DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 129633858D28
Date: Sat, 9 Apr 2022 20:46:19 +0900
From: Takashi Yano <takashi.yano@nifty.ne.jp>
To: cygwin@cygwin.com
Subject: Re: Deadlock of the process tree when running make
Message-Id: <20220409204619.dd0e53902d5e108ef462e510@nifty.ne.jp>
In-Reply-To: <ab3971adb8f441fd16bb62e480547a95@ispras.ru>
References: <9388316255ada0e0fcb2d849cce5a894@ispras.ru>
 <20220409191743.6da2268a36e8c9b4ab22c722@nifty.ne.jp>
 <1ecd670b1cdff43e0b0d7e5ee4c9cfc5@ispras.ru>
 <ab3971adb8f441fd16bb62e480547a95@ispras.ru>
Mime-Version: 1.0
Precedence: list
Cc: Alexey Izbyshev <izbyshev@ispras.ru>
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Errors-To: cygwin-bounces+archive-cygwin=delorie.com@cygwin.com
Sender: "Cygwin" <cygwin-bounces+archive-cygwin=delorie.com@cygwin.com>

On Sat, 09 Apr 2022 14:02:38 +0300
Alexey Izbyshev wrote:
> On 2022-04-09 14:00, Alexey Izbyshev wrote:
> > On 2022-04-09 13:17, Takashi Yano wrote:
> > 
> >> Attaching gdb to the hanging process and dumping stack by 'bt'
> >> command for each thread may diagnose more detail.
> > 
> > I decided to simply look at assembly at the point shown in
> > ProcessHacker stack trace (cygwin1.dll!feinitialise+0x5ecab) to avoid
> > disturbing the process by gdb. And it's clear that the hang is in
> > fhandler_pty_slave::reset_switch_to_pcon() at [1]. I've checked that
> > there were some changes in that function since 3.3.4. Could they fix
> > this deadlock?
> > 
> > [1] 
> > https://cygwin.com/git/?p=newlib-cygwin.git;a=blob;f=winsup/cygwin/fhandler_tty.cc;h=7bef6958c106c5e78cc90e014081022fd3a205bc;hb=cygwin-3_3_4-release
> > 
> 
> Missed the line in the link above: 
> https://cygwin.com/git?p=newlib-cygwin.git;a=blob;f=winsup/cygwin/fhandler_tty.cc;h=7bef6958c106c5e78cc90e014081022fd3a205bc;hb=cygwin-3_3_4-release#l1199

Thanks for finding that. It would be very helpfull if you could
find another process which holds pcon_mutex and where it is stopping.

-- 
Takashi Yano <takashi.yano@nifty.ne.jp>

-- 
Problem reports:      https://cygwin.com/problems.html
FAQ:                  https://cygwin.com/faq/
Documentation:        https://cygwin.com/docs.html
Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple