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Duoming Zhou b413b0cb00 NFC: hci: fix sleep in atomic context bugs in nfc_hci_hcp_message_tx
There are sleep in atomic context bugs when the request to secure
element of st21nfca is timeout. The root cause is that kzalloc and
alloc_skb with GFP_KERNEL parameter and mutex_lock are called in
st21nfca_se_wt_timeout which is a timer handler. The call tree shows
the execution paths that could lead to bugs:

   (Interrupt context)
st21nfca_se_wt_timeout
  nfc_hci_send_event
    nfc_hci_hcp_message_tx
      kzalloc(..., GFP_KERNEL) //may sleep
      alloc_skb(..., GFP_KERNEL) //may sleep
      mutex_lock() //may sleep

This patch moves the operations that may sleep into a work item.
The work item will run in another kernel thread which is in
process context to execute the bottom half of the interrupt.
So it could prevent atomic context from sleeping.

Fixes: 2130fb97fe ("NFC: st21nfca: Adding support for secure element")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220518115733.62111-1-duoming@zju.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-19 17:54:02 -07:00
Documentation Documentation: add description for net.core.gro_normal_batch 2022-05-19 17:46:23 -07:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
arch Merge branch 'arm/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc 2022-05-18 14:07:43 -10:00
block block/mq-deadline: Set the fifo_time member also if inserting at head 2022-05-13 17:02:46 -06:00
certs Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
crypto for-5.18/64bit-pi-2022-03-25 2022-03-26 12:01:35 -07:00
drivers NFC: hci: fix sleep in atomic context bugs in nfc_hci_hcp_message_tx 2022-05-19 17:54:02 -07:00
fs io_uring-5.18-2022-05-18 2022-05-18 14:21:30 -10:00
include net: macb: Fix PTP one step sync support 2022-05-19 16:58:16 -07:00
init Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
ipc fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
kernel audit,io_uring,io-wq: call __audit_uring_exit for dummy contexts 2022-05-17 15:03:36 -04:00
lib Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2022-05-18 14:02:25 -10:00
mm hotfixes for 5.18-rc7 2022-05-13 10:22:37 -07:00
net Networking fixes for 5.18-rc8, including fixes from can, xfrm and 2022-05-19 05:50:29 -10:00
samples sched/tracing: Append prev_state to tp args instead 2022-05-12 00:37:11 +02:00
scripts objtool: Enable unreachable warnings for CLANG LTO 2022-04-19 21:58:48 +02:00
security selinux: fix bad cleanup on error in hashtab_duplicate() 2022-05-17 18:34:35 -04:00
sound ALSA: usb-audio: Restore Rane SL-1 quirk 2022-05-16 12:41:13 +02:00
tools Networking fixes for 5.18-rc8, including fixes from can, xfrm and 2022-05-19 05:50:29 -10:00
usr Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
virt Merge branch 'kvm-fixes-for-5.18-rc5' into HEAD 2022-04-29 12:39:34 -04:00
.clang-format genirq/msi: Make interrupt allocation less convoluted 2021-12-16 22:22:20 +01:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.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 Merge branch 'arm/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc 2022-05-18 14:07:43 -10:00
Makefile Linux 5.18-rc7 2022-05-15 18:08:58 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README

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.