diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cred.c | 16 | ||||
| -rw-r--r-- | kernel/perf_event.c | 260 | ||||
| -rw-r--r-- | kernel/sched.c | 29 | ||||
| -rw-r--r-- | kernel/timer.c | 6 | ||||
| -rw-r--r-- | kernel/trace/trace_kprobe.c | 111 | ||||
| -rw-r--r-- | kernel/watchdog.c | 10 |
6 files changed, 301 insertions, 131 deletions
diff --git a/kernel/cred.c b/kernel/cred.c index 6a1aa00..3a9d6dd 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -252,13 +252,13 @@ struct cred *cred_alloc_blank(void) #endif atomic_set(&new->usage, 1); +#ifdef CONFIG_DEBUG_CREDENTIALS + new->magic = CRED_MAGIC; +#endif if (security_cred_alloc_blank(new, GFP_KERNEL) < 0) goto error; -#ifdef CONFIG_DEBUG_CREDENTIALS - new->magic = CRED_MAGIC; -#endif return new; error: @@ -657,6 +657,8 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon) validate_creds(old); *new = *old; + atomic_set(&new->usage, 1); + set_cred_subscribers(new, 0); get_uid(new->user); get_group_info(new->group_info); @@ -674,8 +676,6 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon) if (security_prepare_creds(new, old, GFP_KERNEL) < 0) goto error; - atomic_set(&new->usage, 1); - set_cred_subscribers(new, 0); put_cred(old); validate_creds(new); return new; @@ -748,7 +748,11 @@ bool creds_are_invalid(const struct cred *cred) if (cred->magic != CRED_MAGIC) return true; #ifdef CONFIG_SECURITY_SELINUX - if (selinux_is_enabled()) { + /* + * cred->security == NULL if security_cred_alloc_blank() or + * security_prepare_creds() returned an error. + */ + if (selinux_is_enabled() && cred->security) { if ((unsigned long) cred->security < PAGE_SIZE) return true; if ((*(u32 *)cred->security & 0xffffff00) == diff --git a/kernel/perf_event.c b/kernel/perf_event.c index 999835b..a353a4d 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -38,6 +38,79 @@ #include <asm/irq_regs.h> +struct remote_function_call { + struct task_struct *p; + int (*func)(void *info); + void *info; + int ret; +}; + +static void remote_function(void *data) +{ + struct remote_function_call *tfc = data; + struct task_struct *p = tfc->p; + + if (p) { + tfc->ret = -EAGAIN; + if (task_cpu(p) != smp_processor_id() || !task_curr(p)) + return; + } + + tfc->ret = tfc->func(tfc->info); +} + +/** + * task_function_call - call a function on the cpu on which a task runs + * @p: the task to evaluate + * @func: the function to be called + * @info: the function call argument + * + * Calls the function @func when the task is currently running. This might + * be on the current CPU, which just calls the function directly + * + * returns: @func return value, or + * -ESRCH - when the process isn't running + * -EAGAIN - when the process moved away + */ +static int +task_function_call(struct task_struct *p, int (*func) (void *info), void *info) +{ + struct remote_function_call data = { + .p = p, + .func = func, + .info = info, + .ret = -ESRCH, /* No such (running) process */ + }; + + if (task_curr(p)) + smp_call_function_single(task_cpu(p), remote_function, &data, 1); + + return data.ret; +} + +/** + * cpu_function_call - call a function on the cpu + * @func: the function to be called + * @info: the function call argument + * + * Calls the function @func on the remote cpu. + * + * returns: @func return value or -ENXIO when the cpu is offline + */ +static int cpu_function_call(int cpu, int (*func) (void *info), void *info) +{ + struct remote_function_call data = { + .p = NULL, + .func = func, + .info = info, + .ret = -ENXIO, /* No such CPU */ + }; + + smp_call_function_single(cpu, remote_function, &data, 1); + + return data.ret; +} + enum event_type_t { EVENT_FLEXIBLE = 0x1, EVENT_PINNED = 0x2, @@ -254,7 +327,6 @@ static void perf_unpin_context(struct perf_event_context *ctx) raw_spin_lock_irqsave(&ctx->lock, flags); --ctx->pin_count; raw_spin_unlock_irqrestore(&ctx->lock, flags); - put_ctx(ctx); } /* @@ -618,35 +690,24 @@ __get_cpu_context(struct perf_event_context *ctx) * We disable the event on the hardware level first. After that we * remove it from the context list. */ -static void __perf_event_remove_from_context(void *info) +static int __perf_remove_from_context(void *info) { struct perf_event *event = info; struct perf_event_context *ctx = event->ctx; struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); - /* - * If this is a task context, we need to check whether it is - * the current task context of this cpu. If not it has been - * scheduled out before the smp call arrived. - */ - if (ctx->task && cpuctx->task_ctx != ctx) - return; - raw_spin_lock(&ctx->lock); - event_sched_out(event, cpuctx, ctx); - list_del_event(event, ctx); - raw_spin_unlock(&ctx->lock); + + return 0; } /* * Remove the event from a task's (or a CPU's) list of events. * - * Must be called with ctx->mutex held. - * * CPU events are removed with a smp call. For task events we only * call when the task is on a CPU. * @@ -657,49 +718,48 @@ static void __perf_event_remove_from_context(void *info) * When called from perf_event_exit_task, it's OK because the * context has been detached from its task. */ -static void perf_event_remove_from_context(struct perf_event *event) +static void perf_remove_from_context(struct perf_event *event) { struct perf_event_context *ctx = event->ctx; struct task_struct *task = ctx->task; + lockdep_assert_held(&ctx->mutex); + if (!task) { /* * Per cpu events are removed via an smp call and * the removal is always successful. */ - smp_call_function_single(event->cpu, - __perf_event_remove_from_context, - event, 1); + cpu_function_call(event->cpu, __perf_remove_from_context, event); return; } retry: - task_oncpu_function_call(task, __perf_event_remove_from_context, - event); + if (!task_function_call(task, __perf_remove_from_context, event)) + return; raw_spin_lock_irq(&ctx->lock); /* - * If the context is active we need to retry the smp call. + * If we failed to find a running task, but find the context active now + * that we've acquired the ctx->lock, retry. */ - if (ctx->nr_active && !list_empty(&event->group_entry)) { + if (ctx->is_active) { raw_spin_unlock_irq(&ctx->lock); goto retry; } /* - * The lock prevents that this context is scheduled in so we - * can remove the event safely, if the call above did not - * succeed. + * Since the task isn't running, its safe to remove the event, us + * holding the ctx->lock ensures the task won't get scheduled in. */ - if (!list_empty(&event->group_entry)) - list_del_event(event, ctx); + list_del_event(event, ctx); raw_spin_unlock_irq(&ctx->lock); } /* * Cross CPU call to disable a performance event */ -static void __perf_event_disable(void *info) +static int __perf_event_disable(void *info) { struct perf_event *event = info; struct perf_event_context *ctx = event->ctx; @@ -708,9 +768,12 @@ static void __perf_event_disable(void *info) /* * If this is a per-task event, need to check whether this * event's task is the current task on this cpu. + * + * Can trigger due to concurrent perf_event_context_sched_out() + * flipping contexts around. */ if (ctx->task && cpuctx->task_ctx != ctx) - return; + return -EINVAL; raw_spin_lock(&ctx->lock); @@ -729,6 +792,8 @@ static void __perf_event_disable(void *info) } raw_spin_unlock(&ctx->lock); + + return 0; } /* @@ -753,13 +818,13 @@ void perf_event_disable(struct perf_event *event) /* * Disable the event on the cpu that it's on */ - smp_call_function_single(event->cpu, __perf_event_disable, - event, 1); + cpu_function_call(event->cpu, __perf_event_disable, event); return; } retry: - task_oncpu_function_call(task, __perf_event_disable, event); + if (!task_function_call(task, __perf_event_disable, event)) + return; raw_spin_lock_irq(&ctx->lock); /* @@ -767,6 +832,11 @@ retry: */ if (event->state == PERF_EVENT_STATE_ACTIVE) { raw_spin_unlock_irq(&ctx->lock); + /* + * Reload the task pointer, it might have been changed by + * a concurrent perf_event_context_sched_out(). + */ + task = ctx->task; goto retry; } @@ -778,7 +848,6 @@ retry: update_group_times(event); event->state = PERF_EVENT_STATE_OFF; } - raw_spin_unlock_irq(&ctx->lock); } @@ -928,12 +997,14 @@ static void add_event_to_ctx(struct perf_event *event, event->tstamp_stopped = tstamp; } +static void perf_event_context_sched_in(struct perf_event_context *ctx); + /* * Cross CPU call to install and enable a performance event * * Must be called with ctx->mutex held */ -static void __perf_install_in_context(void *info) +static int __perf_install_in_context(void *info) { struct perf_event *event = info; struct perf_event_context *ctx = event->ctx; @@ -942,17 +1013,12 @@ static void __perf_install_in_context(void *info) int err; /* - * If this is a task context, we need to check whether it is - * the current task context of this cpu. If not it has been - * scheduled out before the smp call arrived. - * Or possibly this is the right context but it isn't - * on this cpu because it had no events. + * In case we're installing a new context to an already running task, + * could also happen before perf_event_task_sched_in() on architectures + * which do context switches with IRQs enabled. */ - if (ctx->task && cpuctx->task_ctx != ctx) { - if (cpuctx->task_ctx || ctx->task != current) - return; - cpuctx->task_ctx = ctx; - } + if (ctx->task && !cpuctx->task_ctx) + perf_event_context_sched_in(ctx); raw_spin_lock(&ctx->lock); ctx->is_active = 1; @@ -997,6 +1063,8 @@ static void __perf_install_in_context(void *info) unlock: raw_spin_unlock(&ctx->lock); + + return 0; } /* @@ -1008,8 +1076,6 @@ unlock: * If the event is attached to a task which is on a CPU we use a smp * call to enable it in the task context. The task might have been * scheduled away, but we check this in the smp call again. - * - * Must be called with ctx->mutex held. */ static void perf_install_in_context(struct perf_event_context *ctx, @@ -1018,6 +1084,8 @@ perf_install_in_context(struct perf_event_context *ctx, { struct task_struct *task = ctx->task; + lockdep_assert_held(&ctx->mutex); + event->ctx = ctx; if (!task) { @@ -1025,31 +1093,29 @@ perf_install_in_context(struct perf_event_context *ctx, * Per cpu events are installed via an smp call and * the install is always successful. */ - smp_call_function_single(cpu, __perf_install_in_context, - event, 1); + cpu_function_call(cpu, __perf_install_in_context, event); return; } retry: - task_oncpu_function_call(task, __perf_install_in_context, - event); + if (!task_function_call(task, __perf_install_in_context, event)) + return; raw_spin_lock_irq(&ctx->lock); /* - * we need to retry the smp call. + * If we failed to find a running task, but find the context active now + * that we've acquired the ctx->lock, retry. */ - if (ctx->is_active && list_empty(&event->group_entry)) { + if (ctx->is_active) { raw_spin_unlock_irq(&ctx->lock); goto retry; } /* - * The lock prevents that this context is scheduled in so we - * can add the event safely, if it the call above did not - * succeed. + * Since the task isn't running, its safe to add the event, us holding + * the ctx->lock ensures the task won't