diff options
| -rw-r--r-- | arch/powerpc/Kconfig | 1 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/interrupt.h | 384 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/kasan.h | 15 | ||||
| -rw-r--r-- | arch/powerpc/kernel/interrupt.c | 250 | ||||
| -rw-r--r-- | arch/powerpc/kernel/ptrace/ptrace.c | 3 | ||||
| -rw-r--r-- | arch/powerpc/kernel/signal.c | 8 | ||||
| -rw-r--r-- | arch/powerpc/kernel/syscall.c | 119 |
7 files changed, 124 insertions, 656 deletions
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index e93df95b79e7..81642206f7de 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -206,6 +206,7 @@ config PPC select GENERIC_CPU_AUTOPROBE select GENERIC_CPU_VULNERABILITIES if PPC_BARRIER_NOSPEC select GENERIC_EARLY_IOREMAP + select GENERIC_ENTRY select GENERIC_GETTIMEOFDAY select GENERIC_IDLE_POLL_SETUP select GENERIC_IOREMAP diff --git a/arch/powerpc/include/asm/interrupt.h b/arch/powerpc/include/asm/interrupt.h index 0e2cddf8bd21..fb42a664ae54 100644 --- a/arch/powerpc/include/asm/interrupt.h +++ b/arch/powerpc/include/asm/interrupt.h @@ -66,11 +66,9 @@ #ifndef __ASSEMBLER__ -#include <linux/context_tracking.h> -#include <linux/hardirq.h> -#include <asm/cputime.h> -#include <asm/firmware.h> -#include <asm/ftrace.h> +#include <linux/sched/debug.h> /* for show_regs */ +#include <linux/irq-entry-common.h> + #include <asm/kprobes.h> #include <asm/runlatch.h> @@ -88,308 +86,6 @@ do { \ #define INT_SOFT_MASK_BUG_ON(regs, cond) #endif -#ifdef CONFIG_PPC_BOOK3S_64 -extern char __end_soft_masked[]; -bool search_kernel_soft_mask_table(unsigned long addr); -unsigned long search_kernel_restart_table(unsigned long addr); - -DECLARE_STATIC_KEY_FALSE(interrupt_exit_not_reentrant); - -static inline bool is_implicit_soft_masked(struct pt_regs *regs) -{ - if (user_mode(regs)) - return false; - - if (regs->nip >= (unsigned long)__end_soft_masked) - return false; - - return search_kernel_soft_mask_table(regs->nip); -} - -static inline void srr_regs_clobbered(void) -{ - local_paca->srr_valid = 0; - local_paca->hsrr_valid = 0; -} -#else -static inline unsigned long search_kernel_restart_table(unsigned long addr) -{ - return 0; -} - -static inline bool is_implicit_soft_masked(struct pt_regs *regs) -{ - return false; -} - -static inline void srr_regs_clobbered(void) -{ -} -#endif - -static inline void nap_adjust_return(struct pt_regs *regs) -{ -#ifdef CONFIG_PPC_970_NAP - if (unlikely(test_thread_local_flags(_TLF_NAPPING))) { - /* Can avoid a test-and-clear because NMIs do not call this */ - clear_thread_local_flags(_TLF_NAPPING); - regs_set_return_ip(regs, (unsigned long)power4_idle_nap_return); - } -#endif -} - -static inline void booke_restore_dbcr0(void) -{ -#ifdef CONFIG_PPC_ADV_DEBUG_REGS - unsigned long dbcr0 = current->thread.debug.dbcr0; - - if (IS_ENABLED(CONFIG_PPC32) && unlikely(dbcr0 & DBCR0_IDM)) { - mtspr(SPRN_DBSR, -1); - mtspr(SPRN_DBCR0, global_dbcr0[smp_processor_id()]); - } -#endif -} - -static inline void interrupt_enter_prepare(struct pt_regs *regs) -{ -#ifdef CONFIG_PPC64 - irq_soft_mask_set(IRQS_ALL_DISABLED); - - /* - * If the interrupt was taken with HARD_DIS clear, then enable MSR[EE]. - * Asynchronous interrupts get here with HARD_DIS set (see below), so - * this enables MSR[EE] for synchronous interrupts. IRQs remain - * soft-masked. The interrupt handler may later call - * interrupt_cond_local_irq_enable() to achieve a regular process - * context. - */ - if (!(local_paca->irq_happened & PACA_IRQ_HARD_DIS)) { - INT_SOFT_MASK_BUG_ON(regs, !