svn commit: r322760 - stable/11/sys/arm64/arm64

[John Baldwin]

Author: jhb
Date: Mon Aug 21 17:29:37 2017
New Revision: 322760
URL: https://svnweb.freebsd.org/changeset/base/322760

Log:
  MFC 322436: Don't panic for PT_GETFPREGS.
  
  Only fetch the VFP state from the CPU if the thread whose registers are
  being requested is the current thread.  If a stopped thread's registers
  are being fetched by a debugger, the saved state in the PCB is already
  valid.

Modified:
  stable/11/sys/arm64/arm64/machdep.c
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/sys/arm64/arm64/machdep.c
==============================================================================
--- stable/11/sys/arm64/arm64/machdep.c	Mon Aug 21 17:20:31 2017	(r322759)
+++ stable/11/sys/arm64/arm64/machdep.c	Mon Aug 21 17:29:37 2017	(r322760)
@@ -213,7 +213,8 @@ fill_fpregs(struct thread *td, struct fpreg *regs)
 		 * If we have just been running VFP instructions we will
 		 * need to save the state to memcpy it below.
 		 */
-		vfp_save_state(td, pcb);
+		if (td == curthread)
+			vfp_save_state(td, pcb);
 
 		memcpy(regs->fp_q, pcb->pcb_vfp, sizeof(regs->fp_q));
 		regs->fp_cr = pcb->pcb_fpcr;