From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f78.google.com (mail-ot1-f78.google.com [209.85.210.78]) (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 898E3155A5D for ; Wed, 28 Jan 2026 10:40:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.78 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769596830; cv=none; b=ipaXGT98/8y1NsjQ+tWUHQQ1JkGNvUOW63KL4ywKqF8ZSSMwdzCncDV+c9NEhwiM+4mf/WoVXQKr9zGKvblDD7Uh2JO9W7X5hnad9HrcSsmZlwO9/ONEA8E+7lxDCf8bwSen11BbGF189ll7TNTz7XBlCKWCH48gaek77GLhBr4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769596830; c=relaxed/simple; bh=Qqo+yYEriWl7JO4xAVuipbVs8QRMEZtQOsi1HxiDvtQ=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=hTrOwxioEQ7IXYbYVOEUxqibX65IxD3Gb8Inbwe/73QRghx6kcBI6+3543RH5YcYPRwvUyh//1MMZCAHpBRIbK7cP80lN3ucJkyj4YHTgOyqaRxM4uMvuKbYVhmrmYRYuRj6NA0paEIoukbaFBjMiA9fUUff2ia6DfUab8lHEVg= 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=209.85.210.78 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-ot1-f78.google.com with SMTP id 46e09a7af769-7cfd0f67288so15622917a34.3 for ; Wed, 28 Jan 2026 02:40:28 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1769596827; x=1770201627; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=CLXr3Bkp5M2uDrNKrNeuI4+yMF8NaMSvPrd1HvfJ2S4=; b=BX2cklPbuHmMkOK2OT7Mm0tihiBCG6a9i62H8YSSsTlGh5/oB4i6+sIYLxTnxa1tyw oQUWNc/PNYlff0GPhL+ckAEZJh8Unf2yDY8vENdlluYj9ND5nGI74R8VAxG4b6EzIwNI Iv86Dks5lMtoam7AsGjEPPBSt7LoSm2E6UbSZdYxG89L1z9KBal2IwMljmIVjvUOiMSB sWwuKvenjSDq+qFgseE6L114X+R1sVP7TlpSxl6olVeNtkMv3IKVw5MnQdP3EuAwcKJB E6By2niAgfw0QJ5QkI+c13q6m2LHASmTvTaXnegkedmQQx9FVhZPfO8gdWJ+nOtx8hwH Og8Q== X-Forwarded-Encrypted: i=1; AJvYcCV08vCtlneAOca52PD70Vv11HJddEyeNM9WrNaXIsHNGwbcbrYOwzBwdr/ZLllNeehTaVhZAWzwRdiF5Sk=@vger.kernel.org X-Gm-Message-State: AOJu0YzxgRGo9dj5x80c8GrwLYWvaGdw+hETvJof7pkT5R8VAXe7nzEO yytMsDrmeCla/6BVZwfptQFbH2To5DmlmeVnhm3zq5RRVT267Xo8YKTnhgmb6x/Fq3+ErW7XR0s GI4KBv++5M8ytfBMf933vRxeVtgtCKDLOhVj2cLYuLCi/BFkY5H8/tfn5YWg= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a4a:df41:0:b0:662:f7a0:e489 with SMTP id 006d021491bc7-662f7a0e5b2mr1686821eaf.19.1769596827494; Wed, 28 Jan 2026 02:40:27 -0800 (PST) Date: Wed, 28 Jan 2026 02:40:27 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6979e79b.050a0220.c9109.003a.GAE@google.com> Subject: [syzbot] [kernel?] KMSAN: uninit-value in task_tick_fair From: syzbot To: anna-maria@linutronix.de, frederic@kernel.org, linux-kernel@vger.kernel.org, mingo@kernel.org, syzkaller-bugs@googlegroups.com, tglx@kernel.org Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: c133687c2eae Merge tag 'spi-fix-v6.19-rc6' of git://git.ke.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=15a2613a580000 kernel config: https://syzkaller.appspot.com/x/.config?x=8bf02b9e495b9fcd dashboard link: https://syzkaller.appspot.com/bug?extid=f840ef7a3be3a331093f compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/b53ff2d374b2/disk-c133687c.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/f9212dd806c1/vmlinux-c133687c.xz kernel image: https://storage.googleapis.com/syzbot-assets/a04bd8516c52/bzImage-c133687c.