From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=209.85.214.182 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794335400; b=SVwMf4XnBQfk/QmTMjJv/k74zdrudlcroqh3VKhnRSBBRLMhwt7lM3pjteF2vZGeVs4g CzKvVR4kyoE59pFyIGLEsAkiqxsFtpSGsLRN2tBOtVirXx0F0KzRsF4t7gserojUr8bET ud5cXPBBw06iGswZ0VthXR1SIiQFD+K8nky5dSNISb7hmLJ7m/Kd3/nzzyaShWyXUfTpA U0MzJXQa9f57FvwQRX59tJegRjLter3FiUdcN7qE8rApl1NaInxMxTVuSH2v/NyM6YjqZ 2W9M2kUsVP1vybGiWYOzWoax6Em2jMc9QDaBLomKpNShmQ02sIAX/oveDv7rZuVuI+g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794335400; h=DMARC-Filter:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Forwarded-Encrypted:X-Gm-Message-State:X-Gm-Gg:X-Received:Received: Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; bh=h/fDqdjeF2qNLQi3iaEH9vKqxnzXslPVSp3ugOVQ8hM=; b=ME9o0TpBDTdVjevys+kCfvIggOySAnqfJlAjRritFinsufj/RC1u9w6V0zgQuFQPJpKz ldvfO54rVyIP0HFTvSX36I2N/QMX7awVA4P2CPBeewZZ2A2TRMseRntxRDzBjm6F36Z89 YqhvdcpN7Cpc+EXhz7jkPDDWBhTfxEwXyaxxXfqOPUPg+gXy0kRyf2bw300onW+reZx9V rg2o8mGSOqiULPM1drEXX4e7IMzfn7KU16he/sbc1/ag+8Q1vPBjRavhhA1w3296AqoYK uHtPEq81NhWBHNY5X+T9rLBRIfzlfjoPtAm1i+Vc6lVUuwnGrWNBf5I67ES9OnakVHA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=google.com; spf=pass smtp.mailfrom=google.com; dkim=pass header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20260707 header.b=UdZdxJ6r; arc=none smtp.remote-ip=209.85.214.182 Received: from mail-pl1-f182.google.com (mail-pl1-f182.google.com [209.85.214.182]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 88CA4606A321 for ; Tue, 10 Nov 2026 18:29:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 88CA4606A321 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20260707 header.b=UdZdxJ6r Received: by mail-pl1-f182.google.com with SMTP id d9443c01a7336-2e9f6a16afcso2455ad.1 for ; Tue, 10 Nov 2026 10:29:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20260707; t=1794335399; x=1794940199; darn=vger.kernel.org; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:from:to:cc:subject :date:message-id:reply-to:content-type; bh=h/fDqdjeF2qNLQi3iaEH9vKqxnzXslPVSp3ugOVQ8hM=; b=UdZdxJ6rNZ3/kHowGOj5UNEdj7VsXtZug1Xb+yHljvFikFaUgmIpizg0NW0XHdGMVV PPOFVU7beNKvrmucaZ5hxkrE7+2gYv/Wka3wiiiieRRHtX7lLKr3F6yUarxVPYUCA2Fj Bpz74oq39RsKDrsPVzn3PUk3xfuts/+HurVfedeOrGe9i+CW4cWXOdvLTuo7XhLvznwx dW5VF0GzV1IAqpt8bwmJRvW47AlpZrWOnW2zL2euvhNvY8C0QjB2jkjLxUwfpXYjVcLD QQBazrZjNYXOhQU3wC76bm8PgtoYUn+bfik8AWnFXvJCKAj1FGejcs0ZgJO22cDIkdUb oLGw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1794335399; x=1794940199; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=h/fDqdjeF2qNLQi3iaEH9vKqxnzXslPVSp3ugOVQ8hM=; b=TFU5lKU7/Y3sz4mtHAEdEHKSyTbmHm3YP9dHQQ+fHxpHjR1mUp8X+iEDv0qJc6vDvD Q7k5j0Pcyi26UFtujjPfD+YRMhE2m/v8ehMdS7sRAL31cC1X6vhSVx+XAtqEp/3tgpRd e6ESl5lHBd2YCpPfS3FtrVEXvcLmOtTaaM7xz7n59JeJ4iMZsPQVsdioOP4/zM/EKGm7 7dRqDjJADD7uRJCcwbJ1RBlMAGVhewW8BRBNUPjuw2E0JwYD/OTnd8N2+7WRbuJtXz+I OZZBuYx5Q/yxGN2zZuCR9V3UFs6k21ycFyraHdxXDfKfApmjvoLgUR89/y3055E9o9qD BsnA== X-Forwarded-Encrypted: