Re: port-pmax/52871: ptrace: fpregs panic on pmax

[David Holland <dholland-bugs%netbsd.org@localhost>]

The following reply was made to PR port-pmax/52871; it has been noted by GNATS.

From: David Holland <dholland-bugs%netbsd.org@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: port-pmax/52871: ptrace: fpregs panic on pmax
Date: Thu, 28 Dec 2017 11:18:56 +0000

 On Thu, Dec 28, 2017 at 09:55:00AM +0000, Kamil Rytarowski wrote:
  >    status=3D0x8ff34, cause=3D0x8, epc=3D0x800580dc, vaddr=3D0x84
  >    tf=3D0x80b038b0 ksp=3D0x80b03950 ra=3D0x8036799c ppl=3D0x8054cee0
  >    kernel: TLB miss (load or instr. fetch) trap
  >    Stopped in pid 18518.1 (t_ptrace_wait) at
  >  netbsd:process_read_fpregs+0x14:
  >            lw      v1,0(a2)
 
 Here's the problem:
 
 (1) sys_ptrace_common.c:1333:
         typedef int (*regfunc_t)(struct lwp *, void *);
 
 (2) sys_ptrace_common.c:1431:
         r = (regfunc_t)process_read_fpregs;
 
 (3) mips/process_machdep.c:136:
   int
   process_read_fpregs(struct lwp *l, struct fpreg *regs, size_t *regslen_p)
 
 
 Illegal cast, undefined behavior.
 
 -- 
 David A. Holland
 dholland%netbsd.org@localhost