Hi! vv4.19.106-cip21-rt8 should be available at kernel.org. We are only testing kernels in non-realtime configurations, but this proved useful in this case, and uncovered problem on de0-nano (32-bit arm). Bisecting was quite interesting, but in the end we got close enough to guess the guilty commit, and fix was comparatively easy. Thanks for all the help (and that includes upstream). I still need that or equivalent patch merged into -rt tree. Technical details are here: https://git.kernel.org/pub/scm/linux/kernel/git/cip/linux-cip.git/commit/?h=linux-4.19.y-cip-rt&id=1edcec1ee609d349e520e85e7cdfd938f6bafdda Trees are available at https://git.kernel.org/pub/scm/linux/kernel/git/cip/linux-cip.git/log/?h=linux-4.19.y-cip-rt https://git.kernel.org/pub/scm/linux/kernel/git/cip/linux-cip.git/log/?h=linux-4.19.y-cip-rt-rebase And their content should be identical. Best regards, Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html