freebsd-dev/sys/amd64/include/efi.h
Konstantin Belousov 185f7e0a9d amd64 ef_rt_arch_call: Preserve %rflags around call into EFI RT service.
If service code faulted, we might end up unwinding with interrupts
disabled.  Top-level kernel code should have interrupts enabled, which
is enforced by checks.

Save %rflags before entering EFI, and restore to the known good value
on return.  This handles situation with disabled interrupts on fault
and perhaps other potential bugs, e.g. invalid value for PSL_D.

Reported and tested by:	Jan Martin Mikkelsen <janm@transactionware.com>
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2019-06-03 15:32:42 +00:00

79 lines
2.6 KiB
C

/*-
* Copyright (c) 2016 The FreeBSD Foundation
* All rights reserved.
*
* This software was developed by Konstantin Belousov <kib@FreeBSD.org>
* under sponsorship from the FreeBSD Foundation.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 THE AUTHOR OR CONTRIBUTORS 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.
*
* $FreeBSD$
*/
#ifndef __AMD64_INCLUDE_EFI_H_
#define __AMD64_INCLUDE_EFI_H_
/*
* XXX: from gcc 6.2 manual:
* Note, the ms_abi attribute for Microsoft Windows 64-bit targets
* currently requires the -maccumulate-outgoing-args option.
*
* Avoid EFIABI_ATTR declarations for compilers that don't support it.
* GCC support began in version 4.4.
*/
#if defined(__clang__) || defined(__GNUC__) && \
(__GNUC__ > 4 || __GNUC__ == 4 && __GNUC_MINOR__ >= 4)
#define EFIABI_ATTR __attribute__((ms_abi))
#endif
#ifdef _KERNEL
#include <isa/rtc.h>
#define EFI_TIME_LOCK() mtx_lock(&atrtc_time_lock)
#define EFI_TIME_UNLOCK() mtx_unlock(&atrtc_time_lock)
#define EFI_TIME_OWNED() mtx_assert(&atrtc_time_lock, MA_OWNED)
#define EFI_RT_HANDLE_FAULTS_DEFAULT 1
#endif
struct efirt_callinfo {
const char *ec_name;
register_t ec_efi_status;
register_t ec_fptr;
register_t ec_argcnt;
register_t ec_arg1;
register_t ec_arg2;
register_t ec_arg3;
register_t ec_arg4;
register_t ec_arg5;
register_t ec_rbx;
register_t ec_rsp;
register_t ec_rbp;
register_t ec_r12;
register_t ec_r13;
register_t ec_r14;
register_t ec_r15;
register_t ec_rflags;
};
#endif /* __AMD64_INCLUDE_EFI_H_ */