From df561f6688fef775baa341a0f5d960becd248b11 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Sun, 23 Aug 2020 17:36:59 -0500 Subject: treewide: Use fallthrough pseudo-keyword Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva --- kernel/auditfilter.c | 2 +- kernel/bpf/cgroup.c | 2 +- kernel/bpf/cpumap.c | 2 +- kernel/bpf/syscall.c | 2 +- kernel/bpf/verifier.c | 4 ++-- kernel/capability.c | 2 +- kernel/compat.c | 6 +++--- kernel/debug/gdbstub.c | 6 +++--- kernel/debug/kdb/kdb_keyboard.c | 4 ++-- kernel/debug/kdb/kdb_support.c | 6 +++--- kernel/events/core.c | 2 +- kernel/irq/handle.c | 2 +- kernel/irq/manage.c | 4 ++-- kernel/kallsyms.c | 4 ++-- kernel/power/hibernate.c | 2 +- kernel/power/qos.c | 4 ++-- kernel/sched/core.c | 2 +- kernel/sched/topology.c | 6 +++--- kernel/signal.c | 2 +- kernel/sys.c | 2 +- kernel/time/hrtimer.c | 2 +- kernel/time/posix-timers.c | 4 ++-- kernel/time/tick-broadcast.c | 2 +- kernel/time/timer.c | 2 +- kernel/trace/blktrace.c | 2 +- kernel/trace/trace_events_filter.c | 4 ++-- 26 files changed, 41 insertions(+), 41 deletions(-) (limited to 'kernel') diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index a10e2997aa6c..333b3bcfc545 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -681,7 +681,7 @@ static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule) data->values[i] = AUDIT_UID_UNSET; break; } - /* fall through - if set */ + fallthrough; /* if set */ default: data->values[i] = f->val; } diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 83ff127ef7ae..e21de4f1754c 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -1794,7 +1794,7 @@ static bool cg_sockopt_is_valid_access(int off, int size, return prog->expected_attach_type == BPF_CGROUP_GETSOCKOPT; case offsetof(struct bpf_sockopt, optname): - /* fallthrough */ + fallthrough; case offsetof(struct bpf_sockopt, level): if (size != size_default) return false; diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index f1c46529929b..6386b7bb98f2 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -279,7 +279,7 @@ static int cpu_map_bpf_prog_run_xdp(struct bpf_cpu_map_entry *rcpu, break; default: bpf_warn_invalid_xdp_action(act); - /* fallthrough */ + fallthrough; case XDP_DROP: xdp_return_frame(xdpf); stats->drop++; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 86299a292214..1bf960aa615c 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2029,7 +2029,7 @@ bpf_prog_load_check_attach(enum bpf_prog_type prog_type, case BPF_PROG_TYPE_EXT: if (expected_attach_type) return -EINVAL; - /* fallthrough */ + fallthrough; default: return 0; } diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index ef938f17b944..47e74f09fa37 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -5236,7 +5236,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, off_reg == dst_reg ? dst : src); return -EACCES; } - /* fall-through */ + fallthrough; default: break; } @@ -10988,7 +10988,7 @@ static int check_attach_btf_id(struct bpf_verifier_env *env) default: if (!prog_extension) return -EINVAL; - /* fallthrough */ + fallthrough; case BPF_MODIFY_RETURN: case BPF_LSM_MAC: case BPF_TRACE_FENTRY: diff --git a/kernel/capability.c b/kernel/capability.c index 1444f3954d75..7c59b096c98a 100644 --- a/kernel/capability.c +++ b/kernel/capability.c @@ -93,7 +93,7 @@ static int cap_validate_magic(cap_user_header_t header, unsigned *tocopy) break; case _LINUX_CAPABILITY_VERSION_2: warn_deprecated_v2(); - /* fall through - v3 is otherwise equivalent to v2. */ + fallthrough; /* v3 is otherwise equivalent to v2 */ case _LINUX_CAPABILITY_VERSION_3: *tocopy = _LINUX_CAPABILITY_U32S_3; break; diff --git a/kernel/compat.c b/kernel/compat.c index b8d2800bb4b7..05adfd6fa8bf 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -255,11 +255,11 @@ get_compat_sigset(sigset_t *set, const compat_sigset_t __user *compat) return -EFAULT; switch (_NSIG_WORDS) { case 4: set->sig[3] = v.sig[6] | (((long)v.sig[7]) << 32 ); - /* fall through */ + fallthrough; case 3: set->sig[2] = v.sig[4] | (((long)v.sig[5]) << 32 ); - /* fall through */ + fallthrough; case 2: set->sig[1] = v.sig[2] | (((long)v.sig[3]) << 32 ); - /* fall through */ + fallthrough; case 1: set->sig[0] = v.sig[0] | (((long)v.sig[1]) << 32 ); } #else diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c index a790026e42d0..cc3c43dfec44 100644 --- a/kernel/debug/gdbstub.c +++ b/kernel/debug/gdbstub.c @@ -1046,14 +1046,14 @@ int gdb_serial_stub(struct kgdb_state *ks) return DBG_PASS_EVENT; } #endif - /* Fall through */ + fallthrough; case 'C': /* Exception