On 06/17/2018 10:20 PM, Greg Kroah-Hartman wrote:
On Thu, Jun 14, 2018 at 02:20:29PM -0700, Guenter Roeck wrote:
On Thu, Jun 14, 2018 at 05:09:21PM -0400, Benjamin Gilbert wrote:
Hi,
4.14.48 can cause abnormally small TCP receive windows when the sender is
faster than the receiver; see https://github.com/coreos/bugs/issues/2457 for
details. Reverting "tcp: avoid integer overflows in tcp_rcv_space_adjust()"
fixes it. Backporting 02db55718d53 ("tcp: do not overshoot window_clamp in
tcp_rcv_space_adjust()"), which is its parent commit upstream, also fixes
it.
02db55718d53 applies cleanly, so I would suggest we go along that route
instead of a revert.
Greg - given that the problematic commit is in all stable releases, it would
probably make sense to apply 02db55718d53 to pre-4.14 kernels as well. It
does apply clean to all kernels all the way back to 3.18.y.
Ah, but it breaks the build everywhere, so I've dropped it :(
Sigh. Maybe I'll learn to compile test at some point.
Can someone please backport it? I'll be glad to queue it up then.
Just sent a backport, though with a bit confused subject. I did compile
test it this time with 4.14.y and 4.9.y.
Guenter
