Hi, On Mon, Jan 04, 2021 at 02:03:00PM -0500, Qian Cai wrote: > On Wed, 2020-12-09 at 23:43 +0200, Mike Rapoport wrote: > > From: Mike Rapoport <rppt@xxxxxxxxxxxxx> > > > > Interleave initialization of pages that correspond to holes with the > > initialization of memory map, so that zone and node information will be > > properly set on such pages. > > > > Fixes: 73a6e474cb37 ("mm: memmap_init: iterate over memblock regions rather > > that check each PFN") > > Reported-by: Andrea Arcangeli <aarcange@xxxxxxxxxx> > > Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> > > Reverting this commit on the top of today's linux-next fixed a crash while > reading /proc/kpagecount on a NUMA server. Can you please post the entire dmesg? Is it possible to get the pfn that triggered the crash? > [ 8858.006726][T99897] BUG: unable to handle page fault for address: fffffffffffffffe > [ 8858.014814][T99897] #PF: supervisor read access in kernel mode > [ 8858.020686][T99897] #PF: error_code(0x0000) - not-present page > [ 8858.026557][T99897] PGD 1371417067 P4D 1371417067 PUD 1371419067 PMD 0 > [ 8858.033224][T99897] Oops: 0000 [#1] SMP KASAN NOPTI > [ 8858.038710][T99897] CPU: 28 PID: 99897 Comm: proc01 Tainted: G O 5.11.0-rc1-next-20210104 #1 > [ 8858.048515][T99897] Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 03/09/2018 > [ 8858.057794][T99897] RIP: 0010:kpagecount_read+0x1be/0x5e0 > PageSlab at include/linux/page-flags.h:342 > (inlined by) kpagecount_read at fs/proc/page.c:69 -- Sincerely yours, Mike.