155bc9505d
Right now io_uring will not actively inform userspace if a CQE is dropped. This is extremely rare, requiring a CQ ring overflow, as well as a GFP_ATOMIC kmalloc failure. However the consequences could cause for example applications to go into an undefined state, possibly waiting for a CQE that never arrives. Return an error code (EBADR) in these cases. Since this is expected to be incredibly rare, try and avoid as much as possible affecting the hot code paths, and so it only is returned lazily and when there is no other available CQEs. Once the error is returned, reset the error condition assuming the user is either ok with it or will clean up appropriately. Signed-off-by: Dylan Yudaken <dylany@fb.com> Link: https://lore.kernel.org/r/20220421091345.2115755-6-dylany@fb.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.