diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/verifier.c | 7 | ||||
| -rw-r--r-- | kernel/module/main.c | 10 | ||||
| -rw-r--r-- | kernel/power/console.c | 7 | ||||
| -rw-r--r-- | kernel/printk/nbcon.c | 63 | ||||
| -rw-r--r-- | kernel/rcu/tree.c | 2 | ||||
| -rw-r--r-- | kernel/rcu/tree.h | 14 | ||||
| -rw-r--r-- | kernel/rcu/tree_nocb.h | 5 | ||||
| -rw-r--r-- | kernel/rcu/tree_plugin.h | 44 | ||||
| -rw-r--r-- | kernel/sched/deadline.c | 4 | ||||
| -rw-r--r-- | kernel/sched/fair.c | 19 | ||||
| -rw-r--r-- | kernel/sched/rt.c | 6 |
11 files changed, 134 insertions, 47 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 531412c5103d..24ae8f33e5d7 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -400,7 +400,8 @@ static bool reg_not_null(const struct bpf_reg_state *reg) type == PTR_TO_MAP_KEY || type == PTR_TO_SOCK_COMMON || (type == PTR_TO_BTF_ID && is_trusted_reg(reg)) || - type == PTR_TO_MEM; + type == PTR_TO_MEM || + type == CONST_PTR_TO_MAP; } static struct btf_record *reg_btf_record(const struct bpf_reg_state *reg) @@ -15052,6 +15053,10 @@ static void regs_refine_cond_op(struct bpf_reg_state *reg1, struct bpf_reg_state if (!is_reg_const(reg2, is_jmp32)) break; val = reg_const_value(reg2, is_jmp32); + /* Forget the ranges before narrowing tnums, to avoid invariant + * violations if we're on a dead branch. + */ + __mark_reg_unbounded(reg1); if (is_jmp32) { t = tnum_and(tnum_subreg(reg1->var_off), tnum_const(~val)); reg1->var_off = tnum_with_subreg(reg1->var_off, t); diff --git a/kernel/module/main.c b/kernel/module/main.c index 6908062f4560..4511d0a4762a 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -703,14 +703,16 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user, struct module *mod; char name[MODULE_NAME_LEN]; char buf[MODULE_FLAGS_BUF_SIZE]; - int ret, forced = 0; + int ret, len, forced = 0; if (!capable(CAP_SYS_MODULE) || modules_disabled) return -EPERM; - if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) - return -EFAULT; - name[MODULE_NAME_LEN-1] = '\0'; + len = strncpy_from_user(name, name_user, MODULE_NAME_LEN); + if (len == 0 || len == MODULE_NAME_LEN) + return -ENOENT; + if (len < 0) + return len; audit_log_kern_module(name); diff --git a/kernel/power/console.c b/kernel/power/console.c index fcdf0e14a47d..19c48aa5355d 100644 --- a/kernel/power/console.c +++ b/kernel/power/console.c @@ -16,6 +16,7 @@ #define SUSPEND_CONSOLE (MAX_NR_CONSOLES-1) static int orig_fgconsole, orig_kmsg; +static bool vt_switch_done; static DEFINE_MUTEX(vt_switch_mutex); @@ -136,17 +137,21 @@ void pm_prepare_console(void) if (orig_fgconsole < 0) return; + vt_switch_done = true; + orig_kmsg = vt_kmsg_redirect(SUSPEND_CONSOLE); return; } void pm_restore_console(void) { - if (!pm_vt_switch()) + if (!pm_vt_switch() && !vt_switch_done) return; if (orig_fgconsole >= 0) { vt_move_to_console(orig_fgconsole, 0); vt_kmsg_redirect(orig_kmsg); } + + vt_switch_done = false; } diff --git a/kernel/printk/nbcon.c b/kernel/printk/nbcon.c index fd12efcc4aed..e7a3af81b173 100644 --- a/kernel/printk/nbcon.c +++ b/kernel/printk/nbcon.c @@ -214,8 +214,9 @@ static void nbcon_seq_try_update(struct nbcon_context *ctxt, u64 new_seq) /** * nbcon_context_try_acquire_direct - Try to acquire directly - * @ctxt: The context of the caller - * @cur: The current console state + * @ctxt: The context of the caller + * @cur: The current console state + * @is_reacquire: This acquire is a reacquire * * Acquire the console when it is