On Mon, Apr 24, 2017 at 11:50:07AM -0700, Mike Larkin wrote: > On Mon, Apr 24, 2017 at 08:18:17PM +0200, Karl Pettersson wrote: > > I run 64-bit Ubuntu as a vmm guest, according to: > > https://gist.github.com/reyk/6d369c5c0bd0c76f4906f83933f3bb71 > > > > It works well for the most part; I have removed cloud-init becaue I do > > not need it. However, I used Python 2.7 with numpy 1.12 (installed via Pip), > > and experienced crashes which seemed to be related to AVX2 > > instructions, even though the cpu should support this, according to > > /proc/cpuinfo. (cf. https://github.com/numpy/numpy/issues/8128). For > > example, when I tried to reproduce this simple chart, > > https://matplotlib.org/examples/lines_bars_and_markers/fill_demo.html, > > this made Python exit with illegal instruction, according to gdb: > > > > Program received signal SIGILL, Illegal instruction. 0x00007ffff3ce5d56 > > in UBYTE_less_equal_avx2 (args=0x7fffffffba50, dimensions=<optimized > > out>, steps=<optimized out>, __NPY_UNUSED_TAGGEDfunc=<optimized out>) at > > numpy/core/src/umath/loops.c.src:899 > > > > Downgrading to numpy 1.11.1~rc1 (the version available from as an Ubuntu > > package) seems to have fixed the issue. > > > > we filter out avx2 from the guest, for now. >
actually after looking at this it appears we don't, and we should. the filter mask is only for avx (and not the later ones). I'll add suppression of avx2, that may force your software to downgrade to something we do allow. I'll commit that tonight.
