Drivers: hv: vmbus: finally fix hv_need_to_signal_on_read()

Commit a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in
hv_need_to_signal_on_read()")
added the proper mb(), but removed the test "prev_write_sz < pending_sz"
when making the signal decision.

As a result, the guest can signal the host unnecessarily,
and then the host can throttle the guest because the host
thinks the guest is buggy or malicious; finally the user
running stress test can perceive intermittent freeze of
the guest.

This patch brings back the test, and properly handles the
in-place consumption APIs used by NetVSC (see get_next_pkt_raw(),
put_pkt_raw() and commit_rd_index()).

Fixes: a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in
hv_need_to_signal_on_read()")

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reported-by: Rolf Neugebauer <rolf.neugebauer@docker.com>
Tested-by: Rolf Neugebauer <rolf.neugebauer@docker.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

path: root/AUTHORS

Joe Steffen - Creator of Cscope
Hans-Bernhard Broeker <broeker@physik.rwth-aachen.de> - Maintainer
Petr Sorfa <petr@users.sourceforge.net> - Initial OpenSource Maintainer
Simon Cozens - autoconf setup
garp@digi.com - .cc .hh support
jens persson <cscope@persson.cx> - new man page
Edgar Toernig - cscope stability
Martin Kraemer - various improvments
Joshua Uziel <uzi@linuxcare.com>  - code clean up, -h and -k options, and lots more (including autoconf)
Mike Hopkirk <hops@sco.com> - osr5 build, ocs
Darrylo Okahata <darrylo@users.sourceforge.net> - code quality improvements
Brent Verner <brent@rcfile.org> - -R option to recurse sub directories
Thomas Klausner - NetBSD support
Andrew Sharpe - progress bar, tab between line selection and prompts and more
Carl Mascott - FreeBSD support
Rich Salz - Allow -i accept stdio as input as "-"
Stephane Fritsch - BeOS support
Andy Newman <atrn> - FreeBSD support patch
Sascha Blank - FreeBSD support
Bruce Frost - Stability
Chuck Marco and Wilfredo Sanchez - Darwin support
Jason Duell - CSCOPE_EDITOR and CSCOPE_LINEFLAG*, invname database
Tom Hull - Similar work to CSCOPE_EDITOR and friends
Donald Slutz - Various fixes
OGAWA Hirofumi - line mode fixes
Garret Hade - Various ocs fixes
Nick Dixon - Improvement in key handling
Triet H. Lai <thlai@mail.usyd.edu.au> - GNU Emacs fixes for xcscope.el
Steven Elliott <selliott4@austin.rr.com> - Fuzzy pattern matching for xcscope.el
Ragho Mahalingam <ragho@mahalingam.com> - webcscope
Dmitry Obukhov - Hilight code in webcscope
David Cohrs - LEX and SUNOS scanner fix
Valentin Podlovchenko - Overflow prevention and link recursion fix patch
Neil Horman <nhorman@gmail.com>  - Various Bug Fixes