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Zhang Wensheng 779b634714 driver core: fix potential deadlock in __driver_attach 
[ Upstream commit 70fe758352 ]

In __driver_attach function, There are also AA deadlock problem,
like the commit b232b02bf3 ("driver core: fix deadlock in
__device_attach").

stack like commit b232b02bf3 ("driver core: fix deadlock in
__device_attach").
list below:
    In __driver_attach function, The lock holding logic is as follows:
    ...
    __driver_attach
    if (driver_allows_async_probing(drv))
      device_lock(dev)      // get lock dev
        async_schedule_dev(__driver_attach_async_helper, dev); // func
          async_schedule_node
            async_schedule_node_domain(func)
              entry = kzalloc(sizeof(struct async_entry), GFP_ATOMIC);
              /* when fail or work limit, sync to execute func, but
                 __driver_attach_async_helper will get lock dev as
                 will, which will lead to A-A deadlock.  */
              if (!entry || atomic_read(&entry_count) > MAX_WORK) {
                func;
              else
                queue_work_node(node, system_unbound_wq, &entry->work)
      device_unlock(dev)

    As above show, when it is allowed to do async probes, because of
    out of memory or work limit, async work is not be allowed, to do
    sync execute instead. it will lead to A-A deadlock because of
    __driver_attach_async_helper getting lock dev.

Reproduce:
and it can be reproduce by make the condition
(if (!entry || atomic_read(&entry_count) > MAX_WORK)) untenable, like
below:

[  370.785650] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables
this message.
[  370.787154] task:swapper/0       state:D stack:    0 pid:    1 ppid:
0 flags:0x00004000
[  370.788865] Call Trace:
[  370.789374]  <TASK>
[  370.789841]  __schedule+0x482/0x1050
[  370.790613]  schedule+0x92/0x1a0
[  370.791290]  schedule_preempt_disabled+0x2c/0x50
[  370.792256]  __mutex_lock.isra.0+0x757/0xec0
[  370.793158]  __mutex_lock_slowpath+0x1f/0x30
[  370.794079]  mutex_lock+0x50/0x60
[  370.794795]  __device_driver_lock+0x2f/0x70
[  370.795677]  ? driver_probe_device+0xd0/0xd0
[  370.796576]  __driver_attach_async_helper+0x1d/0xd0
[  370.797318]  ? driver_probe_device+0xd0/0xd0
[  370.797957]  async_schedule_node_domain+0xa5/0xc0
[  370.798652]  async_schedule_node+0x19/0x30
[  370.799243]  __driver_attach+0x246/0x290
[  370.799828]  ? driver_allows_async_probing+0xa0/0xa0
[  370.800548]  bus_for_each_dev+0x9d/0x130
[  370.801132]  driver_attach+0x22/0x30
[  370.801666]  bus_add_driver+0x290/0x340
[  370.802246]  driver_register+0x88/0x140
[  370.802817]  ? virtio_scsi_init+0x116/0x116
[  370.803425]  scsi_register_driver+0x1a/0x30
[  370.804057]  init_sd+0x184/0x226
[  370.804533]  do_one_initcall+0x71/0x3a0
[  370.805107]  kernel_init_freeable+0x39a/0x43a
[  370.805759]  ? rest_init+0x150/0x150
[  370.806283]  kernel_init+0x26/0x230
[  370.806799]  ret_from_fork+0x1f/0x30

To fix the deadlock, move the async_schedule_dev outside device_lock,
as we can see, in async_schedule_node_domain, the parameter of
queue_work_node is system_unbound_wq, so it can accept concurrent
operations. which will also not change the code logic, and will
not lead to deadlock.

Fixes: ef0ff68351 ("driver core: Probe devices asynchronously instead of the driver")
Signed-off-by: Zhang Wensheng <zhangwensheng5@huawei.com>
Link: https://lore.kernel.org/r/20220622074327.497102-1-zhangwensheng5@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17 14:41:39 +02:00
arch KVM: x86: Fix errant brace in KVM capability handling 2022-08-17 14:41:38 +02:00
block blk-mq: don't create hctx debugfs dir until q->debugfs_dir is created 2022-08-17 14:40:38 +02:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:28:03 +02:00
crypto crypto: memneq - move into lib/ 2022-06-22 14:28:06 +02:00
Documentation media: uapi: HEVC: Change pic_order_cnt definition in v4l2_hevc_dpb_entry 2022-08-17 14:41:06 +02:00
drivers driver core: fix potential deadlock in __driver_attach 2022-08-17 14:41:39 +02:00
fs fs: check FMODE_LSEEK to control internal pipe splicing 2022-08-17 14:41:05 +02:00
include scsi: iscsi: Fix session removal on shutdown 2022-08-17 14:41:38 +02:00
init stack: Declare {randomize_,}kstack_offset to fix Sparse warnings 2022-08-17 14:40:36 +02:00
io_uring io_uring: Don't require reinitable percpu_ref 2022-08-17 14:40:42 +02:00
ipc ipc/mqueue: use get_tree_nodev() in mqueue_get_tree() 2022-06-09 10:30:30 +02:00
kernel wireguard: ratelimiter: use hrtimer in selftest 2022-08-17 14:41:16 +02:00
lib lib/test_hmm: avoid accessing uninitialized pages 2022-08-17 14:41:37 +02:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm mm/memremap: fix memunmap_pages() race with get_dev_pagemap() 2022-08-17 14:41:37 +02:00
net dccp: put dccp_qpolicy_full() and dccp_qpolicy_push() in the same lock 2022-08-17 14:41:16 +02:00
samples samples/landlock: Format with clang-format 2022-06-09 10:30:46 +02:00
scripts kbuild: Fix include path in scripts/Makefile.modpost 2022-08-17 14:40:34 +02:00
security selinux: Add boundary check in put_entry() 2022-08-17 14:40:26 +02:00
sound ALSA: hda/realtek: Add a quirk for HP OMEN 15 (8786) mute LED 2022-08-17 14:40:07 +02:00
tools libbpf: fix an snprintf() overflow check 2022-08-17 14:41:09 +02:00
usr Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
virt KVM: Don't set Accessed/Dirty bits for ZERO_PAGE 2022-08-17 14:41:37 +02:00
.clang-format genirq/msi: Make interrupt allocation less convoluted 2021-12-16 22:22:20 +01:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap hotfixes for 5.18-rc7 2022-05-13 10:22:37 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: replace a Microchip AT91 maintainer 2022-02-09 11:30:01 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS io_uring: move to separate directory 2022-08-17 14:40:41 +02:00
Makefile io_uring: move to separate directory 2022-08-17 14:40:41 +02:00
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