Re: [PATCH v3] m68k: Fix memblock-related crashes

From: Andreas Schwab
Date: Thu Dec 13 2018 - 12:46:00 EST


I'm now getting this Oops:

[ 65.390000] Unable to handle kernel NULL pointer dereference at virtual address (ptrval)
[ 65.390000] Oops: 00000000
[ 65.390000] Modules linked in: nls_iso8859_1 nls_cp437 vfat fat virtio_rng virtio_blk virtio_ring virtio xfs btrfs xor zlib_deflate raid6_pq libcrc32c reiserfs squashfs fuse dm_snapshot dm_bufio dm_mod binfmt_misc loop sg
[ 65.390000] PC: [<00211544>] blk_throtl_bio+0x10e/0x592
[ 65.390000] SR: 2700 SP: (ptrval) a2: bf506dc0
[ 65.390000] d0: 00000001 d1: 03ce63fb d2: 00000000 d3: 00000016
[ 65.390000] d4: ffffa45b d5: 00000000 a0: 00000000 a1: 00000000
[ 65.390000] Process mkswap (pid: 289, task=(ptrval))
[ 65.390000] Frame format=7 eff addr=00000060 ssw=0505 faddr=00000060
[ 65.390000] wb 1 stat/addr/data: 0000 00000000 00000000
[ 65.390000] wb 2 stat/addr/data: 0000 00000000 00000000
[ 65.390000] wb 3 stat/addr/data: 0000 00000060 0001dba1
[ 65.390000] push data: 00000000 00000000 00000000 00000000
[ 65.390000] Stack from bd1b7bdc:
[ 65.390000] 00000008 00080000 ffffffff 00000002 ffffffff 00000006 bd6e0b40 bf596c18
[ 65.390000] 00682988 bd1b7c78 006000c0 00000003 00000000 00000080 00000005 001f28e4
[ 65.390000] bf596c18 bf4f1800 bd6e0b40 00000008 00080000 00000000 00001000 000a1848
[ 65.390000] 00000001 bd6e0b40 bf596c18 bd1b7e24 00080000 00000008 bf4f1800 bf596c18
[ 65.390000] bd1b7e24 bd1b7cec 00000001 bd1b7d3a 00095c52 0010ce96 000a1848 bd1b7cec
[ 65.390000] 001f3ea8 bd6e0b40 00000008 00080000 00000000 bd6e0b40 027616cc bd1b7e24
[ 65.390000] Call Trace: [<00080000>] check_ids+0x8/0x64
[ 65.390000] [<001f28e4>] generic_make_request_checks+0x3ca/0x4ee
[ 65.390000] [<00080000>] check_ids+0x8/0x64
[ 65.390000] [<00001000>] kernel_pg_dir+0x0/0x1000
[ 65.390000] [<000a1848>] __put_page+0x0/0x32
[ 65.390000] [<00080000>] check_ids+0x8/0x64
[ 65.390000] [<00095c52>] add_to_page_cache_lru+0x0/0xc4
[ 65.390000] [<0010ce96>] do_mpage_readpage+0x0/0x5cc
[ 65.390000] [<000a1848>] __put_page+0x0/0x32
[ 65.390000] [<001f3ea8>] generic_make_request+0x32/0x23c
[ 65.390000] [<00080000>] check_ids+0x8/0x64
[ 65.390000] [<001f417c>] submit_bio+0xca/0xfc
[ 65.390000] [<00095c52>] add_to_page_cache_lru+0x0/0xc4
[ 65.390000] [<0010ce96>] do_mpage_readpage+0x0/0x5cc
[ 65.390000] [<00095c52>] add_to_page_cache_lru+0x0/0xc4
[ 65.390000] [<0010ce96>] do_mpage_readpage+0x0/0x5cc
[ 65.390000] [<000a1848>] __put_page+0x0/0x32
[ 65.390000] [<0010ce8a>] mpage_bio_submit+0x2e/0x3a
[ 65.390000] [<0010d55a>] mpage_readpages+0xf8/0x108
[ 65.390000] [<00080000>] check_ids+0x8/0x64
[ 65.390000] [<00433256>] radix_tree_lookup+0x0/0x1a
[ 65.390000] [<0000bd6e>] rtc_ioctl+0x10c/0x2ae
[ 65.390000] [<00010100>] sixty_four+0x2/0x10
[ 65.390000] [<00001000>] kernel_pg_dir+0x0/0x1000
[ 65.390000] [<00107370>] blkdev_get_block+0x0/0x30
[ 65.390000] [<000a0eb4>] read_pages+0x3c/0xe6
[ 65.390000] [<00107370>] blkdev_get_block+0x0/0x30
[ 65.390000] [<0003ffff>] _sched_setscheduler+0x47/0x7e
[ 65.390000] [<00433256>] radix_tree_lookup+0x0/0x1a
[ 65.390000] [<0009cd42>] __alloc_pages_nodemask+0x0/0x86a
[ 65.390000] [<000a1188>] __do_page_cache_readahead+0x92/0x13e
[ 65.390000] [<000a10f6>] __do_page_cache_readahead+0x0/0x13e
[ 65.390000] [<000a1558>] force_page_cache_readahead+0x94/0xa2
[ 65.390000] [<000a1848>] __put_page+0x0/0x32
[ 65.390000] [<00096316>] unlock_page+0x0/0x2a
[ 65.390000] [<000970f4>] generic_file_buffered_read+0x11e/0x64a
[ 65.390000] [<000986f4>] generic_file_read_iter+0x100/0x132
[ 65.390000] [<000e0246>] __vfs_read+0x116/0x150
[ 65.390000] [<00020000>] _FP_CALL_TOP+0x9a46/0xd512
[ 65.390000] [<000e02dc>] vfs_read+0x5c/0xe4
[ 65.390000] [<000e0766>] ksys_read+0x42/0x8a
[ 65.390000] [<000e07c0>] sys_read+0x12/0x18
[ 65.390000] [<00002934>] syscall+0x8/0xc
[ 65.390000] [<0000c016>] bvme6000_gettimeoffset+0xaa/0xe2
[ 65.390000] Code: 2d20 012a 2839 005f 5124 226b 0014 7001 <b0a9> 0060 6600 0210 4a29 0064 6700 0208 4a8b 6700 0294 2053 2068 0014 2028 002c

Andreas.

--
Andreas Schwab, schwab@xxxxxxxxxxxxxx
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1
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