On Mon, 2016-04-04 at 11:11:12 UTC, Paul Mackerras via Linuxppc-dev wrote: > In check_cpu_pa_features() we check a number of bits in the
Shouldn't we be clearing the user feature there too? The ibm_pa_features array and the logic in scan_features() knows to flip the cpu_user_features bits, it was just never updated to handle cpu_user_features2. So it seems to me that's where the bug is. > ibm,pa-features array and set and clear CPU features based on what > we find. One of these bits is CPU_FTR_TM, the transactional memory > feature bit. > > If this does disable TM at runtime, then we need to tell userspace > about it by clearing the user CPU feature bits. > > Without this patch userspace processes will think they can execute > TM instructions and get killed when they try. > > Signed-off-by: Anton Blanchard <an...@samba.org> > Cc: sta...@vger.kernel.org > Reviewed-by: David Gibson <da...@gibson.dropbear.id.au> > --- > > Michael I've added stable here because I'm seeing this on a number > of distros and would like to get it backported, but I'll leave it up > to you if it should go there. Yeah it should definitely go to stable. Can we pinpoint which commit introduced the bug, I guess whenever the TM support was merged. cheers _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