passing */ tmp = gdb_cmd_exception_pass(ks); if (tmp > 0) goto default_handle; if (tmp == 0) break; - /* Fall through - on tmp < 0 */ + fallthrough; /* on tmp < 0 */ case 'c': /* Continue packet */ case 's': /* Single step packet */ if (kgdb_contthread && kgdb_contthread != current) { @@ -1062,7 +1062,7 @@ int gdb_serial_stub(struct kgdb_state *ks) break; } dbg_activate_sw_breakpoints(); - /* Fall through - to default processing */ + fallthrough; /* to default processing */ default: default_handle: error = kgdb_arch_handle_exception(ks->ex_vector, diff --git a/kernel/debug/kdb/kdb_keyboard.c b/kernel/debug/kdb/kdb_keyboard.c index 750497b0003a..f877a0a0d7cf 100644 --- a/kernel/debug/kdb/kdb_keyboard.c +++ b/kernel/debug/kdb/kdb_keyboard.c @@ -173,11 +173,11 @@ int kdb_get_kbd_char(void) case KT_LATIN: if (isprint(keychar)) break; /* printable characters */ - /* fall through */ + fallthrough; case KT_SPEC: if (keychar == K_ENTER) break; - /* fall through */ + fallthrough; default: return -1; /* ignore unprintables */ } diff --git a/kernel/debug/kdb/kdb_support.c b/kernel/debug/kdb/kdb_support.c index 004c5b6c87f8..6226502ce049 100644 --- a/kernel/debug/kdb/kdb_support.c +++ b/kernel/debug/kdb/kdb_support.c @@ -432,7 +432,7 @@ int kdb_getphysword(unsigned long *word, unsigned long addr, size_t size) *word = w8; break; } - /* fall through */ + fallthrough; default: diag = KDB_BADWIDTH; kdb_printf("kdb_getphysword: bad width %ld\n", (long) size); @@ -481,7 +481,7 @@ int kdb_getword(unsigned long *word, unsigned long addr, size_t size) *word = w8; break; } - /* fall through */ + fallthrough; default: diag = KDB_BADWIDTH; kdb_printf("kdb_getword: bad width %ld\n", (long) size); @@ -525,7 +525,7 @@ int kdb_putword(unsigned long addr, unsigned long word, size_t size) diag = kdb_putarea(addr, w8); break; } - /* fall through */ + fallthrough; default: diag = KDB_BADWIDTH; kdb_printf("kdb_putword: bad width %ld\n", (long) size); diff --git a/kernel/events/core.c b/kernel/events/core.c index 5bfe8e3c6e44..7ed5248f0445 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -10034,7 +10034,7 @@ perf_event_parse_addr_filter(struct perf_event *event, char *fstr, case IF_SRC_KERNELADDR: case IF_SRC_KERNEL: kernel = 1; - /* fall through */ + fallthrough; case IF_SRC_FILEADDR: case IF_SRC_FILE: diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c index a8e14c80b405..762a928e18f9 100644 --- a/kernel/irq/handle.c +++ b/kernel/irq/handle.c @@ -173,7 +173,7 @@ irqreturn_t __handle_irq_event_percpu(struct irq_desc *desc, unsigned int *flags __irq_wake_thread(desc, action); - /* Fall through - to add to randomness */ + fallthrough; /* to add to randomness */ case IRQ_HANDLED: *flags |= action->flags; break; diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 52ac5391dcc6..5df903fccb60 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -271,7 +271,7 @@ int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask, case IRQ_SET_MASK_OK: case IRQ_SET_MASK_OK_DONE: cpumask_copy(desc->irq_common_data.affinity, mask); - /* fall through */ + fallthrough; case IRQ_SET_MASK_OK_NOCOPY: irq_validate_effective_affinity(data); irq_set_thread_affinity(desc); @@ -868,7 +868,7 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned long flags) case IRQ_SET_MASK_OK_DONE: irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK); irqd_set(&desc->irq_data, flags); - /* fall through */ + fallthrough; case IRQ_SET_MASK_OK_NOCOPY: flags = irqd_get_trigger_type(&desc->irq_data); diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 95cb74f73292..4fb15fa96734 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -684,12 +684,12 @@ bool kallsyms_show_value(const struct cred *cred) case 0: if (kallsyms_for_perf()) return true; - /* fallthrough */ + fallthrough; case 1: if (security_capable(cred, &init_user_ns, CAP_SYSLOG, CAP_OPT_NOAUDIT) == 0) return true; - /* fallthrough */ + fallthrough; default: return false; } diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index f33769f97aca..e7aa57fb2fdc 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -659,7 +659,7 @@ static void power_down(void) break; case HIBERNATION_PLATFORM: hibernation_platform_enter(); - /* Fall through */ + fallthrough; case HIBERNATION_SHUTDOWN: if (pm_power_off) kernel_power_off(); diff --git a/kernel/power/qos.c b/kernel/power/qos.c index db0bed2cae26..ec7e1e85923e 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -119,7 +119,7 @@ int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node, * and add, then see if the aggregate has