Hi, On 17/02/17 18:08, Norbert Lange wrote: > Hello, > > Tried reproducing it at work (where it first happened on a build server). > On my PC at home with 4 cores / 12 thread the bug reproduces always > On a 6 core / 12 threads Xeon Server the bug reproduces always > On my work PC with 4 cores / 4 threads running in a VMware Instance it > doesnt reproduce. > All running Debian Stretch with current updates. > > Maybe you want to add infos about your system? > From the sample of 3: Hyperthreading or >= 8 threads or runnin on bare > metal instead of in a VM could provoke the bug.
Originally the system I tried it on has 8 cores (can't remember number of threads), but I tried it on machines with 2 cores and one with 16 and it worked on all of them. I don't think the number of cores is relevant here. > Further make 4.1 was uploaded to Debian Stretch on 16h january, the > issue appeared on 19th january on the server. > So disregard what I said about this not being an upstream issue - its > actually quite possible. Have you muddled years up here? 4.1 was uploaded on 16th Jan *2016*. > Heres a dump via attached gdb (step wont do anything so it seems that > the thread is blocked): > > (gdb) thread apply all bt > > Thread 1 (process 12177): > #0 0x00007f476c156962 in do_fcntl (fd=1, cmd=7, arg=0x5595eae95ea0) > at ../sysdeps/unix/sysv/linux/fcntl.c:31 This is fcntl(stdout = /dev/null, F_SETLKW, <struct flock>) It seems that "make -O" attempts to lock stdout before writing to it so that multiple make processes can cooperate on who gets to write any output. If it's hanging here, then someone must already be holding the lock. Please can you give the output of "lslocks" on the machines that fail. There might be an entry for /dev/null which will point at the culprit. Failing that, an "strace -f" would be useful so we can see all the calls made to fcntl. > I`ll have to compile make with debuginfo if you need more (gonna take > a few days) I don't need any debug information, but you may be interested in this: https://wiki.debian.org/AutomaticDebugPackages So if you add this apt source: deb http://deb.debian.org/debian-debug/ unstable-debug main You can then install make-dbgsym to get the debug symbols for make without recompiling anything. Thanks, James > 2017-02-17 15:24 GMT+01:00 James Cowgill <jcowg...@debian.org>: >> On 16/02/17 21:52, Norbert Lange wrote: >>> Package: make >>> Version: 4.1-9 >>> Severity: important >>> >>> Dear Maintainer, >>> >>> running the attached Makefile will hang the process, >>> if multiple jobs are used then the process wont respond to a >>> TERM and has to be killed. >>> >>> The very same issue is observed with make-guile. >>> >>> I believe this to not be an upstream bug, since I observed this >>> only a couple weeks ago after an upgrade. >>> Unfortunatly I can`t pinpoint a date or version. >> >> I cannot reproduce this bug. >> >> Also, make has not been updated in testing for almost a year so if it >> only started happening recently, something else probably caused it. >> >> Running 'make -d -O' (although this may be difficult if the bug requires >> redirection to /dev/null) or the output or running make inside gdb and >> finding where it hangs might help in diagnosing this. >> >> Thanks, >> James
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