Revision 070e76cb3ffe43f6855492e77c96680c562598f0 authored by Leonid Yegoshin on 27 November 2014, 11:13:08 UTC, committed by Ralf Baechle on 27 November 2014, 16:21:56 UTC
There is a potential race when probing the TLB in TLBL/M/S exception
handlers for a matching entry. Between the time we hit a TLBL/S/M
exception and the time we get to execute the TLBP instruction, the
HTW may have replaced the TLB entry we are interested in hence the TLB
probe may fail. However, in the existing handlers, we never checked the
status of the TLBP (ie check the result in the C0/Index register). We
fix this by adding such a check when the core implements the HTW. If
we couldn't find a matching entry, we return back and try again.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: <stable@vger.kernel.org> # v3.17+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8599/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
1 parent b4da18b
Raw File
double.h
/* Software floating-point emulation.
   Definitions for IEEE Double Precision
   Copyright (C) 1997,1998,1999 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Richard Henderson (rth@cygnus.com),
		  Jakub Jelinek (jj@ultra.linux.cz),
		  David S. Miller (davem@redhat.com) and
		  Peter Maydell (pmaydell@chiark.greenend.org.uk).

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If
   not, write to the Free Software Foundation, Inc.,
   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#ifndef    __MATH_EMU_DOUBLE_H__
#define    __MATH_EMU_DOUBLE_H__

#if _FP_W_TYPE_SIZE < 32
#error "Here's a nickel kid.  Go buy yourself a real computer."
#endif

#if _FP_W_TYPE_SIZE < 64
#define _FP_FRACTBITS_D		(2 * _FP_W_TYPE_SIZE)
#else
#define _FP_FRACTBITS_D		_FP_W_TYPE_SIZE
#endif

#define _FP_FRACBITS_D		53
#define _FP_FRACXBITS_D		(_FP_FRACTBITS_D - _FP_FRACBITS_D)
#define _FP_WFRACBITS_D		(_FP_WORKBITS + _FP_FRACBITS_D)
#define _FP_WFRACXBITS_D	(_FP_FRACTBITS_D - _FP_WFRACBITS_D)
#define _FP_EXPBITS_D		11
#define _FP_EXPBIAS_D		1023
#define _FP_EXPMAX_D		2047

#define _FP_QNANBIT_D		\
	((_FP_W_TYPE)1 << (_FP_FRACBITS_D-2) % _FP_W_TYPE_SIZE)
#define _FP_IMPLBIT_D		\
	((_FP_W_TYPE)1 << (_FP_FRACBITS_D-1) % _FP_W_TYPE_SIZE)
#define _FP_OVERFLOW_D		\
	((_FP_W_TYPE)1 << _FP_WFRACBITS_D % _FP_W_TYPE_SIZE)

#if _FP_W_TYPE_SIZE < 64

union _FP_UNION_D
{
  double flt;
  struct {
#if __BYTE_ORDER == __BIG_ENDIAN
    unsigned sign  : 1;
    unsigned exp   : _FP_EXPBITS_D;
    unsigned frac1 : _FP_FRACBITS_D - (_FP_IMPLBIT_D != 0) - _FP_W_TYPE_SIZE;
    unsigned frac0 : _FP_W_TYPE_SIZE;
#else
    unsigned frac0 : _FP_W_TYPE_SIZE;
    unsigned frac1 : _FP_FRACBITS_D - (_FP_IMPLBIT_D != 0) - _FP_W_TYPE_SIZE;
    unsigned exp   : _FP_EXPBITS_D;
    unsigned sign  : 1;
#endif
  } bits __attribute__((packed));
};

#define FP_DECL_D(X)		_FP_DECL(2,X)
#define FP_UNPACK_RAW_D(X,val)	_FP_UNPACK_RAW_2(D,X,val)
#define FP_UNPACK_RAW_DP(X,val)	_FP_UNPACK_RAW_2_P(D,X,val)
#define FP_PACK_RAW_D(val,X)	_FP_PACK_RAW_2(D,val,X)
#define FP_PACK_RAW_DP(val,X)		\
  do {					\
    if (!FP_INHIBIT_RESULTS)		\
      _FP_PACK_RAW_2_P(D,val,X);	\
  } while (0)

#define FP_UNPACK_D(X,val)		\
  do {					\
    _FP_UNPACK_RAW_2(D,X,val);		\
    _FP_UNPACK_CANONICAL(D,2,X);	\
  } while (0)

#define FP_UNPACK_DP(X,val)		\
  do {					\
    _FP_UNPACK_RAW_2_P(D,X,val);	\
    _FP_UNPACK_CANONICAL(D,2,X);	\
  } while (0)

#define FP_PACK_D(val,X)		\
  do {					\
    _FP_PACK_CANONICAL(D,2,X);		\
    _FP_PACK_RAW_2(D,val,X);		\
  } while (0)

#define FP_PACK_DP(val,X)		\
  do {					\
    _FP_PACK_CANONICAL(D,2,X);		\
    if (!FP_INHIBIT_RESULTS)		\
      _FP_PACK_RAW_2_P(D,val,X);	\
  } while (0)

