Am 31.10.2015 um 16:24 schrieb Thomas Meyer: > Am Samstag, den 31.10.2015, 16:21 +0100 schrieb Richard Weinberger: >> Am 31.10.2015 um 16:16 schrieb Thomas Meyer: >>> mhh. strange. I didn't see this behaviour on my machine, but my >>> machine >>> is a rare single core system so, likely a race condition while >>> relaying >>> the timer interrupt to the userspace process. >> >> Here I can trigger it by starting UML, logging in and waiting ~5min. >> Then i try to run "top" --> top hangs forever. >> >>> But I'm out of ideas how this could happen! >> >> Maybe some stupid timeslice over/underflow. >> >>> what happens when you send the hanging process a SIGVTALRM signal? >>> does >>> it proceed correctly? >> >> You mean sending SIGVTALRM to the UML host process? > > No, to the hanging userspace process, maybe the uml host process did > receive a timer interrupt, but failed to relay this signal to the > correct userspace process.
Well, this is not what top expects and dies. signal 26 (VTALRM) was caught by top, please see http://www.debian.org/Bugs/Reporting The problem is within UML's scheduler it does not wake top after the nanosleep() expires. Maybe the new clock is too imprecise, dunno. Thanks, //richard ------------------------------------------------------------------------------ _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel