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// SPDX-License-Identifier: GPL-2.0
/*
* Exception handling code
*
* Copyright (C) 2019 ARM Ltd.
*/
#include <linux/context_tracking.h>
#include <linux/ptrace.h>
#include <linux/thread_info.h>
#include <asm/cpufeature.h>
#include <asm/daifflags.h>
#include <asm/esr.h>
#include <asm/exception.h>
#include <asm/kprobes.h>
#include <asm/mmu.h>
#include <asm/sysreg.h>
static void notrace el1_abort(struct pt_regs *regs, unsigned long esr)
{
unsigned long far = read_sysreg(far_el1);
local_daif_inherit(regs);
far = untagged_addr(far);
do_mem_abort(far, esr, regs);
}
NOKPROBE_SYMBOL(el1_abort);
static void notrace el1_pc(struct pt_regs *regs, unsigned long esr)
{
unsigned long far = read_sysreg(far_el1);
local_daif_inherit(regs);
do_sp_pc_abort(far, esr, regs);
}
NOKPROBE_SYMBOL(el1_pc);
static void el1_undef(struct pt_regs *regs)
{
local_daif_inherit(regs);
do_undefinstr(regs);
}
NOKPROBE_SYMBOL(el1_undef);
static void el1_inv(struct pt_regs *regs, unsigned long esr)
{
local_daif_inherit(regs);
bad_mode(regs, 0, esr);
}
NOKPROBE_SYMBOL(el1_inv);
static void notrace el1_dbg(struct pt_regs *regs, unsigned long esr)
{
unsigned long far = read_sysreg(far_el1);
/*
* The CPU masked interrupts, and we are leaving them masked during
* do_debug_exception(). Update PMR as if we had called
* local_mask_daif().
*/
if (system_uses_irq_prio_masking())
gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);
do_debug_exception(far, esr, regs);
}
NOKPROBE_SYMBOL(el1_dbg);
asmlinkage void notrace el1_sync_handler(struct pt_regs *regs)
{
unsigned long esr = read_sysreg(esr_el1);
switch (ESR_ELx_EC(esr)) {
case ESR_ELx_EC_DABT_CUR:
case ESR_ELx_EC_IABT_CUR:
el1_abort(regs, esr);
break;
/*
* We don't handle ESR_ELx_EC_SP_ALIGN, since we will have hit a
* recursive exception when trying to push the initial pt_regs.
*/
case ESR_ELx_EC_PC_ALIGN:
el1_pc(regs, esr);
break;
case ESR_ELx_EC_SYS64:
case ESR_ELx_EC_UNKNOWN:
el1_undef(regs);
break;
case ESR_ELx_EC_BREAKPT_CUR:
case ESR_ELx_EC_SOFTSTP_CUR:
case ESR_ELx_EC_WATCHPT_CUR:
case ESR_ELx_EC_BRK64:
el1_dbg(regs, esr);
break;
default:
el1_inv(regs, esr);
};
}
NOKPROBE_SYMBOL(el1_sync_handler);
static void notrace el0_da(struct pt_regs *regs, unsigned long esr)
{
unsigned long far = read_sysreg(far_el1);
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
far = untagged_addr(far);
do_mem_abort(far, esr, regs);
}
NOKPROBE_SYMBOL(el0_da);
static void notrace el0_ia(struct pt_regs *regs, unsigned long esr)
{
unsigned long far = read_sysreg(far_el1);
/*
* We've taken an instruction abort from userspace and not yet
* re-enabled IRQs. If the address is a kernel address, apply
* BP hardening prior to enabling IRQs and pre-emption.
