mirror of
https://github.com/opnsense/src.git
synced 2026-06-19 21:49:14 -04:00
077e30e61d
Multiple issues existed within the powerpc FP/VSX save/restore functionality, leading to register corruption and loss of register contents in specific scenarios involving high signal load and use of both floating point and VSX instructions. Issue #1 On little endian systems the PCB used the wrong location for the shadowed FP register within the larger VSX register. This appears to have been an attempt to correct issue #2 without understanding how the vector load/store instructions actually operate. Issue #2 On little endian systems, the VSX state save/restore routines swapped 32-bit words within the 64-bit aliased double word for the associated floating point register. This was due to the use of a word-oriented load/store vs. doubleword oriented load/store. Issue #3 The FPU was turned off in the PCB but not in hardware, leading to a potential race condition if the same thread was scheduled immediately after sigreturn. The triggering codebase for this is Go, which makes heavy use of signals and and generates an unusual mix of floating point and VSX assembler. As a result, when combined with th powerpc lazy FPU restore, a condition was repeatedly hit whereby the thread was interrupted in FP+VSX mode, then restored in FP only mode, thus reliably triggering the issues above. Also clean up the associated asm() style issue flagged by GitHub Actions. Signed-off-by: Timothy Pearson <tpearson@raptorengineering.com> MFC after: 1 week Pull Request: https://github.com/freebsd/freebsd-src/pull/1756
93 lines
3.3 KiB
C
93 lines
3.3 KiB
C
/*-
|
|
* SPDX-License-Identifier: BSD-4-Clause
|
|
*
|
|
* Copyright (C) 1995, 1996 Wolfgang Solfrank.
|
|
* Copyright (C) 1995, 1996 TooLs GmbH.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by TooLs GmbH.
|
|
* 4. The name of TooLs GmbH may not be used to endorse or promote products
|
|
* derived from this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
|
* IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
|
|
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
|
|
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
|
|
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
|
|
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
|
|
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
* $NetBSD: signal.h,v 1.4 1998/09/14 02:48:34 thorpej Exp $
|
|
*/
|
|
|
|
#ifndef _MACHINE_UCONTEXT_H_
|
|
#define _MACHINE_UCONTEXT_H_
|
|
|
|
typedef struct __mcontext {
|
|
int mc_vers;
|
|
int mc_flags;
|
|
#define _MC_FP_VALID 0x01
|
|
#define _MC_AV_VALID 0x02
|
|
#define _MC_VS_VALID 0x04
|
|
int mc_onstack; /* saved onstack flag */
|
|
int mc_len; /* sizeof(__mcontext) */
|
|
__uint64_t mc_avec[32*2]; /* vector register file */
|
|
__uint32_t mc_av[2];
|
|
__register_t mc_frame[42];
|
|
__uint64_t mc_fpreg[33];
|
|
__uint64_t mc_vsxfpreg[32]; /* low-order half of VSR0-31 */
|
|
} mcontext_t __aligned(16);
|
|
|
|
#if defined(_KERNEL) && defined(__powerpc64__)
|
|
typedef struct __mcontext32 {
|
|
int mc_vers;
|
|
int mc_flags;
|
|
#define _MC_FP_VALID 0x01
|
|
#define _MC_AV_VALID 0x02
|
|
#define _MC_VS_VALID 0x04
|
|
int mc_onstack; /* saved onstack flag */
|
|
int mc_len; /* sizeof(__mcontext) */
|
|
uint64_t mc_avec[32*2]; /* vector register file */
|
|
uint32_t mc_av[2];
|
|
uint32_t mc_frame[42];
|
|
uint64_t mc_fpreg[33];
|
|
uint64_t mc_vsxfpreg[32]; /* low-order half of VSR0-31 */
|
|
} mcontext32_t __aligned(16);
|
|
#endif
|
|
|
|
/* GPRs and supervisor-level regs */
|
|
#define mc_gpr mc_frame
|
|
#define mc_lr mc_frame[32]
|
|
#define mc_cr mc_frame[33]
|
|
#define mc_xer mc_frame[34]
|
|
#define mc_ctr mc_frame[35]
|
|
#define mc_srr0 mc_frame[36]
|
|
#define mc_srr1 mc_frame[37]
|
|
#define mc_exc mc_frame[38]
|
|
#define mc_dar mc_frame[39]
|
|
#define mc_dsisr mc_frame[40]
|
|
|
|
/* floating-point state */
|
|
#define mc_fpscr mc_fpreg[32]
|
|
|
|
/* altivec state */
|
|
#define mc_vscr mc_av[0]
|
|
#define mc_vrsave mc_av[1]
|
|
|
|
#define _MC_VERSION 0x1
|
|
#define _MC_VERSION_KSE 0xee /* partial ucontext for libpthread */
|
|
|
|
#endif /* !_MACHINE_UCONTEXT_H_ */
|