get scheduled in. */ - if (list_empty(&event->group_entry)) - add_event_to_ctx(event, ctx); + add_event_to_ctx(event, ctx); raw_spin_unlock_irq(&ctx->lock); } @@ -1078,7 +1144,7 @@ static void __perf_event_mark_enabled(struct perf_event *event, /* * Cross CPU call to enable a performance event */ -static void __perf_event_enable(void *info) +static int __perf_event_enable(void *info) { struct perf_event *event = info; struct perf_event_context *ctx = event->ctx; @@ -1086,18 +1152,10 @@ static void __perf_event_enable(void *info) struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); int err; - /* - * If this is a per-task event, need to check whether this - * event's task is the current task on this cpu. - */ - if (ctx->task && cpuctx->task_ctx != ctx) { - if (cpuctx->task_ctx || ctx->task != current) - return; - cpuctx->task_ctx = ctx; - } + if (WARN_ON_ONCE(!ctx->is_active)) + return -EINVAL; raw_spin_lock(&ctx->lock); - ctx->is_active = 1; update_context_time(ctx); if (event->state >= PERF_EVENT_STATE_INACTIVE) @@ -1138,6 +1196,8 @@ static void __perf_event_enable(void *info) unlock: raw_spin_unlock(&ctx->lock); + + return 0; } /* @@ -1158,8 +1218,7 @@ void perf_event_enable(struct perf_event *event) /* * Enable the event on the cpu that it's on */ - smp_call_function_single(event->cpu, __perf_event_enable, - event, 1); + cpu_function_call(event->cpu, __perf_event_enable, event); return; } @@ -1178,8 +1237,15 @@ void perf_event_enable(struct perf_event *event) event->state = PERF_EVENT_STATE_OFF; retry: + if (!ctx->is_active) { + __perf_event_mark_enabled(event, ctx); + goto out; + } + raw_spin_unlock_irq(&ctx->lock); - task_oncpu_function_call(task, __perf_event_enable, event); + + if (!task_function_call(task, __perf_event_enable, event)) + return; raw_spin_lock_irq(&ctx->lock); @@ -1187,15 +1253,14 @@ retry: * If the context is active and the event is still off, * we need to retry the cross-call. */ - if (ctx->is_active && event->state == PERF_EVENT_STATE_OFF) + if (ctx->is_active && event->state == PERF_EVENT_STATE_OFF) { + /* + * task could have been flipped by a concurrent + * perf_event_context_sched_out() + */ + task = ctx->task; goto retry; - - /* - * Since we have the lock this context can't be scheduled - * in, so we can change the state safely. - */ - if (event->state == PERF_EVENT_STATE_OFF) - __perf_event_mark_enabled(event, ctx); + } out: raw_spin_unlock_irq(&ctx->lock); @@ -1339,8 +1404,8 @@ static void perf_event_sync_stat(struct perf_event_context *ctx, } } -void perf_event_context_sched_out(struct task_struct *task, int ctxn, - struct task_struct *next) +static void perf_event_context_sched_out(struct task_struct *task, int ctxn, + struct task_struct *next) { struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; struct perf_event_context *next_ctx; @@ -1533,7 +1598,7 @@ static void task_ctx_sched_in(struct perf_event_context *ctx, { struct perf_cpu_context *cpuctx; - cpuctx = __get_cpu_context(ctx); + cpuctx = __get_cpu_context(ctx); if (cpuctx->task_ctx == ctx) return; @@ -1541,7 +1606,7 @@ static void task_ctx_sched_in(struct perf_event_context *ctx, cpuctx->task_ctx = ctx; } -void perf_event_context_sched_in(struct perf_event_context *ctx) +static void perf_event_context_sched_in(struct perf_event_context *ctx) { struct perf_cpu_context *cpuctx; @@ -1627,7 +1692,7 @@ static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) * Reduce accuracy by one bit such that @a and @b converge * to a similar magnitude. */ -#define REDUCE_FLS(a, b) \ +#define REDUCE_FLS(a, b) \ do { \ if (a##_fls > b##_fls) { \ a >>= 1; \ @@ -2213,6 +2278,9 @@ errout: } +/* + * Returns a matching context