On Mon, Aug 20, 2018 at 01:18:43PM -0700, Andi Kleen wrote: > On Mon, Aug 20, 2018 at 11:03:53AM -0700, Andi Kleen wrote: > > On Mon, Aug 20, 2018 at 06:29:38PM +0200, Michal Hocko wrote: > > > On Fri 17-08-18 15:27:33, Guenter Roeck wrote: > > > > Hi, > > > > > > > > the following crash is seen in v4.4.148, v4.4.149, v4.9.120, and > > > > v4.9.121 > > > > with CONFIG_TRANSPARENT_HUGEPAGE=y, > > > > CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y. > > > > > > Could you try to apply fd7e315988b7 ("x86/mm: Simplify p[g4um]d_page() > > > macros"). I do not see it in stable 4.4 tree and it has been introduced > > > much later in 4.14. This one gave us quite some headache because it is > > > soooo easy to overlook. > > > > Good catch! > > > > I tested that with 4.9 and backporting the patch indeed fixes the > > syzcaller test case running in a KVM VM. Backported patch appended. > > Tested on 4.4 too and it fixes the syzkaller test case there too. >
Confirmed that the problem is fixed in v4.4.151-rc1 and v4.9.123-rc1. Thanks a lot for tracking this down and backporting the fix! Guenter