android_kernel_sony_sdm845/kernel
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Daniel Jordan 4b414f5332 padata: use smp_mb in padata_reorder to avoid orphaned padata jobs
commit cf144f81a99d1a3928f90b0936accfd3f45c9a0a upstream.

Testing padata with the tcrypt module on a 5.2 kernel...

    # modprobe tcrypt alg="pcrypt(rfc4106(gcm(aes)))" type=3
    # modprobe tcrypt mode=211 sec=1

...produces this splat:

    INFO: task modprobe:10075 blocked for more than 120 seconds.
          Not tainted 5.2.0-base+ #16
    modprobe        D    0 10075  10064 0x80004080
    Call Trace:
     ? __schedule+0x4dd/0x610
     ? ring_buffer_unlock_commit+0x23/0x100
     schedule+0x6c/0x90
     schedule_timeout+0x3b/0x320
     ? trace_buffer_unlock_commit_regs+0x4f/0x1f0
     wait_for_common+0x160/0x1a0
     ? wake_up_q+0x80/0x80
     { crypto_wait_req }             # entries in braces added by hand
     { do_one_aead_op }
     { test_aead_jiffies }
     test_aead_speed.constprop.17+0x681/0xf30 [tcrypt]
     do_test+0x4053/0x6a2b [tcrypt]
     ? 0xffffffffa00f4000
     tcrypt_mod_init+0x50/0x1000 [tcrypt]
     ...

The second modprobe command never finishes because in padata_reorder,
CPU0's load of reorder_objects is executed before the unlocking store in
spin_unlock_bh(pd->lock), causing CPU0 to miss CPU1's increment:

CPU0                                 CPU1

padata_reorder                       padata_do_serial
  LOAD reorder_objects  // 0
                                       INC reorder_objects  // 1
                                       padata_reorder
                                         TRYLOCK pd->lock   // failed
  UNLOCK pd->lock

CPU0 deletes the timer before returning from padata_reorder and since no
other job is submitted to padata, modprobe waits indefinitely.

Add a pair of full barriers to guarantee proper ordering:

CPU0                                 CPU1

padata_reorder                       padata_do_serial
  UNLOCK pd->lock
  smp_mb()
  LOAD reorder_objects
                                       INC reorder_objects
                                       smp_mb__after_atomic()
                                       padata_reorder
                                         TRYLOCK pd->lock

smp_mb__after_atomic is needed so the read part of the trylock operation
comes after the INC, as Andrea points out.   Thanks also to Andrea for
help with writing a litmus test.

