arm64/boot: Disable trapping of PMZR_EL0 writes to EL2grafted

__init_el2_fgt2() writes one mask to both HDFGRTR2_EL2 and HDFGWTR2_EL2.
PMZR_EL0 is write-only, so its trap bit, nPMZR_EL0, exists only in
HDFGWTR2_EL2 and is therefore never set: a PMZR_EL0 write from the host
traps to EL2, where the nVHE hypervisor has no handler and BUG()s. The
kernel never writes PMZR_EL0, but kernel.perf_user_access=1 has the PMU
driver set PMUSERENR_EL0.UEN for a task with a user-read event, so a
write from EL0 reaches the trap and takes the host down without a panic
message.

Accumulate the HDFGWTR2_EL2 bits separately, as __init_el2_fgt() already
does for HDFGWTR_EL2, and set nPMZR_EL0 with the other FEAT_PMUv3p9
bits.

Fixes: 858c7bfcb35e1 ("arm64/boot: Enable EL2 requirements for FEAT_PMUv3p9")
Cc: stable@vger.kernel.org
Signed-off-by: Fuad Tabba <fuad.tabba@linux.dev>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Oliver Upton <oupton@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>

1 files changed, 208 insertions, 0 deletions

diff --git a/include/math-emu/quad.h b/include/math-emu/quad.h
new file mode 100644
index 000000000..616113626
--- /dev/null
+++ b/include/math-emu/quad.h
@@ -0,0 +1,208 @@
+/* Software floating-point emulation.
+   Definitions for IEEE Quad 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_QUAD_H__
+#define  __MATH_EMU_QUAD_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_Q         (4*_FP_W_TYPE_SIZE)
+#else
+#define _FP_FRACTBITS_Q		(2*_FP_W_TYPE_SIZE)
+#endif
+
+#define _FP_FRACBITS_Q		113
+#define _FP_FRACXBITS_Q		(_FP_FRACTBITS_Q - _FP_FRACBITS_Q)
+#define _FP_WFRACBITS_Q		(_FP_WORKBITS + _FP_FRACBITS_Q)
+#define _FP_WFRACXBITS_Q	(_FP_FRACTBITS_Q - _FP_WFRACBITS_Q)
+#define _FP_EXPBITS_Q		15
+#define _FP_EXPBIAS_Q		16383
+#define _FP_EXPMAX_Q		32767
+
+#define _FP_QNANBIT_Q		\
+	((_FP_W_TYPE)1 << (_FP_FRACBITS_Q-2) % _FP_W_TYPE_SIZE)
+#define _FP_IMPLBIT_Q		\
+	((_FP_W_TYPE)1 << (_FP_FRACBITS_Q-1) % _FP_W_TYPE_SIZE)
+#define _FP_OVERFLOW_Q		\
+	((_FP_W_TYPE)1 << (_FP_WFRACBITS_Q % _FP_W_TYPE_SIZE))
+
+#if _FP_W_TYPE_SIZE < 64
+
+union _FP_UNION_Q
+{
+   long double flt;
+   struct 
+   {
+#if __BYTE_ORDER == __BIG_ENDIAN
+      unsigned sign : 1;
+      unsigned exp : _FP_EXPBITS_Q;
