linux-stable/kernel
Boqun Feng c6090fe788 locking/lockdep: Avoid recursion in lockdep_count_{for,back}ward_deps()
[ Upstream commit 25016bd7f4 ]

Qian Cai reported a bug when PROVE_RCU_LIST=y, and read on /proc/lockdep
triggered a warning:

  [ ] DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled)
  ...
  [ ] Call Trace:
  [ ]  lock_is_held_type+0x5d/0x150
  [ ]  ? rcu_lockdep_current_cpu_online+0x64/0x80
  [ ]  rcu_read_lock_any_held+0xac/0x100
  [ ]  ? rcu_read_lock_held+0xc0/0xc0
  [ ]  ? __slab_free+0x421/0x540
  [ ]  ? kasan_kmalloc+0x9/0x10
  [ ]  ? __kmalloc_node+0x1d7/0x320
  [ ]  ? kvmalloc_node+0x6f/0x80
  [ ]  __bfs+0x28a/0x3c0
  [ ]  ? class_equal+0x30/0x30
  [ ]  lockdep_count_forward_deps+0x11a/0x1a0

The warning got triggered because lockdep_count_forward_deps() call
__bfs() without current->lockdep_recursion being set, as a result
a lockdep internal function (__bfs()) is checked by lockdep, which is
unexpected, and the inconsistency between the irq-off state and the
state traced by lockdep caused the warning.

Apart from this warning, lockdep internal functions like __bfs() should
always be protected by current->lockdep_recursion to avoid potential
deadlocks and data inconsistency, therefore add the
current->lockdep_recursion on-and-off section to protect __bfs() in both
lockdep_count_forward_deps() and lockdep_count_backward_deps()

Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200312151258.128036-1-boqun.feng@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-17 10:48:42 +02:00
..
bpf bpf: Explicitly memset some bpf info structures declared on the stack 2020-04-02 15:28:23 +02:00
cgroup cgroup1: don't call release_agent when it is "" 2020-04-02 15:28:14 +02:00
configs kconfig: tinyconfig: remove stale stack protector fixups 2018-06-15 07:15:28 +09:00
debug kdb: do a sanity check on the cpu in kdb_per_cpu() 2020-01-27 14:50:48 +01:00
dma dma-debug: add a schedule point in debug_dma_dump_mappings() 2020-01-04 19:12:43 +01:00
events perf/core: Fix mlock accounting in perf_mmap() 2020-02-11 04:34:19 -08:00
gcov gcov: remove CONFIG_GCOV_FORMAT_AUTODETECT 2018-06-08 18:56:02 +09:00
irq genirq/irqdomain: Check pointer in irq_domain_alloc_irqs_hierarchy() 2020-04-17 10:48:41 +02:00
livepatch livepatch: Nullify obj->mod in klp_module_coming()'s error path 2019-10-07 18:57:10 +02:00
locking locking/lockdep: Avoid recursion in lockdep_count_{for,back}ward_deps() 2020-04-17 10:48:42 +02:00
power PM / hibernate: memory_bm_find_bit(): Tighten node optimisation 2020-01-09 10:18:58 +01:00
printk printk: fix exclusive_console replaying 2020-02-11 04:33:51 -08:00
rcu rcu: Avoid data-race in rcu_gp_fqs_check_wake() 2020-02-11 04:33:55 -08:00
sched sched: Avoid scale real weight down to zero 2020-04-17 10:48:40 +02:00
time clocksource: Prevent double add_timer_on() for watchdog_timer 2020-02-11 04:34:18 -08:00
trace tracing: Disable trace_printk() on post poned tests 2020-03-05 16:42:18 +01:00
.gitignore
acct.c acct_on(): don't mess with freeze protection 2019-05-31 06:46:05 -07:00
async.c
audit.c audit: always check the netlink payload length in audit_receive_msg() 2020-03-05 16:42:23 +01:00
audit.h audit: track the owner of the command mutex ourselves 2018-02-23 11:22:22 -05:00
audit_fsnotify.c fsnotify: add fsnotify_add_inode_mark() wrappers 2018-05-18 14:58:22 +02:00
audit_tree.c audit: Embed key into chunk 2019-12-13 08:51:11 +01:00
audit_watch.c audit_get_nd(): don't unlock parent too early 2019-12-13 08:51:02 +01:00
auditfilter.c audit: fix error handling in audit_data_to_entry() 2020-03-05 16:42:17 +01:00
auditsc.c audit: print empty EXECVE args 2019-12-01 09:17:17 +01:00
backtracetest.c
bounds.c kbuild: fix kernel/bounds.c 'W=1' warning 2018-11-13 11:08:47 -08:00
capability.c LSM: generalize flag passing to security_capable 2020-01-23 08:21:29 +01:00
compat.c time: Enable get/put_compat_itimerspec64 always 2018-06-24 14:39:47 +02:00
configs.c
context_tracking.c
cpu.c cpu/hotplug, stop_machine: Fix stop_machine vs hotplug order 2020-02-24 08:34:35 +01:00
cpu_pm.c
crash_core.c kernel/crash_core.c: print timestamp using time64_t 2018-08-22 10:52:47 -07:00
crash_dump.c
cred.c memcg: account security cred as well to kmemcg 2020-01-09 10:19:00 +01:00
delayacct.c delayacct: Use raw_spinlocks 2018-04-27 14:34:51 +02:00
dma.c proc: introduce proc_create_single{,_data} 2018-05-16 07:23:35 +02:00
elfcore.c kernel/elfcore.c: include proper prototypes 2019-10-11 18:21:23 +02:00
exec_domain.c proc: introduce proc_create_single{,_data} 2018-05-16 07:23:35 +02:00
exit.c exit: panic before exit_mm() on global init exit 2020-01-09 10:19:02 +01:00
extable.c extable: Make init_kernel_text() global 2018-02-21 16:54:06 +01:00
fail_function.c bpf/error-inject/kprobes: Clear current_kprobe and enable preempt in kprobe 2018-06-21 12:33:19 +02:00
fork.c fork,memcg: alloc_thread_stack_node needs to set tsk->stack 2020-01-27 14:50:58 +01:00
freezer.c PM / reboot: Eliminate race between reboot and suspend 2018-08-06 12:35:20 +02:00
futex.c futex: Unbreak futex hashing 2020-03-25 08:06:14 +01:00
groups.c
hung_task.c kernel: hung_task.c: disable on suspend 2019-04-20 09:16:02 +02:00
iomem.c memremap: split devm_memremap_pages() and memremap() infrastructure 2018-05-15 23:08:33 -07:00
irq_work.c irq_work: Do not raise an IPI when queueing work on the local CPU 2019-05-31 06:46:19 -07:00
jump_label.c jump_label: move 'asm goto' support test to Kconfig 2019-06-04 08:02:34 +02:00
kallsyms.c kallsyms: Don't let kallsyms_lookup_size_offset() fail on retrieving the first symbol 2019-09-21 07:17:02 +02:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt kconfig: include kernel/Kconfig.preempt from init/Kconfig 2018-08-02 08:06:54 +09:00
kcov.c kernel/kcov.c: mark write_comp_data() as notrace 2019-02-12 19:47:20 +01:00
