2020-07-02 04:34:13

by Jens Axboe

[permalink] [raw]
Subject: [GIT PULL] io_uring fixes for 5.8-rc4

Hi Linus,

One fix in here, for a regression in 5.7 where a task is waiting in the
kernel for a condition, but that condition won't become true until
task_work is run. The task_work can't be run exactly because the task is
waiting in the kernel, so we'll never make any progress. One example of
that is registering an eventfd and queueing io_uring work, and then the
task goes and waits in eventfd read with the expectation that it'll get
woken (and read an event) when the io_uring request completes. The
io_uring request is finished through task_work, which won't get run
while the task is looping in eventfd read.

Please pull!

The following changes since commit d60b5fbc1ce8210759b568da49d149b868e7c6d3:

io_uring: fix current->mm NULL dereference on exit (2020-06-25 07:20:43 -0600)

are available in the Git repository at:

git://git.kernel.dk/linux-block.git tags/io_uring-5.8-2020-07-01

for you to fetch changes up to ce593a6c480a22acba08795be313c0c6d49dd35d:

io_uring: use signal based task_work running (2020-06-30 12:39:05 -0600)

----------------------------------------------------------------
io_uring-5.8-2020-07-01

----------------------------------------------------------------
Jens Axboe (1):
io_uring: use signal based task_work running

Oleg Nesterov (1):
task_work: teach task_work_add() to do signal_wake_up()

fs/io_uring.c | 32 ++++++++++++++++++++++++--------
include/linux/sched/jobctl.h | 4 +++-
include/linux/task_work.h | 5 ++++-
kernel/signal.c | 10 +++++++---
kernel/task_work.c | 16 ++++++++++++++--
5 files changed, 52 insertions(+), 15 deletions(-)

--
Jens Axboe


2020-07-02 22:32:37

by pr-tracker-bot

[permalink] [raw]
Subject: Re: [GIT PULL] io_uring fixes for 5.8-rc4

The pull request you sent on Wed, 1 Jul 2020 22:30:24 -0600:

> git://git.kernel.dk/linux-block.git tags/io_uring-5.8-2020-07-01

has been merged into torvalds/linux.git:
https://git.kernel.org/torvalds/c/c93493b7cd40c20708e3373a7cc8e8049460d7ce

Thank you!

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