(regs->msr & MSR_EE)); - __hard_irq_enable(); - } else { - __hard_RI_enable(); - } - /* Enable MSR[RI] early, to support kernel SLB and hash faults */ -#endif - - if (!regs_irqs_disabled(regs)) - trace_hardirqs_off(); - - if (user_mode(regs)) { - kuap_lock(); - CT_WARN_ON(ct_state() != CT_STATE_USER); - user_exit_irqoff(); - - account_cpu_user_entry(); - account_stolen_time(); - } else { - kuap_save_and_lock(regs); - /* - * CT_WARN_ON comes here via program_check_exception, - * so avoid recursion. - */ - if (TRAP(regs) != INTERRUPT_PROGRAM) - CT_WARN_ON(ct_state() != CT_STATE_KERNEL && - ct_state() != CT_STATE_IDLE); - INT_SOFT_MASK_BUG_ON(regs, is_implicit_soft_masked(regs)); - INT_SOFT_MASK_BUG_ON(regs, regs_irqs_disabled(regs) && - search_kernel_restart_table(regs->nip)); - } - INT_SOFT_MASK_BUG_ON(regs, !regs_irqs_disabled(regs) && - !(regs->msr & MSR_EE)); - - booke_restore_dbcr0(); -} - -/* - * Care should be taken to note that interrupt_exit_prepare and - * interrupt_async_exit_prepare do not necessarily return immediately to - * regs context (e.g., if regs is usermode, we don't necessarily return to - * user mode). Other interrupts might be taken between here and return, - * context switch / preemption may occur in the exit path after this, or a - * signal may be delivered, etc. - * - * The real interrupt exit code is platform specific, e.g., - * interrupt_exit_user_prepare / interrupt_exit_kernel_prepare for 64s. - * - * However interrupt_nmi_exit_prepare does return directly to regs, because - * NMIs do not do "exit work" or replay soft-masked interrupts. - */ -static inline void interrupt_exit_prepare(struct pt_regs *regs) -{ -} - -static inline void interrupt_async_enter_prepare(struct pt_regs *regs) -{ -#ifdef CONFIG_PPC64 - /* Ensure interrupt_enter_prepare does not enable MSR[EE] */ - local_paca->irq_happened |= PACA_IRQ_HARD_DIS; -#endif - interrupt_enter_prepare(regs); -#ifdef CONFIG_PPC_BOOK3S_64 - /* - * RI=1 is set by interrupt_enter_prepare, so this thread flags access - * has to come afterward (it can cause SLB faults). - */ - if (cpu_has_feature(CPU_FTR_CTRL) && - !test_thread_local_flags(_TLF_RUNLATCH)) - __ppc64_runlatch_on(); -#endif - irq_enter(); -} - -static inline void interrupt_async_exit_prepare(struct pt_regs *regs) -{ - /* - * Adjust at exit so the main handler sees the true NIA. This must - * come before irq_exit() because irq_exit can enable interrupts, and - * if another interrupt is taken before nap_adjust_return has run - * here, then that interrupt would return directly to idle nap return. - */ - nap_adjust_return(regs); - - irq_exit(); - interrupt_exit_prepare(regs); -} - -struct interrupt_nmi_state { -#ifdef CONFIG_PPC64 - u8 irq_soft_mask; - u8 irq_happened; - u8 ftrace_enabled; - u64 softe; -#endif -}; - -static inline bool nmi_disables_ftrace(struct pt_regs *regs) -{ - /* Allow DEC and PMI to be traced when they are soft-NMI */ - if (IS_ENABLED(CONFIG_PPC_BOOK3S_64)) { - if (TRAP(regs) == INTERRUPT_DECREMENTER) - return false; - if (TRAP(regs) == INTERRUPT_PERFMON) - return false; - } - if (IS_ENABLED(CONFIG_PPC_BOOK3E_64)) { - if (TRAP(regs) == INTERRUPT_PERFMON) - return false; - } - - return true; -} - -static inline void interrupt_nmi_enter_prepare(struct pt_regs *regs, struct interrupt_nmi_state *state) -{ -#ifdef CONFIG_PPC64 - state->irq_soft_mask = local_paca->irq_soft_mask; - state->irq_happened = local_paca->irq_happened; - state->softe = regs->softe; - - /* - * Set IRQS_ALL_DISABLED unconditionally so irqs_disabled() does - * the right thing, and set IRQ_HARD_DIS. We do not want to reconcile - * because that goes through irq tracing which we don't want in NMI. - */ - local_paca->irq_soft_mask = IRQS_ALL_DISABLED; - local_paca->irq_happened |= PACA_IRQ_HARD_DIS; - - if (!