syzbot

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BUG: KCSAN: data-race in acct_account_cputime / mmap_region

write to 0xffff88803f182640 of 8 bytes by task 3294 on cpu 1:
 vm_stat_account mm/mmap.c:3347 [inline]
 mmap_region+0x5ef/0x1490 mm/mmap.c:1828
 do_mmap+0x77d/0xc90 mm/mmap.c:1545
 vm_mmap_pgoff+0xe5/0x170 mm/util.c:506
 ksys_mmap_pgoff+0xe1/0x380 mm/mmap.c:1596
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88803f182640 of 8 bytes by interrupt on cpu 0:
 __acct_update_integrals kernel/tsacct.c:140 [inline]
 acct_account_cputime+0x15a/0x1a0 kernel/tsacct.c:164
 update_process_times+0x1f/0x140 kernel/time/timer.c:1708
 tick_sched_handle kernel/time/tick-sched.c:176 [inline]
 tick_sched_timer+0x1a2/0x230 kernel/time/tick-sched.c:1328
 __run_hrtimer+0x154/0x4b0 kernel/time/hrtimer.c:1524
 __hrtimer_run_queues kernel/time/hrtimer.c:1588 [inline]
 hrtimer_interrupt+0x37c/0xa40 kernel/time/hrtimer.c:1650
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0xa3/0x280 arch/x86/kernel/apic/apic.c:1097
 asm_call_irq_on_stack+0xf/0x20
 __run_sysvec_on_irqstack arch/x86/include/asm/irq_stack.h:37 [inline]
 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:89 [inline]
 sysvec_apic_timer_interrupt+0x80/0xd0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
 console_unlock+0x8ed/0xab0 arch/x86/include/asm/paravirt.h:770
 vprintk_emit+0x37f/0x4f0 kernel/printk/printk.c:2029
 vprintk_default+0x24/0x30 kernel/printk/printk.c:2047
 vprintk_func+0x13d/0x140 kernel/printk/printk_safe.c:393
 printk+0x62/0x82 kernel/printk/printk.c:2078
 fat_msg+0x80/0xaf fs/fat/misc.c:56
 fat_fill_super+0x2898/0x2a90 fs/fat/inode.c:1891
 vfat_fill_super+0x2c/0x40 fs/fat/namei_vfat.c:1050
 mount_bdev+0x1e8/0x290 fs/super.c:1417
 vfat_mount+0x2d/0x40 fs/fat/namei_vfat.c:1057
 legacy_get_tree+0x70/0xc0 fs/fs_context.c:592
 vfs_get_tree+0x4d/0x1a0 fs/super.c:1547
 do_new_mount fs/namespace.c:2875 [inline]
 path_mount+0x118d/0x1c70 fs/namespace.c:3192
 do_mount fs/namespace.c:3205 [inline]
 __do_sys_mount fs/namespace.c:3413 [inline]
 __se_sys_mount+0x126/0x180 fs/namespace.c:3390
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3390
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3296 Comm: syz-executor.5 Not tainted 5.9.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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