./strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ./syz-executor266436607 <...> Warning: Permanently added '10.128.0.136' (ED25519) to the list of known hosts. execve("./syz-executor266436607", ["./syz-executor266436607"], 0x7ffdeb5e50b0 /* 10 vars */) = 0 brk(NULL) = 0x55555dada000 brk(0x55555dadad00) = 0x55555dadad00 arch_prctl(ARCH_SET_FS, 0x55555dada380) = 0 set_tid_address(0x55555dada650) = 5875 set_robust_list(0x55555dada660, 24) = 0 rseq(0x55555dadaca0, 0x20, 0, 0x53053053) = 0 prlimit64(0, RLIMIT_STACK, NULL, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0 readlink("/proc/self/exe", "/root/syz-executor266436607", 4096) = 27 getrandom("\x9c\x11\x8b\xe1\xfa\xba\x8a\x1b", 8, GRND_NONBLOCK) = 8 brk(NULL) = 0x55555dadad00 brk(0x55555dafbd00) = 0x55555dafbd00 brk(0x55555dafc000) = 0x55555dafc000 mprotect(0x7f24e9d61000, 16384, PROT_READ) = 0 mmap(0x1ffff000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x1ffff000 mmap(0x20000000, 16777216, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x20000000 mmap(0x21000000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x21000000 openat(AT_FDCWD, "/dev/loop0", O_RDWR) = 3 ioctl(3, LOOP_CLR_FD) = -1 ENXIO (No such device or address) close(3) = 0 clone(child_stack=NULL, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD./strace-static-x86_64: Process 5876 attached [pid 5876] set_robust_list(0x55555dada660, 24 [pid 5875] <... clone resumed>, child_tidptr=0x55555dada650) = 5876 [pid 5876] <... set_robust_list resumed>) = 0 [pid 5876] prctl(PR_SET_PDEATHSIG, SIGKILL) = 0 [pid 5876] setpgid(0, 0) = 0 [pid 5876] openat(AT_FDCWD, "/proc/self/oom_score_adj", O_WRONLY|O_CLOEXEC) = 3 [pid 5876] write(3, "1000", 4) = 4 [pid 5876] close(3) = 0 [pid 5876] write(1, "executing program\n", 18executing program ) = 18 [pid 5876] memfd_create("syzkaller", 0) = 3 [pid 5876] mmap(NULL, 138412032, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f24e1800000 [pid 5876] write(3, "\xeb\x76\x90\x45\x58\x46\x41\x54\x20\x20\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x80\x00\x00\x00\x08\x00\x00\x00\x88\x00\x00\x00\x0f\x00\x00\x00\x05\x00\x00\x00"..., 131072) = 131072 [pid 5876] munmap(0x7f24e1800000, 138412032) = 0 [pid 5876] openat(AT_FDCWD, "/dev/loop0", O_RDWR) = 4 [pid 5876] ioctl(4, LOOP_SET_FD, 3) = 0 [pid 5876] close(3) = 0 [pid 5876] close(4) = 0 [pid 5876] mkdir("./file2", 0777) = 0 [pid 5876] mount("/dev/loop0", "./file2", "exfat", MS_SYNCHRONOUS|MS_NODIRATIME, "") = 0 [pid 5876] openat(AT_FDCWD, "./file2", O_RDONLY|O_DIRECTORY) = 3 [pid 5876] chdir("./file2") = 0 [pid 5876] openat(AT_FDCWD, "/dev/loop0", O_RDWR) = -1 EBUSY (Device or resource busy) [pid 5876] truncate("./file2", 25600) = 0 [ 414.774777][ T5876] loop0: detected capacity change from 0 to 256 [ 414.809761][ T5876] exFAT-fs (loop0): failed to load upcase table (idx : 0x0000fd4f, chksum : 0x3963664b, utbl_chksum : 0xe619d30d) [pid 5876] openat(AT_FDCWD, "./file2", O_RDONLY|O_EXCL|O_TRUNC [pid 5875] kill(-5876, SIGKILL) = 0 [pid 5875] kill(5876, SIGKILL) = 0 [pid 5875] openat(AT_FDCWD, "/sys/fs/fuse/connections", O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_DIRECTORY) = 3 [pid 5875] newfstatat(3, "", {st_mode=S_IFDIR|0755, st_size=0, ...