From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2259AE7717F for ; Mon, 16 Dec 2024 10:41:39 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.857703.1269917 (Exim 4.92) (envelope-from ) id 1tN8XV-0000gq-Cc; Mon, 16 Dec 2024 10:41:25 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 857703.1269917; Mon, 16 Dec 2024 10:41:25 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1tN8XV-0000gj-9a; Mon, 16 Dec 2024 10:41:25 +0000 Received: by outflank-mailman (input) for mailman id 857703; Mon, 16 Dec 2024 10:41:24 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1tN8XU-0000gN-PO for xen-devel@lists.xenproject.org; Mon, 16 Dec 2024 10:41:24 +0000 Received: from mail-wm1-x32b.google.com (mail-wm1-x32b.google.com [2a00:1450:4864:20::32b]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id 4b8969a1-bb9a-11ef-a0d6-8be0dac302b0; Mon, 16 Dec 2024 11:41:24 +0100 (CET) Received: by mail-wm1-x32b.google.com with SMTP id 5b1f17b1804b1-435f8f29f8aso27679565e9.2 for ; Mon, 16 Dec 2024 02:41:24 -0800 (PST) Received: from [10.156.60.236] (ip-037-024-206-209.um08.pools.vodafone-ip.de. [37.24.206.209]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-436360154c7sm80505735e9.1.2024.12.16.02.41.22 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 16 Dec 2024 02:41:23 -0800 (PST) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 4b8969a1-bb9a-11ef-a0d6-8be0dac302b0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1734345683; x=1734950483; darn=lists.xenproject.org; h=content-transfer-encoding:in-reply-to:autocrypt:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:from:to:cc:subject:date:message-id:reply-to; bh=U472/Npzn+Rc8KBcwENfcdFf4Nfo53RnxwaAKI9LbU8=; b=WCWj9amvLdMA47cjPR95ozmLg16WcUDCtnmPuZGPhGwUUtew6zGBOwfDh17CmrC2s9 AYnI1LFUko6DhfUzL5EbGLlEYz9gk1AdumF9CyDMlJ3eCnuNlq2EFNsRYN7KgxYWz9NM KkXOyA7UrTftaxGJ7b81ifx2bvidsjGQBsOIKpdcOCB4aRkpOXceo0M/D/7+Plyqs7a7 rBx2wzW/Hbsp7ac7JJhY6ZgBLJIDgKldw78K9vX+R4Ibs3KdwZnOHXFHGEQGJLCWiQMH pWhGbGcmVTYmpiIyEqhMCbfnGPP8sZSCvI/o/rS9htJxEbApj1/BYZ1DPRgD6rli9cCS M6dA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1734345683; x=1734950483; h=content-transfer-encoding:in-reply-to:autocrypt:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=U472/Npzn+Rc8KBcwENfcdFf4Nfo53RnxwaAKI9LbU8=; b=kfMda5pA7B5w3hBjPU3WZE+EJ3ocTk5+ni5nw7whMQRFyipzTKUqf+Q5IsdkQ8HCBv qQoKpbEHdY5hIk4IaVhi4RhB0oG2+HEZTAY5XjUWL0Y+fP86y4HAvC7VwBcs2XsiWuWi DA4C6ZgTAZ70RoLazNOtuY9mWhlqRMeCXM5Nm1iZdNk9xB9ObceJPjQssoMOYOBQpgnj