i=1; AL+hErEA3i8gMPnWC1W0+1xBicB/VNCRr63WaQVbaarBu3NF2mQQH8Dd0iCDqjtnh86D3Cus07BqZAr8Txu1nZk=@vger.kernel.org X-Gm-Message-State: APuU4Z/n1lMf+ePA3F1ipoL9Qq3Ig2mS6mJGXEPavZ8qLzW9kckIuCjf bTbG9EHeQDmvXsvQ7GtOVo7tXijLehLtH0wmN0Sr2j3Z02Wf3Ky+Fdej5W4GQReZWA== X-Gm-Gg: AYBFou0BuaTxp7Vzgcf0ODvYDZW1mmxkQnOSJWvqxL3VCoQbysESMfgb31qw2Hi3JG8 aE9Btl2ebFgeS6P9DDJuB/xZNMYih205sj4Km1Tksii2Os5L+ufT85QCA6ZppkeJ2oQBBbSv4cD OORbtActdG2mq4yhwxIl7d9as94YUT0IamrNXCaLgF3uKKvJ9RyDj8AQMRfTbXYY2dfTTl3IBoO RMwGoDOhJgd/vZ3Iyyi/GbbURaThPIqk5JSG8VMFmDua1S9NYqqO5hhNHEx0WNca1Q/sZos2v5k r4durWFhokxtt3HJ87oNAmrFhi6NpHTAdmkLjt9gl2SJ9KHX9Yh2QgLSvuZYitfQlKx9sYifLBj DzPD5cX3pxilUSq1m4Qt5YX9DQj5txNcY/orOTDXFl7HN8nODSbgdT0AEuUX3yJHgatD8ad5+Ah BbZQZwQjWrvhtcnXN9+2ImFkSUrsbBzSYQEygGOsWu1JxkJLZ0GRGLbh2wZkGlD9loraaZZwxkV ipplO70AAIdUoB2cesFekkwqHuu651VLAMQqj6AA42xtr2BuEMwB2MzhnT6KjxiJErK8ESjMPMz mBewfGZmj1hW1JF8o85JC8/upr9SsIKpiqq2D6ddaoKPSXmYfW3Sj1Q07MZZaO44PAOww5Z3KIR 0PJOetBYyPpTxciHFspVimZIBP1bcrL209dhUJsL7BvE= X-Received: by 2002:a17:902:ce04:b0:2c9:b404:b55 with SMTP id d9443c01a7336-2edb81c27e3mr6143235ad.6.1794335398359; Tue, 10 Nov 2026 10:29:58 -0800 (PST) Received: from google.com (25.75.145.34.bc.googleusercontent.com. [34.145.75.25]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2edb6a4013csm12795005ad.1.2026.11.10.10.29.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Nov 2026 10:29:57 -0800 (PST) Date: Tue, 10 Nov 2026 18:29:54 +0000 From: Samiullah Khawaja To: Pratyush Yadav Cc: Pasha Tatashin , Mike Rapoport , Andrew Morton , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v2 1/2] liveupdate: luo_file: allow keeping private_data from retrieve until finish Message-ID: References: <20261110175855.2437084-1-pratyush@kernel.org> <20261110175855.2437084-2-pratyush@kernel.org> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20261110175855.2437084-2-pratyush@kernel.org> On Tue, Nov 10, 2026 at 06:58:52PM +0100, Pratyush Yadav wrote: >From: "Pratyush Yadav (Google)" > >The private_data field of struct liveupdate_file_op_args lets file >handlers keep runtime state that is not preserved. It is set by >.preserve() and passed to the later outgoing callbacks, up to >.unpreserve(). But in the new kernel, nothing set by .retrieve() is >kept, and .can_finish() and .finish() always get a NULL private_data. > >Handlers might need to keep runtime state from retrieve until finish. >For example, memfd will need to remember the folios it holds on to >until finish so it can release them there. > >Save the private_data set by a successful .retrieve() in the luo_file, >and pass it to .can_finish() and .finish(). The handler must free it in >.finish(). > >While at it, update a stale comment under struct >liveupdate_file_op_args. There is no 'data', but there is >'serialized_data' and 'private_data'. Refer to them instead. > >Reviewed-by: Pasha Tatashin >Signed-off-by: Pratyush Yadav (Google) >--- > include/linux/liveupdate.h | 11 +++++++---- > kernel/liveupdate/luo_file.c | 11 ++++++++--- > 2 files changed, 15 insertions(+), 7 deletions(-) > Reviewed-by: Samiullah Khawaja