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KCSAN: data-race in hrtimer_interrupt / print_tickdevice (8)

Status: auto-obsoleted due to no activity on 2023/01/03 04:47
First crash: 138d, last: 115d
similar bugs (7):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in hrtimer_interrupt / print_tickdevice (6) 5 243d 267d 0/24 auto-closed as invalid on 2022/08/27 09:49
upstream KCSAN: data-race in hrtimer_interrupt / print_tickdevice (4) 14 379d 544d 0/24 auto-closed as invalid on 2022/04/13 14:16
upstream KCSAN: data-race in hrtimer_interrupt / print_tickdevice (2) 3 680d 684d 0/24 auto-closed as invalid on 2021/06/16 18:46
upstream KCSAN: data-race in hrtimer_interrupt / print_tickdevice (5) 2 317d 317d 0/24 auto-closed as invalid on 2022/06/15 02:31
upstream KCSAN: data-race in hrtimer_interrupt / print_tickdevice (7) 1 187d 187d 0/24 auto-obsoleted due to no activity on 2022/10/22 07:07
upstream KCSAN: data-race in hrtimer_interrupt / print_tickdevice (3) 2 594d 629d 0/24 auto-closed as invalid on 2021/09/10 15:52
upstream KCSAN: data-race in hrtimer_interrupt / print_tickdevice 1 796d 796d 0/24 auto-closed as invalid on 2021/02/20 21:54

Sample crash report:
==================================================================
BUG: KCSAN: data-race in hrtimer_interrupt / print_tickdevice

write to 0xffff888237d1aed8 of 8 bytes by interrupt on cpu 1:
 hrtimer_interrupt+0xa7/0xa70 kernel/time/hrtimer.c:1790
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline]
 __sysvec_apic_timer_interrupt+0xa3/0x250 arch/x86/kernel/apic/apic.c:1113
 sysvec_apic_timer_interrupt+0x88/0xb0 arch/x86/kernel/apic/apic.c:1107
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
 is_continuation drivers/tty/n_tty.c:402 [inline]
 do_output_char+0x1df/0x4d0 drivers/tty/n_tty.c:475
 process_output drivers/tty/n_tty.c:506 [inline]
 n_tty_write+0x884/0xb10 drivers/tty/n_tty.c:2362
 do_tty_write drivers/tty/tty_io.c:1018 [inline]
 file_tty_write+0x3b8/0x620 drivers/tty/tty_io.c:1089
 tty_write+0x24/0x30 drivers/tty/tty_io.c:1110
 do_iter_write+0x494/0x750 fs/read_write.c:861
 vfs_iter_write+0x4c/0x70 fs/read_write.c:902
 iter_file_splice_write+0x44a/0x7c0 fs/splice.c:686
 do_splice_from fs/splice.c:764 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:931
 splice_direct_to_actor+0x305/0x620 fs/splice.c:886
 do_splice_direct+0xfb/0x180 fs/splice.c:974
 do_sendfile+0x3bf/0x910 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1309
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888237d1aed8 of 8 bytes by task 31879 on cpu 0:
 print_tickdevice+0x158/0x370 kernel/time/timer_list.c:204
 timer_list_show+0x74/0x180 kernel/time/timer_list.c:296
 seq_read_iter+0x676/0x8e0 fs/seq_file.c:272
 proc_reg_read_iter+0xfa/0x170 fs/proc/inode.c:305
 call_read_iter include/linux/fs.h:2193 [inline]
 generic_file_splice_read+0xde/0x2b0 fs/splice.c:309
 do_splice_to fs/splice.c:793 [inline]
 splice_direct_to_actor+0x26c/0x620 fs/splice.c:865
 do_splice_direct+0xfb/0x180 fs/splice.c:974
 do_sendfile+0x3bf/0x910 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1309
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000011998134268 -> 0x000001199813dea8

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 31879 Comm: syz-executor.3 Not tainted 6.1.0-rc7-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
==================================================================

Crashes (3):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci2-upstream-kcsan-gce 2022/11/29 04:11 upstream b7b275e60bcd ca9683b8 .config console log report info [disk image] [vmlinux] [kernel image] KCSAN: data-race in hrtimer_interrupt / print_tickdevice
ci2-upstream-kcsan-gce 2022/11/20 21:46 upstream 77c51ba552a1 5bb70014 .config console log report info [disk image] [vmlinux] [kernel image] KCSAN: data-race in hrtimer_interrupt / print_tickdevice
ci2-upstream-kcsan-gce 2022/11/05 15:59 upstream b208b9fbbcba 6d752409 .config console log report info [disk image] [vmlinux] [kernel image] KCSAN: data-race in hrtimer_interrupt / print_tickdevice
* Struck through repros no longer work on HEAD.