changed. */ plist_del(node, &c->list); - /* fall through */ + fallthrough; case PM_QOS_ADD_REQ: plist_node_init(node, new_value); plist_add(node, &c->list); @@ -188,7 +188,7 @@ bool pm_qos_update_flags(struct pm_qos_flags *pqf, break; case PM_QOS_UPDATE_REQ: pm_qos_flags_remove_req(pqf, req); - /* fall through */ + fallthrough; case PM_QOS_ADD_REQ: req->flags = val; INIT_LIST_HEAD(&req->node); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 8471a0f7eb32..2d95dc3f4644 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2320,7 +2320,7 @@ static int select_fallback_rq(int cpu, struct task_struct *p) state = possible; break; } - /* Fall-through */ + fallthrough; case possible: do_set_cpus_allowed(p, cpu_possible_mask); state = fail; diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 007b0a6b0152..1bd7e3af904f 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -1219,13 +1219,13 @@ static void __free_domain_allocs(struct s_data *d, enum s_alloc what, case sa_rootdomain: if (!atomic_read(&d->rd->refcount)) free_rootdomain(&d->rd->rcu); - /* Fall through */ + fallthrough; case sa_sd: free_percpu(d->sd); - /* Fall through */ + fallthrough; case sa_sd_storage: __sdt_free(cpu_map); - /* Fall through */ + fallthrough; case sa_none: break; } diff --git a/kernel/signal.c b/kernel/signal.c index 42b67d2cea37..a38b3edc6851 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -851,7 +851,7 @@ static int check_kill_permission(int sig, struct kernel_siginfo *info, */ if (!sid || sid == task_session(current)) break; - /* fall through */ + fallthrough; default: return -EPERM; } diff --git a/kernel/sys.c b/kernel/sys.c index ca11af9d815d..ab6c409b1159 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1753,7 +1753,7 @@ void getrusage(struct task_struct *p, int who, struct rusage *r) if (who == RUSAGE_CHILDREN) break; - /* fall through */ + fallthrough; case RUSAGE_SELF: thread_group_cputime_adjusted(p, &tgutime, &tgstime); diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index c4038511d5c9..95b6a708b040 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -377,7 +377,7 @@ static bool hrtimer_fixup_activate(void *addr, enum debug_obj_state state) switch (state) { case ODEBUG_STATE_ACTIVE: WARN_ON(1); - /* fall through */ + fallthrough; default: return false; } diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index 07709ac30439..bf540f5a4115 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -439,12 +439,12 @@ static struct pid *good_sigevent(sigevent_t * event) rtn = pid_task(pid, PIDTYPE_PID); if (!rtn || !same_thread_group(rtn, current)) return NULL; - /* FALLTHRU */ + fallthrough; case SIGEV_SIGNAL: case SIGEV_THREAD: if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX) return NULL; - /* FALLTHRU */ + fallthrough; case SIGEV_NONE: return pid; default: diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index e51778c312f1..36d7464c8962 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -381,7 +381,7 @@ void tick_broadcast_control(enum tick_broadcast_mode mode) switch (mode) { case TICK_BROADCAST_FORCE: tick_broadcast_forced = 1; - /* fall through */ + fallthrough; case TICK_BROADCAST_ON: cpumask_set_cpu(cpu, tick_broadcast_on); if (!cpumask_test_and_set_cpu(cpu, tick_broadcast_mask)) { diff --git a/kernel/time/timer.c b/kernel/time/timer.c index a16764b0116e..a50364df1054 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -666,7 +666,7 @@ static bool timer_fixup_activate(void *addr, enum debug_obj_state state) case ODEBUG_STATE_ACTIVE: WARN_ON(1); - /* fall through */ + fallthrough; default: return false; } diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index 7ba62d68885a..4b3a42fc3b24 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -745,7 +745,7 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) #endif case BLKTRACESTART: start = 1; - /* fall through */ + fallthrough; case BLKTRACESTOP: ret = __blk_trace_startstop(q, start); break; diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index bf44f6bbd0c3..78a678eeb140 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -499,7 +499,7 @@ predicate_parse(const char *str, int nr_parens, int nr_preds, ptr++; break; } - /* fall through */ + fallthrough; default: parse_error(pe, FILT_ERR_TOO_MANY_PREDS, next - str); @@ -1273,7 +1273,7 @@ static int parse_pred(const char *str, void *data, switch (op) { case OP_NE: pred->not = 1; - /* Fall through */ + fallthrough; case OP_GLOB: case OP_EQ: break; -- cgit v1.2.3-70-g09d2 From b474959d5afda6e341a02c85f9595d85d39189ae Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Fri, 