(regs->msr & MSR_EE) || is_implicit_soft_masked(regs)) { - /* - * Adjust regs->softe to be soft-masked if it had not been - * reconcied (e.g., interrupt entry with MSR[EE]=0 but softe - * not yet set disabled), or if it was in an implicit soft - * masked state. This makes regs_irqs_disabled(regs) - * behave as expected. - */ - regs->softe = IRQS_ALL_DISABLED; - } - - __hard_RI_enable(); - - /* Don't do any per-CPU operations until interrupt state is fixed */ - - if (nmi_disables_ftrace(regs)) { - state->ftrace_enabled = this_cpu_get_ftrace_enabled(); - this_cpu_set_ftrace_enabled(0); - } -#endif - - /* If data relocations are enabled, it's safe to use nmi_enter() */ - if (mfmsr() & MSR_DR) { - nmi_enter(); - return; - } - - /* - * But do not use nmi_enter() for pseries hash guest taking a real-mode - * NMI because not everything it touches is within the RMA limit. - */ - if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && - firmware_has_feature(FW_FEATURE_LPAR) && - !radix_enabled()) - return; - - /* - * Likewise, don't use it if we have some form of instrumentation (like - * KASAN shadow) that is not safe to access in real mode (even on radix) - */ - if (IS_ENABLED(CONFIG_KASAN)) - return; - - /* - * Likewise, do not use it in real mode if percpu first chunk is not - * embedded. With CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK enabled there - * are chances where percpu allocation can come from vmalloc area. - */ - if (percpu_first_chunk_is_paged) - return; - - /* Otherwise, it should be safe to call it */ - nmi_enter(); -} - -static inline void interrupt_nmi_exit_prepare(struct pt_regs *regs, struct interrupt_nmi_state *state) -{ - if (mfmsr() & MSR_DR) { - // nmi_exit if relocations are on - nmi_exit(); - } else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && - firmware_has_feature(FW_FEATURE_LPAR) && - !radix_enabled()) { - // no nmi_exit for a pseries hash guest taking a real mode exception - } else if (IS_ENABLED(CONFIG_KASAN)) { - // no nmi_exit for KASAN in real mode - } else if (percpu_first_chunk_is_paged) { - // no nmi_exit if percpu first chunk is not embedded - } else { - nmi_exit(); - } - - /* - * nmi does not call nap_adjust_return because nmi should not create - * new work to do (must use irq_work for that). - */ - -#ifdef CONFIG_PPC64 -#ifdef CONFIG_PPC_BOOK3S - if (regs_irqs_disabled(regs)) { - unsigned long rst = search_kernel_restart_table(regs->nip); - if (rst) - regs_set_return_ip(regs, rst); - } -#endif - - if (nmi_disables_ftrace(regs)) - this_cpu_set_ftrace_enabled(state->ftrace_enabled); - - /* Check we didn't change the pending interrupt mask. */ - WARN_ON_ONCE((state->irq_happened | PACA_IRQ_HARD_DIS) != local_paca->irq_happened); - regs->softe = state->softe; - local_paca->irq_happened = state->irq_happened; - local_paca->irq_soft_mask = state->irq_soft_mask; -#endif -} - /* * Don't use noinstr here like x86, but rather add NOKPROBE_SYMBOL to each * function definition. The reason for this is the noinstr section is placed @@ -470,11 +166,14 @@ static __always_inline void ____##func(struct pt_regs *regs); \ \ interrupt_handler void func(struct pt_regs *regs) \ { \ - interrupt_enter_prepare(regs); \ - \ + irqentry_state_t state; \ + arch_interrupt_enter_prepare(regs); \ + state = irqentry_enter(regs); \ + instrumentation_begin(); \ ____##func (regs); \ - \ - interrupt_exit_prepare(regs); \ + instrumentation_end(); \ + arch_interrupt_exit_prepare(regs); \ + irqentry_exit(regs, state); \ } \ NOKPROBE_SYMBOL(func); \ \ @@ -504,12 +203,15 @@ static __always_inline long ____##func(struct pt_regs *regs); \ interrupt_handler long func(struct pt_regs *regs) \ { \ long ret; \ + irqentry_state_t state; \ \ - interrupt_enter_prepare(regs); \ - \ + arch_interrupt_enter_prepare(regs); \ + state = irqentry_enter(regs); \ + instrumentation_begin(); \ ret = ____##func (regs); \ - \ - interrupt_exit_prepare(regs); \ + instrumentation_end(); \ + arch_interrupt_exit_prepare(regs); \ + irqentry_exit(regs, state); \ \ return ret; \ } \ @@ -538,11 +240,16 @@ static __always_inline void ____##func(struct pt_regs *regs); \ \ interrupt_handler void func(struct pt_regs *regs) \ { \ - interrupt_async_enter_prepare(regs); \ - \ + irqentry_state_t state; \ + arch_interrupt_async_enter_prepare(regs); \ + state = irqentry_enter(regs); \ + instrumentation_begin(); \ + irq_enter_rcu(); \ ____##func (regs); \ - \ - interrupt_async_exit_prepare(regs); \ + irq_exit_rcu(); \ + instrumentation_end(); \ + arch_interrupt_async_exit_prepare(regs); \ + irqentry_exit(regs, state); \ } \ NOKPROBE_SYMBOL(func); \ \ @@ -572,14 +279,43 @@ ____##func(struct pt_regs *regs); \ \ interrupt_handler long func(struct pt_regs *regs) \ { \ - struct interrupt_nmi_state state; \ + irqentry_state_t state; \ + struct interrupt_nmi_state nmi_state; \ long ret; \ \ - interrupt_nmi_enter_prepare(regs, &state); \ - \ + arch_interrupt_nmi_enter_prepare(regs, &nmi_state); \ + if (mfmsr() & MSR_DR) { \ + /* nmi_entry if relocations are on */ \ + state = irqentry_nmi_enter(regs); \ + } else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && \ + firmware_has_feature(FW_FEATURE_LPAR) && \ + !radix_enabled()) { \ + /* no nmi_entry for a pseries hash guest \ + * taking a real mode exception */ \ + } else if (IS_ENABLED(CONFIG_KASAN)) { \ + /* no nmi_entry for KASAN in real mode */ \ + } else if (percpu_first_chunk_is_paged) { \ + /* no nmi_entry if percpu first chunk is not embedded */\ + } else { \ + state = irqentry_nmi_enter(regs); \ + } \ ret = ____##func (regs); \ - \ - interrupt_nmi_exit_prepare(regs, &state); \ + arch_interrupt_nmi_exit_prepare(regs, &nmi_state); \ + if (mfmsr() & MSR_DR) { \ + /* nmi_exit if relocations are on */ \ + irqentry_nmi_exit(regs, state); \ + } else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && \ + firmware_has_feature(FW_FEATURE_LPAR) && \ + !radix_enabled()) { \ + /* no nmi_exit for a pseries hash guest \ + * taking a real mode exception */ \ + } else if (IS_ENABLED(CONFIG_KASAN)) { \ + /* no nmi_exit for KASAN in real mode */ \ + } else if (percpu_first_chunk_is_paged) { \ + /* no nmi_exit if percpu first chunk is not embedded */ \ + } else { \ + irqentry_nmi_exit(regs, state); \ + } \ \ return ret; \ } \ diff --git a/arch/powerpc/include/asm/kasan.h b/arch/powerpc/include/asm/kasan.h index 045804a86f98..a690e7da53c2 100644 --- a/arch/powerpc/include/asm/kasan.h +++ b/arch/powerpc/include/asm/kasan.h @@ -3,14 +3,19 @@ #define __ASM_KASAN_H #if defined(CONFIG_KASAN) && !defined(CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX) -#define _GLOBAL_KASAN(fn) _GLOBAL(__##fn) -#define _GLOBAL_TOC_KASAN(fn) _GLOBAL_TOC(__##fn) -#define EXPORT_SYMBOL_KASAN(fn) EXPORT_SYMBOL(__##fn) -#else +#define _GLOBAL_KASAN(fn) \ + _GLOBAL(fn); \ + _GLOBAL(__##fn) +#define _GLOBAL_TOC_KASAN(fn) \ + _GLOBAL_TOC(fn); \ + _GLOBAL_TOC(__##fn) +#define EXPORT_SYMBOL_KASAN(fn) \ + EXPORT_SYMBOL(__##fn) +#else /* CONFIG_KASAN && !CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX */ #define _GLOBAL_KASAN(fn) _GLOBAL(fn) #define _GLOBAL_TOC_KASAN(fn) _GLOBAL_TOC(fn) #define EXPORT_SYMBOL_KASAN(fn) -#endif +#endif /* CONFIG_KASAN && !CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX */ #ifndef __ASSEMBLER__ diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c index 666eadb589a5..89a999be1352 100644 --- a/arch/powerpc/kernel/interrupt.c +++ b/arch/powerpc/kernel/interrupt.