FQJPgYon6B/eynvWEdeoctwDTlRSALexAi/7AcUR1jKmEgUrYjkEaIM8/atUGG4pPXdB ojs3CXOJ3csNN8RNFBKmJfOv2dzezv9WTfx355IojwFjvpzmBc0USCSZpQ2ydKvBFINr lQ3A== X-Forwarded-Encrypted: i=1; AJvYcCVgVfPz7lN+0xpei4bVuOwfP8tFfDjW8AnfjpG3daKgktCOkhHxIzjk5OvheVnz77KYqrqL8AetRn4=@lists.xenproject.org X-Gm-Message-State: AOJu0YxmARIVHv0prmlqpz4sY6Cn/ZxInNaivRnPgp8nJEy+RF++w/YE 0hzxWSwOFAg5qsrrP+2W1o2IOqVe9XaeBrZ4rR3kuiEkvxBhewtjrF0v0DJjBg== X-Gm-Gg: ASbGncsFKgL6M2V4YfLvmtzSXdYrBj2eSOI79UoVltvtcXKTH7LogsScdLTHBsp/7We 9jc2phjL1sMHTCB+eVZ2OF7Uepdxnta53/KiyPlHiPmE7jvMi/91ZUZYcH3LNBjLUY6x/i+hegY qNUByOLWA5WXyFuGmcDkhVQv4taPbci9fZy4vM2mSP9Ql4zlYZkfjrSmZ4JuNjdntE2c77N1Sbd UaEDC851hEwLj51rpZwzal7KLIa6/UtYswxaV12FBXqjWM+mp/tCwQEtUL/xI/i4eEdLhgw4zeZ QylpOsyr8hGCA8AD/005I2FcL9ejiJKDlXsNF2gqLQ== X-Google-Smtp-Source: AGHT+IH8GlOnrPLZYbXM5JU1fntsaCPcyTL3jUF4/R+hjyeUPoWTONv/YYBXb9eX95sks1ySRhfN9g== X-Received: by 2002:a05:600c:468b:b0:434:f871:1b96 with SMTP id 5b1f17b1804b1-4362aab4cb4mr101242055e9.29.1734345683429; Mon, 16 Dec 2024 02:41:23 -0800 (PST) Message-ID: Date: Mon, 16 Dec 2024 11:41:25 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 5/7] xen: add new domctl get_changed_domain To: Juergen Gross Cc: "Daniel P. Smith" , Anthony PERARD , Andrew Cooper , Michal Orzel , Julien Grall , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= , Stefano Stabellini , xen-devel@lists.xenproject.org References: <20241213162421.16782-1-jgross@suse.com> <20241213162421.16782-6-jgross@suse.com> Content-Language: en-US From: Jan Beulich Autocrypt: addr=jbeulich@suse.com; keydata= xsDiBFk3nEQRBADAEaSw6zC/EJkiwGPXbWtPxl2xCdSoeepS07jW8UgcHNurfHvUzogEq5xk hu507c3BarVjyWCJOylMNR98Yd8VqD9UfmX0Hb8/BrA+Hl6/DB/eqGptrf4BSRwcZQM32aZK 7Pj2XbGWIUrZrd70x1eAP9QE3P79Y2oLrsCgbZJfEwCgvz9JjGmQqQkRiTVzlZVCJYcyGGsD /0tbFCzD2h20ahe8rC1gbb3K3qk+LpBtvjBu1RY9drYk0NymiGbJWZgab6t1jM7sk2vuf0Py O9Hf9XBmK0uE9IgMaiCpc32XV9oASz6UJebwkX+zF2jG5I1BfnO9g7KlotcA/v5ClMjgo6Gl MDY4HxoSRu3i1cqqSDtVlt+AOVBJBACrZcnHAUSuCXBPy0jOlBhxPqRWv6ND4c9PH1xjQ3NP nxJuMBS8rnNg22uyfAgmBKNLpLgAGVRMZGaGoJObGf72s6TeIqKJo/LtggAS9qAUiuKVnygo 3wjfkS9A3DRO+SpU7JqWdsveeIQyeyEJ/8PTowmSQLakF+3fote9ybzd880fSmFuIEJldWxp Y2ggPGpiZXVsaWNoQHN1c2UuY29tPsJgBBMRAgAgBQJZN5xEAhsDBgsJCAcDAgQVAggDBBYC AwECHgECF4AACgkQoDSui/t3IH4J+wCfQ5jHdEjCRHj23O/5ttg9r9OIruwAn3103WUITZee e7Sbg12UgcQ5lv7SzsFNBFk3nEQQCACCuTjCjFOUdi5Nm244F+78kLghRcin/awv+IrTcIWF hUpSs1Y91iQQ7KItirz5uwCPlwejSJDQJLIS+QtJHaXDXeV6NI0Uef1hP20+y8qydDiVkv6l IreXjTb7DvksRgJNvCkWtYnlS3mYvQ9NzS9PhyALWbXnH6sIJd2O9lKS1Mrfq+y0IXCP10eS