21 Aug 2020 12:10:54 -0700 Subject: bpf: Fix a buffer out-of-bound access when filling raw_tp link_info Commit f2e10bff16a0 ("bpf: Add support for BPF_OBJ_GET_INFO_BY_FD for bpf_link") added link query for raw_tp. One of fields in link_info is to fill a user buffer with tp_name. The Scurrent checking only declares "ulen && !ubuf" as invalid. So "!ulen && ubuf" will be valid. Later on, we do "copy_to_user(ubuf, tp_name, ulen - 1)" which may overwrite user memory incorrectly. This patch fixed the problem by disallowing "!ulen && ubuf" case as well. Fixes: f2e10bff16a0 ("bpf: Add support for BPF_OBJ_GET_INFO_BY_FD for bpf_link") Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200821191054.714731-1-yhs@fb.com --- kernel/bpf/syscall.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 86299a292214..ac6c784c0576 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2634,7 +2634,7 @@ static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link, u32 ulen = info->raw_tracepoint.tp_name_len; size_t tp_len = strlen(tp_name); - if (ulen && !ubuf) + if (!ulen ^ !ubuf) return -EINVAL; info->raw_tracepoint.tp_name_len = tp_len + 1; -- cgit v1.2.3-70-g09d2 From 7787b6fc938e16aa418613c4a765c1dbb268ed9f Mon Sep 17 00:00:00 2001 From: Tobias Klauser Date: Mon, 24 Aug 2020 16:20:47 +0200 Subject: bpf, sysctl: Let bpf_stats_handler take a kernel pointer buffer Commit 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler") changed ctl_table.proc_handler to take a kernel pointer. Adjust the signature of bpf_stats_handler to match ctl_table.proc_handler which fixes the following sparse warning: kernel/sysctl.c:226:49: warning: incorrect type in argument 3 (different address spaces) kernel/sysctl.c:226:49: expected void * kernel/sysctl.c:226:49: got void [noderef] __user *buffer kernel/sysctl.c:2640:35: warning: incorrect type in initializer (incompatible argument 3 (different address spaces)) kernel/sysctl.c:2640:35: expected int ( [usertype] *proc_handler )( ... ) kernel/sysctl.c:2640:35: got int ( * )( ... ) Fixes: 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler") Signed-off-by: Tobias Klauser Signed-off-by: Alexei Starovoitov Cc: Christoph Hellwig Link: https://lore.kernel.org/bpf/20200824142047.22043-1-tklauser@distanz.ch --- kernel/sysctl.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 287862f91717..09e70ee2332e 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -204,8 +204,7 @@ static int max_extfrag_threshold = 1000; #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_SYSCTL) static int bpf_stats_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, - loff_t *ppos) + void *buffer, size_t *lenp, loff_t *ppos) { struct static_key *key = (struct static_key *)table->data; static int saved_val; -- cgit v1.2.3-70-g09d2 From fddf9055a60dfcc97bda5ef03c8fa4108ed555c5 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 20 Aug 2020 09:13:30 +0200 Subject: lockdep: Use raw_cpu_*() for per-cpu variables Sven reported that commit a21ee6055c30 ("lockdep: Change hardirq{s_enabled,_context} to per-cpu variables") caused trouble on s390 because their this_cpu_*() primitives disable preemption which then lands back tracing. On the one hand, per-cpu ops should use preempt_*able_notrace() and raw_local_irq_*(), on the other hand, we can trivialy use raw_cpu_*() ops for this. Fixes: a21ee6055c30 ("lockdep: Change hardirq{s_enabled,_context} to per-cpu variables") Reported-by: Sven Schnelle Reviewed-by: Steven Rostedt (VMware) Reviewed-by: Thomas Gleixner Acked-by: Rafael J. Wysocki Tested-by: Marco Elver Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20200821085348.192346882@infradead.org --- include/linux/irqflags.h | 6 +++--- include/linux/lockdep.h | 18 +++++++++++++----- kernel/locking/lockdep.c | 4 ++-- 3 files changed, 18 insertions(+), 10 deletions(-) (limited to 'kernel') diff --git a/include/linux/irqflags.h b/include/linux/irqflags.h index bd5c55755447..d7e50a215ea9 100644 --- a/include/linux/irqflags.h +++ b/include/linux/irqflags.h @@ -53,13 +53,13 @@ DECLARE_PER_CPU(int, hardirq_context); extern void trace_hardirqs_off_finish(void); extern void trace_hardirqs_on(void); extern void trace_hardirqs_off(void); -# define lockdep_hardirq_context() (this_cpu_read(hardirq_context)) +# define lockdep_hardirq_context() (raw_cpu_read(hardirq_context)) # define lockdep_softirq_context(p) ((p)->softirq_context) # define lockdep_hardirqs_enabled() (this_cpu_read(hardirqs_enabled)) # define lockdep_softirqs_enabled(p) ((p)->softirqs_enabled) # define