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0-or-later #include <linux/context_tracking.h> +#include <linux/entry-common.h> #include <linux/err.h> #include <linux/compat.h> #include <linux/rseq.h> @@ -25,10 +26,6 @@ unsigned long global_dbcr0[NR_CPUS]; #endif -#if defined(CONFIG_PREEMPT_DYNAMIC) -DEFINE_STATIC_KEY_TRUE(sk_dynamic_irqentry_exit_cond_resched); -#endif - #ifdef CONFIG_PPC_BOOK3S_64 DEFINE_STATIC_KEY_FALSE(interrupt_exit_not_reentrant); static inline bool exit_must_hard_disable(void) @@ -78,181 +75,6 @@ static notrace __always_inline bool prep_irq_for_enabled_exit(bool restartable) return true; } -static notrace void booke_load_dbcr0(void) -{ -#ifdef CONFIG_PPC_ADV_DEBUG_REGS - unsigned long dbcr0 = current->thread.debug.dbcr0; - - if (likely(!(dbcr0 & DBCR0_IDM))) - return; - - /* - * Check to see if the dbcr0 register is set up to debug. - * Use the internal debug mode bit to do this. - */ - mtmsr(mfmsr() & ~MSR_DE); - if (IS_ENABLED(CONFIG_PPC32)) { - isync(); - global_dbcr0[smp_processor_id()] = mfspr(SPRN_DBCR0); - } - mtspr(SPRN_DBCR0, dbcr0); - mtspr(SPRN_DBSR, -1); -#endif -} - -static notrace void check_return_regs_valid(struct pt_regs *regs) -{ -#ifdef CONFIG_PPC_BOOK3S_64 - unsigned long trap, srr0, srr1; - static bool warned; - u8 *validp; - char *h; - - if (trap_is_scv(regs)) - return; - - trap = TRAP(regs); - // EE in HV mode sets HSRRs like 0xea0 - if (cpu_has_feature(CPU_FTR_HVMODE) && trap == INTERRUPT_EXTERNAL) - trap = 0xea0; - - switch (trap) { - case 0x980: - case INTERRUPT_H_DATA_STORAGE: - case 0xe20: - case 0xe40: - case INTERRUPT_HMI: - case 0xe80: - case 0xea0: - case INTERRUPT_H_FAC_UNAVAIL: - case 0x1200: - case 0x1500: - case 0x1600: - case 0x1800: - validp = &local_paca->hsrr_valid; - if (!READ_ONCE(*validp)) - return; - - srr0 = mfspr(SPRN_HSRR0); - srr1 = mfspr(SPRN_HSRR1); - h = "H"; - - break; - default: - validp = &local_paca->srr_valid; - if (!READ_ONCE(*validp)) - return; - - srr0 = mfspr(SPRN_SRR0); - srr1 = mfspr(SPRN_SRR1); - h = ""; - break; - } - - if (srr0 == regs->nip && srr1 == regs->msr) - return; - - /* - * A NMI / soft-NMI interrupt may have come in after we found - * srr_valid and before the SRRs are loaded. The interrupt then - * comes in and clobbers SRRs and clears srr_valid. Then we load - * the SRRs here and test them above and find they don't match. - * - * Test validity again after that, to catch such false positives. - * - * This test in general will have some window for false negatives - * and may not catch and fix all such cases if an NMI comes in - * later and clobbers SRRs without clearing srr_valid, but hopefully - * such things will get caught most of the time, statistically - * enough to be able to get a warning out. - */ - if (!READ_ONCE(*validp)) - return; - - if (!data_race(warned)) { - data_race(warned = true); - printk("%sSRR0 was: %lx should be: %lx\n", h, srr0, regs->nip); - printk("%sSRR1 was: %lx should be: %lx\n", h, srr1, regs->msr); - show_regs(regs); - } - - WRITE_ONCE(*validp, 0); /* fixup */ -#endif -} - -static notrace unsigned long -interrupt_exit_user_prepare_main(unsigned long ret, struct pt_regs *regs) -{ - unsigned long ti_flags; - -again: - ti_flags = read_thread_flags(); - while (unlikely(ti_flags & (_TIF_USER_WORK_MASK & ~_TIF_RESTORE_TM))) { - local_irq_enable(); - if (ti_flags & (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)) { - schedule(); - } else { - /* - * SIGPENDING must restore signal handler function - * argument GPRs, and some non-volatiles (e.g., r1). - * Restore all for now. This could be made lighter. - */ - if (ti_flags & _TIF_SIGPENDING) - ret |= _TIF_RESTOREALL; - do_notify_resume(regs, ti_flags); - } - local_irq_disable(); - ti_flags = read_thread_flags(); - } - - if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && IS_ENABLED(CONFIG_PPC_FPU)) { - if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) && - unlikely((ti_flags & _TIF_RESTORE_TM))) { - restore_tm_state(regs); - } else { - unsigned long mathflags = MSR_FP; - - if (cpu_has_feature(CPU_FTR_VSX)) - mathflags |= MSR_VEC | MSR_VSX; - else if (cpu_has_feature(CPU_FTR_ALTIVEC)) - mathflags |= MSR_VEC; - - /* - * If userspace MSR has all available FP bits set, - * then they are live and no need to restore. If not, - * it means the regs were given up and restore_math - * may decide to restore them (to avoid taking an FP - * fault). - */ - if ((regs->msr & mathflags) != mathflags) - restore_math(regs); - } - } - - check_return_regs_valid(regs); - - user_enter_irqoff(); - if (!prep_irq_for_enabled_exit(true)) { - user_exit_irqoff(); - local_irq_enable(); - local_irq_disable(); - goto again; - } - -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM - local_paca->tm_scratch = regs->msr; -#endif - - booke_load_dbcr0(); - - account_cpu_user_exit(); - - /* Restore user access locks last */ - kuap_user_restore(regs); - - return ret; -} - /* * This should be called after a syscall returns, with r3 the return value * from the syscall. If this function returns non-zero, the system call @@ -267,17 +89,12 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3, long scv) { unsigned long ti_flags; - unsigned long ret = 0; bool is_not_scv = !IS_ENABLED(CONFIG_PPC_BOOK3S_64) || !scv; - CT_WARN_ON(ct_state() == CT_STATE_USER); - kuap_assert_locked(); regs->result = r3; - - /* Check whether the syscall is issued inside a restartable sequence */ - rseq_syscall(regs); + regs->exit_flags = 0; ti_flags = read_thread_flags(); @@ -290,7 +107,7 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3, if (unlikely(ti_flags & _TIF_PERSYSCALL_MASK)) { if (ti_flags & _TIF_RESTOREALL) - ret = _TIF_RESTOREALL; + regs->exit_flags = _TIF_RESTOREALL; else regs->gpr[3] = r3; clear_bits(_TIF_PERSYSCALL_MASK, ¤t_thread_info()->flags); @@ -299,18 +116,28 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3, } if (unlikely(ti_flags & _TIF_SYSCALL_DOTRACE)) { - do_syscall_trace_leave(regs); - ret |= _TIF_RESTOREALL; + regs->exit_flags |= _TIF_RESTOREALL; } - local_irq_disable(); - ret = interrupt_exit_user_prepare_main(ret, regs); + syscall_exit_to_user_mode(regs); + +again: + user_enter_irqoff(); + if (!prep_irq_for_enabled_exit(true)) { + user_exit_irqoff(); + local_irq_enable(); + local_irq_disable(); + goto again; + } + + /* Restore user access locks last */ + kuap_user_restore(regs); #ifdef CONFIG_PPC64 - regs->exit_result = ret; + regs->exit_result = regs->exit_flags; #endif - return ret; + return regs->exit_flags; } #ifdef CONFIG_PPC64 @@ -330,13 +157,16 @@ notrace unsigned long syscall_exit_restart(unsigned long r3, struct pt_regs *reg set_kuap(AMR_KUAP_BLOCKED); #endif - trace_hardirqs_off(); - user_exit_irqoff(); - account_cpu_user_entry(); - - BUG_ON(!user_mode(regs)); +again: + user_enter_irqoff(); + if (!prep_irq_for_enabled_exit(true)) { + user_exit_irqoff(); + local_irq_enable(); + local_irq_disable(); + goto