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KCSAN: data-race in loop_configure / shmem_write_begin (4)

Status: auto-obsoleted due to no activity on 2023/09/06 15:54
Subsystems: block
[Documentation on labels]
First crash: 345d, last: 260d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in loop_configure / shmem_write_begin (6) block 1 83d 83d 0/26 auto-obsoleted due to no activity on 2024/03/02 02:49
upstream KCSAN: data-race in loop_configure / shmem_write_begin (2) block 1 548d 548d 0/26 auto-obsoleted due to no activity on 2022/11/22 19:17
upstream KCSAN: data-race in loop_configure / shmem_write_begin (5) block 3 159d 131d 0/26 auto-obsoleted due to no activity on 2023/12/24 00:08
upstream KCSAN: data-race in loop_configure / shmem_write_begin (3) block 3 505d 513d 0/26 auto-obsoleted due to no activity on 2023/01/16 15:13
upstream KCSAN: data-race in loop_configure / shmem_write_begin block 1 1022d 1022d 0/26 auto-closed as invalid on 2021/09/03 06:19

Sample crash report:
==================================================================
BUG: KCSAN: data-race in loop_configure / shmem_write_begin

read-write to 0xffff888153e91a00 of 4 bytes by task 17354 on cpu 0:
 mapping_set_gfp_mask include/linux/pagemap.h:294 [inline]
 loop_configure+0x7c5/0xca0 drivers/block/loop.c:1077
 lo_ioctl+0x682/0x12e0
 blkdev_ioctl+0x375/0x460 block/ioctl.c:621
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xcf/0x140 fs/ioctl.c:856
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888153e91a00 of 4 bytes by task 17349 on cpu 1:
 mapping_gfp_mask include/linux/pagemap.h:278 [inline]
 shmem_get_folio mm/shmem.c:2080 [inline]
 shmem_write_begin+0x8a/0x1d0 mm/shmem.c:2573
 generic_perform_write+0x1cf/0x410 mm/filemap.c:3923
 __generic_file_write_iter+0xa1/0x120 mm/filemap.c:4018
 generic_file_write_iter+0x7d/0x1c0 mm/filemap.c:4044
 do_iter_write+0x4b4/0x7b0 fs/read_write.c:860
 vfs_writev+0x1a8/0x320 fs/read_write.c:933
 do_pwritev fs/read_write.c:1030 [inline]
 __do_sys_pwritev fs/read_write.c:1077 [inline]
 __se_sys_pwritev fs/read_write.c:1072 [inline]
 __x64_sys_pwritev+0x100/0x1c0 fs/read_write.c:1072
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00100cca -> 0x00100c0a

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 17349 Comm: syz-executor.3 Not tainted 6.5.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
==================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/02 15:44 upstream 5d0c230f1de8 b178af49 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in loop_configure / shmem_write_begin
2023/07/10 00:57 upstream 06c2afb862f9 668cb1fa .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in loop_configure / shmem_write_begin
2023/06/28 09:28 upstream 04fc8904d5d1 4cd5bb25 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in loop_configure / shmem_write_begin
2023/05/31 10:05 upstream afead42fdfca 09898419 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in loop_configure / shmem_write_begin
2023/05/10 02:04 upstream 1dc3731daf1f 30aa2a7e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in loop_configure / shmem_write_begin
* Struck through repros no longer work on HEAD.