From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f72.google.com (mail-ot1-f72.google.com [209.85.210.72]) (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 D046A1D435F for ; Mon, 26 Jan 2026 05:36:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.72 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769405765; cv=none; b=QP6KDPq2iK8GltTGQqqqShHtwW7fa7PmG77qehJK6bRyZExyhrMFDBe+GtyI8yTZxUWNHPc4c4i/fjpdGx1vOcgZWBzplY7TPYcFV3JJUe2e6hRaR4Hp69CEIoH4wGtt+Mx2gdSJ/jB2Rt2nbF+yLISjzCFpOCcekJ3q317fCo4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769405765; c=relaxed/simple; bh=u+wufOLgzMdU5OXlg6eV4QjL5AsqmqMywAYa+KDd3qQ=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=XfqY2vYW8Huf8jsTyh3E5aTY5+DmY1DPNW++YahanaOoeaVH1CaG2lao5RNNgi9OPUEfW7H8QBFg3ng0OXGwCyNe20qHb1v7sgmFRpmNMWp8ObhGZDlO3MROdGQax66IachcrbDuDqZVccxbE2z3gkmE3KfOo0zavdBGWKK8j1k= 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=209.85.210.72 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-f72.google.com with SMTP id 46e09a7af769-7cfd3cbaeedso16543311a34.1 for ; Sun, 25 Jan 2026 21:36:03 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1769405763; x=1770010563; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=0GpDIqfUJtnXRuuN8ZHlyqyZoFT1wtgcoWh7JcZeeUM=; b=bFBcu8Y+mwl8Oo5p4jl/Fti+TTAzLFg4HX77elFPTyEt2jCzfqmhs0sZW10gm4TVkL ymx3D6YTMJTWcdkGny9NprBvh2fpdbE4HSscKVX7Ea7Ql40m9axJMlFc1Qlgg6e7fXvF 0vAZY2pptZk0YcSx1RSf5Tc1kEiPqe0N8E7bPs5Eh+5K+jjJo7nerLNsz88uF2aZdTHg eh8yEtPHRFLJ4OXzQBstv00nQCvOws3GxwShytzK/EfAGZP1SaWknX3IXSq/CZitq8mV dNhyVVOhPQctI5JOSPkZ6vbQmNijQjyLYzGKCaZpI7OENclmU02zqP9P+2FYLbkv94X8 2/tw== X-Forwarded-Encrypted: i=1; AJvYcCUnkfofKti5gcIAOV0LpN64XWNf0l6hUUwmjuwqOeYFgzQHe9K38qyumcu8HUD8utnI+zForD8O1um/zWA=@vger.kernel.org X-Gm-Message-State: AOJu0Yz7d4fiPl3G41QH6sgV32GhCx6hgi+OqMF4du9sdU+MPnnd+Prv cxCH0a3Ukgzy6te4k6ZvZIRv4NX7/IKqlkEz/5cEthK7oDcg1y/7Ax/FlTw+MaiCdXiBAeL2dLa GMoByowaYPT8VkPivnUgMUPY6rugLK13m/2QVWO17swhhVEv1Y/pF4WE8Krw= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:994:b0:662:c928:31a2 with SMTP id 006d021491bc7-662e03ec3d4mr1913184eaf.23.1769405762859; Sun, 25 Jan 2026 21:36:02 -0800 (PST) Date: Sun, 25 Jan 2026 21:36:02 -0800 In-Reply-To: <20260126051936.5684-1-kartikey406@gmail.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6976fd42.050a0220.226181.0012.GAE@google.com> Subject: Re: [syzbot] [comedi?] BUG: unable to handle kernel paging request in dt2815_attach From: syzbot To: kartikey406@gmail.com, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot has tested the proposed patch but the reproducer is still triggering an issue: BUG: unable to handle kernel paging request in dt2815_attach dt2815: After second outb dt2815: Loop iteration 1, dev->iobase = 0x7d dt2815: status = 0xff dt2815: About to do second outb, dev = ffff8880408c7000, dev->iobase = 0x7d BUG: unable to handle page fault for address: 000000007fffff90 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 465c6067 P4D 465c6067 PUD 0 Oops: Oops: 0002 [#1] SMP KASAN NOPTI CPU: 0 UID: 0 PID: 5846 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:__outb arch/x86/include/asm/shared/io.h:22 [inline] RIP: 0010:dt2815_attach+0x6a8/0x9e0 drivers/comedi/drivers/dt2815.c:210 Code: 8b 96 d0 01 00 00 