released. Also acquire the console when * the current owner has a lower priority and the console is in a safe state. @@ -225,17 +226,17 @@ static void nbcon_seq_try_update(struct nbcon_context *ctxt, u64 new_seq) * * Errors: * - * -EPERM: A panic is in progress and this is not the panic CPU. - * Or the current owner or waiter has the same or higher - * priority. No acquire method can be successful in - * this case. + * -EPERM: A panic is in progress and this is neither the panic + * CPU nor is this a reacquire. Or the current owner or + * waiter has the same or higher priority. No acquire + * method can be successful in these cases. * * -EBUSY: The current owner has a lower priority but the console * in an unsafe state. The caller should try using * the handover acquire method. */ static int nbcon_context_try_acquire_direct(struct nbcon_context *ctxt, - struct nbcon_state *cur) + struct nbcon_state *cur, bool is_reacquire) { unsigned int cpu = smp_processor_id(); struct console *con = ctxt->console; @@ -243,14 +244,20 @@ static int nbcon_context_try_acquire_direct(struct nbcon_context *ctxt, do { /* - * Panic does not imply that the console is owned. However, it - * is critical that non-panic CPUs during panic are unable to - * acquire ownership in order to satisfy the assumptions of - * nbcon_waiter_matches(). In particular, the assumption that - * lower priorities are ignored during panic. + * Panic does not imply that the console is owned. However, + * since all non-panic CPUs are stopped during panic(), it + * is safer to have them avoid gaining console ownership. + * + * If this acquire is a reacquire (and an unsafe takeover + * has not previously occurred) then it is allowed to attempt + * a direct acquire in panic. This gives console drivers an + * opportunity to perform any necessary cleanup if they were + * interrupted by the panic CPU while printing. */ - if (other_cpu_in_panic()) + if (other_cpu_in_panic() && + (!is_reacquire || cur->unsafe_takeover)) { return -EPERM; + } if (ctxt->prio <= cur->prio || ctxt->prio <= cur->req_prio) return -EPERM; @@ -301,8 +308,9 @@ static bool nbcon_waiter_matches(struct nbcon_state *cur, int expected_prio) * Event #1 implies this context is EMERGENCY. * Event #2 implies the new context is PANIC. * Event #3 occurs when panic() has flushed the console. - * Events #4 and #5 are not possible due to the other_cpu_in_panic() - * check in nbcon_context_try_acquire_direct(). + * Event #4 occurs when a non-panic CPU reacquires. + * Event #5 is not possible due to the other_cpu_in_panic() check + * in nbcon_context_try_acquire_handover(). */ return (cur->req_prio == expected_prio); @@ -431,6 +439,16 @@ static int nbcon_context_try_acquire_handover(struct nbcon_context *ctxt, WARN_ON_ONCE(ctxt->prio <= cur->prio || ctxt->prio <= cur->req_prio); WARN_ON_ONCE(!cur->unsafe); + /* + * Panic does not imply that the console is owned. However, it + * is critical that non-panic CPUs during panic are unable to + * wait for a handover in order to satisfy the assumptions of + * nbcon_waiter_matches(). In particular, the assumption that + * lower priorities are ignored during panic. + */ + if (other_cpu_in_panic()) + return -EPERM; + /* Handover is not possible on the same CPU. */ if (cur->cpu == cpu) return -EBUSY; @@ -558,7 +576,8 @@ static struct printk_buffers panic_nbcon_pbufs; /** * nbcon_context_try_acquire - Try to acquire nbcon console - * @ctxt: The context of the caller + * @ctxt: The context of the