On Tue, 2019-10-15 at 20:51 +0530, Anshuman Khandual wrote: > > On 10/15/2019 08:11 PM, Qian Cai wrote: > > The x86 will crash with linux-next during boot due to this series (v5) with the > > config below plus CONFIG_DEBUG_VM_PGTABLE=y. I am not sure if v6 would address > > it. > > > > https://raw.githubusercontent.com/cailca/linux-mm/master/x86.config > > > > [ 33.862600][ T1] page:ffffea0009000000 is uninitialized and poisoned > > [ 33.862608][ T1] raw: ffffffffffffffff ffffffffffffffff ffffffffffffffff > > ffffff871140][ T1] ? _raw_spin_unlock_irq+0x27/0x40 > > [ 33.871140][ T1] ? rest_init+0x307/0x307 > > [ 33.871140][ T1] kernel_init+0x11/0x139 > > [ 33.871140][ T1] ? rest_init+0x307/0x307 > > [ 33.871140][ T1] ret_from_fork+0x27/0x50 > > [ 33.871140][ T1] Modules linked in: > > [ 33.871140][ T1] ---[ end trace e99d392b0f7befbd ]--- > > [ 33.871140][ T1] RIP: 0010:alloc_gigantic_page_order+0x3fe/0x490 > > Hmm, with defconfig (DEBUG_VM=y and DEBUG_VM_PGTABLE=y) it does not crash but > with the config above, it does. Just wondering if it is possible that these > pages might not been initialized yet because DEFERRED_STRUCT_PAGE_INIT=y ? Yes, this patch works fine. diff --git a/init/main.c b/init/main.c index 676d8020dd29..591be8f9e8e0 100644 --- a/init/main.c +++ b/init/main.c @@ -1177,7 +1177,6 @@ static noinline void __init kernel_init_freeable(void) workqueue_init(); init_mm_internals(); - debug_vm_pgtable(); do_pre_smp_initcalls(); lockup_detector_init(); @@ -1186,6 +1185,8 @@ static noinline void __init kernel_init_freeable(void) sched_init_smp(); page_alloc_init_late(); + debug_vm_pgtable(); + /* Initialize page ext after all struct pages are initialized. */ page_ext_init(); > > [ 13.898549][ T1] page:ffffea0005000000 is uninitialized and poisoned > [ 13.898549][ T1] raw: ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff > [ 13.898549][ T1] raw: ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff > [ 13.898549][ T1] page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p)) > [ 13.898549][ T1] ------------[ cut here ]------------ > [ 13.898549][ T1] kernel BUG at ./include/linux/mm.h:1107! > [ 13.898549][ T1] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI > [ 13.898549][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.4.0-rc3-next-20191015+ #
