8751853091
swap_readpage() sets waiter = bio->bi_private even if synchronous = F, this means that the caller can get the spurious wakeup after return. This can be fatal if blk_wake_io_task() does set_current_state(TASK_RUNNING) after the caller does set_special_state(), in the worst case the kernel can crash in do_task_dead(). Link: http://lkml.kernel.org/r/20190704160301.GA5956@redhat.com Fixes: 0619317ff8baa2d ("block: add polled wakeup task helper") Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reported-by: Qian Cai <cai@lca.pw> Acked-by: Hugh Dickins <hughd@google.com> Reviewed-by: Jens Axboe <axboe@kernel.dk> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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.