#define FP_ISSIGNAN_D(X)		_FP_ISSIGNAN(D,2,X)
#define FP_NEG_D(R,X)			_FP_NEG(D,2,R,X)
#define FP_ADD_D(R,X,Y)			_FP_ADD(D,2,R,X,Y)
#define FP_SUB_D(R,X,Y)			_FP_SUB(D,2,R,X,Y)
#define FP_MUL_D(R,X,Y)			_FP_MUL(D,2,R,X,Y)
#define FP_DIV_D(R,X,Y)			_FP_DIV(D,2,R,X,Y)
#define FP_SQRT_D(R,X)			_FP_SQRT(D,2,R,X)
#define _FP_SQRT_MEAT_D(R,S,T,X,Q)	_FP_SQRT_MEAT_2(R,S,T,X,Q)

#define FP_CMP_D(r,X,Y,un)	_FP_CMP(D,2,r,X,Y,un)
#define FP_CMP_EQ_D(r,X,Y)	_FP_CMP_EQ(D,2,r,X,Y)

#define FP_TO_INT_D(r,X,rsz,rsg)	_FP_TO_INT(D,2,r,X,rsz,rsg)
#define FP_TO_INT_ROUND_D(r,X,rsz,rsg)	_FP_TO_INT_ROUND(D,2,r,X,rsz,rsg)
#define FP_FROM_INT_D(X,r,rs,rt)	_FP_FROM_INT(D,2,X,r,rs,rt)

#define _FP_FRAC_HIGH_D(X)	_FP_FRAC_HIGH_2(X)
#define _FP_FRAC_HIGH_RAW_D(X)	_FP_FRAC_HIGH_2(X)

#else

union _FP_UNION_D
{
  double flt;
  struct {
#if __BYTE_ORDER == __BIG_ENDIAN
    unsigned sign : 1;
    unsigned exp  : _FP_EXPBITS_D;
    unsigned long frac : _FP_FRACBITS_D - (_FP_IMPLBIT_D != 0);
#else
    unsigned long frac : _FP_FRACBITS_D - (_FP_IMPLBIT_D != 0);
    unsigned exp  : _FP_EXPBITS_D;
    unsigned sign : 1;
#endif
  } bits __attribute__((packed));
};

#define FP_DECL_D(X)		_FP_DECL(1,X)
#define FP_UNPACK_RAW_D(X,val)	_FP_UNPACK_RAW_1(D,X,val)
#define FP_UNPACK_RAW_DP(X,val)	_FP_UNPACK_RAW_1_P(D,X,val)
#define FP_PACK_RAW_D(val,X)	_FP_PACK_RAW_1(D,val,X)
#define FP_PACK_RAW_DP(val,X)		\
  do {					\
    if (!FP_INHIBIT_RESULTS)		\
      _FP_PACK_RAW_1_P(D,val,X);	\
  } while (0)

#define FP_UNPACK_D(X,val)		\
  do {					\
    _FP_UNPACK_RAW_1(D,X,val);		\
    _FP_UNPACK_CANONICAL(D,1,X);	\
  } while (0)

#define FP_UNPACK_DP(X,val)		\
  do {					\
    _FP_UNPACK_RAW_1_P(D,X,val);	\
    _FP_UNPACK_CANONICAL(D,1,X);	\
  } while (0)

#define FP_PACK_D(val,X)		\
  do {					\
    _FP_PACK_CANONICAL(D,1,X);		\
    _FP_PACK_RAW_1(D,val,X);		\
  } while (0)

#define FP_PACK_DP(val,X)		\
  do {					\
    _FP_PACK_CANONICAL(D,1,X);		\
    if (!FP_INHIBIT_RESULTS)		\
      _FP_PACK_RAW_1_P(D,val,X);	\
  } while (0)

#define FP_ISSIGNAN_D(X)		_FP_ISSIGNAN(D,1,X)
#define FP_NEG_D(R,X)			_FP_NEG(D,1,R,X)
#define FP_ADD_D(R,X,Y)			_FP_ADD(D,1,R,X,Y)
#define FP_SUB_D(R,X,Y)			_FP_SUB(D,1,R,X,Y)
#define FP_MUL_D(R,X,Y)			_FP_MUL(D,1,R,X,Y)
#define FP_DIV_D(R,X,Y)			_FP_DIV(D,1,R,X,Y)
#define FP_SQRT_D(R,X)			_FP_SQRT(D,1,R,X)
#define _FP_SQRT_MEAT_D(R,S,T,X,Q)	_FP_SQRT_MEAT_1(R,S,T,X,Q)

/* The implementation of _FP_MUL_D and _FP_DIV_D should be chosen by
   the target machine.  */

#define FP_CMP_D(r,X,Y,un)	_FP_CMP(D,1,r,X,Y,un)
#define FP_CMP_EQ_D(r,X,Y)	_FP_CMP_EQ(D,1,r,X,Y)

#define FP_TO_INT_D(r,X,rsz,rsg)	_FP_TO_INT(D,1,r,X,rsz,rsg)
#define FP_TO_INT_ROUND_D(r,X,rsz,rsg)	_FP_TO_INT_ROUND(D,1,r,X,rsz,rsg)
#define FP_FROM_INT_D(X,r,rs,rt)	_FP_FROM_INT(D,1,X,r,rs,rt)

#define _FP_FRAC_HIGH_D(X)	_FP_FRAC_HIGH_1(X)
#define _FP_FRAC_HIGH_RAW_D(X)	_FP_FRAC_HIGH_1(X)

#endif /* W_TYPE_SIZE < 64 */


#endif /* __MATH_EMU_DOUBLE_H__ */
back to top