ci2 starts bisection 2024-08-10 04:08:55.372587286 +0000 UTC m=+97.949297555 bisecting cause commit starting from ee9a43b7cfe2d8a3520335fea7d8ce71b8cabd9d building syzkaller on a83d9288459602ce6ab098f191eb2c7a923128c5 ensuring issue is reproducible on original commit ee9a43b7cfe2d8a3520335fea7d8ce71b8cabd9d testing commit ee9a43b7cfe2d8a3520335fea7d8ce71b8cabd9d gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 4966f1ad28afeb94fd9d5efcba2a98a853e0189bf630c5dff675984014b2a1d6 all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] check whether we can drop unnecessary instrumentation disabling configs for [LOCKDEP ATOMIC_SLEEP HANG LEAK UBSAN BUG KASAN], they are not needed testing commit ee9a43b7cfe2d8a3520335fea7d8ce71b8cabd9d gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: dc3e1a26cc59b043781713f3f246b5233b9771faccc173fa2981128ea259bda5 all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] the bug reproduces without the instrumentation disabling configs for [ATOMIC_SLEEP HANG LEAK UBSAN BUG KASAN LOCKDEP], they are not needed kconfig minimization: base=3993 full=8129 leaves diff=2115 split chunks (needed=false): <2115> split chunk #0 of len 2115 into 5 parts testing without sub-chunk 1/5 disabling configs for [LEAK UBSAN BUG KASAN LOCKDEP ATOMIC_SLEEP HANG], they are not needed testing commit ee9a43b7cfe2d8a3520335fea7d8ce71b8cabd9d gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 2a88a9c9745429a9c40bc5876f6d70075fc1a9925b8553cbcaef61c1c2b9f6ed all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] the chunk can be dropped testing without sub-chunk 2/5 disabling configs for [KASAN LOCKDEP ATOMIC_SLEEP HANG LEAK UBSAN BUG], they are not needed testing commit ee9a43b7cfe2d8a3520335fea7d8ce71b8cabd9d gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 4f3ccbb14941a2e215302260493e89518ed55f47f6a64c4d21d82f3750ce2e3c all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] the chunk can be dropped testing without sub-chunk 3/5 disabling configs for [LOCKDEP ATOMIC_SLEEP HANG LEAK UBSAN BUG KASAN], they are not needed testing commit ee9a43b7cfe2d8a3520335fea7d8ce71b8cabd9d gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 72328ed3bfc9f7810a4bfb9e3f5e8d8f20003a2349d57dc25d402ba18ea0df6a all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] the chunk can be dropped testing without sub-chunk 4/5 disabling configs for [KASAN LOCKDEP ATOMIC_SLEEP HANG LEAK UBSAN BUG], they are not needed testing commit ee9a43b7cfe2d8a3520335fea7d8ce71b8cabd9d gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: ae7df06497d8f2342f741dc3e0c4bb92ee0ef19a2529b2fe809be414cc2b7fe7 run #0: basic kernel testing failed: failed to copy syz-execprog to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "IdentitiesOnly=yes" "-o" "BatchMode=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-v" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-execprog" "root@10.128.1.235:./syz-execprog"]: exit status 255 Executing: program /usr/bin/ssh host 10.128.1.235, user root, command sftp OpenSSH_9.2p1 Debian-2+deb12u2, OpenSSL 3.0.11 19 Sep 2023 debug1: Reading configuration data /dev/null debug1: Connecting to 10.128.1.235 [10.128.1.235] port 22. debug1: connect to address 10.128.1.235 port 22: Connection timed out ssh: connect to host 10.128.1.235 port 22: Connection timed out scp: Connection closed run #1: basic kernel testing failed: failed to copy syz-execprog to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "IdentitiesOnly=yes" "-o" "BatchMode=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-v" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-execprog" "root@10.128.0.180:./syz-execprog"]: exit status 255 Executing: program /usr/bin/ssh host 10.128.0.180, user root, command sftp OpenSSH_9.2p1 Debian-2+deb12u2, OpenSSL 3.0.11 19 Sep 2023 debug1: Reading configuration data /dev/null debug1: Connecting to 10.128.0.180 [10.128.0.180] port 22. debug1: connect to address 10.128.0.180 port 22: Connection timed out ssh: connect to host 10.128.0.180 port 22: Connection timed out scp: Connection closed run #2: crashed: divide error in ext4_mb_regular_allocator run #3: crashed: divide error in ext4_mb_regular_allocator run #4: crashed: divide error in ext4_mb_regular_allocator run #5: crashed: divide error in ext4_mb_regular_allocator run #6: crashed: divide error in ext4_mb_regular_allocator run #7: crashed: divide error in ext4_mb_regular_allocator run #8: crashed: divide error in ext4_mb_regular_allocator run #9: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] the chunk can be dropped testing without sub-chunk 5/5 disabling configs for [KASAN LOCKDEP ATOMIC_SLEEP HANG LEAK UBSAN BUG], they are not needed testing commit ee9a43b7cfe2d8a3520335fea7d8ce71b8cabd9d gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 1c447b80237ff2e96313dee95e681cbfb1b771f67b5b1fe50da59ee567efc4bc run #0: basic kernel testing failed: lost connection to test machine run #1: basic kernel testing failed: lost connection to test machine run #2: crashed: divide error in ext4_mb_regular_allocator run #3: crashed: divide error in ext4_mb_regular_allocator run #4: crashed: divide error in ext4_mb_regular_allocator run #5: crashed: divide error in ext4_mb_regular_allocator run #6: crashed: divide error in ext4_mb_regular_allocator run #7: crashed: divide error in ext4_mb_regular_allocator run #8: crashed: divide error in ext4_mb_regular_allocator run #9: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] the chunk can be dropped disabling configs for [HANG LEAK UBSAN BUG KASAN LOCKDEP ATOMIC_SLEEP], they are not needed picked [v6.10 v6.9 v6.8 v6.6 v6.4 v6.2 v6.0 v5.18 v5.15 v5.12 v5.9 v5.6 v5.3 v5.0 v4.19] out of 33 release tags testing release v6.10 testing commit 0c3836482481200ead7b416ca80c68a29cfdaabd gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: c166ed87cb7d80d6dcb45a75c31cfcce152e6b27c28d0a1f627deb78d27184dc all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] testing release v6.9 testing commit a38297e3fb012ddfa7ce0321a7e5a8daeb1872b6 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: dab9076d414b32e0fa33a3cce29e129d2f7d3143373947da17a9920f34f38154 all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] testing release v6.8 testing commit e8f897f4afef0031fe618a8e94127a0934896aba gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 8cff3a53eb503f48c6093da5ac25b4901bac3bd20c088a55c23bf09ae544f638 all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] testing release v6.6 testing commit ffc253263a1375a65fa6c9f62a893e9767fbebfa gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 7c9107ee74676ffc5fb042db554677e019bc1c944dcfe5bf0500e355b72da935 all runs: OK false negative chance: 0.000 # git bisect start e8f897f4afef0031fe618a8e94127a0934896aba ffc253263a1375a65fa6c9f62a893e9767fbebfa Bisecting: 17028 revisions left to test after this (roughly 14 steps) [cae0de45c8fd62612e1ee429134fd82c2c0e335e] Merge branch 'net-phylink-improve-phy-validation' testing commit cae0de45c8fd62612e1ee429134fd82c2c0e335e gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 755ff711062728b815f92fd56ccb1a9e2523c8ca90396b3b323e1b3f52d2249a all runs: OK false negative chance: 0.000 # git bisect good cae0de45c8fd62612e1ee429134fd82c2c0e335e Bisecting: 9372 revisions left to test after this (roughly 13 steps) [ba5afb9a84df2e6b26a1b6389b98849cd16ea757] fs: rework listmount() implementation testing commit ba5afb9a84df2e6b26a1b6389b98849cd16ea757 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: e8108e4658dc5d6e0265f1faa4ad817a72374cf6178417847379d37b2e96d1c9 all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] # git bisect bad ba5afb9a84df2e6b26a1b6389b98849cd16ea757 Bisecting: 3829 revisions left to test after this (roughly 12 steps) [49f4810356f7d4294ad63dc70fe3c65ca3b8ada9] Merge tag 'nfsd-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux testing commit 49f4810356f7d4294ad63dc70fe3c65ca3b8ada9 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: de997dcee45253de3a26e61f24acc523a1842dee88e05fe80f7c30b8031520a3 all runs: OK false negative chance: 0.000 # git bisect good 49f4810356f7d4294ad63dc70fe3c65ca3b8ada9 Bisecting: 1636 revisions left to test after this (roughly 11 steps) [3e7aeb78ab01c2c2f0e1f784e5ddec88fcd3d106] Merge tag 'net-next-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next testing commit 3e7aeb78ab01c2c2f0e1f784e5ddec88fcd3d106 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: a7926ddb26183cc29a6ac56d63c0e217335df1dbc8277b7e49e05c5533784c6a all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] # git bisect bad 3e7aeb78ab01c2c2f0e1f784e5ddec88fcd3d106 Bisecting: 1096 revisions left to test after this (roughly 10 steps) [f6476dedf08ded43bb9fb98ae634c2a1c56fdc06] selftests/net: convert netns-name.sh to run it in unique namespace testing commit f6476dedf08ded43bb9fb98ae634c2a1c56fdc06 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 24ba489a308d1cdcd0591f2f921837a063fe8b022ba723cd0dc37909d5149a8b all runs: OK false negative chance: 0.000 # git bisect good f6476dedf08ded43bb9fb98ae634c2a1c56fdc06 Bisecting: 526 revisions left to test after this (roughly 9 steps) [78273df7f646f8daf2604ec714bea0897cd03aae] Merge tag 'header_cleanup-2024-01-10' of https://evilpiepirate.org/git/bcachefs testing commit 78273df7f646f8daf2604ec714bea0897cd03aae gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 0b3c98e25af43ec9b29bbf00f8db06cfa004562fe22ea04c3622d263b75a85d9 all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] # git bisect bad 78273df7f646f8daf2604ec714bea0897cd03aae Bisecting: 278 revisions left to test after this (roughly 8 steps) [84e9a2d5517bf62edda74f382757aa173b8e45fd] Merge tag 'v6.8-rc-part1-smb-client' of git://git.samba.org/sfrench/cifs-2.6 testing commit 84e9a2d5517bf62edda74f382757aa173b8e45fd gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: c00d4212511b3219bbebb59d1069659336133b7257d3da1d5e15b5d6320a2fbd all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] # git bisect bad 84e9a2d5517bf62edda74f382757aa173b8e45fd Bisecting: 145 revisions left to test after this (roughly 7 steps) [e9b21862587043e2e79ce114b15a578a09106e9e] crypto: sun8i-ce - Use helper to set reqsize testing commit e9b21862587043e2e79ce114b15a578a09106e9e gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 46005f009985655506685f4e2af3d8b40e690adbfd8dd199c879dcbf46e23086 all runs: OK false negative chance: 0.000 # git bisect good e9b21862587043e2e79ce114b15a578a09106e9e Bisecting: 63 revisions left to test after this (roughly 6 steps) [0cb552aa97843f24549ce808883494138471c16b] Merge tag 'v6.8-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 testing commit 0cb552aa97843f24549ce808883494138471c16b gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 5ad4d1056644318a92622732cdd676607d781f000064027babf5a95955f3f44e all runs: OK false negative chance: 0.000 # git bisect good 0cb552aa97843f24549ce808883494138471c16b Bisecting: 40 revisions left to test after this (roughly 5 steps) [0d19d9e14687ff6f43d6c4806ace9ff682d7703f] Merge tag 'ext4_for_linus-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 testing commit 0d19d9e14687ff6f43d6c4806ace9ff682d7703f gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 3bcdf2284fe333a3ebab9516205803ca8409905ce894249cfa2b78aaf6bf3865 all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] # git bisect bad 0d19d9e14687ff6f43d6c4806ace9ff682d7703f