From: Peter Hurley Date: Thu, 7 Aug 2014 11:14:10 +0000 (-0400) Subject: tty: Fix spurious poll() wakeups X-Git-Tag: fixes-for-v3.18-merge-window~14^2~83 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=57087d515441cab49ff02480aa40a09abfe02c78;p=pandora-kernel.git tty: Fix spurious poll() wakeups When the N_TTY line discipline receives data and wakes readers to process the input, polling writers are also mistakenly woken. This is because, although readers and writers are differentiated by different wait queues (tty->read_wait & tty->write_wait), both wait queues are polled together. Thus, reader wakeups without poll flags still cause poll(POLLOUT) to wakeup. For received data, wakeup readers with POLLIN. Preserve the unspecific wakeup in n_tty_packet_mode_flush(), as this action should flag both POLLIN and POLLOUT. Fixes epoll_wait() for edge-triggered EPOLLOUT. Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- Reading git-diff-tree failed