Fixes: 16295bec63 ("padata: Generic parallelization/serialization interface")
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: <stable@vger.kernel.org>
Cc: Andrea Parri <andrea.parri@amarulasolutions.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-04 09:33:28 +02:00
..
bpf bpf: silence warning messages in core 2019-08-04 09:33:19 +02:00
configs config: android: enable CONFIG_SECCOMP 2016-10-11 15:06:32 -07:00
debug kdb: use memmove instead of overlapping memcpy 2018-12-08 13:05:05 +01:00
events perf/core: Fix perf_sample_regs_user() mm check 2019-07-21 09:06:05 +02:00
gcov gcov: support GCC 7.1 2017-09-02 07:07:53 +02:00
irq genirq: Prevent use-after-free and work list corruption 2019-05-10 17:52:10 +02:00
livepatch livepatch/module: make TAINT_LIVEPATCH module-specific 2016-08-26 14:42:08 +02:00
locking locking/lockdep: Fix merging of hlocks with non-zero references 2019-08-04 09:33:17 +02:00
power x86/power: Fix 'nosmt' vs hibernation triple fault during resume 2019-06-11 12:22:48 +02:00
printk printk: Fix panic caused by passing log_buf_len to command line 2018-11-13 11:17:01 -08:00
rcu rcuperf: Fix cleanup path for invalid perf_type strings 2019-05-31 06:48:30 -07:00
sched sched/core: Handle overflow in cpu_shares_write_u64 2019-05-31 06:48:22 -07:00
time timer_list: Guard procfs specific code 2019-08-04 09:33:21 +02:00
trace tracing/snapshot: Resize spare buffer if size changed 2019-08-04 09:33:26 +02:00
.gitignore
acct.c kernel/acct.c: fix the acct->needcheck check in check_free_space() 2018-01-10 09:29:51 +01:00
async.c kernel/async.c: revert "async: simplify lowest_in_progress()" 2018-02-17 13:21:18 +01:00
audit.c audit: return on memory error to avoid null pointer dereference 2018-05-30 07:50:49 +02:00
audit.h Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit 2016-07-29 17:54:17 -07:00
audit_fsnotify.c
audit_tree.c audit: cleanup prune_tree_thread 2016-04-04 09:46:47 -04:00
audit_watch.c audit: fix use-after-free in audit_add_watch 2018-09-26 08:36:37 +02:00
auditfilter.c audit: fix a memory leak bug 2019-05-31 06:48:20 -07:00
auditsc.c audit: allow not equal op for audit by executable 2018-08-03 07:55:25 +02:00
backtracetest.c
bounds.c kbuild: fix kernel/bounds.c 'W=1' warning 2018-11-13 11:16:57 -08:00
capability.c ptrace: Capture the ptracer's creds not PT_PTRACE_CAP 2017-01-06 10:40:13 +01:00
cgroup.c cgroup: Fix deadlock in cpu hotplug path 2018-10-13 09:18:56 +02:00
cgroup_freezer.c
cgroup_pids.c cgroup/pids: remove spurious suspicious RCU usage warning 2017-03-26 13:05:58 +02:00
compat.c
configs.c
context_tracking.c
cpu.c cpu/speculation: Warn on unsupported mitigations= parameter 2019-07-10 09:55:39 +02:00
cpu_pm.c
cpuset.c sched/cpuset/pm: Fix cpuset vs. suspend-resume bugs 2017-10-12 11:51:25 +02:00
crash_dump.c
cred.c ptrace: restore smp_rmb() in __ptrace_may_access() 2019-06-22 08:17:18 +02:00
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c kernel/exit.c: release ptraced tasks before zap_pid_ns_processes 2019-02-06 17:33:29 +01:00
extable.c kernel/extable.c: mark core_kernel_text notrace 2017-07-21 07:42:21 +02:00
fork.c fork: record start_time late 2019-01-13 10:03:51 +01:00
freezer.c freezer, oom: check TIF_MEMDIE on the correct task 2016-07-28 16:07:41 -07:00
futex.c futex: Ensure that futex address is aligned in handle_futex_death() 2019-03-27 14:13:03 +09:00
futex_compat.c
groups.c kernel: make groups_sort calling a responsibility group_info allocators 2018-01-10 09:29:52 +01:00
hung_task.c kernel: hung_task.c: disable on suspend 2019-04-20 09:07:52 +02:00
irq_work.c
jump_label.c jump_label: Invoke jump_label_test() via early_initcall() 2017-12-14 09:28:24 +01:00
kallsyms.c
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c kcov: ensure irq code sees a valid area 2018-08-03 07:55:12 +02:00
kexec.c kexec: allow architectures to override boot mapping 2016-08-02 19:35:27 -04:00
kexec_core.c objtool, x86: Add several functions and files to the objtool whitelist 2018-06-05 10:28:57 +02:00