FFGg+Av3IQeFatkJAyju0PPthyTqxSI4lZYuJVPknzgaeuJv/2NccrPvmeDg6Coe7ZIeQ8Yj t0ARxu2xytAkkLCel1Lz1WLmwLstV30g80nkgZf/wr+/BXJW/oIvRlonUkxv+IbBM3dX2OV8 AmRv1ySWPTP7AAMFB/9PQK/VtlNUJvg8GXj9ootzrteGfVZVVT4XBJkfwBcpC/XcPzldjv+3 HYudvpdNK3lLujXeA5fLOH+Z/G9WBc5pFVSMocI71I8bT8lIAzreg0WvkWg5V2WZsUMlnDL9 mpwIGFhlbM3gfDMs7MPMu8YQRFVdUvtSpaAs8OFfGQ0ia3LGZcjA6Ik2+xcqscEJzNH+qh8V m5jjp28yZgaqTaRbg3M/+MTbMpicpZuqF4rnB0AQD12/3BNWDR6bmh+EkYSMcEIpQmBM51qM EKYTQGybRCjpnKHGOxG0rfFY1085mBDZCH5Kx0cl0HVJuQKC+dV2ZY5AqjcKwAxpE75MLFkr wkkEGBECAAkFAlk3nEQCGwwACgkQoDSui/t3IH7nnwCfcJWUDUFKdCsBH/E5d+0ZnMQi+G0A nAuWpQkjM1ASeQwSHEeAWPgskBQL In-Reply-To: <20241213162421.16782-6-jgross@suse.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 13.12.2024 17:24, Juergen Gross wrote: > --- a/xen/common/domain.c > +++ b/xen/common/domain.c > @@ -193,6 +193,57 @@ static void domain_changed_state(const struct domain *d) > spin_unlock(&dom_state_changed_lock); > } > > +static void set_domain_state_info(struct xen_domctl_get_domain_state *info, > + const struct domain *d) > +{ > + info->state = XEN_DOMCTL_GETDOMSTATE_STATE_EXIST; > + if ( d->is_shut_down ) > + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_SHUTDOWN; > + if ( d->is_dying == DOMDYING_dying ) > + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DYING; > + if ( d->is_dying == DOMDYING_dead ) > + info->state |= XEN_DOMCTL_GETDOMSTATE_STATE_DEAD; > + info->unique_id = d->unique_id; > +} > + > +int get_domain_state(struct xen_domctl_get_domain_state *info, struct domain *d, > + domid_t *domid) > +{ > + unsigned int dom; > + > + if ( info->pad0 || info->pad1 ) > + return -EINVAL; > + > + if ( d ) > + { > + set_domain_state_info(info, d); > + > + return 0; > + } > + > + while ( (dom = find_first_bit(dom_state_changed, DOMID_MASK + 1)) < > + DOMID_FIRST_RESERVED ) > + { > + if ( test_and_clear_bit(dom, dom_state_changed) ) For these two accesses to dom_state_changed don't you need to hold the lock patch 4 introduces? Also didn't you say you'd constrain the new sub-op to the sole domain having VIRQ_DOM_EXEC bound (which, ftaod, isn't enough to eliminate the race)? > + { > + *domid = dom; > + > + d = rcu_lock_domain_by_id(dom); > + > + if ( d ) > + { > + set_domain_state_info(info, d); > + > + rcu_unlock_domain(d); > + } Oh, on the implicit "else" is where the original memset() would come into play: You want to make sure at least ->state, but perhaps also ->unique_id are cleared (rather than demanding the caller to clear them ahead of making the call). Jan