lockdep_hardirq_enter() \ do { \ - if (this_cpu_inc_return(hardirq_context) == 1) \ + if (__this_cpu_inc_return(hardirq_context) == 1)\ current->hardirq_threaded = 0; \ } while (0) # define lockdep_hardirq_threaded() \ @@ -68,7 +68,7 @@ do { \ } while (0) # define lockdep_hardirq_exit() \ do { \ - this_cpu_dec(hardirq_context); \ + __this_cpu_dec(hardirq_context); \ } while (0) # define lockdep_softirq_enter() \ do { \ diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index 62a382d1845b..6a584b3e5c74 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -535,19 +535,27 @@ do { \ DECLARE_PER_CPU(int, hardirqs_enabled); DECLARE_PER_CPU(int, hardirq_context); +/* + * The below lockdep_assert_*() macros use raw_cpu_read() to access the above + * per-cpu variables. This is required because this_cpu_read() will potentially + * call into preempt/irq-disable and that obviously isn't right. This is also + * correct because when IRQs are enabled, it doesn't matter if we accidentally + * read the value from our previous CPU. + */ + #define lockdep_assert_irqs_enabled() \ do { \ - WARN_ON_ONCE(debug_locks && !this_cpu_read(hardirqs_enabled)); \ + WARN_ON_ONCE(debug_locks && !raw_cpu_read(hardirqs_enabled)); \ } while (0) #define lockdep_assert_irqs_disabled() \ do { \ - WARN_ON_ONCE(debug_locks && this_cpu_read(hardirqs_enabled)); \ + WARN_ON_ONCE(debug_locks && raw_cpu_read(hardirqs_enabled)); \ } while (0) #define lockdep_assert_in_irq() \ do { \ - WARN_ON_ONCE(debug_locks && !this_cpu_read(hardirq_context)); \ + WARN_ON_ONCE(debug_locks && !raw_cpu_read(hardirq_context)); \ } while (0) #define lockdep_assert_preemption_enabled() \ @@ -555,7 +563,7 @@ do { \ WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT) && \ debug_locks && \ (preempt_count() != 0 || \ - !this_cpu_read(hardirqs_enabled))); \ + !raw_cpu_read(hardirqs_enabled))); \ } while (0) #define lockdep_assert_preemption_disabled() \ @@ -563,7 +571,7 @@ do { \ WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT) && \ debug_locks && \ (preempt_count() == 0 && \ - this_cpu_read(hardirqs_enabled))); \ + raw_cpu_read(hardirqs_enabled))); \ } while (0) #else diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 2fad21d345b0..c872e95e6e4d 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -3756,7 +3756,7 @@ void noinstr lockdep_hardirqs_on(unsigned long ip) skip_checks: /* we'll do an OFF -> ON transition: */ - this_cpu_write(hardirqs_enabled, 1); + __this_cpu_write(hardirqs_enabled, 1); trace->hardirq_enable_ip = ip; trace->hardirq_enable_event = ++trace->irq_events; debug_atomic_inc(hardirqs_on_events); @@ -3795,7 +3795,7 @@ void noinstr lockdep_hardirqs_off(unsigned long ip) /* * We have done an ON -> OFF transition: */ - this_cpu_write(hardirqs_enabled, 0); + __this_cpu_write(hardirqs_enabled, 0); trace->hardirq_disable_ip = ip; trace->hardirq_disable_event = ++trace->irq_events; debug_atomic_inc(hardirqs_off_events); -- cgit v1.2.3-70-g09d2 From 1098582a0f6c4e8fd28da0a6305f9233d02c9c1d Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Fri, 7 Aug 2020 20:50:19 +0200 Subject: sched,idle,rcu: Push rcu_idle deeper into the idle path Lots of things take locks, due to a wee bug, rcu_lockdep didn't notice that the locking tracepoints were using RCU. Push rcu_idle_{enter,exit}() as deep as possible into the idle paths, this also resolves a lot of _rcuidle()/RCU_NONIDLE() usage. Specifically, sched_clock_idle_wakeup_event() will use ktime which will use seqlocks which will tickle lockdep, and stop_critical_timings() uses lock. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Steven Rostedt (VMware) Reviewed-by: Thomas Gleixner Acked-by: Rafael J. Wysocki Tested-by: Marco Elver Link: https://lkml.kernel.org/r/20200821085348.310943801@infradead.org --- drivers/cpuidle/cpuidle.c | 12 ++++++++---- kernel/sched/idle.c | 22 ++++++++-------------- 2 files changed, 16 insertions(+), 18 deletions(-) (limited to 'kernel') diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 2fe4f3cdf54d..9bcda4153d3b 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -145,13 +145,14 @@ static void enter_s2idle_proper(struct cpuidle_driver *drv, * executing it contains RCU usage regarded as invalid in the idle * context, so tell RCU about that. */ - RCU_NONIDLE(tick_freeze()); + tick_freeze(); /* * The state used here cannot be a "coupled" one, because the "coupled" * cpuidle mechanism enables interrupts and doing that with timekeeping * suspended is generally unsafe. */ stop_critical_timings(); + rcu_idle_enter(); drv->states[index].enter_s2idle(dev, drv, index); if (WARN_ON_ONCE(!irqs_disabled())) local_irq_disable(); @@ -160,7 +161,8 @@ static void enter_s2idle_proper(struct cpuidle_driver *drv, * first CPU executing it calls functions containing RCU read-side * critical sections, so tell RCU about that. */ - RCU_NONIDLE(tick_unfreeze()); + rcu_idle_exit(); + tick_unfreeze(); start_critical_timings(); time_end = ns_to_ktime(local_clock()); @@ -229,16 +231,18 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv, /* Take note of the planned idle state. */ sched_idle_set_state(target_state); - trace_cpu_idle_rcuidle(index, dev->cpu); + trace_cpu_idle(index, dev->cpu); time_start = ns_to_ktime(local_clock()); stop_critical_timings(); + rcu_idle_enter(); entered_state = target_state->enter(dev, drv, index); + rcu_idle_exit(); start_critical_timings(); sched_clock_idle_wakeup_event(); time_end = ns_to_ktime(local_clock()); - trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu); + trace_cpu_idle(PWR_EVENT_EXIT, dev->cpu); /* The cpu is no longer idle or about to enter idle. */ sched_idle_set_state(NULL); diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index 6bf34986f45c..ea3a0989dc4c 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -54,17 +54,18 @@ __setup("hlt", cpu_idle_nopoll_setup); static noinline int __cpuidle cpu_idle_poll(void) { + trace_cpu_idle(0, smp_processor_id()); + stop_critical_timings(); rcu_idle_enter(); - trace_cpu_idle_rcuidle(0, smp_processor_id()); local_irq_enable(); - stop_critical_timings(); while (!tif_need_resched() && - (cpu_idle_force_poll || tick_check_broadcast_expired())) + (cpu_idle_force_poll || tick_check_broadcast_expired())) cpu_relax(); - start_critical_timings(); - trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id()); + rcu_idle_exit(); + start_critical_timings(); + trace_cpu_idle(PWR_EVENT_EXIT, smp_processor_id()); return 1; } @@ -91,7 +92,9 @@ void __cpuidle default_idle_call(void) local_irq_enable(); } else { stop_critical_timings(); + rcu_idle_enter(); arch_cpu_idle(); + rcu_idle_exit(); start_critical_timings(); } } @@ -158,7 +161,6 @@ static void cpuidle_idle_call(void) if (cpuidle_not_available(drv, dev)) { tick_nohz_idle_stop_tick(); - rcu_idle_enter(); default_idle_call(); goto exit_idle; @@ -178,21 +180,17 @@ static void cpuidle_idle_call(void) u64 max_latency_ns; if (idle_should_enter_s2idle()) { - rcu_idle_enter(); entered_state = call_cpuidle_s2idle(drv, dev); if (entered_state > 0) goto exit_idle; - rcu_idle_exit(); - max_latency_ns = U64_MAX; } else { max_latency_ns = dev->forced_idle_latency_limit_ns; } tick_nohz_idle_stop_tick(); - rcu_idle_enter(); next_state = cpuidle_find_deepest_state(drv, dev, max_latency_ns); call_cpuidle(drv, dev, next_state); @@ -209,8 +207,6 @@ static void cpuidle_idle_call(void) else tick_nohz_idle_retain_tick(); - rcu_idle_enter(); - entered_state = call_cpuidle(drv, dev, next_state); /* * Give the governor an opportunity to reflect on the outcome @@ -226,8 +222,6 @@ exit_idle: */ if (WARN_ON_ONCE(irqs_disabled())) local_irq_enable(); - - rcu_idle_exit(); } /* -- cgit v1.2.3-70-g09d2 From 9864f5b5943ab0f1f835f21dc3f9f068d06f5b52 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 12 Aug 2020 12:27:10 +0200 Subject: cpuidle: Move trace_cpu_idle() into generic code Remove trace_cpu_idle() from the arch_cpu_idle() implementations and put it in the generic code, right before disabling RCU. Gets rid of more trace_*_rcuidle() users. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Steven Rostedt (VMware) Reviewed-by: Thomas Gleixner Acked-by: Rafael J. Wysocki Tested-by: Marco Elver Link: https://lkml.kernel.org/r/20200821085348.428433395@infradead.org --- arch/arm/mach-omap2/pm34xx.c | 4 ---- arch/arm64/kernel/process.c | 2 -- arch/s390/kernel/idle.c | 3 +-- arch/x86/kernel/process.c | 4 ---- kernel/sched/idle.c | 3 +++ 5 files changed, 4 insertions(+), 12 deletions(-) (limited to 'kernel') diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c index 6df395fff971..f5dfddf492e2 100644 --- a/arch/arm/mach-omap2/pm34xx.c +++ b/arch/arm/mach-omap2/pm34xx.c @@ -298,11 +298,7 @@ static void omap3_pm_idle(void) if (omap_irq_pending()) return; - trace_cpu_idle_rcuidle(1, smp_processor_id()); - omap_sram_idle(); - - trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id()); } #ifdef CONFIG_SUSPEND diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index b63ce4c54cfe..f1804496b935 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -123,10 +123,8 @@ void arch_cpu_idle(void) * This should do all the clock switching and