+      unsigned long frac3 : _FP_FRACBITS_Q - (_FP_IMPLBIT_Q != 0)-(_FP_W_TYPE_SIZE * 3);
+      unsigned long frac2 : _FP_W_TYPE_SIZE;
+      unsigned long frac1 : _FP_W_TYPE_SIZE;
+      unsigned long frac0 : _FP_W_TYPE_SIZE;
+#else
+      unsigned long frac0 : _FP_W_TYPE_SIZE;
+      unsigned long frac1 : _FP_W_TYPE_SIZE;
+      unsigned long frac2 : _FP_W_TYPE_SIZE;
+      unsigned long frac3 : _FP_FRACBITS_Q - (_FP_IMPLBIT_Q != 0)-(_FP_W_TYPE_SIZE * 3);
+      unsigned exp : _FP_EXPBITS_Q;
+      unsigned sign : 1;
+#endif /* not bigendian */
+   } bits __attribute__((packed));
+};
+
+
+#define FP_DECL_Q(X)		_FP_DECL(4,X)
+#define FP_UNPACK_RAW_Q(X,val)	_FP_UNPACK_RAW_4(Q,X,val)
+#define FP_UNPACK_RAW_QP(X,val)	_FP_UNPACK_RAW_4_P(Q,X,val)
+#define FP_PACK_RAW_Q(val,X)	_FP_PACK_RAW_4(Q,val,X)
+#define FP_PACK_RAW_QP(val,X)		\
+  do {					\
+    if (!FP_INHIBIT_RESULTS)		\
+      _FP_PACK_RAW_4_P(Q,val,X);	\
+  } while (0)
+
+#define FP_UNPACK_Q(X,val)		\
+  do {					\
+    _FP_UNPACK_RAW_4(Q,X,val);		\
+    _FP_UNPACK_CANONICAL(Q,4,X);	\
+  } while (0)
+
+#define FP_UNPACK_QP(X,val)		\
+  do {					\
+    _FP_UNPACK_RAW_4_P(Q,X,val);	\
+    _FP_UNPACK_CANONICAL(Q,4,X);	\
+  } while (0)
+
+#define FP_PACK_Q(val,X)		\
+  do {					\
+    _FP_PACK_CANONICAL(Q,4,X);		\
+    _FP_PACK_RAW_4(Q,val,X);		\
+  } while (0)
+
+#define FP_PACK_QP(val,X)		\
+  do {					\
+    _FP_PACK_CANONICAL(Q,4,X);		\
+    if (!FP_INHIBIT_RESULTS)		\
+      _FP_PACK_RAW_4_P(Q,val,X);	\
+  } while (0)
+
+#define FP_ISSIGNAN_Q(X)		_FP_ISSIGNAN(Q,4,X)
+#define FP_NEG_Q(R,X)			_FP_NEG(Q,4,R,X)
+#define FP_ADD_Q(R,X,Y)			_FP_ADD(Q,4,R,X,Y)
+#define FP_SUB_Q(R,X,Y)			_FP_SUB(Q,4,R,X,Y)
+#define FP_MUL_Q(R,X,Y)			_FP_MUL(Q,4,R,X,Y)
+#define FP_DIV_Q(R,X,Y)			_FP_DIV(Q,4,R,X,Y)
+#define FP_SQRT_Q(R,X)			_FP_SQRT(Q,4,R,X)
+#define _FP_SQRT_MEAT_Q(R,S,T,X,Q)	_FP_SQRT_MEAT_4(R,S,T,X,Q)
+
+#define FP_CMP_Q(r,X,Y,un)	_FP_CMP(Q,4,r,X,Y,un)
+#define FP_CMP_EQ_Q(r,X,Y)	_FP_CMP_EQ(Q,4,r,X,Y)
+
+#define FP_TO_INT_Q(r,X,rsz,rsg)	_FP_TO_INT(Q,4,r,X,rsz,rsg)
+#define FP_TO_INT_ROUND_Q(r,X,rsz,rsg)	_FP_TO_INT_ROUND(Q,4,r,X,rsz,rsg)
+#define FP_FROM_INT_Q(X,r,rs,rt)	_FP_FROM_INT(Q,4,X,r,rs,rt)
+
+#define _FP_FRAC_HIGH_Q(X)	_FP_FRAC_HIGH_4(X)
+#define _FP_FRAC_HIGH_RAW_Q(X)	_FP_FRAC_HIGH_4(X)
+
+#else   /* not _FP_W_TYPE_SIZE < 64 */