caller + * @is_reacquire: This acquire is a reacquire * * Context: Under @ctxt->con->device_lock() or local_irq_save(). * Return: True if the console was acquired. False otherwise. @@ -568,7 +587,7 @@ static struct printk_buffers panic_nbcon_pbufs; * in an unsafe state. Otherwise, on success the caller may assume * the console is not in an unsafe state. */ -static bool nbcon_context_try_acquire(struct nbcon_context *ctxt) +static bool nbcon_context_try_acquire(struct nbcon_context *ctxt, bool is_reacquire) { unsigned int cpu = smp_processor_id(); struct console *con = ctxt->console; @@ -577,7 +596,7 @@ static bool nbcon_context_try_acquire(struct nbcon_context *ctxt) nbcon_state_read(con, &cur); try_again: - err = nbcon_context_try_acquire_direct(ctxt, &cur); + err = nbcon_context_try_acquire_direct(ctxt, &cur, is_reacquire); if (err != -EBUSY) goto out; @@ -913,7 +932,7 @@ void nbcon_reacquire_nobuf(struct nbcon_write_context *wctxt) { struct nbcon_context *ctxt = &ACCESS_PRIVATE(wctxt, ctxt); - while (!nbcon_context_try_acquire(ctxt)) + while (!nbcon_context_try_acquire(ctxt, true)) cpu_relax(); nbcon_write_context_set_buf(wctxt, NULL, 0); @@ -1101,7 +1120,7 @@ static bool nbcon_emit_one(struct nbcon_write_context *wctxt, bool use_atomic) cant_migrate(); } - if (!nbcon_context_try_acquire(ctxt)) + if (!nbcon_context_try_acquire(ctxt, false)) goto out; /* @@ -1486,7 +1505,7 @@ static int __nbcon_atomic_flush_pending_con(struct console *con, u64 stop_seq, ctxt->prio = nbcon_get_default_prio(); ctxt->allow_unsafe_takeover = allow_unsafe_takeover; - if (!nbcon_context_try_acquire(ctxt)) + if (!nbcon_context_try_acquire(ctxt, false)) return -EPERM; while (nbcon_seq_read(con) < stop_seq) { @@ -1762,7 +1781,7 @@ bool nbcon_device_try_acquire(struct console *con) ctxt->console = con; ctxt->prio = NBCON_PRIO_NORMAL; - if (!nbcon_context_try_acquire(ctxt)) + if (!nbcon_context_try_acquire(ctxt, false)) return false; if (!nbcon_context_enter_unsafe(ctxt)) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 552464dcffe2..7b073b8b5e91 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -5027,6 +5027,8 @@ int rcutree_prepare_cpu(unsigned int cpu) rdp->rcu_iw_gp_seq = rdp->gp_seq - 1; trace_rcu_grace_period(rcu_state.name, rdp->gp_seq, TPS("cpuonl")); raw_spin_unlock_irqrestore_rcu_node(rnp, flags); + + rcu_preempt_deferred_qs_init(rdp); rcu_spawn_rnp_kthreads(rnp); rcu_spawn_cpu_nocb_kthread(cpu); ASSERT_EXCLUSIVE_WRITER(rcu_state.n_online_cpus); diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index 1bba2225e744..8ba04b179416 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -174,6 +174,17 @@ struct rcu_snap_record { unsigned long jiffies; /* Track jiffies value */ }; +/* + * An IRQ work (deferred_qs_iw) is used by RCU to get the scheduler's attention. + * to report quiescent states at the soonest possible time. + * The request can be in one of the following states: + * - DEFER_QS_IDLE: An IRQ work is yet to be scheduled. + * - DEFER_QS_PENDING: An IRQ work was scheduled but either not yet run, or it + * ran and we still haven't reported a quiescent state. + */ +#define DEFER_QS_IDLE 0 +#define DEFER_QS_PENDING 1 + /* Per-CPU data for read-copy update. */ struct rcu_data { /* 1) quiescent-state and grace-period handling : */ @@ -191,7 +202,7 @@ struct rcu_data { /* during and after the last grace */ /* period it is aware of. */ struct irq_work defer_qs_iw; /* Obtain later scheduler attention. */ - bool defer_qs_iw_pending; /* Scheduler