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AJvYcCX8Hj1jewc4RFPa3yDud0Bj5Uk7B2WWkpZwbHEt/e/KViXi2pgqlePCtPkciG2E9hfDjjZ1v51Vky2/SlWXDaAPy2BRviGxlNk= X-Gm-Message-State: AOJu0YyzDqn03YjUuRE5K3y/V/g6gpYPof/QZMYl8CFrRXv2MgaIzSTs HXy0ciOCS/RXNR3CNMNQCp5uW8k3afBAn2mkO7/NxpXj5+61u5tCQEKvjOWQphM= X-Google-Smtp-Source: AGHT+IEaOzeK0O5UbyTTDtFYjiHqeN5WenoQZb1OoHTZenXrLhcCOyFGivw8jmZhFIRfjQBImMMn1Q== X-Received: by 2002:a5e:c105:0:b0:7f9:3fd9:cbd with SMTP id ca18e2360f4ac-81f7cf3f757mr33863139f.0.1721855087435; Wed, 24 Jul 2024 14:04:47 -0700 (PDT) Received: from [192.168.1.116] ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id 8926c6da1cb9f-4c28c9384bcsm584489173.100.2024.07.24.14.04.46 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 24 Jul 2024 14:04:46 -0700 (PDT) Message-ID: <82a0cfca-c1d2-4d53-a00d-8283ddd81621@kernel.dk> Date: Wed, 24 Jul 2024 15:04:46 -0600 Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [syzbot] [io-uring?] KMSAN: uninit-value in io_req_task_work_add_remote To: syzbot , asml.silence@gmail.com, io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com References: <000000000000a4fe65061e049a02@google.com> Content-Language: en-US From: Jens Axboe In-Reply-To: <000000000000a4fe65061e049a02@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/24/24 3:03 PM, syzbot wrote: > Hello, > > syzbot has tested the proposed patch and the reproducer did not trigger any issue: > > Reported-by: syzbot+82609b8937a4458106ca@syzkaller.appspotmail.com > Tested-by: syzbot+82609b8937a4458106ca@syzkaller.appspotmail.com > > Tested on: > > commit: c33ffdb7 Merge tag 'phy-for-6.11' of git://git.kernel... > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=17d29bb5980000 > kernel config: https://syzkaller.appspot.com/x/.config?x=f26f43c6f7db5ad2 > dashboard link: https://syzkaller.appspot.com/bug?extid=82609b8937a4458106ca > compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 > patch: https://syzkaller.appspot.com/x/patch.diff?x=120b7dad980000 > > Note: testing is done by a robot and is best-effort only. As I figured... No idea what's going on here, nr_tw is what is being complained about and it's _clearly_ initialized. Randomly disabling a branch that won't touch it off this path (hence it should be a no-op in terms of code executed messing with nr_tw) makes it go away. -- Jens Axboe