svn commit: r331952 - stable/11/sys/cddl/dev/fbt/arm

[Oleksandr Tymoshenko]

Author: gonzo
Date: Tue Apr  3 21:22:43 2018
New Revision: 331952
URL: https://svnweb.freebsd.org/changeset/base/331952

Log:
  MFC r312378 by andrew:
  
  Use the kernel stack in the ARM FBT DTrace provider. This is used to find
  the fifth argument to functions being traced, however there was an error
  where the userspace stack was being used. This may be invalid leading to
  a kernel panic if this address is unmapped.
  
  Submitted by:	Graeme Jenkinson <graeme.jenkinson at cl.cam.ac.uk>
  Differential Revision:	https://reviews.freebsd.org/D9229
  
  MFC commit fields
  PR:		211389

Modified:
  stable/11/sys/cddl/dev/fbt/arm/fbt_isa.c
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/sys/cddl/dev/fbt/arm/fbt_isa.c
==============================================================================
--- stable/11/sys/cddl/dev/fbt/arm/fbt_isa.c	Tue Apr  3 21:17:19 2018	(r331951)
+++ stable/11/sys/cddl/dev/fbt/arm/fbt_isa.c	Tue Apr  3 21:22:43 2018	(r331952)
@@ -61,7 +61,7 @@ fbt_invop(uintptr_t addr, struct trapframe *frame, uin
 
 			/* Get 5th parameter from stack */
 			DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
-			fifthparam = *(register_t *)frame->tf_usr_sp;
+			fifthparam = *(register_t *)frame->tf_svc_sp;
 			DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT | CPU_DTRACE_BADADDR);
 
 			dtrace_probe(fbt->fbtp_id, frame->tf_r0,