*/
if (!is_ttbr0_addr(far))
arm64_apply_bp_hardening();
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_mem_abort(far, esr, regs);
}
NOKPROBE_SYMBOL(el0_ia);
static void notrace el0_fpsimd_acc(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_fpsimd_acc(esr, regs);
}
NOKPROBE_SYMBOL(el0_fpsimd_acc);
static void notrace el0_sve_acc(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_sve_acc(esr, regs);
}
NOKPROBE_SYMBOL(el0_sve_acc);
static void notrace el0_fpsimd_exc(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_fpsimd_exc(esr, regs);
}
NOKPROBE_SYMBOL(el0_fpsimd_exc);
static void notrace el0_sys(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_sysinstr(esr, regs);
}
NOKPROBE_SYMBOL(el0_sys);
static void notrace el0_pc(struct pt_regs *regs, unsigned long esr)
{
unsigned long far = read_sysreg(far_el1);
if (!is_ttbr0_addr(instruction_pointer(regs)))
arm64_apply_bp_hardening();
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_sp_pc_abort(far, esr, regs);
}
NOKPROBE_SYMBOL(el0_pc);
static void notrace el0_sp(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX_NOIRQ);
do_sp_pc_abort(regs->sp, esr, regs);
}
NOKPROBE_SYMBOL(el0_sp);
static void notrace el0_undef(struct pt_regs *regs)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_undefinstr(regs);
}
NOKPROBE_SYMBOL(el0_undef);
static void notrace el0_inv(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
bad_el0_sync(regs, 0, esr);
}
NOKPROBE_SYMBOL(el0_inv);
static void notrace el0_dbg(struct pt_regs *regs, unsigned long esr)
{
/* Only watchpoints write FAR_EL1, otherwise its UNKNOWN */
unsigned long far = read_sysreg(far_el1);
if (system_uses_irq_prio_masking())
gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);
user_exit_irqoff();
do_debug_exception(far, esr, regs);
local_daif_restore(DAIF_PROCCTX_NOIRQ);
}
NOKPROBE_SYMBOL(el0_dbg);
static void notrace el0_svc(struct pt_regs *regs)
{
if (system_uses_irq_prio_masking())
gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);
el0_svc_handler(regs);
}
NOKPROBE_SYMBOL(el0_svc);
asmlinkage void notrace el0_sync_handler(struct pt_regs *regs)
{
unsigned long esr = read_sysreg(esr_el1);
switch (ESR_ELx_EC(esr)) {
case ESR_ELx_EC_SVC64:
el0_svc(regs);
break;
case ESR_ELx_EC_DABT_LOW:
el0_da(regs, esr);
break;
case ESR_ELx_EC_IABT_LOW:
el0_ia(regs, esr);
break;
case ESR_ELx_EC_FP_ASIMD:
el0_fpsimd_acc(regs, esr);
break;
case ESR_ELx_EC_SVE:
el0_sve_acc(regs, esr);
break;
case ESR_ELx_EC_FP_EXC64:
el0_fpsimd_exc(regs, esr);
break;
case ESR_ELx_EC_SYS64:
case ESR_ELx_EC_WFx:
el0_sys(regs, esr);
break;
case ESR_ELx_EC_SP_ALIGN:
el0_sp(regs, esr);
break;
case ESR_ELx_EC_PC_ALIGN:
el0_pc(regs, esr);
break;
case ESR_ELx_EC_UNKNOWN:
el0_undef(regs);
break;
case ESR_ELx_EC_BREAKPT_LOW:
case ESR_ELx_EC_SOFTSTP_LOW:
case ESR_ELx_EC_WATCHPT_LOW:
case ESR_ELx_EC_BRK64:
el0_dbg(regs, esr);
break;
default:
el0_inv(regs, esr);
}
}
NOKPROBE_SYMBOL(el0_sync_handler);
#ifdef CONFIG_COMPAT
static void notrace el0_cp15(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_cp15instr(esr, regs);
}
NOKPROBE_SYMBOL(el0_cp15);
static void notrace el0_svc_compat(struct pt_regs *regs)
{
if (system_uses_irq_prio_masking())
gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);
el0_svc_compat_handler(regs);
}
NOKPROBE_SYMBOL(el0_svc_compat);
asmlinkage void notrace el0_sync_compat_handler(struct pt_regs *regs)
{
unsigned long esr = read_sysreg(esr_el1);
switch (ESR_ELx_EC(esr)) {
case ESR_ELx_EC_SVC32:
el0_svc_compat(regs);
break;
case ESR_ELx_EC_DABT_LOW:
el0_da(regs, esr);
break;
case ESR_ELx_EC_IABT_LOW:
el0_ia(regs, esr);
break;
case ESR_ELx_EC_FP_ASIMD:
el0_fpsimd_acc(regs, esr);
break;
case ESR_ELx_EC_FP_EXC32:
el0_fpsimd_exc(regs, esr);
break;
case ESR_ELx_EC_PC_ALIGN:
el0_pc(regs, esr);
break;
case ESR_ELx_EC_UNKNOWN:
case ESR_ELx_EC_CP14_MR:
case ESR_ELx_EC_CP14_LS:
case ESR_ELx_EC_CP14_64:
el0_undef(regs);
break;
case ESR_ELx_EC_CP15_32:
case ESR_ELx_EC_CP15_64:
el0_cp15(regs, esr);
break;
case ESR_ELx_EC_BREAKPT_LOW:
case ESR_ELx_EC_SOFTSTP_LOW:
case ESR_ELx_EC_WATCHPT_LOW:
case ESR_ELx_EC_BKPT32:
el0_dbg(regs, esr);
break;
default:
el0_inv(regs, esr);
}
}
NOKPROBE_SYMBOL(el0_sync_compat_handler);
#endif /* CONFIG_COMPAT */
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