Pais <allen.pais@oracle.com>
---

diff --git a/arch/sparc/include/asm/uprobes.h b/arch/sparc/include/asm/uprobes.h
index f87aae5a908e6..36196c17aff8e 100644
--- a/arch/sparc/include/asm/uprobes.h
+++ b/arch/sparc/include/asm/uprobes.h
@@ -42,8 +42,8 @@ struct arch_uprobe {
 };
 
 struct arch_uprobe_task {
-	u32 saved_tpc;
-	u32 saved_tnpc;
+	u64 saved_tpc;
+	u64 saved_tnpc;
 };
 
 struct task_struct;