On Mon, Jul 26, 2021 at 11:43 PM Mike Rapoport <rppt@xxxxxxxxxxxxx> wrote: > > On Mon, Jul 26, 2021 at 02:23:20PM -0700, Matt Turner wrote: > > On Mon, Jul 26, 2021 at 1:06 PM Mike Rapoport <rppt@xxxxxxxxxxxxx> wrote: > > > > > > Hi Matt, > > > > > > On Mon, Jul 26, 2021 at 12:27:50PM -0700, Matt Turner wrote: > > > > Reply-To: > > > > > > > > Hi Mike! > > > > > > > > Since commit fa3354e4ea39 (mm: free_area_init: use maximal zone PFNs rather > > > > than zone sizes), I get the following BUG on Alpha (an AlphaServer ES47 Marvel) > > > > and loading userspace leads to a segfault: > > > > > > > > (I didn't notice this for a long time because of other unrelated regressions, > > > > the pandemic, changing jobs, ...) > > > > > > I suspect there will be more surprises down the road :) > > > > > > > BUG: Bad page state in process swapper pfn:2ffc53 > > > > page:fffffc000ecf14c0 refcount:0 mapcount:1 mapping:0000000000000000 index:0x0 > > > > flags: 0x0() > > > > raw: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > > > > raw: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > > > > page dumped because: nonzero mapcount Modules linked in: > > > > CPU: 0 PID: 0 Comm: swapper Not tainted 5.7.0-03841-gfa3354e4ea39-dirty #26 > > > > fffffc0001b5bd68 fffffc0001b5be80 fffffc00011cd148 fffffc000ecf14c0 > > > > fffffc00019803df fffffc0001b5be80 fffffc00011ce340 fffffc000ecf14c0 > > > > 0000000000000000 fffffc0001b5be80 fffffc0001b482c0 fffffc00027d6618 > > > > fffffc00027da7d0 00000000002ff97a 0000000000000000 fffffc0001b5be80 > > > > fffffc00011d1abc fffffc000ecf14c0 fffffc0002d00000 fffffc0001b5be80 > > > > fffffc0001b2350c 0000000000300000 fffffc0001b48298 fffffc0001b482c0 > > > > Trace: > > > > [<fffffc00011cd148>] bad_page+0x168/0x1b0 > > > > [<fffffc00011ce340>] free_pcp_prepare+0x1e0/0x290 > > > > [<fffffc00011d1abc>] free_unref_page+0x2c/0xa0 > > > > [<fffffc00014ee5f0>] cmp_ex_sort+0x0/0x30 > > > > [<fffffc00014ee5f0>] cmp_ex_sort+0x0/0x30 > > > > [<fffffc000101001c>] _stext+0x1c/0x20 > > > > > > > > I haven't tried reproducing this on other machines or QEMU, but I'd be glad to > > > > if that helps. > > > > > > If it's reproducible on QEMU I can debug it locally. > > > > > > > Any ideas? > > > > > > It seems like memory map is not properly initialized. Can you enable > > > CONFIG_DEBUG_MEMORY_INIT and add mminit_debug=4 to the command line. The > > > interesting part of the log would be before "Memory: xK/yK available ..." > > > line. > > > > > > Hopefully it'll give some clues. > > > > Sure thing. Please find attached. > > > aboot: loading uncompressed vmlinuz-5.7.0-03841-gfa3354e4ea39-dirty... > > aboot: loading compressed vmlinuz-5.7.0-03841-gfa3354e4ea39-dirty... > > aboot: PHDR 0 vaddr 0xfffffc0001010000 offset 0xc0 size 0x17c5ae0 > > aboot: bss at 0xfffffc00027d5ae0, size 0xe4ea0 > > aboot: zero-filling 937632 bytes at 0xfffffc00027d5ae0 > > aboot: loading initrd (5965252 bytes/5825 blocks) at 0xfffffc05ff2cc000 > > aboot: starting kernel vmlinuz-5.7.0-03841-gfa3354e4ea39-dirty with arguments ro panic=5 domdadm root=/dev/md1 console=srm mminit_debug=4 > > Linux version 5.7.0-03841-gfa3354e4ea39-dirty (mattst88@ivybridge) (gcc version 11.1.0 (Gentoo 11.1.0-r2 p3), GNU ld (Gentoo 2.36.1 p3) 2.36.1) #26 SMP Sun Jul 25 18:20:06 PDT 2021 > > printk: bootconsole [srm0] enabled > > Booting on Marvel variation Marvel/EV7 using machine vector MARVEL/EV7 from SRM > > Major Options: SMP EV67 VERBOSE_MCHECK DEBUG_SPINLOCK MAGIC_SYSRQ > > Command line: ro panic=5 domdadm root=/dev/md1 console=srm mminit_debug=4 > > memcluster 0, usage 1, start 0, end 1984 > > memcluster 1, usage 0, start 1984, end 1048576 > > memcluster 2, usage 1, start 2097152, end 2097224 > > memcluster 3, usage 0, start 2097224, end 3145728 > > Initial ramdisk at: 0x(____ptrval____) (5965252 bytes) > > Found an IO7 at PID 0 > > Initializing IO7 at PID 0 > > FIXME: disabling master aborts > > FIXME: disabling master aborts > > FIXME: disabling master aborts > > FIXME: disabling master aborts > > SMP: 2 CPUs probed -- cpu_present_mask = 3 > > Zone ranges: > > DMA [mem 0x0000000000f80000-0x00000fffffffdfff] > > Normal empty > > Movable zone start for each node > > Early memory node ranges > > node 0: [mem 0x0000000000f80000-0x00000001ffffffff] > > node 0: [mem 0x0000000400090000-0x00000005ffffffff] > > I think that the issue is that memory marked as used in memcluster is never > added to memblock and it skews node/zone sizing calculations. Thanks, this patch fixes it. With the patch applied, I see Zone ranges: DMA [mem 0x0000000000000000-0x00000fffffffdfff] Normal empty Movable zone start for each node Early memory node ranges node 0: [mem 0x0000000000000000-0x00000001ffffffff] node 0: [mem 0x0000000400000000-0x00000005ffffffff] Initmem setup node 0 [mem 0x0000000000000000-0x00000005ffffffff] If you want to send me this patch with your S-o-b I'll take it through my alpha git tree. Thanks Mike! Matt