again; + } - regs->exit_result = interrupt_exit_user_prepare_main(regs->exit_result, regs); + regs->exit_result |= regs->exit_flags; return regs->exit_result; } @@ -348,7 +178,6 @@ notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs) BUG_ON(regs_is_unrecoverable(regs)); BUG_ON(regs_irqs_disabled(regs)); - CT_WARN_ON(ct_state() == CT_STATE_USER); /* * We don't need to restore AMR on the way back to userspace for KUAP. @@ -357,8 +186,21 @@ notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs) kuap_assert_locked(); local_irq_disable(); + regs->exit_flags = 0; +again: + check_return_regs_valid(regs); + user_enter_irqoff(); + if (!prep_irq_for_enabled_exit(true)) { + user_exit_irqoff(); + local_irq_enable(); + local_irq_disable(); + goto again; + } + + /* Restore user access locks last */ + kuap_user_restore(regs); - ret = interrupt_exit_user_prepare_main(0, regs); + ret = regs->exit_flags; #ifdef CONFIG_PPC64 regs->exit_result = ret; @@ -400,13 +242,6 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs) /* Returning to a kernel context with local irqs enabled. */ WARN_ON_ONCE(!(regs->msr & MSR_EE)); again: - if (need_irq_preemption()) { - /* Return to preemptible kernel context */ - if (unlikely(read_thread_flags() & _TIF_NEED_RESCHED)) { - if (preempt_count() == 0) - preempt_schedule_irq(); - } - } check_return_regs_valid(regs); @@ -479,7 +314,6 @@ notrace unsigned long interrupt_exit_user_restart(struct pt_regs *regs) #endif trace_hardirqs_off(); - user_exit_irqoff(); account_cpu_user_entry(); BUG_ON(!user_mode(regs)); diff --git a/arch/powerpc/kernel/ptrace/ptrace.c b/arch/powerpc/kernel/ptrace/ptrace.c index 2134b6d155ff..f006a03a0211 100644 --- a/arch/powerpc/kernel/ptrace/ptrace.c +++ b/arch/powerpc/kernel/ptrace/ptrace.c @@ -21,9 +21,6 @@ #include <asm/switch_to.h> #include <asm/debug.h> -#define CREATE_TRACE_POINTS -#include <trace/events/syscalls.h> - #include "ptrace-decl.h" /* diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c index aa17e62f3754..9f1847b4742e 100644 --- a/arch/powerpc/kernel/signal.c +++ b/arch/powerpc/kernel/signal.c @@ -6,6 +6,7 @@ * Extracted from signal_32.c and signal_64.c */ +#include <linux/entry-common.h> #include <linux/resume_user_mode.h> #include <linux/signal.h> #include <linux/uprobes.h> @@ -368,3 +369,10 @@ void signal_fault(struct task_struct *tsk, struct pt_regs *regs, printk_ratelimited(regs->msr & MSR_64BIT ? fm64 : fm32, tsk->comm, task_pid_nr(tsk), where, ptr, regs->nip, regs->link); } + +void arch_do_signal_or_restart(struct pt_regs *regs) +{ + BUG_ON(regs != current->thread.regs); + regs->exit_flags |= _TIF_RESTOREALL; + do_signal(current); +} diff --git a/arch/powerpc/kernel/syscall.c b/arch/powerpc/kernel/syscall.c index 52d6e10eab22..a9da2af6efa8 100644 --- a/arch/powerpc/kernel/syscall.c +++ b/arch/powerpc/kernel/syscall.c @@ -3,6 +3,7 @@ #include <linux/compat.h> #include <linux/context_tracking.h> #include <linux/randomize_kstack.h> +#include <linux/entry-common.h> #include <asm/interrupt.h> #include <asm/kup.h> @@ -18,124 +19,10 @@ notrace long system_call_exception(struct pt_regs *regs, unsigned long r0) long ret; syscall_fn f; - kuap_lock(); - - if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) - BUG_ON(irq_soft_mask_return() != IRQS_ALL_DISABLED); - - trace_hardirqs_off(); /* finish reconciling */ - - CT_WARN_ON(ct_state() == CT_STATE_KERNEL); - user_exit_irqoff(); - add_random_kstack_offset(); + r0 = syscall_enter_from_user_mode(regs, r0); - BUG_ON(regs_is_unrecoverable(regs)); - BUG_ON(!user_mode(regs)); - BUG_ON(regs_irqs_disabled(regs)); - -#ifdef