kexec_file.c kexec: fix double-free when failing to relocate the purgatory 2016-09-01 17:52:01 -07:00
kexec_internal.h
kmod.c
kprobes.c kprobes: Fix error check when reusing optimized probes 2019-04-27 09:34:45 +02:00
ksysfs.c kexec: add a kexec_crash_loaded() function 2016-08-02 19:35:30 -04:00
kthread.c kthread, tracing: Don't expose half-written comm when creating kthreads 2018-08-03 07:55:12 +02:00
latencytop.c
Makefile x86/uaccess, kcov: Disable stack protector 2019-06-22 08:17:19 +02:00
membarrier.c Fix: Disable sys_membarrier when nohz_full is enabled 2017-03-12 06:41:45 +01:00
memremap.c mm, devm_memremap_pages: kill mapping "System RAM" support 2019-01-13 10:03:51 +01:00
module-internal.h
module.c module: exclude SHN_UNDEF symbols from kallsyms api 2018-10-03 17:01:48 -07:00
module_signing.c KEYS: Move the point of trust determination to __key_link() 2016-04-11 22:43:43 +01:00
notifier.c
nsproxy.c
padata.c padata: use smp_mb in padata_reorder to avoid orphaned padata jobs 2019-08-04 09:33:28 +02:00
panic.c panic: avoid deadlocks in re-entrant console drivers 2018-12-29 13:40:16 +01:00
params.c
pid.c pidns: disable pid allocation if pid_ns_prepare_proc() is failed in alloc_pid() 2018-04-13 19:47:53 +02:00
pid_namespace.c signal/pid_namespace: Fix reboot_pid_ns to use send_sig not force_sig 2019-08-04 09:33:16 +02:00
profile.c profile: Convert to hotplug state machine 2016-07-15 10:41:42 +02:00
ptrace.c ptrace: Fix ->ptracer_cred handling for PTRACE_TRACEME 2019-07-10 09:55:45 +02:00
range.c
reboot.c
relay.c kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE 2018-05-30 07:50:29 +02:00
resource.c resource: fix integer overflow at reallocation 2018-04-24 09:34:09 +02:00
seccomp.c seccomp: Move speculation migitation control to arch code 2018-05-22 16:58:02 +02:00
signal.c kernel/signal.c: trace_signal_deliver when signal_group_exit 2019-06-11 12:22:43 +02:00
smp.c cpu/hotplug: Fix SMT supported evaluation 2018-08-15 18:14:53 +02:00
smpboot.c kthread/smpboot: do not park in kthread_create_on_cpu() 2016-10-11 15:06:33 -07:00
smpboot.h
softirq.c Mark HI and TASKLET softirq synchronous 2018-08-15 18:14:42 +02:00
stacktrace.c stacktrace, lockdep: Fix address, newline ugliness 2017-02-14 15:25:42 -08:00
stop_machine.c stop_machine: Use raw spinlocks 2018-08-03 07:55:24 +02:00
sys.c kernel/sys.c: prctl: fix false positive in validate_prctl_map() 2019-06-22 08:17:13 +02:00
sys_ni.c x86/pkeys: Fix pkeys build breakage for some non-x86 arches 2016-09-13 14:41:36 +02:00
sysctl.c sysctl: return -EINVAL if val violates minmax 2019-06-22 08:17:11 +02:00
sysctl_binary.c kernel/sysctl_binary.c: use generic UUID library 2016-05-20 17:58:30 -07:00
task_work.c task_work: use READ_ONCE/lockless_dereference, avoid pi_lock if !task_works 2016-08-02 19:35:02 -04:00
taskstats.c taskstats: fix the length of cgroupstats_cmd_get_policy 2016-11-03 16:55:58 -04:00
test_kprobes.c
torture.c torture: Convert torture_shutdown() to hrtimer 2016-08-22 10:01:49 -07:00
tracepoint.c tracepoint: Do not warn on ENOMEM 2018-05-09 09:50:20 +02:00
tsacct.c
ucount.c kernel/ucount.c: mark user_header with kmemleak_ignore() 2017-06-17 06:41:51 +02:00
uid16.c kernel: make groups_sort calling a responsibility group_info allocators 2018-01-10 09:29:52 +01:00
up.c smp: Add function to execute a function synchronously on a CPU 2016-09-05 13:52:39 +02:00
user-return-notifier.c
user.c
user_namespace.c userns: move user access out of the mutex 2018-09-09 20:01:24 +02:00
utsname.c Merge branch 'nsfs-ioctls' into HEAD 2016-09-22 20:00:36 -05:00
utsname_sysctl.c sys: don't hold uts_sem while accessing userspace memory 2018-09-09 20:01:24 +02:00
watchdog.c kernel/watchdog: prevent false hardlockup on overloaded system 2017-06-17 06:41:57 +02:00
watchdog_hld.c kernel/watchdog: prevent false hardlockup on overloaded system 2017-06-17 06:41:57 +02:00
workqueue.c workqueue: use put_device() instead of kfree() 2018-05-30 07:50:36 +02:00
workqueue_internal.h workqueue: Fix NULL pointer dereference 2017-11-15 15:53:17 +01:00