48 c7 c7 e0 f7 8b 8c 4c 89 f6 e8 7d 5f f5 ff 43 80 3c 27 00 74 08 4c 89 ef e8 ce 02 f9 00 41 8b 55 00 ff c2 <31> 66 90 48 c7 c7 60 f8 8b 8c e8 59 5f f5 ff 83 fd 63 75 9c eb 71 RSP: 0018:ffffc90001987a80 EFLAGS: 00010206 RAX: 000000000000004b RBX: ffffc90001987bc0 RCX: fd82e65c6f5c7300 RDX: 000000000000007e RSI: 0000000080000000 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffc90001987807 R09: 1ffff92000330f00 R10: dffffc0000000000 R11: fffff52000330f01 R12: dffffc0000000000 R13: ffff8880408c71d0 R14: ffff8880408c7000 R15: 1ffff11008118e3a FS: 00007f4b609056c0(0000) GS:ffff88808cf1b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000007fffff90 CR3: 00000000465ca000 CR4: 0000000000352ef0 Call Trace: comedi_device_attach+0x51f/0x720 drivers/comedi/drivers.c:1069 do_devconfig_ioctl drivers/comedi/comedi_fops.c:928 [inline] comedi_unlocked_ioctl+0x701/0x1240 drivers/comedi/comedi_fops.c:2240 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4b5f99acb9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4b60905028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f4b5fc15fa0 RCX: 00007f4b5f99acb9 RDX: 0000200000000080 RSI: 0000000040946400 RDI: 0000000000000003 RBP: 00007f4b5fa08bf7 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4b5fc16038 R14: 00007f4b5fc15fa0 R15: 00007ffc911b33b8 Modules linked in: CR2: 000000007fffff90 ---[ end trace 0000000000000000 ]--- RIP: 0010:__outb arch/x86/include/asm/shared/io.h:22 [inline] RIP: 0010:dt2815_attach+0x6a8/0x9e0 drivers/comedi/drivers/dt2815.c:210 Code: 8b 96 d0 01 00 00 48 c7 c7 e0 f7 8b 8c 4c 89 f6 e8 7d 5f f5 ff 43 80 3c 27 00 74 08 4c 89 ef e8 ce 02 f9 00 41 8b 55 00 ff c2 <31> 66 90 48 c7 c7 60 f8 8b 8c e8 59 5f f5 ff 83 fd 63 75 9c eb 71 RSP: 0018:ffffc90001987a80 EFLAGS: 00010206 RAX: 000000000000004b RBX: ffffc90001987bc0 RCX: fd82e65c6f5c7300 RDX: 000000000000007e RSI: 0000000080000000 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffc90001987807 R09: 1ffff92000330f00 R10: dffffc0000000000 R11: fffff52000330f01 R12: dffffc0000000000 R13: ffff8880408c71d0 R14: ffff8880408c7000 R15: 1ffff11008118e3a FS: 00007f4b609056c0(0000) GS:ffff88808cf1b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000007fffff90 CR3: 00000000465ca000 CR4: 0000000000352ef0 ---------------- Code disassembly (best guess): 0: 8b 96 d0 01 00 00 mov 0x1d0(%rsi),%edx 6: 48 c7 c7 e0 f7 8b 8c mov $0xffffffff8c8bf7e0,%rdi d: 4c 89 f6 mov %r14,%rsi 10: e8 7d 5f f5 ff call 0xfff55f92 15: 43 80 3c 27 00 cmpb $0x0,(%r15,%r12,1) 1a: 74 08 je 0x24 1c: 4c 89 ef mov %r13,%rdi 1f: e8 ce 02 f9 00 call 0xf902f2 24: 41 8b 55 00 mov 0x0(%r13),%edx 28: ff c2 inc %edx * 2a: 31 66 90 xor %esp,-0x70(%rsi) <-- trapping instruction 2d: 48 c7 c7 60 f8 8b 8c mov $0xffffffff8c8bf860,%rdi 34: e8 59 5f f5 ff call 0xfff55f92 39: 83 fd 63 cmp $0x63,%ebp 3c: 75 9c jne 0xffffffda 3e: eb 71 jmp 0xb1 Tested on: commit: 63804fed Linux 6.19-rc7 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=15ba3002580000 kernel config: https://syzkaller.appspot.com/x/.config?x=e2e5d7c9c1e01cf4 dashboard link: https://syzkaller.appspot.com/bug?extid=72f94b474d6e50b71ffc compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 patch: https://syzkaller.appspot.com/x/patch.diff?x=1214b9ac580000