No description
  • C 98.2%
  • Assembly 1%
  • Makefile 0.3%
  • Shell 0.2%
  • Python 0.1%
Find a file
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Liming Sun c79fff3feb platform/mellanox: fix potential deadlock in the tmfifo driver
commit 638bc4ca3d28c25986cce4cbad69d9b8abf1e434 upstream.

This commit fixes the potential deadlock caused by the console Rx
and Tx processing at the same time. Rx and Tx both take the console
and tmfifo spinlock but in different order which causes potential
deadlock. The fix is to use different tmfifo spinlock for Rx and
Tx since they protect different resources and it's safe to split
the lock.

Below is the reported call trace when copying/pasting large string
in the console.

Rx:
    _raw_spin_lock_irqsave (hvc lock)
    __hvc_poll
    hvc_poll
    in_intr
    vring_interrupt
    mlxbf_tmfifo_rxtx_one_desc (tmfifo lock)
    mlxbf_tmfifo_rxtx
    mlxbf_tmfifo_work_rxtx
Tx:
    _raw_spin_lock_irqsave (tmfifo lock)
    mlxbf_tmfifo_virtio_notify
    virtqueue_notify
    virtqueue_kick
    put_chars
    hvc_push
    hvc_write (hvc lock)
    ...
    do_tty_write
    tty_write

Fixes: 1357dfd726 ("platform/mellanox: Add TmFifo driver for Mellanox BlueField Soc")
Cc: <stable@vger.kernel.org> # 5.4+
Reviewed-by: David Woods <dwoods@mellanox.com>
Signed-off-by: Liming Sun <lsun@mellanox.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-17 19:48:42 +01:00
arch
block
certs
crypto
Documentation
drivers platform/mellanox: fix potential deadlock in the tmfifo driver 2020-01-17 19:48:42 +01:00
fs afs: Fix afs_lookup() to not clobber the version on a new dentry 2020-01-17 19:48:41 +01:00
include afs: Fix use-after-loss-of-ref 2020-01-17 19:48:41 +01:00
init
ipc
kernel keys: Fix request_key() cache 2020-01-17 19:48:42 +01:00
lib
LICENSES
mm uaccess: Add non-pagefault user-space write function 2020-01-17 19:48:40 +01:00
net bpf: skmsg, fix potential psock NULL pointer dereference 2020-01-17 19:48:40 +01:00
samples
scripts bpf: Support pre-2.25-binutils objcopy for vmlinux BTF 2020-01-17 19:48:41 +01:00
security
sound
tools libbpf: Fix Makefile' libbpf symbol mismatch diagnostic 2020-01-17 19:48:41 +01:00
usr
virt
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS
Makefile
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.