linux/arch/arm64/kernel/cpu-reset.S
Sami Tolvanen c50d32859e arm64: Add types to indirect called assembly functions
With CONFIG_CFI_CLANG, assembly functions indirectly called from C
code must be annotated with type identifiers to pass CFI checking. Use
SYM_TYPED_FUNC_START for the indirectly called functions, and ensure
we emit `bti c` also with SYM_TYPED_FUNC_START.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220908215504.3686827-10-samitolvanen@google.com
2022-09-26 10:13:13 -07:00

54 lines
1.4 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* CPU reset routines
*
* Copyright (C) 2001 Deep Blue Solutions Ltd.
* Copyright (C) 2012 ARM Ltd.
* Copyright (C) 2015 Huawei Futurewei Technologies.
*/
#include <linux/linkage.h>
#include <linux/cfi_types.h>
#include <asm/assembler.h>
#include <asm/sysreg.h>
#include <asm/virt.h>
.text
.pushsection .idmap.text, "awx"
/*
* cpu_soft_restart(el2_switch, entry, arg0, arg1, arg2)
*
* @el2_switch: Flag to indicate a switch to EL2 is needed.
* @entry: Location to jump to for soft reset.
* arg0: First argument passed to @entry. (relocation list)
* arg1: Second argument passed to @entry.(physical kernel entry)
* arg2: Third argument passed to @entry. (physical dtb address)
*
* Put the CPU into the same state as it would be if it had been reset, and
* branch to what would be the reset vector. It must be executed with the
* flat identity mapping.
*/
SYM_TYPED_FUNC_START(cpu_soft_restart)
mov_q x12, INIT_SCTLR_EL1_MMU_OFF
pre_disable_mmu_workaround
/*
* either disable EL1&0 translation regime or disable EL2&0 translation
* regime if HCR_EL2.E2H == 1
*/
msr sctlr_el1, x12
isb
cbz x0, 1f // el2_switch?
mov x0, #HVC_SOFT_RESTART
hvc #0 // no return
1: mov x8, x1 // entry
mov x0, x2 // arg0
mov x1, x3 // arg1
mov x2, x4 // arg2
br x8
SYM_FUNC_END(cpu_soft_restart)
.popsection