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+f840ef7a3be3a331093f@syzkaller.appspotmail.com ===================================================== BUG: KMSAN: uninit-value in entity_tick kernel/sched/fair.c:5526 [inline] BUG: KMSAN: uninit-value in task_tick_fair+0x46e/0xbe0 kernel/sched/fair.c:13374 entity_tick kernel/sched/fair.c:5526 [inline] task_tick_fair+0x46e/0xbe0 kernel/sched/fair.c:13374 sched_tick+0x270/0xdf0 kernel/sched/core.c:5535 update_process_times+0x27e/0x2d0 kernel/time/timer.c:2479 tick_sched_handle kernel/time/tick-sched.c:298 [inline] tick_nohz_handler+0x5a0/0x7f0 kernel/time/tick-sched.c:319 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x559/0xd70 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x456/0xb70 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0xaa/0x420 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x7f/0x90 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:697 memmove+0x28/0x1b0 arch/x86/lib/memmove_64.S:45 Uninit was created at: __alloc_frozen_pages_noprof+0x41c/0xaa0 mm/page_alloc.c:5263 alloc_pages_mpol+0x328/0x860 mm/mempolicy.c:2486 alloc_frozen_pages_noprof+0xf6/0x200 mm/mempolicy.c:2557 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x1ea/0x1700 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0x1048/0x38c0 mm/slub.c:4656 __slab_alloc+0xa3/0x180 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] __kmalloc_cache_noprof+0x9e0/0x1710 mm/slub.c:5775 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] device_private_init drivers/base/core.c:3534 [inline] device_add+0x101/0x1c10 drivers/base/core.c:3585 usb_add_gadget+0x72e/0xe70 drivers/usb/gadget/udc/core.c:1434 usb_add_gadget_udc_release drivers/usb/gadget/udc/core.c:1484 [inline] usb_add_gadget_udc+0x11f/0x1a0 drivers/usb/gadget/udc/core.c:1531 dummy_udc_probe+0xbe6/0x10f0 drivers/usb/gadget/udc/dummy_hcd.c:1099 platform_probe+0x213/0x370 drivers/base/platform.c:1446 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x4d4/0xdc0 drivers/base/dd.c:659 __driver_probe_device+0x25e/0x370 drivers/base/dd.c:801 driver_probe_device+0x70/0x8f0 drivers/base/dd.c:831 __device_attach_driver+0x4ee/0x950 drivers/base/dd.c:959 bus_for_each_drv+0x3e3/0x680 drivers/base/bus.c:500 __device_attach+0x3c5/0x5f0 drivers/base/dd.c:1031 device_initial_probe+0x126/0x170 drivers/base/dd.c:1086 bus_probe_device+0x287/0x550 drivers/base/bus.c:574 device_add+0x12a9/0x1c10 drivers/base/core.c:3689 platform_device_add+0x7ee/0xab0 drivers/base/platform.c:757 dummy_hcd_init+0xb2f/0x11b0 drivers/usb/gadget/udc/dummy_hcd.c:2866 do_one_initcall+0x22b/0xad0 init/main.c:1378 do_initcall_level+0x157/0x2e0 init/main.c:1440 do_initcalls+0x176/0x310 init/main.c:1456 do_basic_setup+0x1d/0x30 init/main.c:1475 kernel_init_freeable+0x213/0x430 init/main.c:1688 kernel_init+0x2f/0x5e0 init/main.c:1578 ret_from_fork+0x207/0x6f0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 CPU: 0 UID: 0 PID: 7329 Comm: syz.7.249 Tainted: G L syzkaller #0 PREEMPT(voluntary) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 ===================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup