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[37.24.206.209]) by smtp.gmail.com with ESMTPSA id k6-20020adfb346000000b0033671314440sm14068395wrd.3.2024.01.16.00.30.37 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 16 Jan 2024 00:30:37 -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: 86d7e1f2-b449-11ee-9b0f-b553b5be7939 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1705393838; x=1705998638; darn=lists.xenproject.org; h=content-transfer-encoding:in-reply-to:autocrypt:from:references:cc :to:content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=RtFoBhIyYM1gd4kJx0zYuQLT/8IqznXLoG7zBOemV1c=; b=CykC6ZcEgGhujsRVFqa6EOC9ygeHJOKsS1iArRbySfpV3tkwRF/yVgEaMVzqWLw9d2 FISg3KSJfUyE4edEb3TO5wcXDsknOpWMsI/B5aIowWPq8lzj4HOjTEBhQI1BVcjc56Hh FXFuz68kXvqTgOpw1OkilgQvnifQJQRW+rQhYxh8b9ZVoD6BAgE6xGtrBebnXudXFFii Y8Gm/KCDVrendZwlbc0z5Uja+IRlXNHpXBplGW6/DTC2v9ivQYLRLYra9IPdXWinVJT1 QXIL9H5PYmz2TrjHJkoPInEihYUOPeLxhXgUN6TnWmbDbSqrq5peUY+hwzy0jubQEwrp OuYg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1705393838; x=1705998638; h=content-transfer-encoding:in-reply-to:autocrypt:from:references:cc :to:content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=RtFoBhIyYM1gd4kJx0zYuQLT/8IqznXLoG7zBOemV1c=; b=hQagTPRK9K1+cM0EdP/kRuI8MMqY9Tv+t+5ip8/NQ3mq5t2N0tNL+KIauuyaPNPXx8 E2ufY2jbGqV7HTHktWX/8sAO/rDWFPbvMB0jCWtR3jMvuslTN/qCykbJuxJsYlEvTtOB Mq/Tdj4pQO1U0Haj2sxtCcTI9hks2bOgVLO4TFXz4kWYZk4C/oyImWpXbr68mj5abUSv VjeSrPL3i2WSaWiKuMfCy/r7lWalStubaI8rRnenzd5id1mentDWL6MmmUatwTTAyb/R tLjzJhWk23fU8wY7J9Y76EHkE+zgPa8VCoz2IZ+8SiCke8vRd7Zdj2lBG56Uq5vqsfpj 2EuA== X-Gm-Message-State: AOJu0Yw31p84UmD5FGVRZ7o4tYj0QkG9Ig1tA0nK9PMZ36luiRtS+ZE9 Vo2Zy43h2UOb90f6xLJabsp1XnG18hrZ X-Google-Smtp-Source: AGHT+IESh+7+KZF5W4ImTgiOOQVgZvZbJl0AZl1RChva1WfIqjtsEISFArpm7M4TVk4CBvN+tWp2Aw== X-Received: by 2002:a5d:608b:0:b0:337:3ed6:869d with SMTP id w11-20020a5d608b000000b003373ed6869dmr3347712wrt.93.1705393837971; Tue, 16 Jan 2024 00:30:37 -0800 (PST) Message-ID: Date: Tue, 16 Jan 2024 09:30:36 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 11/22] x86: add a boot option to enable and disable the direct map Content-Language: en-US To: Elias El Yandouzi Cc: Hongyan Xia , Andrew Cooper , George Dunlap , Stefano Stabellini , Wei Liu , Bertrand Marquis , Volodymyr Babchuk , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= , Julien Grall , xen-devel@lists.xenproject.org, Julien Grall References: <20221216114853.8227-1-julien@xen.org> <20221216114853.8227-12-julien@xen.org> <4ab710c3-c628-4bbe-9533-88af75a9b9ec@xen.org> <0dcc54dd-b729-4e20-95af-fa4907a550c6@amazon.com> <6926f363-3994-4059-b7e1-cb8e45367be8@suse.com> 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: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 15.01.2024 15:50, Elias El Yandouzi wrote: > On 12/01/2024 07:47, Jan Beulich wrote: >> On 11.01.2024 19:25, Elias El Yandouzi wrote: >>> How would you proceed? Calling vmap() seems to be a bit overkill for >>> just a temporary mapping and I don't really want to rework this function >>> to use map_domain_page(). >>> >>> In such case, how would you proceed? What do you suggest? >> >> fixmap may be an option to consider, but I also don't see why you >> apparently think using vmap() would be a possibility while at the >> same time making use of map_domain_page() is too much effort. > > I thought about using vmap() as it allows to map a contiguous region > easily. It is also used in the follow-up patch 17/22, so I thought it > could be viable. > > I was reluctant to use map_domain_page() for two reasons. 1) it only > allows to map one page at the time, so I'd need to rework more deeply > the function dmi_iterate() 2) because the mapcache wouldn't be ready to > use at that time, the mapping would end up in PMAP which is meant to map > the page tables, nothing else. Oh, right, this makes sense of course. Jan