[Cc Pavel in case he has some ideas] On Fri 17-08-18 15:44:27, Mikulas Patocka wrote: > Hi > > I report this crash on ARM64 on the kernel 4.17.11. The reason is that the > function move_freepages_block accesses contiguous runs of > pageblock_nr_pages. The ARM64 firmware sets holes of reserved memory there > and when move_freepages_block stumbles over this hole, it accesses > uninitialized page structures and crashes. > > 00000000-03ffffff : System RAM > 00080000-007bffff : Kernel code > 00820000-00aa3fff : Kernel data > 04200000-bf80ffff : System RAM > bf810000-bfbeffff : reserved > bfbf0000-bfc8ffff : System RAM > bfc90000-bffdffff : reserved > bffe0000-bfffffff : System RAM > c0000000-dfffffff : MEM > c0000000-c00fffff : PCI Bus 0000:01 > c0000000-c0003fff : 0000:01:00.0 > c0000000-c0003fff : nvme > > The bug was already reported here for x86: > https://bugzilla.redhat.com/show_bug.cgi?id=1598462 > > For x86, it was fixed in the kernel 4.17.7 - but I observed it in the > kernel 4.17.11 on ARM64. I also observed it on 4.18-rc kernels running in > KVM virtual machine on ARM when I compiled the guest kernel with 64kB page > size. > > > Unable to handle kernel paging request at virtual address fffffffffffffffe > Mem abort info: > ESR = 0x96000005 > Exception class = DABT (current EL), IL = 32 bits > SET = 0, FnV = 0 > EA = 0, S1PTW = 0 > Data abort info: > ISV = 0, ISS = 0x00000005 > CM = 0, WnR = 0 > swapper pgtable: 4k pages, 39-bit VAs, pgdp = 00000000791c2068 > [fffffffffffffffe] pgd=0000000000000000, pud=0000000000000000 > Internal error: Oops: 96000005 [#1] PREEMPT SMP > Modules linked in: ftdi_sio usbserial fuse vhost_net vhost tun bridge stp llc autofs4 udlfb syscopyarea sysfillrect sysimgblt fb_sys_fops fb font binfmt_misc ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables ipt_MASQUERADE nf_nat_masquerade_ipv4 xt_nat iptable_nat nf_nat_ipv4 iptable_mangle xt_TCPMSS nf_conntrack_ipv4 nf_defrag_ipv4 ipt_REJECT nf_reject_ipv4 xt_tcpudp xt_conntrack xt_multiport iptable_filter ip_tables x_tables pppoe pppox af_packet ppp_generic slhc nls_utf8 nls_cp852 vfat fat hid_generic usbhid hid snd_usb_audio snd_hwdep snd_usbmidi_lib snd_rawmidi snd_pcm snd_timer snd soundcore nf_nat_ftp nf_conntrack_ftp nf_nat nf_conntrack sd_mod ipv6 aes_ce_blk crypto_simd cryptd aes_ce_cipher crc32_ce ghash_ce gf128mul aes_arm64 sha2_ce sha256_arm64 > sha1_ce sha1_generic efivars xhci_plat_hcd xhci_hcd ahci_platform libahci_platform libahci libata usbcore usb_common mvpp2 unix > CPU: 3 PID: 14823 Comm: updatedb.mlocat Not tainted 4.17.11 #16 > Hardware name: Marvell Armada 8040 MacchiatoBin/Armada 8040 MacchiatoBin, BIOS EDK II Jul 30 2018 > pstate: 00000085 (nzcv daIf -PAN -UAO) > pc : move_freepages_block+0xb4/0x160 > lr : steal_suitable_fallback+0xe4/0x188 > sp : ffffffc0add9f570 > x29: ffffffc0add9f570 x28: 0000000000000000 > x27: ffffffffffffff60 x26: ffffff800886ef58 > x25: 0000000000000008 x24: 0000000000000003 > x23: 0000000000000020 x22: 0000000000000000 > x21: 0000000000000003 x20: ffffff800886ed80 > x19: 0000000000000002 x18: ffffffbf02fefe00 > x17: 0000007fa0916380 x16: ffffff80081dc528 > x15: 0000000000000001 x14: 0000000000000020 > x13: 0000000000000068 x12: 0000000000000080 > x11: ffffffbf02fe8020 x10: ffffff800886ef38 > x9 : 0000000000000000 x8 : 0000000000000000 > x7 : 0000000000100000 x6 : ffffffffffffffff > x5 : fffffffffffffffe x4 : ffffffbf02feffc0 > x3 : ffffffc0add9f5ac x2 : 00000000000000a0 > x1 : ffffffbf02fe8000 x0 : ffffff800886ed80 > Process updatedb.mlocat (pid: 14823, stack limit = 0x000000005d2941e3) > Call trace: > move_freepages_block+0xb4/0x160 > get_page_from_freelist+0xad8/0xea8 > __alloc_pages_nodemask+0xac/0x970 > new_slab+0xc0/0x348 > ___slab_alloc.constprop.32+0x2cc/0x350 > __slab_alloc.isra.26.constprop.31+0x24/0x38 > kmem_cache_alloc+0x168/0x198 > spadfs_alloc_inode+0x2c/0x88 > alloc_inode+0x20/0xa0 > iget5_locked+0xf8/0x1c0 > spadfs_iget+0x44/0x4c8 > spadfs_lookup+0x70/0x108 > __lookup_slow+0x78/0x140 > lookup_slow+0x3c/0x60 > walk_component+0x1e4/0x2e0 > path_lookupat.isra.11+0x64/0x1e8 > filename_lookup.part.20+0x6c/0xe8 > user_path_at_empty+0x4c/0x60 > vfs_statx+0x78/0xd8 > sys_newfstatat+0x24/0x48 > el0_svc_naked+0x30/0x34 > Code: f9401026 d10004c5 f24000df 9a8110a5 (f94000a5) > ---[ end trace def2ceafdfecd702 ]--- > note: updatedb.mlocat[14823] exited with preempt_count 1 -- Michal Hocko SUSE Labs