CONFIG_PPC_PKEY - if (mmu_has_feature(MMU_FTR_PKEY)) { - unsigned long amr, iamr; - bool flush_needed = false; - /* - * When entering from userspace we mostly have the AMR/IAMR - * different from kernel default values. Hence don't compare. - */ - amr = mfspr(SPRN_AMR); - iamr = mfspr(SPRN_IAMR); - regs->amr = amr; - regs->iamr = iamr; - if (mmu_has_feature(MMU_FTR_KUAP)) { - mtspr(SPRN_AMR, AMR_KUAP_BLOCKED); - flush_needed = true; - } - if (mmu_has_feature(MMU_FTR_BOOK3S_KUEP)) { - mtspr(SPRN_IAMR, AMR_KUEP_BLOCKED); - flush_needed = true; - } - if (flush_needed) - isync(); - } else -#endif - kuap_assert_locked(); - - booke_restore_dbcr0(); - - account_cpu_user_entry(); - - account_stolen_time(); - - /* - * This is not required for the syscall exit path, but makes the - * stack frame look nicer. If this was initialised in the first stack - * frame, or if the unwinder was taught the first stack frame always - * returns to user with IRQS_ENABLED, this store could be avoided! - */ - irq_soft_mask_regs_set_state(regs, IRQS_ENABLED); - - /* - * If system call is called with TM active, set _TIF_RESTOREALL to - * prevent RFSCV being used to return to userspace, because POWER9 - * TM implementation has problems with this instruction returning to - * transactional state. Final register values are not relevant because - * the transaction will be aborted upon return anyway. Or in the case - * of unsupported_scv SIGILL fault, the return state does not much - * matter because it's an edge case. - */ - if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) && - unlikely(MSR_TM_TRANSACTIONAL(regs->msr))) - set_bits(_TIF_RESTOREALL, ¤t_thread_info()->flags); - - /* - * If the system call was made with a transaction active, doom it and - * return without performing the system call. Unless it was an - * unsupported scv vector, in which case it's treated like an illegal - * instruction. - */ -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM - if (unlikely(MSR_TM_TRANSACTIONAL(regs->msr)) && - !trap_is_unsupported_scv(regs)) { - /* Enable TM in the kernel, and disable EE (for scv) */ - hard_irq_disable(); - mtmsr(mfmsr() | MSR_TM); - - /* tabort, this dooms the transaction, nothing else */ - asm volatile(".long 0x7c00071d | ((%0) << 16)" - :: "r"(TM_CAUSE_SYSCALL|TM_CAUSE_PERSISTENT)); - - /* - * Userspace will never see the return value. Execution will - * resume after the tbegin. of the aborted transaction with the - * checkpointed register state. A context switch could occur - * or signal delivered to the process before resuming the - * doomed transaction context, but that should all be handled - * as expected. - */ - return -ENOSYS; - } -#endif // CONFIG_PPC_TRANSACTIONAL_MEM - - local_irq_enable(); - - if (unlikely(read_thread_flags() & _TIF_SYSCALL_DOTRACE)) { - if (unlikely(trap_is_unsupported_scv(regs))) { - /* Unsupported scv vector */ - _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); - return regs->gpr[3]; - } - /* - * We use the return value of do_syscall_trace_enter() as the - * syscall number. If the syscall was rejected for any reason - * do_syscall_trace_enter() returns an invalid syscall number - * and the test against NR_syscalls will fail and the return - * value to be used is in regs->gpr[3]. - */ - r0 = do_syscall_trace_enter(regs); - if (unlikely(r0 >= NR_syscalls)) - return regs->gpr[3]; - - } else if (unlikely(r0 >= NR_syscalls)) { + if (unlikely(r0 >= NR_syscalls)) { if (unlikely(trap_is_unsupported_scv(regs))) { /* Unsupported scv vector */ _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); |