From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f199.google.com (mail-oi1-f199.google.com [209.85.167.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9A9ED327C0D for ; Mon, 23 Feb 2026 18:32:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771871557; cv=none; b=DcTSys7sjqAvXgqCdzqMpEpW3NvB7DoFrB+gmsWmncRL4NpSo+YzxVaQE9RRBCytwK7RWZ/CWCQxvMx/75AQNcEKZNtu9gfDO7i8bNJ3YTgLu14AGiPGomC/IFTc7kw8Yu3nE/21vpYxJDrE6n+AZB/UYnHrWeNaObhB8F4flfM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771871557; c=relaxed/simple; bh=u0c+T4svtDvU/xPwGG9WXLOaDDpokIbKCo6otT/sycM=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=pZTA56SIDIlUPhgjRVSeQaVH5GCv1buWY5pVLAnaxYHNagOgDffB5Ku3MGH1MpKUTyyQmWhctVVG2LaNQLYdhG8OwGl8t3DwQz5vZTgQzZ6Aaj2bQ6+rPpXCgaP/jmI0xsJKorQB5IqfVGKj7BmBXSPQUdhIJnEBOYfNDgb8EPI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.167.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oi1-f199.google.com with SMTP id 5614622812f47-4639eb7bd4cso17881458b6e.2 for ; Mon, 23 Feb 2026 10:32:35 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1771871554; x=1772476354; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=7QMuhMBNjRk6WcObcYhdE75jwu9GjlU0BlV6mMFMPZ8=; b=hCS9RTEd1q7XJBouUL6if+MkByh0YLskMv/u5PN1cUjznkmVhZk5obfOR0o9R37ARY UW3uRvBZL9xVNi0lCevhi1S70ZoVh8rVKGb9O5fbzB5/EMigKDCbqoHICaNcZJiKM3by ofDblKdYFvkcF0YBI79J81Ju25YBKDrs8mb95wb1dC180okmub6swFJe+b4ln7/o0Nqe taO/+/y956tD+aoks/L1chd7LiNmaPOkI+z9DzuAEJ6vZAg8y+bffLfj8bSOeBqUYhp4 qvG3yKoqvovWj4pKBzFytnHITFg4VkmGPv/NmJ8jU4GKyZDkpbtixqWhLPK0Hx9PFNyz H9yQ== X-Forwarded-Encrypted: i=1; AJvYcCXKFh8GQGuR1I7YYgpq3nmTvEPd/+FNH/nxqiVIbrOjNoUQTsZ+YstDn/dhQ9nUNqkawFX0ns5LErjA6s8=@vger.kernel.org X-Gm-Message-State: AOJu0YzRZYvKp7a2I22u+3T5BEZU6/Sfvr2uPTcraH+fmhrAG8G5YKit GTKvGDB1V7WM1fWS1ctK/TTg2ZJdAyt96uqdY2NWfIMV1hXYvHOzJ9ePeVbTVHy6vg5jxBxo1WS CJDbmCKVl5ehU/+k2hE/BqRKDSEhcwALLjVhmSkERqejO1A7F34K11un7nlM= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:1404:b0:45e:f8af:e2f with SMTP id 5614622812f47-4644618c12dmr5948855b6e.15.1771871554530; Mon, 23 Feb 2026 10:32:34 -0800 (PST) Date: Mon, 23 Feb 2026 10:32:34 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <699c9d42.a00a0220.121a60.00ee.GAE@google.com> Subject: [syzbot] [mm?] WARNING in __put_task_struct (6) From: syzbot To: Liam.Howlett@oracle.com, akpm@linux-foundation.org, bsegall@google.com, david@kernel.org, dietmar.eggemann@arm.com, juri.lelli@redhat.com, kees@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-usb@vger.kernel.org, lorenzo.stoakes@oracle.com, mgorman@suse.de, mhocko@suse.com, mingo@redhat.com, peterz@infradead.org, rostedt@goodmis.org, rppt@kernel.org, surenb@google.com, syzkaller-bugs@googlegroups.com, vbabka@suse.cz, vincent.guittot@linaro.org, vschneid@redhat.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 2b7a25df823d Merge tag 'mm-nonmm-stable-2026-02-18-19-56' .. git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing console output: https://syzkaller.appspot.com/x/log.txt?x=14573b3a580000 kernel config: https://syzkaller.appspot.com/x/.config?x=1ff39736314a9939 dashboard link: https://syzkaller.appspot.com/bug?extid=c978a74d4872e06c4928 compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/10a06102f92f/disk-2b7a25df.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/cb322de10b94/vmlinux-2b7a25df.xz kernel image: https://storage.googleapis.com/syzbot-assets/7a3e5e026b94/bzImage-2b7a25df.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+c978a74d4872e06c4928@syzkaller.appspotmail.com ------------[ cut here ]------------ refcount_read(&tsk->usage) WARNING: kernel/fork.c:779 at __put_task_struct+0x33c/0x400 kernel/fork.c:779, CPU#1: kworker/1:6/5227 Modules linked in: CPU: 1 UID: 0 PID: 5227 Comm: kworker/1:6 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: usb_hub_wq hub_event RIP: 0010:__put_task_struct+0x33c/0x400 kernel/fork.c:779 Code: 4c 89 e6 e8 b6 7e 98 00 e9 f2 fe ff ff e8 fc 7a 3d 00 be 03 00 00 00 4c 89 e7 e8 1f a0 57 01 e9 db fe ff ff e8 e5 7a 3d 00 90 <0f> 0b 90 e8 dc 7a 3d 00 65 48 3b 1d 4c 94 80 0b 0f 85 64 fd ff ff RSP: 0018:ffffc900001a8e00 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88811283d700 RCX: ffffffff8174391b RDX: ffff88811956ba00 RSI: ffffffff81743bbb RDI: ffff88811956ba00 RBP: 00000000c0000000 R08: 0000000000000005 R09: 0000000000000000 R10: 00000000c0000000 R11: 0000000000000000 R12: dffffc0000000000 R13: ffff88811956ba00 R14: ffffffff81984efd