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AKwUvBxLfOWSsYjzeyIob07YS+Q+i2kDPsGS+jCv87ZIZB5gqSIskdG1cFmJ2214xMGo0yeQwDj+RteFtKR4rxc=@vger.kernel.org X-Gm-Message-State: AFuF++kDPO4+O2EkfvDHhnCO4Q1OPe2jKmRr/kXuMMSIgtYXh8SOBXDN TlrsJ8uXt8ahb9H7s8IimRR6kPWIh8yN8mF6spK8snjwwG6rX7o38f0i6ejr4Dxn6j6R9gAiLq6 q0KRHTEZISGPdn8y2WpDgTQUKV/d7wioLV1n657bqKzjEs/ODm075Z9XHvos= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:4c09:b0:6b7:83c5:fdf4 with SMTP id 006d021491bc7-6b783c603ccmr1554482eaf.53.1788527259249; Fri, 04 Sep 2026 06:07:39 -0700 (PDT) Date: Fri, 04 Sep 2026 06:07:39 -0700 In-Reply-To: <000000000000bce370061f4207cf@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a9ac29b.04649fcc.10325f.0000.GAE@google.com> Subject: Re: [syzbot] [kernel?] WARNING in firmware_fallback_sysfs (2) From: syzbot To: dakr@redhat.com, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, mcgrof@kernel.org, rafael@kernel.org, russ.weight@linux.dev, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" syzbot has found a reproducer for the following issue on: HEAD commit: bc35965f6940 Merge tag 'mm-hotfixes-stable-2026-09-03-17-4.. git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git console output: https://syzkaller.appspot.com/x/log.txt?x=123d08f9580000 kernel config: https://syzkaller.appspot.com/x/.config?x=8c5c3949d762a91f dashboard link: https://syzkaller.appspot.com/bug?extid=8f06445357a052a92657 compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=125c6125580000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+8f06445357a052a92657@syzkaller.appspotmail.com usb 7-1: Falling back to sysfs fallback for: v4l-pvrusb2-160xxx-01.fw ------------[ cut here ]------------ ret WARNING: drivers/base/firmware_loader/fallback.c:158 at fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:158 [inline], CPU#0: pvrusb2-context/2510 WARNING: drivers/base/firmware_loader/fallback.c:158 at firmware_fallback_sysfs+0x6ef/0xc60 drivers/base/firmware_loader/fallback.c:248, CPU#0: pvrusb2-context/2510 Modules linked in: CPU: 0 UID: 0 PID: 2510 Comm: pvrusb2-context 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:fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:158 [inline] RIP: 0010:firmware_fallback_sysfs+0x6ef/0xc60 drivers/base/firmware_loader/fallback.c:248 Code: ff ff e9 2f 42 d0 fa e8 af ab 9b fb e8 6a 31 5f fb 31 ff 89 c3 89 c6 e8 0f a6 9b fb 85 db 0f 84 f5 fa ff ff e8 92 ab 9b fb 90 <0f> 0b 90 48 8b 3c 24 4c 89 e2 48 c7 c6 20 f2 93 8c e8 6b 11 d0 fa RSP: 0018:ffffc90007d1f8d0 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 00000000fffffff5 RCX: 0000000000000000 RDX: ffff88802e7e2580 RSI: ffffffff8670447e RDI: ffff88802e7e2580 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: 00000000fffffff5 R11: 000000000000761b R12: ffffffff8cff0200 R13: ffff888027cff200 R14: 0000000000001770 R15: ffff888027cff210 FS: 0000000000000000(0000) GS:ffff8880d5b60000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f735b1f0980 CR3: 0000000035e42000 CR4: 0000000000352ef0 Call Trace: _request_firmware+0xfd7/0x13c0 drivers/base/firmware_loader/main.c:898 request_firmware+0x35/0x50 drivers/base/firmware_loader/main.c:948 pvr2_locate_firmware+0x8f/0x330 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:1359 pvr2_upload_firmware1+0x1ca/0x920 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:1426 pvr2_hdw_setup_low drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2107 [inline] pvr2_hdw_setup drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2261 [inline] pvr2_hdw_initialize+0x3e6/0x3710 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2338 pvr2_context_check drivers/media/usb/pvrusb2/pvrusb2-context.c:111 [inline] pvr2_context_thread_func+0x253/0x920 drivers/media/usb/pvrusb2/pvrusb2-context.c:158 kthread+0x373/0x450 kernel/kthread.c:436 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 --- If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing.