io_uring fix for 5.8-rc4

Hi Linus,

Andres reported a regression with the fix that was merged earlier this week, where his setup of using signals to interrupt io_uring CQ waits no longer worked correctly. Fix this, and also limit our use of TWA_SIGNAL to the case where we need it, and continue using TWA_RESUME for task_work as before.

Since the original is marked for 5.7 stable, let's flush this one out before -rc4 is tagged.

Please pull!

The following changes since commit ce593a6c480a22acba08795be313c0c6d49dd35d:

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

are available in the Git repository at:

git://git.kernel.dk/linux-block.git tags/io_uring-5.8-2020-07-05

for you to fetch changes up to b7db41c9e03b5189bc94993bd50e4506ac9e34c1:

io_uring: fix regression with always ignoring signals in io_cqring_wait() (2020-07-04 13:44:45 -0600)

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io_uring-5.8-2020-07-05

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Jens Axboe (1):
io_uring: fix regression with always ignoring signals in io_cqring_wait()

 fs/io_uring.c | 29 ++++++++++++++++++++++-------
 1 file changed, 22 insertions(+), 7 deletions(-)

Jens Axboe