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Longpeng(Mike) f7eb42acb1 vsock/virtio: avoid potential deadlock when vsock device remove
[ Upstream commit 49b0b6ffe20c5344f4173f3436298782a08da4f2 ]

There's a potential deadlock case when remove the vsock device or
process the RESET event:

  vsock_for_each_connected_socket:
      spin_lock_bh(&vsock_table_lock) ----------- (1)
      ...
          virtio_vsock_reset_sock:
              lock_sock(sk) --------------------- (2)
      ...
      spin_unlock_bh(&vsock_table_lock)

lock_sock() may do initiative schedule when the 'sk' is owned by
other thread at the same time, we would receivce a warning message
that "scheduling while atomic".

Even worse, if the next task (selected by the scheduler) try to
release a 'sk', it need to request vsock_table_lock and the deadlock
occur, cause the system into softlockup state.
  Call trace:
   queued_spin_lock_slowpath
   vsock_remove_bound
   vsock_remove_sock
   virtio_transport_release
   __vsock_release
   vsock_release
   __sock_release
   sock_close
   __fput
   ____fput

So we should not require sk_lock in this case, just like the behavior
in vhost_vsock or vmci.

Fixes: 0ea9e1d3a9 ("VSOCK: Introduce virtio_transport.ko")
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210812053056.1699-1-longpeng2@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-05 18:54:39 +02:00
arch ARC: fp: set FPU_STATUS.FWE to enable FPU_STATUS update on context switch 2024-07-05 18:53:59 +02:00
block blk-iolatency: error out if blk_get_queue() failed in iolatency_set_limit() 2024-07-05 18:52:09 +02:00
certs certs: add 'x509_revocation_list' to gitignore 2021-07-20 16:05:35 +02:00
crypto init: add dsm gpl source 2024-07-05 18:00:04 +02:00
Documentation init: add dsm gpl source 2024-07-05 18:00:04 +02:00
drivers xen/events: Fix race in set_evtchn_to_irq 2024-07-05 18:54:39 +02:00
fs cifs: create sd context must be a multiple of 8 2024-07-05 18:53:59 +02:00
include net: igmp: increase size of mr_ifc_count 2024-07-05 18:54:39 +02:00
init init: add dsm gpl source 2024-07-05 18:00:04 +02:00
ipc
kernel bpf: Fix integer overflow involving bucket_size 2024-07-05 18:54:12 +02:00
lib init: add dsm gpl source 2024-07-05 18:00:04 +02:00
LICENSES
mm init: add dsm gpl source 2024-07-05 18:00:04 +02:00
net vsock/virtio: avoid potential deadlock when vsock device remove 2024-07-05 18:54:39 +02:00
samples samples/bpf: Fix the error return code of xdp_redirect's main() 2021-07-14 16:56:23 +02:00
scripts scripts/tracing: fix the bug that can't parse raw_trace_func 2024-07-05 18:52:27 +02:00
security bpf: Add lockdown check for probe_write_user helper 2024-07-05 18:53:10 +02:00
sound ASoC: cs42l42: Fix LRCLK frame start edge 2024-07-05 18:54:11 +02:00
SynoBuildConf init: add dsm gpl source 2024-07-05 18:00:04 +02:00
synology init: add dsm gpl source 2024-07-05 18:00:04 +02:00
tools libbpf: Fix probe for BPF_PROG_TYPE_CGROUP_SOCKOPT 2024-07-05 18:54:12 +02:00
usr
virt KVM: Do not leak memory for duplicate debugfs directories 2024-07-05 18:52:31 +02:00
.clang-format init: add dsm gpl source 2024-07-05 18:00:04 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap mailmap: add two more addresses of Uwe Kleine-König 2020-12-06 10:19:07 -08:00
COPYING
CREDITS
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 init: add dsm gpl source 2024-07-05 18:00:04 +02:00
Makefile init: add dsm gpl source 2024-07-05 18:00:04 +02:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.