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[37.24.206.209]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a5a179c7d7csm747656166b.140.2024.05.14.09.22.59 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 14 May 2024 09:23:00 -0700 (PDT) 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: 3babf022-120e-11ef-909d-e314d9c70b13 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1715703781; x=1716308581; 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=oRpWNAdQnTo0N4docaodQ5ZeZukKlehSHQL6Z/WP0yk=; b=TDVANDcfV7VzAIznUVDPU2NRRJ8IJwsJHpaNWFIhvvovzdZqeKubGtW9ycxel4cP8/ G6F+cjn2Mdb0JcDFLG1OMoTy+2Tq/FhsKzsSCH/BniDD5uVcAafQJqdRHWUAwu7mQwjk fcxyU+KdsOErRCYz8689LshNKSJ5VCt9qUaIQzCXGS6F0TU+0xkezulZ7e/TNrxHxu7p WcPflgqhGGDmaCWBs2qM8lW1oivs18MEeRPzK1XoM/9faPA1IADiYnrTGcnG17FWtcfM WJCNilk8/wzmOHuOn7zOyGaGSREk6Och3bdBzOJ0ILGkaW8SqbXWeV0yiasM8fR/4pAX PUng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1715703781; x=1716308581; 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=oRpWNAdQnTo0N4docaodQ5ZeZukKlehSHQL6Z/WP0yk=; b=N0N0KOYEh9MCvbOjUn66ihofOK1jA3Q27FuJMVN4WadYY5ssDDChCqPL/CVeDgLhE2 eGfSXfUOerNmtAg1J30PeyjuOQoq7JhkXTEJNt/EBpQ7P2BjEr786Df29fj0dhAmJEmM 4+t84aXy+4j3ofazJk8hxBd3aaPbs3g/3xPsq6F7duIkMGwHagYDuzFOVoYXdYtRZPWr 4m2AusLWKxgIVQleQuD/6BEUVnnQfRpnrA3zZZXmcEHqgyD0LyL3P3MX7kLceC3SCMGu 2EjXYU5l/hRpAw/NHIFj1HHfQOYn9s5oGmxpnYOTf6PsanvkKDnAy2MZun8NwHqPCj7l 7DKA== X-Gm-Message-State: AOJu0YyTdPWPNP3ROEV4G3YHQSG7q3OETn5yDhqf5K0DwAzuNceSmzCm u1870BqLKjSgvr5bEgDshcKbuVYWVVUAoBcscL2u/PuBpRQj4AQhd+9L0ZM+Nw== X-Google-Smtp-Source: AGHT+IFRMQjxQ73KMM3725entLj5SIT2+iszFANr7+FRawFJniLXz66SGb/jsIgXE9GoBylDXPfRGA== X-Received: by 2002:a17:906:48cc:b0:a59:cdc9:6fdf with SMTP id a640c23a62f3a-a5a2d54c0c9mr821509366b.4.1715703780751; Tue, 14 May 2024 09:23:00 -0700 (PDT) Message-ID: Date: Tue, 14 May 2024 18:22:59 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH V3 (resend) 14/19] Rename mfn_to_virt() calls Content-Language: en-US To: =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= Cc: xen-devel@lists.xenproject.org, julien@xen.org, pdurrant@amazon.com, dwmw@amazon.com, Stefano Stabellini , Bertrand Marquis , Michal Orzel , Volodymyr Babchuk , Andrew Cooper , George Dunlap , Lukasz Hawrylko , "Daniel P. Smith" , =?UTF-8?Q?Mateusz_M=C3=B3wka?= , Elias El Yandouzi References: <20240513134046.82605-1-eliasely@amazon.com> <20240513134046.82605-15-eliasely@amazon.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: 8bit On 14.05.2024 17:45, Roger Pau Monné wrote: > On Mon, May 13, 2024 at 01:40:41PM +0000, Elias El Yandouzi wrote: >> Until directmap gets completely removed, we'd still need to >> keep some calls to mfn_to_virt() for xenheap pages or when the >> directmap is enabled. >> >> Rename the macro to mfn_to_directmap_virt() to flag them and >> prevent further use of mfn_to_virt(). > > Both here and in the following patch, I'm afraid I'm unsure of it's > usefulness. I'm leaning towards this being code churn for very little > benefit. I expect this patch is a response to an earlier comment of mine. I'm rather worried that at the time this series actually goes in, un-audited mfn_to_virt() uses remain (perhaps because of introduction between patch submission and its committing). Such uses would all very likely end in crashes or worse, but they may not be found by testing. > Also, I'm not sure I see how the patch prevents further usage of > mfn_to_virt(), as (for Arm) the existing macro is not removed. If > anything I would prefer a comment clearly stating that the macro > operates on directmap space, and avoid the name change. But Arm isn't switched to this sparse direct map mode, I think? At which point uses in Arm-specific code continue to be okay. Jan