Commit 269d8523 authored Feb 06, 2017 by Eric Saint Etienne Committed by David S. Miller Feb 23, 2017

sparc64: fix for user probes in high memory



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

Due to shared libraries getting 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: David S. Miller <davem@davemloft.net>

parent fc5e8c28

arch/sparc/include/asm/uprobes.h

+2 −2

Original line number	Diff line number	Diff line
		@@ -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;