+union _FP_UNION_Q
+{
+  long double flt /* __attribute__((mode(TF))) */ ;
+  struct {
+#if __BYTE_ORDER == __BIG_ENDIAN
+    unsigned sign  : 1;
+    unsigned exp   : _FP_EXPBITS_Q;
+    unsigned long frac1 : _FP_FRACBITS_Q-(_FP_IMPLBIT_Q != 0)-_FP_W_TYPE_SIZE;
+    unsigned long frac0 : _FP_W_TYPE_SIZE;
+#else
+    unsigned long frac0 : _FP_W_TYPE_SIZE;
+    unsigned long frac1 : _FP_FRACBITS_Q-(_FP_IMPLBIT_Q != 0)-_FP_W_TYPE_SIZE;
+    unsigned exp   : _FP_EXPBITS_Q;
+    unsigned sign  : 1;
+#endif
+  } bits;
+};
+
+#define FP_DECL_Q(X)		_FP_DECL(2,X)
+#define FP_UNPACK_RAW_Q(X,val)	_FP_UNPACK_RAW_2(Q,X,val)
+#define FP_UNPACK_RAW_QP(X,val)	_FP_UNPACK_RAW_2_P(Q,X,val)
+#define FP_PACK_RAW_Q(val,X)	_FP_PACK_RAW_2(Q,val,X)
+#define FP_PACK_RAW_QP(val,X)		\
+  do {					\
+    if (!FP_INHIBIT_RESULTS)		\
+      _FP_PACK_RAW_2_P(Q,val,X);	\
+  } while (0)
+
+#define FP_UNPACK_Q(X,val)		\
+  do {					\
+    _FP_UNPACK_RAW_2(Q,X,val);		\
+    _FP_UNPACK_CANONICAL(Q,2,X);	\
+  } while (0)
+
+#define FP_UNPACK_QP(X,val)		\
+  do {					\
+    _FP_UNPACK_RAW_2_P(Q,X,val);	\
+    _FP_UNPACK_CANONICAL(Q,2,X);	\
+  } while (0)
+
+#define FP_PACK_Q(val,X)		\
+  do {					\
+    _FP_PACK_CANONICAL(Q,2,X);		\
+    _FP_PACK_RAW_2(Q,val,X);		\
+  } while (0)
+
+#define FP_PACK_QP(val,X)		\
+  do {					\
+    _FP_PACK_CANONICAL(Q,2,X);		\
+    if (!FP_INHIBIT_RESULTS)		\
+      _FP_PACK_RAW_2_P(Q,val,X);	\
+  } while (0)
+
+#define FP_ISSIGNAN_Q(X)		_FP_ISSIGNAN(Q,2,X)
+#define FP_NEG_Q(R,X)			_FP_NEG(Q,2,R,X)
+#define FP_ADD_Q(R,X,Y)			_FP_ADD(Q,2,R,X,Y)
+#define FP_SUB_Q(R,X,Y)			_FP_SUB(Q,2,R,X,Y)
+#define FP_MUL_Q(R,X,Y)			_FP_MUL(Q,2,R,X,Y)
+#define FP_DIV_Q(R,X,Y)			_FP_DIV(Q,2,R,X,Y)
+#define FP_SQRT_Q(R,X)			_FP_SQRT(Q,2,R,X)
+#define _FP_SQRT_MEAT_Q(R,S,T,X,Q)	_FP_SQRT_MEAT_2(R,S,T,X,Q)
+
+#define FP_CMP_Q(r,X,Y,un)	_FP_CMP(Q,2,r,X,Y,un)
+#define FP_CMP_EQ_Q(r,X,Y)	_FP_CMP_EQ(Q,2,r,X,Y)
+
+#define FP_TO_INT_Q(r,X,rsz,rsg)	_FP_TO_INT(Q,2,r,X,rsz,rsg)
+#define FP_TO_INT_ROUND_Q(r,X,rsz,rsg)	_FP_TO_INT_ROUND(Q,2,r,X,rsz,rsg)
+#define FP_FROM_INT_Q(X,r,rs,rt)	_FP_FROM_INT(Q,2,X,r,rs,rt)
+
+#define _FP_FRAC_HIGH_Q(X)	_FP_FRAC_HIGH_2(X)
+#define _FP_FRAC_HIGH_RAW_Q(X)	_FP_FRAC_HIGH_2(X)
+
+#endif /* not _FP_W_TYPE_SIZE < 64 */
+
+#endif /* __MATH_EMU_QUAD_H__ */