Bisecting: 11 revisions left to test after this (roughly 4 steps) [62ec1707cb071c95706d1bab85fbee8d5a3d2f24] jbd2: replace journal state flag by checking errseq testing commit 62ec1707cb071c95706d1bab85fbee8d5a3d2f24 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 61ba23a24817f0a4f928b4f991100bce7c1d596e9a03ac165cf0fdb87b198df6 all runs: OK false negative chance: 0.000 # git bisect good 62ec1707cb071c95706d1bab85fbee8d5a3d2f24 Bisecting: 5 revisions left to test after this (roughly 3 steps) [1f6bc02f18489b9c9ea39b068d0695fb0e4567e9] ext4: fallback to complex scan if aligned scan doesn't work testing commit 1f6bc02f18489b9c9ea39b068d0695fb0e4567e9 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: e0040e72c20d2e60af49a0c9be4bd0013476045bbe141f5229cb002250eb0846 all runs: crashed: divide error in ext4_mb_regular_allocator representative crash: divide error in ext4_mb_regular_allocator, types: [UNKNOWN] # git bisect bad 1f6bc02f18489b9c9ea39b068d0695fb0e4567e9 Bisecting: 2 revisions left to test after this (roughly 2 steps) [ada3fb86a3f3aea40903d5ad9aeec708dc049b8b] ext4: move ext4_check_bdev_write_error() into nojournal mode testing commit ada3fb86a3f3aea40903d5ad9aeec708dc049b8b gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: ba04a77688bd129761cc8caa3113c2cb62c9a414a1cdb577aadbb904b3adc98e all runs: OK false negative chance: 0.000 # git bisect good ada3fb86a3f3aea40903d5ad9aeec708dc049b8b Bisecting: 0 revisions left to test after this (roughly 1 step) [4d5cdd757d0c74924b629559fccb68d8803ce995] ext4: convert ext4_da_do_write_end() to take a folio testing commit 4d5cdd757d0c74924b629559fccb68d8803ce995 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 92ac78d9879785869dafa505d4982ac4cd56f88dbcae34e08495f23858a7b295 all runs: OK false negative chance: 0.000 # git bisect good 4d5cdd757d0c74924b629559fccb68d8803ce995 1f6bc02f18489b9c9ea39b068d0695fb0e4567e9 is the first bad commit commit 1f6bc02f18489b9c9ea39b068d0695fb0e4567e9 Author: Ojaswin Mujoo Date: Fri Dec 15 16:49:50 2023 +0530 ext4: fallback to complex scan if aligned scan doesn't work Currently in case the goal length is a multiple of stripe size we use ext4_mb_scan_aligned() to find the stripe size aligned physical blocks. In case we are not able to find any, we again go back to calling ext4_mb_choose_next_group() to search for a different suitable block group. However, since the linear search always begins from the start, most of the times we end up with the same BG and the cycle continues. With large fliesystems, the CPU can be stuck in this loop for hours which can slow down the whole system. Hence, until we figure out a better way to continue the search (rather than starting from beginning) in ext4_mb_choose_next_group(), lets just fallback to ext4_mb_complex_scan_group() in case aligned scan fails, as it is much more likely to find the needed blocks. Signed-off-by: Ojaswin Mujoo Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/ee033f6dfa0a7f2934437008a909c3788233950f.1702455010.git.ojaswin@linux.ibm.com Signed-off-by: Theodore Ts'o fs/ext4/mballoc.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) accumulated error probability: 0.00 culprit signature: e0040e72c20d2e60af49a0c9be4bd0013476045bbe141f5229cb002250eb0846 parent signature: 92ac78d9879785869dafa505d4982ac4cd56f88dbcae34e08495f23858a7b295 revisions tested: 25, total time: 6h16m27.107640684s (build: 1h45m23.496900574s, test: 3h12m14.079878459s) first bad commit: 1f6bc02f18489b9c9ea39b068d0695fb0e4567e9 ext4: fallback to complex scan if aligned scan doesn't work recipients (to): ["jack@suse.cz" "ojaswin@linux.ibm.com" "tytso@mit.edu"] recipients (cc): [] crash: divide error in ext4_mb_regular_allocator loop0: detected capacity change from 0 to 1024 EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. EXT4-fs: Ignoring removed oldalloc option EXT4-fs (loop0): re-mounted 00000000-0000-0000-0000-000000000000 r/w. Quota mode: none. divide error: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 2791 Comm: syz.0.15 Not tainted 6.7.