wait for interrupt * tricks */ - trace_cpu_idle_rcuidle(1, smp_processor_id()); cpu_do_idle(); local_irq_enable(); - trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id()); } #ifdef CONFIG_HOTPLUG_CPU diff --git a/arch/s390/kernel/idle.c b/arch/s390/kernel/idle.c index 88bb42ca5008..c73f50649e7e 100644 --- a/arch/s390/kernel/idle.c +++ b/arch/s390/kernel/idle.c @@ -33,14 +33,13 @@ void enabled_wait(void) PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK; clear_cpu_flag(CIF_NOHZ_DELAY); - trace_cpu_idle_rcuidle(1, smp_processor_id()); local_irq_save(flags); /* Call the assembler magic in entry.S */ psw_idle(idle, psw_mask); local_irq_restore(flags); - trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id()); /* Account time spent with enabled wait psw loaded as idle time. */ + /* XXX seqcount has tracepoints that require RCU */ write_seqcount_begin(&idle->seqcount); idle_time = idle->clock_idle_exit - idle->clock_idle_enter; idle->clock_idle_enter = idle->clock_idle_exit = 0ULL; diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 994d8393f2f7..13ce616cc7af 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -684,9 +684,7 @@ void arch_cpu_idle(void) */ void __cpuidle default_idle(void) { - trace_cpu_idle_rcuidle(1, smp_processor_id()); safe_halt(); - trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id()); } #if defined(CONFIG_APM_MODULE) || defined(CONFIG_HALTPOLL_CPUIDLE_MODULE) EXPORT_SYMBOL(default_idle); @@ -792,7 +790,6 @@ static int prefer_mwait_c1_over_halt(const struct cpuinfo_x86 *c) static __cpuidle void mwait_idle(void) { if (!current_set_polling_and_test()) { - trace_cpu_idle_rcuidle(1, smp_processor_id()); if (this_cpu_has(X86_BUG_CLFLUSH_MONITOR)) { mb(); /* quirk */ clflush((void *)¤t_thread_info()->flags); @@ -804,7 +801,6 @@ static __cpuidle void mwait_idle(void) __sti_mwait(0, 0); else local_irq_enable(); - trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id()); } else { local_irq_enable(); } diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index ea3a0989dc4c..f324dc36fc43 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -91,11 +91,14 @@ void __cpuidle default_idle_call(void) if (current_clr_polling_and_test()) { local_irq_enable(); } else { + + trace_cpu_idle(1, smp_processor_id()); stop_critical_timings(); rcu_idle_enter(); arch_cpu_idle(); rcu_idle_exit(); start_critical_timings(); + trace_cpu_idle(PWR_EVENT_EXIT, smp_processor_id()); } } -- cgit v1.2.3-70-g09d2 From eb1f00237aca2e368b93db79303f8433d1976d10 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Fri, 7 Aug 2020 20:53:16 +0200 Subject: lockdep,trace: Expose tracepoints The lockdep tracepoints are under the lockdep recursion counter, this has a bunch of nasty side effects: - TRACE_IRQFLAGS doesn't work across the entire tracepoint - RCU-lockdep doesn't see the tracepoints either, hiding numerous "suspicious RCU usage" warnings. Pull the trace_lock_*() tracepoints completely out from under the lockdep recursion handling and completely rely on the trace level recusion handling -- also, tracing *SHOULD* not be taking locks in any case. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Steven Rostedt (VMware) Reviewed-by: Thomas Gleixner Acked-by: Rafael J. Wysocki Tested-by: Marco Elver Link: https://lkml.kernel.org/r/20200821085348.782688941@infradead.org --- kernel/locking/lockdep.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) (limited to 'kernel') diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index c872e95e6e4d..54b74fabf40c 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -4977,6 +4977,8 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass, { unsigned long flags; + trace_lock_acquire(lock, subclass, trylock, read, check, nest_lock, ip); + if (unlikely(current->lockdep_recursion)) { /* XXX allow trylock from NMI ?!? */ if (lockdep_nmi() && !trylock) { @@ -5001,7 +5003,6 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass, check_flags(flags); current->lockdep_recursion++; - trace_lock_acquire(lock, subclass, trylock, read, check, nest_lock, ip); __lock_acquire(lock, subclass, trylock, read, check, irqs_disabled_flags(flags), nest_lock, ip, 0, 0); lockdep_recursion_finish(); @@ -5013,13 +5014,15 @@ void lock_release(struct lockdep_map *lock, unsigned long ip) { unsigned long flags; + trace_lock_release(lock, ip); + if (unlikely(current->lockdep_recursion)) return; raw_local_irq_save(flags); check_flags(flags); + current->lockdep_recursion++; - trace_lock_release(lock, ip); if (__lock_release(lock, ip)) check_chain_key(current); lockdep_recursion_finish(); @@ -5205,8 +5208,6 @@ __lock_acquired(struct lockdep_map *lock, unsigned long ip) hlock->holdtime_stamp = now; } - trace_lock_acquired(lock, ip); - stats = get_lock_stats(hlock_class(hlock)); if (waittime) { if (hlock->read) @@ -5225,6 +5226,8 @@ void lock_contended(struct lockdep_map *lock, unsigned long ip) { unsigned long flags; + trace_lock_acquired(lock, ip); + if (unlikely(!lock_stat || !debug_locks)) return; @@ -5234,7 +5237,6 @@ void lock_contended(struct lockdep_map *lock, unsigned long ip) raw_local_irq_save(flags); check_flags(flags); current->lockdep_recursion++; - trace_lock_contended(lock, ip); __lock_contended(lock, ip); lockdep_recursion_finish(); raw_local_irq_restore(flags); @@ -5245,6 +5247,8 @@ void lock_acquired(struct lockdep_map *lock, unsigned long ip) { unsigned long flags; + trace_lock_contended(lock, ip); + if (unlikely(!lock_stat || !debug_locks)) return; -- cgit v1.2.3-70-g09d2 From 892fc9f6835ecf075efac20789b012c5c9997fcc Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Wed, 26 Aug 2020 14:33:30 +0300 Subject: dma-pool: Fix an uninitialized variable bug in atomic_pool_expand() The "page" pointer can be used with out being initialized. Fixes: d7e673ec2c8e ("dma-pool: Only allocate from CMA when in same memory zone") Signed-off-by: Dan Carpenter Signed-off-by: Christoph Hellwig --- kernel/dma/pool.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c index 06582b488e31..1281c0f0442b 100644 --- a/kernel/dma/pool.c +++ b/kernel/dma/pool.c @@ -84,7 +84,7 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, gfp_t gfp) { unsigned int order; - struct page *page; + struct page *page = NULL; void *addr; int ret = -ENOMEM; -- cgit v1.2.3-70-g09d2 From 784a0830377d0761834e385975bc46861fea9fa0 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sun, 30 Aug 2020 19:07:53 +0200 Subject: genirq/matrix: Deal with the sillyness of for_each_cpu() on UP Most of the CPU mask operations behave the same way, but for_each_cpu() and it's variants ignore the cpumask argument and claim that CPU0 is always in the mask. This is historical, inconsistent and annoying behaviour. The matrix allocator uses for_each_cpu() and can be called on UP with an empty cpumask. The calling code does not expect that this succeeds but until commit e027fffff799 ("x86/irq: Unbreak interrupt affinity setting") this went unnoticed. That commit added a WARN_ON() to catch cases which move an interrupt from one vector to another on the same CPU. The warning triggers on UP. Add a check for the cpumask being empty to prevent this. Fixes: 2f75d9e1c905 ("genirq: Implement bitmap matrix allocator") Reported-by: kernel test robot Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org --- kernel/irq/matrix.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'kernel') diff --git a/kernel/irq/matrix.c b/kernel/irq/matrix.c index 30cc217b8631..651a4ad6d711 100644 --- a/kernel/irq/matrix.c +++ b/kernel/irq/matrix.c @@ -380,6 +380,13 @@ int irq_matrix_alloc(struct irq_matrix *m, const struct cpumask *msk, unsigned int cpu, bit; struct cpumap *cm; + /* + * Not required in theory, but matrix_find_best_cpu() uses + * for_each_cpu() which ignores the cpumask on UP . + */ + if (cpumask_empty(msk)) + return -EINVAL; + cpu = matrix_find_best_cpu(m, msk); if (cpu == UINT_MAX) return -ENOSPC; -- cgit v1.2.3-70-g09d2 From cfc905f158eaa099d6258031614d11869e7ef71c Mon Sep 17 00:00:00 2001 From: Leon Romanovsky Date: Fri, 4 Sep 2020 18:58:08 +0300 Subject: gcov: Disable gcov build with GCC 10 GCOV built with GCC 10 doesn't initialize n_function variable. This produces different kernel panics as was seen by Colin in Ubuntu and me in FC 32. As a workaround, let's disable GCOV build for broken GCC 10 version. Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1891288 Link: https://lore.kernel.org/lkml/20200827133932.3338519-1-leon@kernel.org Link: https://lore.kernel.org/lkml/CAHk-=whbijeSdSvx-Xcr0DPMj0BiwhJ+uiNnDSVZcr_h_kg7UA@mail.gmail.com/ Cc: Colin Ian King Signed-off-by: Leon Romanovsky Signed-off-by: Linus Torvalds --- kernel/gcov/Kconfig | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel') diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig index 3110c77230c7..bb4b680e8455 100644 --- a/kernel/gcov/Kconfig +++ b/kernel/gcov/Kconfig @@ -4,6 +4,7 @@ menu "GCOV-based kernel profiling" config GCOV_KERNEL bool "Enable gcov-based kernel profiling" depends on DEBUG_FS + depends on !CC_IS_GCC || GCC_VERSION < 100000 select CONSTRUCTORS if !UML default n help -- cgit v1.2.3-70-g09d2