diff options
Diffstat (limited to 'arch/arm64/mm/fault.c')
| -rw-r--r-- | arch/arm64/mm/fault.c | 67 |
1 files changed, 42 insertions, 25 deletions
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 1a7e92ab69eb..2d115016feb4 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -1,21 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Based on arch/arm/mm/fault.c * * Copyright (C) 1995 Linus Torvalds * Copyright (C) 1995-2004 Russell King * Copyright (C) 2012 ARM Ltd. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * This program 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 General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <linux/acpi.h> @@ -148,7 +137,7 @@ static inline bool is_ttbr1_addr(unsigned long addr) /* * Dump out the page tables associated with 'addr' in the currently active mm. */ -void show_pte(unsigned long addr) +static void show_pte(unsigned long addr) { struct mm_struct *mm; pgd_t *pgdp; @@ -171,9 +160,10 @@ void show_pte(unsigned long addr) return; } - pr_alert("%s pgtable: %luk pages, %u-bit VAs, pgdp = %p\n", + pr_alert("%s pgtable: %luk pages, %u-bit VAs, pgdp=%016lx\n", mm == &init_mm ? "swapper" : "user", PAGE_SIZE / SZ_1K, - mm == &init_mm ? VA_BITS : (int) vabits_user, mm->pgd); + mm == &init_mm ? VA_BITS : (int)vabits_user, + (unsigned long)virt_to_phys(mm->pgd)); pgdp = pgd_offset(mm, addr); pgd = READ_ONCE(*pgdp); pr_alert("[%016lx] pgd=%016llx", addr, pgd_val(pgd)); @@ -810,13 +800,45 @@ void __init hook_debug_fault_code(int nr, debug_fault_info[nr].name = name; } -asmlinkage int __exception do_debug_exception(unsigned long addr_if_watchpoint, - unsigned int esr, - struct pt_regs *regs) +#ifdef CONFIG_ARM64_ERRATUM_1463225 +DECLARE_PER_CPU(int, __in_cortex_a76_erratum_1463225_wa); + +static int __exception +cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs) +{ + if (user_mode(regs)) + return 0; + + if (!__this_cpu_read(__in_cortex_a76_erratum_1463225_wa)) + return 0; + + /* + * We've taken a dummy step exception from the kernel to ensure + * that interrupts are re-enabled on the syscall path. Return back + * to cortex_a76_erratum_1463225_svc_handler() with debug exceptions + * masked so that we can safely restore the mdscr and get on with + * handling the syscall. + */ + regs->pstate |= PSR_D_BIT; + return 1; +} +#else +static int __exception +cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs) +{ + return 0; +} +#endif /* CONFIG_ARM64_ERRATUM_1463225 */ + +asmlinkage void __exception do_debug_exception(unsigned long addr_if_watchpoint, + unsigned int esr, + struct pt_regs *regs) { const struct fault_info *inf = esr_to_debug_fault_info(esr); unsigned long pc = instruction_pointer(regs); - int rv; + + if (cortex_a76_erratum_1463225_debug_handler(regs)) + return; /* * Tell lockdep we disabled irqs in entry.S. Do nothing if they were @@ -828,17 +850,12 @@ asmlinkage int __exception do_debug_exception(unsigned long addr_if_watchpoint, if (user_mode(regs) && !is_ttbr0_addr(pc)) arm64_apply_bp_hardening(); - if (!inf->fn(addr_if_watchpoint, esr, regs)) { - rv = 1; - } else { + if (inf->fn(addr_if_watchpoint, esr, regs)) { arm64_notify_die(inf->name, regs, inf->sig, inf->code, (void __user *)pc, esr); - rv = 0; } if (interrupts_enabled(regs)) trace_hardirqs_on(); - - return rv; } NOKPROBE_SYMBOL(do_debug_exception); |