R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8882687d3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe6af2e9d40 CR3: 00000001195d8000 CR4: 00000000003506f0 Call Trace: rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2869 handle_softirqs+0x1de/0x9d0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_flush_one_record+0xac3/0xe50 kernel/printk/printk.c:3270 Code: 00 e8 51 5a 28 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 5f 62 20 00 48 85 ed 0f 85 d7 01 00 00 e8 71 67 20 00 fb 4c 89 e8 <48> c1 e8 03 42 80 3c 38 00 0f 85 64 03 00 00 48 8b 0c 24 48 8b 6b RSP: 0018:ffffc9000362ea68 EFLAGS: 00000283 RAX: ffffffff89c75f58 RBX: ffffffff89c75f00 RCX: ffffc90012887000 RDX: 0000000000100000 RSI: ffffffff81914f2f RDI: ffff88811956ba00 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000012857 R13: ffffffff89c75f58 R14: ffffc9000362eae8 R15: dffffc0000000000 console_flush_all kernel/printk/printk.c:3343 [inline] __console_flush_and_unlock kernel/printk/printk.c:3373 [inline] console_unlock+0x103/0x260 kernel/printk/printk.c:3413 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479 __warn_printf lib/bug.c:190 [inline] __report_bug.cold+0x7b/0x137 lib/bug.c:244 report_bug_entry+0xe1/0x290 lib/bug.c:269 handle_bug+0x1c9/0x2a0 arch/x86/kernel/traps.c:430 exc_invalid_op+0x17/0x50 arch/x86/kernel/traps.c:489 asm_exc_invalid_op+0x1a/0x20 arch/x86/include/asm/idtentry.h:616 RIP: 0010:refcount_warn_saturate+0x111/0x130 lib/refcount.c:25 Code: cc e8 e3 d9 e5 fe 48 8d 3d 4c 70 28 08 67 48 0f b9 3a e8 d2 d9 e5 fe 5b 5d e9 cb 6d 9f 04 e8 c6 d9 e5 fe 48 8d 3d 3f 70 28 08 <67> 48 0f b9 3a e8 b5 d9 e5 fe 5b 5d c3 cc cc cc cc 48 89 df e8 46 RSP: 0018:ffffc9000362ef30 EFLAGS: 00010283 RAX: 00000000000428c1 RBX: ffff88811283d728 RCX: ffffc90012887000 RDX: 0000000000100000 RSI: ffffffff82cbdcda RDI: ffffffff8af44d20 RBP: 0000000000000002 R08: 0000000000000005 R09: 0000000000000004 R10: 0000000000000002 R11: ffff8881f5739708 R12: ffff88810cf18000 R13: ffff88811283d728 R14: 0000000000000001 R15: 0000000000000001 __refcount_add include/linux/refcount.h:289 [inline] __refcount_inc include/linux/refcount.h:366 [inline] refcount_inc include/linux/refcount.h:383 [inline] get_task_struct include/linux/sched/task.h:116 [inline] kthread_stop+0x602/0x680 kernel/kthread.c:786 rsi_kill_thread drivers/net/wireless/rsi/rsi_common.h:78 [inline] rsi_91x_deinit+0x102/0x1f0 drivers/net/wireless/rsi/rsi_91x_main.c:405 rsi_probe+0xd27/0x1aa0 drivers/net/wireless/rsi/rsi_91x_usb.c:861 usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:583 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:661 __driver_probe_device+0x1de/0x400 drivers/base/dd.c:803 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:833 __device_attach_driver+0x1ff/0x3e0 drivers/base/dd.c:961 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1033 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1088 bus_probe_device+0x64/0x160 drivers/base/bus.c:574 device_add+0x11d9/0x1950 drivers/base/core.c:3689 usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:583 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:661 __driver_probe_device+0x1de/0x400 drivers/base/dd.c:803 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:833 __device_attach_driver+0x1ff/0x3e0 drivers/base/dd.c:961 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1033 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1088 bus_probe_device+0x64/0x160 drivers/base/bus.c:574 device_add+0x11d9/0x1950 drivers/base/core.c:3689 usb_new_device.cold+0x685/0x115c drivers/usb/core/hub.c:2695 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x314d/0x4af0 drivers/usb/core/hub.c:5953 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ---------------- Code disassembly (best guess): 0: 00 e8 add %ch,%al 2: 51 push %rcx 3: 5a pop %rdx 4: 28 00 sub %al,(%rax) 6: 9c pushf 7: 5d pop %rbp 8: 81 e5 00 02 00 00 and $0x200,%ebp e: 31 ff xor %edi,%edi 10: 48 89 ee mov %rbp,%rsi 13: e8 5f 62 20 00 call 0x206277 18: 48 85 ed test %rbp,%rbp 1b: 0f 85 d7 01 00 00 jne 0x1f8 21: e8 71 67 20 00 call 0x206797 26: fb sti 27: 4c 89 e8 mov %r13,%rax * 2a: 48 c1 e8 03 shr $0x3,%rax <-- trapping instruction 2e: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) 33: 0f 85 64 03 00 00 jne 0x39d 39: 48 8b 0c 24 mov (%rsp),%rcx 3d: 48 rex.W 3e: 8b .byte 0x8b 3f: 6b .byte 0x6b --- This report is generated by a bot. 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