kexec.c kexec: add call to LSM hook in original kexec_load syscall 2018-07-16 12:31:57 -07:00
kexec_core.c kexec: Allocate decrypted control pages for kdump if SME is enabled 2019-11-24 08:20:29 +01:00
kexec_file.c treewide: Use array_size() in vzalloc() 2018-06-12 16:19:22 -07:00
kexec_internal.h
kmod.c
kprobes.c kprobes: Fix optimize_kprobe()/unoptimize_kprobe() cancellation logic 2020-03-11 14:14:47 +01:00
ksysfs.c
kthread.c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-08-13 11:25:07 -07:00
latencytop.c
Makefile y2038: futex: Move compat implementation into futex.c 2019-12-01 09:17:38 +01:00
memremap.c mm/memory_hotplug: shrink zones when offlining memory 2020-01-29 16:43:27 +01:00
module-internal.h modsign: log module name in the event of an error 2018-07-02 11:36:17 +02:00
module.c module: avoid setting info->name early in case we can fall back to info->mod->name 2020-02-24 08:34:49 +01:00
module_signing.c modsign: log module name in the event of an error 2018-07-02 11:36:17 +02:00
notifier.c x86/mm: split vmalloc_sync_all() 2020-03-25 08:06:13 +01:00
nsproxy.c
padata.c padata: always acquire cpu_hotplug_lock before pinst->lock 2020-04-13 10:45:05 +02:00
panic.c kernel/panic.c: do not append newline to the stack protector panic string 2019-12-01 09:17:10 +01:00
params.c kernel/params.c: downgrade warning for unsafe parameters 2018-04-11 10:28:37 -07:00
pid.c Fix failure path in alloc_pid() 2019-01-13 09:51:06 +01:00
pid_namespace.c signal/pid_namespace: Fix reboot_pid_ns to use send_sig not force_sig 2019-07-26 09:14:01 +02:00
profile.c
ptrace.c ptrace: reintroduce usage of subjective credentials in ptrace_has_cap() 2020-01-23 08:21:29 +01:00
range.c
reboot.c PM / reboot: Eliminate race between reboot and suspend 2018-08-06 12:35:20 +02:00
relay.c relay: check return of create_buf_file() properly 2019-03-13 14:02:35 -07:00
resource.c resource: fix locking in find_next_iomem_res() 2019-09-16 08:22:20 +02:00
rseq.c rseq: uapi: Declare rseq_cs field as union, update includes 2018-07-10 22:18:52 +02:00
seccomp.c LSM: generalize flag passing to security_capable 2020-01-23 08:21:29 +01:00
signal.c signal: avoid double atomic counter increments for user accounting 2020-03-20 11:55:53 +01:00
smp.c cpu/hotplug: Fix "SMT disabled by BIOS" detection for KVM 2019-02-12 19:47:25 +01:00
smpboot.c smpboot: Remove cpumask from the API 2018-07-03 09:20:44 +02:00
smpboot.h
softirq.c nohz: Fix missing tick reprogram when interrupting an inline softirq 2018-08-03 15:52:10 +02:00
stacktrace.c
stop_machine.c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-08-13 11:25:07 -07:00
sys.c kernel/sys.c: prctl: fix false positive in validate_prctl_map() 2019-06-15 11:54:01 +02:00
sys_ni.c Merge branch 'core-rseq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-10 10:17:09 -07:00
sysctl.c kernel: sysctl: make drop_caches write-only 2020-01-04 19:13:17 +01:00
sysctl_binary.c staging: irda: remove remaining remants of irda code removal 2018-04-16 11:26:49 +02:00
task_work.c
taskstats.c taskstats: fix data-race 2020-01-09 10:18:59 +01:00
test_kprobes.c kprobes: Remove jprobe API implementation 2018-06-21 12:33:05 +02:00
torture.c torture: Keep old-school dmesg format 2018-06-25 11:30:10 -07:00
tracepoint.c tracepoint: Fix tracepoint array element size mismatch 2018-10-17 15:35:29 -04:00
tsacct.c
ucount.c headers: untangle kmemleak.h from mm.h 2018-04-05 21:36:27 -07:00
uid16.c fs: add do_fchownat(), ksys_fchown() helpers and ksys_{,l}chown() wrappers 2018-04-02 20:15:59 +02:00
uid16.h kernel: provide ksys_*() wrappers for syscalls called by kernel/uid16.c 2018-04-02 20:15:30 +02:00
umh.c umh: fix race condition 2018-06-07 16:56:28 -04:00
up.c
user-return-notifier.c
user.c userns: use irqsave variant of refcount_dec_and_lock() 2018-08-22 10:52:47 -07:00
user_namespace.c userns: also map extents in the reverse map to kernel IDs 2018-11-13 11:09:00 -08:00
utsname.c uts: create "struct uts_namespace" from kmem_cache 2018-04-11 10:28:35 -07:00
utsname_sysctl.c sys: don't hold uts_sem while accessing userspace memory 2018-08-11 02:05:53 -05:00
watchdog.c watchdog/softlockup: Enforce that timestamp is valid on boot 2020-02-24 08:34:49 +01:00
watchdog_hld.c watchdog: Mark watchdog touch functions as notrace 2018-08-30 12:56:40 +02:00
workqueue.c workqueue: don't use wq_select_unbound_cpu() for bound works 2020-03-18 07:14:20 +01:00
workqueue_internal.h workqueue: Set worker->desc to workqueue name by default 2018-05-18 08:47:13 -07:00