On 8/2/18 3:22 PM, Kees Cook wrote: > On Thu, Aug 2, 2018 at 12:22 PM, Srivatsa S. Bhat > wrote: >> On 7/26/18 4:09 PM, Kees Cook wrote: >>> On Tue, Jul 24, 2018 at 3:02 PM, Jiri Kosina wrote: >>>> On Tue, 24 Jul 2018, Srivatsa S. Bhat wrote: >>>> >>>>> However, if you are proposing that you'd like to contribute the enhanced >>>>> PTI/Spectre (upstream) patches from the SLES 4.4 tree to 4.4 stable, and >>>>> have them merged instead of this patch series, then I would certainly >>>>> welcome it! >>>> >>>> I'd in principle love us to push everything back to 4.4, but there are a >>>> few reasons (*) why that's not happening shortly. >>>> >>>> Anyway, to point out explicitly what's really needed for those folks >>>> running 4.4-stable and relying on PTI providing The Real Thing(TM), it's >>>> either a 4.4-stable port of >>>> >>>> http://kernel.suse.com/cgit/kernel-source/plain/patches.suse/x86-entry-64-use-a-per-cpu-trampoline-stack.patch?id=3428a77b02b1ba03e45d8fc352ec350429f57fc7 >>>> >>>> or making THREADINFO_GFP imply __GFP_ZERO. >>> >>> This is true in Linus's tree now. Should be trivial to backport: >>> https://git.kernel.org/linus/e01e80634ecdd >>> >> >> Hi Jiri, Kees, >> >> Thank you for suggesting the patch! I have attached the (locally >> tested) 4.4 and 4.9 backports of that patch with this mail. (The >> mainline commit applies cleanly on 4.14). >> >> Greg, could you please consider including them in stable 4.4, 4.9 >> and 4.14? > > I don't think your v4.9 is sufficient: it leaves the vmapped stack > uncleared. v4.9 needs ca182551857 ("kmemleak: clear stale pointers > from task stacks") included in the backport (really, just adding the > memset()). > Ah, I see, thank you! I have attached the updated patchset for 4.9 with this mail. > Otherwise, yup, looks good. > Thank you for reviewing the patches! Regards, Srivatsa VMware Photon OS