with refcount and pincount. + */ static struct perf_event_context * find_get_context(struct pmu *pmu, struct task_struct *task, int cpu) { @@ -2237,6 +2305,7 @@ find_get_context(struct pmu *pmu, struct task_struct *task, int cpu) cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); ctx = &cpuctx->ctx; get_ctx(ctx); + ++ctx->pin_count; return ctx; } @@ -2250,6 +2319,7 @@ retry: ctx = perf_lock_task_context(task, ctxn, &flags); if (ctx) { unclone_ctx(ctx); + ++ctx->pin_count; raw_spin_unlock_irqrestore(&ctx->lock, flags); } @@ -2271,8 +2341,10 @@ retry: err = -ESRCH; else if (task->perf_event_ctxp[ctxn]) err = -EAGAIN; - else + else { + ++ctx->pin_count; rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); + } mutex_unlock(&task->perf_event_mutex); if (unlikely(err)) { @@ -5950,10 +6022,10 @@ SYSCALL_DEFINE5(perf_event_open, struct perf_event_context *gctx = group_leader->ctx; mutex_lock(&gctx->mutex); - perf_event_remove_from_context(group_leader); + perf_remove_from_context(group_leader); list_for_each_entry(sibling, &group_leader->sibling_list, group_entry) { - perf_event_remove_from_context(sibling); + perf_remove_from_context(sibling); put_ctx(gctx); } mutex_unlock(&gctx->mutex); @@ -5976,6 +6048,7 @@ SYSCALL_DEFINE5(perf_event_open, perf_install_in_context(ctx, event, cpu); ++ctx->generation; + perf_unpin_context(ctx); mutex_unlock(&ctx->mutex); event->owner = current; @@ -6001,6 +6074,7 @@ SYSCALL_DEFINE5(perf_event_open, return event_fd; err_context: + perf_unpin_context(ctx); put_ctx(ctx); err_alloc: free_event(event); @@ -6051,6 +6125,7 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, mutex_lock(&ctx->mutex); perf_install_in_context(ctx, event, cpu); ++ctx->generation; + perf_unpin_context(ctx); mutex_unlock(&ctx->mutex); return event; @@ -6104,7 +6179,7 @@ __perf_event_exit_task(struct perf_event *child_event, { struct perf_event *parent_event; - perf_event_remove_from_context(child_event); + perf_remove_from_context(child_event); parent_event = child_event->parent; /* @@ -6411,7 +6486,7 @@ inherit_task_group(struct perf_event *event, struct task_struct *parent, return 0; } - child_ctx = child->perf_event_ctxp[ctxn]; + child_ctx = child->perf_event_ctxp[ctxn]; if (!child_ctx) { /* * This is executed from the parent task context, so @@ -6526,6 +6601,7 @@ int perf_event_init_context(struct task_struct *child, int ctxn) mutex_unlock(&parent_ctx->mutex); perf_unpin_context(parent_ctx); + put_ctx(parent_ctx); return ret; } @@ -6595,9 +6671,9 @@ static void __perf_event_exit_context(void *__info) perf_pmu_rotate_stop(ctx->pmu); list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, group_entry) - __perf_event_remove_from_context(event); + __perf_remove_from_context(event); list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, group_entry) - __perf_event_remove_from_context(event); + __perf_remove_from_context(event); } static void perf_event_exit_cpu_context(int cpu) diff --git a/kernel/sched.c b/kernel/sched.c index fbe86cb..e142e92 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2265,27 +2265,6 @@ void kick_process(struct task_struct *p) EXPORT_SYMBOL_GPL(kick_process); #endif /* CONFIG_SMP */ -/** - * task_oncpu_function_call - call a function on the cpu on which a task runs - * @p: the task to evaluate - * @func: the function to be called - * @info: the function call argument - * - * Calls the function @func when the task is currently running. This might - * be on the current CPU, which just calls the function directly - */ -void task_oncpu_function_call(struct task_struct *p, - void (*func) (void *info), void *info) -{ - int cpu; - - preempt_disable(); - cpu = task_cpu(p); - if (task_curr(p)) - smp_call_function_single(cpu, func, info, 1); - preempt_enable(); -} - #ifdef CONFIG_SMP /* * ->cpus_allowed is protected by either TASK_WAKING or rq->lock held. @@ -2776,9 +2755,12 @@ static inline void prepare_task_switch(struct rq *rq, struct task_struct *prev, struct task_struct *next) { + sched_info_switch(prev, next); + perf_event_task_sched_out(prev, next); fire_sched_out_preempt_notifiers(prev, next); prepare_lock_switch(rq, next); prepare_arch_switch(next); + trace_sched_switch(prev, next); } /** @@ -2911,7 +2893,7 @@ context_switch(struct rq *rq, struct task_struct *prev, struct mm_struct *mm, *oldmm; prepare_task_switch(rq, prev, next); - trace_sched_switch(prev, next); + mm = next->mm; oldmm = prev->active_mm; /* @@ -3989,9 +3971,6 @@ need_resched_nonpreemptible: rq->skip_clock_update = 0; if (likely(prev != next)) { - sched_info_switch(prev, next); - perf_event_task_sched_out(prev, next); - rq->nr_switches++; rq->curr = next; ++*switch_count; diff --git a/kernel/timer.c b/kernel/timer.c index 43ca993..d53ce66 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -969,10 +969,14 @@ EXPORT_SYMBOL(try_to_del_timer_sync); int del_timer_sync(struct timer_list *timer) { #ifdef CONFIG_LOCKDEP + unsigned long flags; + + raw_local_irq_save(flags); local_bh_disable(); lock_map_acquire(&timer->lockdep_map); lock_map_release(&timer->lockdep_map); - local_bh_enable(); + _local_bh_enable(); + raw_local_irq_restore(flags); #endif /* * don't use it in hardirq context, because it diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 2dec9bc..8435b43 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -353,6 +353,43 @@ static __kprobes void free_deref_fetch_param(struct deref_fetch_param *data) kfree(data); } +/* Bitfield fetch function */ +struct bitfield_fetch_param { + struct fetch_param orig; + unsigned char hi_shift; + unsigned char low_shift; +}; + +#define DEFINE_FETCH_bitfield(type) \ +static __kprobes void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs,\ + void *data, void *dest) \ +{ \ + struct bitfield_fetch_param *bprm = data; \ + type buf = 0; \ + call_fetch(&bprm->orig, regs, &buf); \ + if (buf) { \ + buf <<= bprm->hi_shift; \ + buf >>= bprm->low_shift; \ + } \ + *(type *)dest = buf; \ +} +DEFINE_BASIC_FETCH_FUNCS(bitfield) +#define fetch_bitfield_string NULL +#define fetch_bitfield_string_size NULL + +static __kprobes void +free_bitfield_fetch_param(struct bitfield_fetch_param *data) +{ + /* + * Don't check the bitfield itself, because this must be the + * last fetch function. + */ + if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) + free_deref_fetch_param(data->orig.data); + else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) + free_symbol_cache(data->orig.data); + kfree(data); +} /* Default (unsigned long) fetch type */ #define __DEFAULT_FETCH_TYPE(t) u##t #define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t) @@ -367,6 +404,7 @@ enum { FETCH_MTD_memory, FETCH_MTD_symbol, FETCH_MTD_deref, + FETCH_MTD_bitfield, FETCH_MTD_END, }; @@ -387,6 +425,7 @@ ASSIGN_FETCH_FUNC(retval, ftype), \ ASSIGN_FETCH_FUNC(memory, ftype), \ ASSIGN_FETCH_FUNC(symbol, ftype), \ ASSIGN_FETCH_FUNC(deref, ftype), \ +ASSIGN_FETCH_FUNC(bitfield, ftype), \ } \ } @@ -430,9 +469,33 @@ static const struct fetch_type *find_fetch_type(const char *type) if (!type) type = DEFAULT_FETCH_TYPE_STR; + /* Special case: bitfield */ + if (*type == 'b') { + unsigned long bs; + type = strchr(type, '/'); + if (!type) + goto fail; + type++; + if (strict_strtoul(type, 0, &bs)) + goto fail; + switch (bs) { + case 8: + return find_fetch_type("u8"); + case 16: + return find_fetch_type("u16"); + case 32: + return