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:ext4_mb_regular_allocator+0x586/0xef0 fs/ext4/mballoc.c:2894 Code: ed 0f 84 87 00 00 00 48 8b 44 24 30 48 8b b0 80 05 00 00 48 85 f6 74 31 49 63 46 2c 48 8b 4c 24 30 0f b6 49 54 48 d3 ee 31 d2 <48> f7 f6 83 7c 24 5c fe 72 15 48 85 d2 75 10 4c 89 f7 48 8d b4 24 RSP: 0018:ffffc90001f435c8 EFLAGS: 00010246 RAX: 0000000000000001 RBX: ffff888101f2b000 RCX: 0000000000000004 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff824081f3 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88810628e000 R13: 0000000000000003 R14: ffff888112987000 R15: 0000000000000000 FS: 00007f401c2526c0(0000) GS:ffff888237c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f401c9550c0 CR3: 000000010f6a2000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ext4_mb_new_blocks+0x411/0xec0 fs/ext4/mballoc.c:6190 ext4_ext_map_blocks+0x90c/0x1b50 fs/ext4/extents.c:4285 ext4_map_blocks+0x2e4/0x600 fs/ext4/inode.c:621 _ext4_get_block+0x8b/0x150 fs/ext4/inode.c:763 ext4_get_block_unwritten+0x12/0x40 fs/ext4/inode.c:796 __block_write_begin_int+0x184/0x800 fs/buffer.c:2119 ext4_try_to_write_inline_data+0x227/0x620 fs/ext4/inline.c:740 ext4_write_begin+0xa5/0x600 fs/ext4/inode.c:1141 ext4_da_write_begin+0xcd/0x2f0 fs/ext4/inode.c:2875 generic_perform_write+0xa9/0x250 mm/filemap.c:3918 ext4_buffered_write_iter+0xc5/0x150 fs/ext4/file.c:299 ext4_file_write_iter+0x334/0x740 do_iter_write+0x1ef/0x2f0 fs/read_write.c:860 vfs_writev+0x1ba/0x2b0 fs/read_write.c:933 do_pwritev fs/read_write.c:1030 [inline] __do_sys_pwritev2 fs/read_write.c:1089 [inline] __se_sys_pwritev2+0xa8/0x110 fs/read_write.c:1080 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4d/0xf0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f401c7ca9f9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f401c252038 EFLAGS: 00000246 ORIG_RAX: 0000000000000148 RAX: ffffffffffffffda RBX: 00007f401c958f80 RCX: 00007f401c7ca9f9 RDX: 000000000000000f RSI: 00000000200002c0 RDI: 0000000000000004 RBP: 00007f401c8388ee R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000a12 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f401c958f80 R15: 00007ffdf6f91108 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:ext4_mb_regular_allocator+0x586/0xef0 fs/ext4/mballoc.c:2894 Code: ed 0f 84 87 00 00 00 48 8b 44 24 30 48 8b b0 80 05 00 00 48 85 f6 74 31 49 63 46 2c 48 8b 4c 24 30 0f b6 49 54 48 d3 ee 31 d2 <48> f7 f6 83 7c 24 5c fe 72 15 48 85 d2 75 10 4c 89 f7 48 8d b4 24 RSP: 0018:ffffc90001f435c8 EFLAGS: 00010246 RAX: 0000000000000001 RBX: ffff888101f2b000 RCX: 0000000000000004 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff824081f3 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88810628e000 R13: 0000000000000003 R14: ffff888112987000 R15: 0000000000000000 FS: 00007f401c2526c0(0000) GS:ffff888237c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f401c9550c0 CR3: 000000010f6a2000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: ed in (%dx),%eax 1: 0f 84 87 00 00 00 je 0x8e 7: 48 8b 44 24 30 mov 0x30(%rsp),%rax c: 48 8b b0 80 05 00 00 mov 0x580(%rax),%rsi 13: 48 85 f6 test %rsi,%rsi 16: 74 31 je 0x49 18: 49 63 46 2c movslq 0x2c(%r14),%rax 1c: 48 8b 4c 24 30 mov 0x30(%rsp),%rcx 21: 0f b6 49 54 movzbl 0x54(%rcx),%ecx 25: 48 d3 ee shr %cl,%rsi 28: 31 d2 xor %edx,%edx * 2a: 48 f7 f6 div %rsi <-- trapping instruction 2d: 83 7c 24 5c fe cmpl $0xfffffffe,0x5c(%rsp) 32: 72 15 jb 0x49 34: 48 85 d2 test %rdx,%rdx 37: 75 10 jne 0x49 39: 4c 89 f7 mov %r14,%rdi 3c: 48 rex.W 3d: 8d .byte 0x8d 3e: b4 24 mov $0x24,%ah