a76c0b31ee
For recv/recvmsg, IO either completes immediately or gets queued for a
retry. This isn't the case for read/readv, if eg a normal file or a block
device is used. Here, an operation can get queued with the block layer.
If this happens, ring mapped buffers must get committed immediately to
avoid that the next read can consume the same buffer.
Check if we're dealing with pollable file, when getting a new ring mapped
provided buffer. If it's not, commit it immediately rather than wait post
issue. If we don't wait, we can race with completions coming in, or just
plain buffer reuse by committing after a retry where others could have
grabbed the same buffer.
Fixes: c7fb19428d67 ("io_uring: add support for ring mapped supplied buffers")
Reviewed-by: Hao Xu <howeyxu@tencent.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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.