attention pending? */ + int defer_qs_iw_pending; /* Scheduler attention pending? */ struct work_struct strict_work; /* Schedule readers for strict GPs. */ /* 2) batch handling */ @@ -476,6 +487,7 @@ static int rcu_print_task_exp_stall(struct rcu_node *rnp); static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp); static void rcu_flavor_sched_clock_irq(int user); static void dump_blkd_tasks(struct rcu_node *rnp, int ncheck); +static void rcu_preempt_deferred_qs_init(struct rcu_data *rdp); static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags); static void rcu_preempt_boost_start_gp(struct rcu_node *rnp); static bool rcu_is_callbacks_kthread(struct rcu_data *rdp); diff --git a/kernel/rcu/tree_nocb.h b/kernel/rcu/tree_nocb.h index 2ad3a88623a7..a1a5942d7017 100644 --- a/kernel/rcu/tree_nocb.h +++ b/kernel/rcu/tree_nocb.h @@ -1152,7 +1152,6 @@ static bool rcu_nocb_rdp_offload_wait_cond(struct rcu_data *rdp) static int rcu_nocb_rdp_offload(struct rcu_data *rdp) { int wake_gp; - struct rcu_data *rdp_gp = rdp->nocb_gp_rdp; WARN_ON_ONCE(cpu_online(rdp->cpu)); /* @@ -1162,7 +1161,7 @@ static int rcu_nocb_rdp_offload(struct rcu_data *rdp) if (!rdp->nocb_gp_rdp) return -EINVAL; - if (WARN_ON_ONCE(!rdp_gp->nocb_gp_kthread)) + if (WARN_ON_ONCE(!rdp->nocb_gp_kthread)) return -EINVAL; pr_info("Offloading %d\n", rdp->cpu); @@ -1172,7 +1171,7 @@ static int rcu_nocb_rdp_offload(struct rcu_data *rdp) wake_gp = rcu_nocb_queue_toggle_rdp(rdp); if (wake_gp) - wake_up_process(rdp_gp->nocb_gp_kthread); + wake_up_process(rdp->nocb_gp_kthread); swait_event_exclusive(rdp->nocb_state_wq, rcu_nocb_rdp_offload_wait_cond(rdp)); diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 304e3405e6ec..2d865b2096be 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -485,13 +485,16 @@ rcu_preempt_deferred_qs_irqrestore(struct task_struct *t, unsigned long flags) struct rcu_node *rnp; union rcu_special special; + rdp = this_cpu_ptr(&rcu_data); + if (rdp->defer_qs_iw_pending == DEFER_QS_PENDING) + rdp->defer_qs_iw_pending = DEFER_QS_IDLE; + /* * If RCU core is waiting for this CPU to exit its critical section, * report the fact that it has exited. Because irqs are disabled, * t->rcu_read_unlock_special cannot change. */ special = t->rcu_read_unlock_special; - rdp = this_cpu_ptr(&rcu_data); if (!special.s && !rdp->cpu_no_qs.b.exp) { local_irq_restore(flags); return; @@ -623,10 +626,29 @@ notrace void rcu_preempt_deferred_qs(struct task_struct *t) */ static void rcu_preempt_deferred_qs_handler(struct irq_work *iwp) { + unsigned long flags; struct rcu_data *rdp; rdp = container_of(iwp, struct rcu_data, defer_qs_iw); - rdp->defer_qs_iw_pending = false; + local_irq_save(flags); + + /* + * If the IRQ work handler happens to run in the middle of RCU read-side + * critical section, it could be ineffective in getting the scheduler's + * attention to report a deferred quiescent state (the whole point of the + * IRQ work). For this reason, requeue the IRQ work. + * + * Basically, we want to avoid following situation: + * 1. rcu_read_unlock() queues IRQ work (state -> DEFER_QS_PENDING) + * 2. CPU enters new rcu_read_lock() + * 3. IRQ work runs but cannot report QS due to rcu_preempt_depth() > 0 + * 4. rcu_read_unlock() does not re-queue work (state still PENDING) + * 5. Deferred QS reporting does not happen. + */ + if (rcu_preempt_depth() > 0) + WRITE_ONCE(rdp->defer_qs_iw_pending, DEFER_QS_IDLE); + + local_irq_restore(flags); } /* @@ -672,17 +694,11 @@ static void rcu_read_unlock_special(struct task_struct *t) set_tsk_need_resched(current); set_preempt_need_resched(); if (IS_ENABLED(CONFIG_IRQ_WORK) && irqs_were_disabled && - expboost && !rdp->defer_qs_iw_pending && cpu_online(rdp->cpu)) { + expboost && rdp->defer_qs_iw_pending != DEFER_QS_PENDING && + cpu_online(rdp->cpu)) { // Get scheduler to re-evaluate and call hooks. // If !IRQ_WORK, FQS scan will eventually IPI. - if (IS_ENABLED(CONFIG_RCU_STRICT_GRACE_PERIOD) && - IS_ENABLED(CONFIG_PREEMPT_RT)) - rdp->defer_qs_iw = IRQ_WORK_INIT_HARD( - rcu_preempt_deferred_qs_handler); - else - init_irq_work(&rdp->defer_qs_iw, - rcu_preempt_deferred_qs_handler); - rdp->defer_qs_iw_pending = true; + rdp->defer_qs_iw_pending = DEFER_QS_PENDING; irq_work_queue_on(&rdp->defer_qs_iw, rdp->cpu); } } @@ -821,6 +837,10 @@ dump_blkd_tasks(struct rcu_node *rnp, int ncheck) } } +static void rcu_preempt_deferred_qs_init(struct rcu_data *rdp) +{ + rdp->defer_qs_iw = IRQ_WORK_INIT_HARD(rcu_preempt_deferred_qs_handler); +} #else /* #ifdef CONFIG_PREEMPT_RCU */ /* @@ -1020,6 +1040,8 @@ dump_blkd_tasks(struct rcu_node *rnp, int ncheck) WARN_ON_ONCE(!list_empty(&rnp->blkd_tasks)); } +static void rcu_preempt_deferred_qs_init(struct rcu_data *rdp) { } + #endif /* #else #ifdef CONFIG_PREEMPT_RCU */ /* diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 0a47e5155897..53e3670fbb1e 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -3227,6 +3227,9 @@ void sched_dl_do_global(void) if (global_rt_runtime() != RUNTIME_INF) new_bw = to_ratio(global_rt_period(), global_rt_runtime()); + for_each_possible_cpu(cpu) + init_dl_rq_bw_ratio(&cpu_rq(cpu)->dl); + for_each_possible_cpu(cpu) { rcu_read_lock_sched(); @@ -3242,7 +3245,6 @@ void sched_dl_do_global(void) raw_spin_unlock_irqrestore(&dl_b->lock, flags); rcu_read_unlock_sched(); - init_dl_rq_bw_ratio(&cpu_rq(cpu)->dl); } } diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 7280ed04c96c..af61769b1d50 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -12220,8 +12220,14 @@ static inline bool update_newidle_cost(struct sched_domain *sd, u64 cost) /* * Track max cost of a domain to make sure to not delay the * next wakeup on the CPU. + * + * sched_balance_newidle() bumps the cost whenever newidle + * balance fails, and we don't want things to grow out of + * control. Use the sysctl_sched_migration_cost as the upper + * limit, plus a litle extra to avoid off by ones. */ - sd->max_newidle_lb_cost = cost; + sd->max_newidle_lb_cost = + min(cost, sysctl_sched_migration_cost + 200); sd->last_decay_max_lb_cost = jiffies; } else if (time_after(jiffies, sd->last_decay_max_lb_cost + HZ)) { /* @@ -12926,10 +12932,17 @@ static int sched_balance_newidle(struct rq *this_rq, struct rq_flags *rf) t1 = sched_clock_cpu(this_cpu); domain_cost = t1 - t0; - update_newidle_cost(sd, domain_cost); - curr_cost += domain_cost; t0 = t1; + + /* + * Failing newidle means it is not effective; + * bump the cost so we end up doing less of it. + */ + if (!pulled_task) + domain_cost = (3 * sd->max_newidle_lb_cost) / 2; + + update_newidle_cost(sd, domain_cost); } /* diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 172c588de542..6ad6717084ed 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2951,6 +2951,12 @@ undo: } mutex_unlock(&mutex); + /* + * After changing maximum available bandwidth for DEADLINE, we need to + * recompute per root domain and per cpus variables accordingly. + */ + rebuild_sched_domains(); + return ret; } |