bug#24201: 25.1.50; TLS connections sometimes hang

[Lars Ingebrigtsen]

A couple of weeks ago, TLS connections started making Emacs hang.  I've
yet to find a way to reproduce it reliably, but it seems to involve
opening an async TLS connection while opening a synchronous TLS
connection, or something.

strace in these instances shows an infinite loop like this:

[pid 28250] pselect6(27, [4 6 8 9 10 14 15 16 17 18 19 20 22 24 26], [], NULL, 
{0, 0}, {NULL, 8}) = 1 (in [20], left {0, 0})
[pid 28250] pselect6(27, [4 6 8 9 10 14 15 16 17 18 19 20 22 24 26], [], NULL, 
{0, 0}, {NULL, 8}) = 1 (in [20], left {0, 0})
[pid 28250] pselect6(27, [4 6 8 9 10 14 15 16 17 18 19 20 22 24 26], [], NULL, 
{0, 0}, {NULL, 8}) = 1 (in [20], left {0, 0})
[pid 28250] pselect6(27, [4 6 8 9 10 14 15 16 17 18 19 20 22 24 26], [], NULL, 
{0, 0}, {NULL, 8}) = 1 (in [20], left {0, 0})

Does this ring a bell?  If not, I'll try to debug it further.

I think it started happening like two or three weeks ago.


In GNU Emacs 25.1.50.2 (x86_64-unknown-linux-gnu, GTK+ Version 3.14.5)
 of 2016-07-20 built on stories
Repository revision: 60dd094a8c7bdbbff121c99f56f42910534e7cc1
Windowing system distributor 'The X.Org Foundation', version 11.0.11604000
System Description:     Debian GNU/Linux 8.5 (jessie)

Recent messages:
Quit opening connection to news.gmane.org
Quit [2 times]
Mark set
Opening nntp server on news.gmane.org...done
Mark set
Opening nntp server on news.gmane.org...done
Quit
Quit opening connection to news.gmane.org
Quit
Making completion list...

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-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no