find_fetch_type("u32"); + case 64: + return find_fetch_type("u64"); + default: + goto fail; + } + } + for (i = 0; i < ARRAY_SIZE(fetch_type_table); i++) if (strcmp(type, fetch_type_table[i].name) == 0) return &fetch_type_table[i]; +fail: return NULL; } @@ -586,7 +649,9 @@ error: static void free_probe_arg(struct probe_arg *arg) { - if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn)) + if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn)) + free_bitfield_fetch_param(arg->fetch.data); + else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn)) free_deref_fetch_param(arg->fetch.data); else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn)) free_symbol_cache(arg->fetch.data); @@ -767,16 +832,15 @@ static int __parse_probe_arg(char *arg, const struct fetch_type *t, } break; case '+': /* deref memory */ + arg++; /* Skip '+', because strict_strtol() rejects it. */ case '-': tmp = strchr(arg, '('); if (!tmp) break; *tmp = '\0'; - ret = strict_strtol(arg + 1, 0, &offset); + ret = strict_strtol(arg, 0, &offset); if (ret) break; - if (arg[0] == '-') - offset = -offset; arg = tmp + 1; tmp = strrchr(arg, ')'); if (tmp) { @@ -807,6 +871,41 @@ static int __parse_probe_arg(char *arg, const struct fetch_type *t, return ret; } +#define BYTES_TO_BITS(nb) ((BITS_PER_LONG * (nb)) / sizeof(long)) + +/* Bitfield type needs to be parsed into a fetch function */ +static int __parse_bitfield_probe_arg(const char *bf, + const struct fetch_type *t, + struct fetch_param *f) +{ + struct bitfield_fetch_param *bprm; + unsigned long bw, bo; + char *tail; + + if (*bf != 'b') + return 0; + + bprm = kzalloc(sizeof(*bprm), GFP_KERNEL); + if (!bprm) + return -ENOMEM; + bprm->orig = *f; + f->fn = t->fetch[FETCH_MTD_bitfield]; + f->data = (void *)bprm; + + bw = simple_strtoul(bf + 1, &tail, 0); /* Use simple one */ + if (bw == 0 || *tail != '@') + return -EINVAL; + + bf = tail + 1; + bo = simple_strtoul(bf, &tail, 0); + if (tail == bf || *tail != '/') + return -EINVAL; + + bprm->hi_shift = BYTES_TO_BITS(t->size) - (bw + bo); + bprm->low_shift = bprm->hi_shift + bo; + return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0; +} + /* String length checking wrapper */ static int parse_probe_arg(char *arg, struct trace_probe *tp, struct probe_arg *parg, int is_return) @@ -836,6 +935,8 @@ static int parse_probe_arg(char *arg, struct trace_probe *tp, parg->offset = tp->size; tp->size += parg->type->size; ret = __parse_probe_arg(arg, parg->type, &parg->fetch, is_return); + if (ret >= 0 && t != NULL) + ret = __parse_bitfield_probe_arg(t, parg->type, &parg->fetch); if (ret >= 0) { parg->fetch_size.fn = get_fetch_size_function(parg->type, parg->fetch.fn); @@ -1130,7 +1231,7 @@ static int command_trace_probe(const char *buf) return ret; } -#define WRITE_BUFSIZE 128 +#define WRITE_BUFSIZE 4096 static ssize_t probes_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) diff --git a/kernel/watchdog.c b/kernel/watchdog.c index f37f974..18bb157 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -363,8 +363,14 @@ static int watchdog_nmi_enable(int cpu) goto out_save; } - printk(KERN_ERR "NMI watchdog disabled for cpu%i: unable to create perf event: %ld\n", - cpu, PTR_ERR(event)); + + /* vary the KERN level based on the returned errno */ + if (PTR_ERR(event) == -EOPNOTSUPP) + printk(KERN_INFO "NMI watchdog disabled (cpu%i): not supported (no LAPIC?)\n", cpu); + else if (PTR_ERR(event) == -ENOENT) + printk(KERN_WARNING "NMI watchdog disabled (cpu%i): hardware events not enabled\n", cpu); + else + printk(KERN_ERR "NMI watchdog disabled (cpu%i): unable to create perf event: %ld\n", cpu, PTR_ERR(event)); return PTR_ERR(event); /* success path */ |