On Tue, Apr 25, 2017 at 2:25 AM, Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> wrote: > remove_pagetable() does page walk using p*d_page_vaddr() plus cast. > It's not canonical approach -- we usually use p*d_offset() for that. > > It works fine as long as all page table levels are present. We broke the > invariant by introducing folded p4d page table level. > > As result, remove_pagetable() interprets PMD as PUD and it leads to > crash: > > BUG: unable to handle kernel paging request at ffff880300000000 > IP: memchr_inv+0x60/0x110 > PGD 317d067 > P4D 317d067 > PUD 3180067 > PMD 33f102067 > PTE 8000000300000060 > > Let's fix this by using p*d_offset() instead of p*d_page_vaddr() for > page walk. > > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > Reported-by: Dan Williams <dan.j.williams@xxxxxxxxx> > Fixes: f2a6a7050109 ("x86: Convert the rest of the code to support p4d_t") Thanks! This patch on top of tip/master passes a full run of the nvdimm regression suite. Tested-by: Dan Williams <dan.j.williams@xxxxxxxxx> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>