}, AT_EMPTY_PATH) = 0 [pid 5875] getdents64(3, 0x55555dadb6f0 /* 2 entries */, 32768) = 48 [pid 5875] getdents64(3, 0x55555dadb6f0 /* 0 entries */, 32768) = 0 [pid 5875] close(3) = 0 [ 573.320565][ T30] INFO: task kworker/u8:2:35 blocked for more than 143 seconds. [ 573.328397][ T30] Not tainted 6.12.0-syzkaller-09073-g9f16d5e6f220 #0 [ 573.336409][ T30] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 573.345347][ T30] task:kworker/u8:2 state:D stack:21656 pid:35 tgid:35 ppid:2 flags:0x00004000 [ 573.355805][ T30] Workqueue: writeback wb_workfn (flush-7:0) [ 573.362030][ T30] Call Trace: [ 573.365334][ T30] [ 573.368284][ T30] __schedule+0x17fb/0x4be0 [ 573.373133][ T30] ? __pfx___schedule+0x10/0x10 [ 573.378136][ T30] ? __blk_flush_plug+0x449/0x500 [ 573.383476][ T30] ? __pfx_lock_release+0x10/0x10 [ 573.388562][ T30] ? kthread_data+0x52/0xd0 [ 573.393357][ T30] ? schedule+0x90/0x320 [ 573.397658][ T30] ? wq_worker_sleeping+0x66/0x240 [ 573.403023][ T30] ? schedule+0x90/0x320 [ 573.407307][ T30] schedule+0x14b/0x320 [ 573.411737][ T30] schedule_preempt_disabled+0x13/0x30 [ 573.417229][ T30] __mutex_lock+0x7e7/0xee0 [ 573.421983][ T30] ? __mutex_lock+0x5ef/0xee0 [ 573.426732][ T30] ? exfat_write_inode+0xe5/0x1a0 [ 573.432024][ T30] ? __pfx___mutex_lock+0x10/0x10 [ 573.437098][ T30] ? __writeback_single_inode+0x48f/0x10d0 [ 573.443455][ T30] ? do_raw_spin_unlock+0x13c/0x8b0 [ 573.448717][ T30] exfat_write_inode+0xe5/0x1a0 [ 573.454332][ T30] __writeback_single_inode+0x711/0x10d0 [ 573.460032][ T30] writeback_sb_inodes+0x80c/0x1370 [ 573.465679][ T30] ? mark_lock+0x2ae/0x360 [ 573.470147][ T30] ? __lock_acquire+0x1397/0x2100 [ 573.475470][ T30] ? __pfx_writeback_sb_inodes+0x10/0x10 [ 573.481655][ T30] ? __pfx___up_read+0x10/0x10 [ 573.486473][ T30] ? do_raw_spin_lock+0x14f/0x370 [ 573.492082][ T30] __writeback_inodes_wb+0x11b/0x260 [ 573.497431][ T30] wb_writeback+0x427/0xbc0 [ 573.502424][ T30] ? queue_io+0x311/0x5a0 [ 573.506828][ T30] ? __pfx_wb_writeback+0x10/0x10 [ 573.512433][ T30] wb_workfn+0xc58/0x1090 [ 573.516848][ T30] ? __pfx_wb_workfn+0x10/0x10 [ 573.522084][ T30] ? lockdep_hardirqs_on_prepare+0x43d/0x780 [ 573.528137][ T30] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10 [ 573.534949][ T30] ? process_scheduled_works+0x976/0x1850 [ 573.541001][ T30] process_scheduled_works+0xa63/0x1850 [ 573.546644][ T30] ? __pfx_process_scheduled_works+0x10/0x10 [ 573.553100][ T30] ? assign_work+0x364/0x3d0 [ 573.557744][ T30] worker_thread+0x870/0xd30 [ 573.563463][ T30] ? _raw_spin_unlock_irqrestore+0xdd/0x140 [ 573.569413][ T30] ? __kthread_parkme+0x169/0x1d0 [ 573.575721][ T30] ? __pfx_worker_thread+0x10/0x10 [ 573.581245][ T30] kthread+0x2f0/0x390 [ 573.585364][ T30] ? __pfx_worker_thread+0x10/0x10 [ 573.590917][ T30] ? __pfx_kthread+0x10/0x10 [ 573.595554][ T30] ret_from_fork+0x4b/0x80 [ 573.600858][ T30] ? __pfx_kthread+0x10/0x10 [ 