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AJvYcCV8vEkN30S277H5pp4cMK4GmuOAvV5xcar83+ADSXOY1uXI9RHTwupip3EfwrUE63P675UXxMLDig==@vger.kernel.org X-Gm-Message-State: AOJu0YzJFgoYhpiCcZlRIuHzW96/dHSnO5q+XAhY7rzwf+oC3GUAWnJx kgza49DnMIidc31jvPIp4Z5RnQWq3pCHlJjaK//Hxloz4AeNYUQIYlBsoQ9D30I= X-Gm-Gg: ASbGncs9Dzlgyksqh/SgrtLYHGGPkeyV+TzLBluLQingYdbjESQNk0vQoy+g68rPkh3 P5NafWNNK5sv03vyuM+Hzd0ZIhlmpA/ZbLEzC51LqfBKaIMnoaz0NBQjF+wN9FzDc0aFGsyLn8v fBgVNZwVM1whuQc0RIU9DUa6NvxpWCDkwr4AFQeq/h3afiGJ7JKJVCQ/UpIg3eY1LokLa/MBQL2 m+c6znMGR85YkOaWbAj5imnreu683Ar1B9Z4+7+nHae4xyUWZWn X-Google-Smtp-Source: AGHT+IE/Xq/L3NZJczlwQ4pSaUcLJdPCpkw+bO4k0tQkMeu6oZebS/7lMFWakB32yx9P79/WHZSehA== X-Received: by 2002:a05:6602:4891:b0:847:4fc0:c6c3 with SMTP id ca18e2360f4ac-84ce0125306mr2808888739f.7.1736960856265; Wed, 15 Jan 2025 09:07:36 -0800 (PST) Received: from [192.168.1.116] ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id ca18e2360f4ac-84d61fc811esm408728039f.42.2025.01.15.09.07.34 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 15 Jan 2025 09:07:35 -0800 (PST) Message-ID: Date: Wed, 15 Jan 2025 10:07:34 -0700 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: futex+io_uring: futex_q::task can maybe be dangling (but is not actually accessed, so it's fine) To: Thomas Gleixner , Peter Zijlstra Cc: Jann Horn , Ingo Molnar , Darren Hart , Davidlohr Bueso , =?UTF-8?Q?Andr=C3=A9_Almeida?= , kernel list , Pavel Begunkov , io-uring References: <3b78348b-a804-4072-b088-9519353edb10@kernel.dk> <20250113143832.GH5388@noisy.programming.kicks-ass.net> <877c6wcra6.ffs@tglx> <30a6d768-b1b8-4adf-8ff0-9f54edde9605@kernel.dk> <5603e468-9891-46a3-9ef7-13830cc975e5@kernel.dk> <87msfsatyb.ffs@tglx> Content-Language: en-US From: Jens Axboe In-Reply-To: <87msfsatyb.ffs@tglx> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 1/15/25 10:05 AM, Thomas Gleixner wrote: > On Wed, Jan 15 2025 at 08:32, Jens Axboe wrote: >> Here's the raw patch. Should've done this initially rather than just >> tackle __futex_queue(), for some reason I thought/assumed that >> futex_queue() was more widely used. > > 'git grep' is pretty useful to validate such assumptions :) It would not be a good assumption if it was backed by fact checking ;-) >> What do you think? > > Looks about right. OK thanks, fwiw I did send it out as a proper patch as well. -- Jens Axboe