573.605503][ T30] ret_from_fork_asm+0x1a/0x30 [ 573.610340][ T30] [ 573.614111][ T30] [ 573.614111][ T30] Showing all locks held in the system: [ 573.622258][ T30] 1 lock held by khungtaskd/30: [ 573.627139][ T30] #0: ffffffff8e93c520 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 [ 573.637930][ T30] 4 locks held by kworker/u8:2/35: [ 573.643416][ T30] #0: ffff888141a94948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 [ 573.655066][ T30] #1: ffffc90000ab7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 [ 573.667955][ T30] #2: ffff88807b57c0e0 (&type->s_umount_key#43){.+.+}-{4:4}, at: super_trylock_shared+0x22/0xf0 [ 573.679199][ T30] #3: ffff88807b57a0e8 (&sbi->s_lock){+.+.}-{4:4}, at: exfat_write_inode+0xe5/0x1a0 [ 573.689505][ T30] 2 locks held by getty/5602: [ 573.694611][ T30] #0: ffff888030c060a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 [ 573.704887][ T30] #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 [ 573.715374][ T30] 5 locks held by syz-executor266/5876: [ 573.721201][ T30] [ 573.723552][ T30] ============================================= [ 573.723552][ T30] [ 573.732654][ T30] NMI backtrace for cpu 0 [ 573.737012][ T30] CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-syzkaller-09073-g9f16d5e6f220 #0 [ 573.747180][ T30] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 [ 573.757364][ T30] Call Trace: [ 573.760668][ T30] [ 573.763633][ T30] dump_stack_lvl+0x241/0x360 [ 573.768355][ T30] ? __pfx_dump_stack_lvl+0x10/0x10 [ 573.773613][ T30] ? __pfx__printk+0x10/0x10 [ 573.778276][ T30] nmi_cpu_backtrace+0x49c/0x4d0 [ 573.783264][ T30] ? __pfx_nmi_cpu_backtrace+0x10/0x10 [ 573.788776][ T30] ? _printk+0xd5/0x120 [ 573.792974][ T30] ? __pfx__printk+0x10/0x10 [ 573.797601][ T30] ? __wake_up_klogd+0xcc/0x110 [ 573.802500][ T30] ? __pfx__printk+0x10/0x10 [ 573.807133][ T30] ? __rcu_read_unlock+0xa1/0x110 [ 573.812189][ T30] ? __pfx_nmi_raise_cpu_backtrace+0x10/0x10 [ 573.818209][ T30] nmi_trigger_cpumask_backtrace+0x198/0x320 [ 573.824243][ T30] watchdog+0xff4/0x1040 [ 573.828519][ T30] ? watchdog+0x1ea/0x1040 [ 573.832975][ T30] ? __pfx_watchdog+0x10/0x10 [ 573.837680][ T30] kthread+0x2f0/0x390 [ 573.841779][ T30] ? __pfx_watchdog+0x10/0x10 [ 573.846483][ T30] ? __pfx_kthread+0x10/0x10 [ 573.851155][ T30] ret_from_fork+0x4b/0x80 [ 573.855614][ T30] ? __pfx_kthread+0x10/0x10 [ 573.860245][ T30] ret_from_fork_asm+0x1a/0x30 [ 573.865072][ T30] [ 573.868298][ T30] Sending NMI from CPU 0 to CPUs 1: [ 573.873614][ C1] NMI backtrace for cpu 1 [ 573.873630][ C1] CPU: 1 UID: 0 PID: 5876 Comm: syz-executor266 Not tainted 6.12.0-syzkaller-09073-g9f16d5e6f220 #0 [ 573.873650][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 [ 573.873661][ C1] RIP: 0010:check_preemption_disabled+0x60/0x120 [ 573.873693][ C1] Code: 00 48 3b 44 24 08 0f 85 ce 00 00 00 89 d8 48 83 c4 10 5b 41 5c 41 5e 41 5f c3 cc cc cc cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 04 24 00 02 00 00 74 c5 49 89 f6 49 89 ff 65 4c 8b 24 25 80 d4 [ 573.873707][ C1] RSP: 0018:ffffc9000401f028 EFLAGS: 00000046 [ 573.873728][ C1] RAX: 0000000080000000 RBX: 0000000000000001 RCX: ffffffff9a3f1903 [ 573.873741][ C1] RDX: dffffc0000000000 RSI: ffffffff8c0ae5e0 RDI: ffffffff8c6080a0 [ 573.873755][ C1] RBP: ffffc9000401f108 R08: ffffffff901d13b7 R09: 1ffffffff203a276 [ 573.873768][ C1] R10: dffffc0000000000 R11: fffffbfff203a277 R12: ffff8880710b13a0 [ 573.873781][ C1] R13: 0000000000039838 R14: b4c5424000571098 R15: 1ffff92000803e10 [ 573.873794][ C1] FS: 000055555dada380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 [ 573.873809][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 573.873821][ C1] CR2: 00005594e6f498e8 CR3: 0000000072f92000 CR4: 00000000003526f0 [ 573.873836][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 573.873847][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 573.873858][ C1] Call Trace: [ 573.873864][ C1] [ 573.873871][ C1] ? nmi_cpu_backtrace+0x3c2/0x4d0 [ 573.873899][ C1] ? __pfx_lock_acquire+0x10/0x10 [ 573.873919][ C1] ? __pfx_nmi_cpu_backtrace+0x10/0x10 [ 573.873945][ C1] ? nmi_handle+0x2a/0x5a0 [ 573.873972][ C1] ? nmi_cpu_backtrace_handler+0xc/0x20 [ 573.873997][ C1] ? nmi_handle+0x14f/0x5a0 [ 573.874016][ C1] ? nmi_handle+0x2a/0x5a0 [ 573.874035][ C1] ? check_preemption_disabled+0x60/0x120 [ 573.874058][ C1] ? default_do_nmi+0x63/0x160 [ 573.874075][ C1] ? exc_nmi+0x123/0x1f0 [ 573.874090][ C1] ? end_repeat_nmi+0xf/0x53 [ 573.874121][ C1] ? check_preemption_disabled+0x60/0x120 [ 573.874145][ C1] ? check_preemption_disabled+0x60/0x120 [ 573.874170][ C1] ? check_preemption_disabled+0x60/0x120 [ 573.874194][ C1] [ 573.874200][ C1] [ 573.874207][ C1] lockdep_hardirqs_on_prepare+0x1f9/0x780 [ 573.874228][ C1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10 [ 573.874249][ C1] ? rcu_is_watching+0x15/0xb0 [ 573.874272][ C1] trace_hardirqs_on+0x28/0x40 [ 573.874288][ C1] __find_get_block+0x573/0x1150 [ 573.874314][ C1] ? mark_lock+0x9a/0x360 [ 573.874333][ C1] ? __pfx___find_get_block+0x10/0x10 [ 573.874351][ C1] ? __pfx___might_resched+0x10/0x10 [ 573.874376][ C1] ? lockdep_hardirqs_on_prepare+0x43d/0x780 [ 573.874398][ C1] ? fs_reclaim_acquire+0x93/0x130 [ 573.874424][ C1] bdev_getblk+0x33/0x550 [ 573.874447][ C1] __bread_gfp+0x86/0x400 [ 573.874466][ C1] exfat_ent_get+0x14d/0x400 [ 573.874492][ C1] __exfat_free_cluster+0x56f/0x990 [ 573.874521][ C1] ? __pfx___exfat_free_cluster+0x10/0x10 [ 573.874543][ C1] ? kmem_cache_free+0x1a2/0x420 [ 573.874566][ C1] ? do_raw_spin_unlock+0x13c/0x8b0 [ 573.874593][ C1] exfat_free_cluster+0x77/0xd0 [ 573.874617][ C1] __exfat_truncate+0x745/0xa60 [ 573.874647][ C1] ? __pfx___exfat_truncate+0x10/0x10 [ 573.874674][ C1] ? truncate_setsize+0xcf/0xf0 [ 573.874696][ C1] exfat_setattr+0x10fa/0x1a90 [ 573.874723][ C1] ? __pfx_smack_inode_setattr+0x10/0x10 [ 573.874752][ C1] ? __pfx_exfat_setattr+0x10/0x10 [ 573.874775][ C1] ? evm_inode_setattr+0x1b2/0x7d0 [ 573.874805][ C1] ? security_inode_setattr+0xdb/0x350 [ 573.874829][ C1] ? __pfx_exfat_setattr+0x10/0x10 [ 573.874855][ C1] notify_change+0xbca/0xe90 [ 573.874887][ C1] do_truncate+0x220/0x310 [ 573.874914][ C1] ? __pfx_do_truncate+0x10/0x10 [ 573.874947][ C1] path_openat+0x2e1e/0x3590 [ 573.874986][ C1] ? __pfx_path_openat+0x10/0x10 [ 573.875019][ C1] do_filp_open+0x27f/0x4e0 [ 573.875043][ C1] ? __pfx_do_filp_open+0x10/0x10 [ 573.875066][ C1] ? do_raw_spin_lock+0x14f/0x370 [ 573.875109][ C1] do_sys_openat2+0x13e/0x1d0 [ 573.875130][ C1] ? __pfx_do_sys_openat2+0x10/0x10 [ 573.875150][ C1] ? lockdep_hardirqs_on+0x99/0x150 [ 573.875171][ C1] ? _raw_spin_unlock_irq+0x2e/0x50 [ 573.875192][ C1] ? ptrace_notify+0x279/0x380 [ 573.875216][ C1] __x64_sys_openat+0x247/0x2a0 [ 573.875238][ C1] ? __pfx___x64_sys_openat+0x10/0x10 [ 573.875260][ C1] ? do_syscall_64+0x100/0x230 [ 573.875287][ C1] do_syscall_64+0xf3/0x230 [ 573.875313][ C1] ? clear_bhb_loop+0x35/0x90 [ 573.875340][ C1] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 573.875364][ C1] RIP: 0033:0x7f24e9ceca99 [ 573.875390][ C1] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 [ 573.875403][ C1] RSP: 002b:00007ffcb3a6e888 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 [ 573.875421][ C1] RAX: ffffffffffffffda RBX: 0032656c69662f2e RCX: 00007f24e9ceca99 [ 573.875434][ C1] RDX: 0000000000000280 RSI: 0000000020000000 RDI: ffffffffffffff9c [ 573.875446][ C1] RBP: 00007f24e9d615f0 R08: 000055555dadb4c0 R09: 000055555dadb4c0 [ 573.875458][ C1] R10: 0000000000000001 R11: 0000000000000246 R12: 00007ffcb3a6e8b0 [ 573.875469][ C1] R13: 00007ffcb3a6ead8 R14: 431bde82d7b634db R15: 00007f24e9d3503b [ 573.875489][ C1] [ 573.875500][ C1] INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.882 msecs [ 573.875902][ T30] Kernel panic - not syncing: hung_task: blocked tasks [ 574.416848][ T30] CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-syzkaller-09073-g9f16d5e6f220 #0 [ 574.427014][ T30] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 [ 574.437079][ T30] Call Trace: [ 574.440364][ T30] [ 574.443301][ T30] dump_stack_lvl+0x241/0x360 [ 574.447996][ T30] ? __pfx_dump_stack_lvl+0x10/0x10 [ 574.453207][ T30] ? __pfx__printk+0x10/0x10 [ 574.457813][ T30] ? lockdep_hardirqs_on_prepare+0x43d/0x780 [ 574.463808][ T30] ? vscnprintf+0x5d/0x90 [ 574.468157][ T30] panic+0x349/0x880 [ 574.472064][ T30] ? nmi_trigger_cpumask_backtrace+0x244/0x320 [ 574.478231][ T30] ? __pfx_panic+0x10/0x10 [ 574.482662][ T30] ? preempt_schedule_thunk+0x1a/0x30 [ 574.488039][ T30] ? nmi_trigger_cpumask_backtrace+0x244/0x320 [ 574.494218][ T30] ? nmi_trigger_cpumask_backtrace+0x2d4/0x320 [ 574.500390][ T30] ? nmi_trigger_cpumask_backtrace+0x2d9/0x320 [ 574.506564][ T30] watchdog+0x1033/0x1040 [ 574.510903][ T30] ? watchdog+0x1ea/0x1040 [ 574.515331][ T30] ? __pfx_watchdog+0x10/0x10 [ 574.520029][ T30] kthread+0x2f0/0x390 [ 574.524108][ T30] ? __pfx_watchdog+0x10/0x10 [ 574.528788][ T30] ? __pfx_kthread+0x10/0x10 [ 574.533389][ T30] ret_from_fork+0x4b/0x80 [ 574.537807][ T30] ? __pfx_kthread+0x10/0x10 [ 574.542406][ T30] ret_from_fork_asm+0x1a/0x30 [ 574.547196][ T30] [ 574.550652][ T30] Kernel Offset: disabled [ 574.554993][ T30] Rebooting in 86400 seconds..