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[37.24.206.209]) by smtp.gmail.com with ESMTPSA id fl18-20020a05600c0b9200b0041ae0048b5dsm481577wmb.45.2024.04.23.07.31.49 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 23 Apr 2024 07:31:50 -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: 39107441-017e-11ef-b4bb-af5377834399 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1713882710; x=1714487510; darn=lists.xenproject.org; h=content-transfer-encoding:in-reply-to:autocrypt:content-language :references:cc:to:from:subject:user-agent:mime-version:date :message-id:from:to:cc:subject:date:message-id:reply-to; bh=FaBzcTniCeLPDlfDE8HsE9EvmLilsBkel36WuSLRy1M=; b=EMgdggwI8sShHy3rL1SjS57lBu9RJhoiF6zZpgfo3MNB2EQM8co0hPqocMwRd+8hCS 1QdlqXCix91hVVxfMyzuBB55YCakidcxtznjGvh6Cjs3z+wdlV5NgtPUXJzTex4n7paC Gp7Qrrfroli3T6XIUrzLxi9V8PxbW3a2hLHCyA4QTBHj4b021KwykLvc8p9Ls7HXXKph pktl2fJTMBLfLYvZwp8e8xOT+culbWfaNLyGczG/4yI0qr70vh8PANsPj6PkotSqduZ7 vreo7kVpfxY/wK29D5nXubaHQD9sNj69n8anYxYRkVjecti4aIAM5VFoJAk1p0577xKV orEw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1713882710; x=1714487510; h=content-transfer-encoding:in-reply-to:autocrypt:content-language :references:cc:to:from:subject:user-agent:mime-version:date :message-id:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=FaBzcTniCeLPDlfDE8HsE9EvmLilsBkel36WuSLRy1M=; b=s84Tdh3kz60Rx3lgapDy21JuEvY0VI+A0mplcKFhsDDPgoMZ33zVpe7h53j1aggc6u I6E8UbdKjGr9zr634W3t969AYHcenkjidOeF3XStosEvB35fvxi/QqpXY10q1pWm2IiU z0VwxxNF7J6VDjCefamLWhEJe4OFVplsnrCxjE6hdkBRKSqxhjkwag9RxBWJX+PlVo44 hsXEWd2S46VqJtC7fdAYHVkUDzQfR91STBBZ+ZcYLs3p6MTYOg5tAn5JjekA9N4KJjAw J/TKdf/7haHh+Hk/pUF7kntAvkbhFH2y+PD+UaLaZcazoEs4z9Ny9qf1vdMoDQnMUc4M MmAA== X-Gm-Message-State: AOJu0YzsChhdwETx6nn4YeJ0/RYr3m+YdKUhG89FN5rOC3TCZNCBMI1/ NRPUjhnCbEhNGoBZxXE7V4QPpRVs02r5zAEeYKk6VnnoCYk3jvEdaf3p0UDfXk0XDGOk/r0Jiu8 = X-Google-Smtp-Source: AGHT+IHRxjmp9hzeoObXZyflT9qVP9fTo2B7EerM/xNB+brJvEXoz5INBRgPhKuzsbsmi66KqGHClQ== X-Received: by 2002:a05:600c:1c0f:b0:41a:c170:701f with SMTP id j15-20020a05600c1c0f00b0041ac170701fmr1633663wms.38.1713882710369; Tue, 23 Apr 2024 07:31:50 -0700 (PDT) Message-ID: <296c3ecc-b04d-4734-a451-0d4f9ed312d4@suse.com> Date: Tue, 23 Apr 2024 16:31:49 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: [PATCH 1/4] x86/P2M: write_p2m_entry() is HVM-only anyway From: Jan Beulich To: "xen-devel@lists.xenproject.org" Cc: Andrew Cooper , =?utf-8?q?Roger_Pau_Monn?= =?utf-8?q?=C3=A9?= , George Dunlap References: <0d846228-323b-4427-87d1-684c3d0047c5@suse.com> Content-Language: en-US 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: <0d846228-323b-4427-87d1-684c3d0047c5@suse.com> The latest as of e2b2ff677958 ("x86/P2M: split out init/teardown functions") the function is obviously unreachable for PV guests. Hence the paging_mode_enabled(d) check is pointless. Further host mode of a vCPU is always set, by virtue of paging_vcpu_init() being part of vCPU creation. Hence the paging_get_hostmode() check is pointless. With that the v local variable is unnecessary too. Drop the "if()" conditional and its corresponding "else". Signed-off-by: Jan Beulich --- I have to confess that this if() has been puzzling me before. --- a/xen/arch/x86/mm/p2m-pt.c +++ b/xen/arch/x86/mm/p2m-pt.c @@ -110,12 +110,7 @@ static int write_p2m_entry(struct p2m_do unsigned int level) { struct domain *d = p2m->domain; - const struct vcpu *v = current; - if ( v->domain != d ) - v = d->vcpu ? d->vcpu[0] : NULL; - if ( likely(v && paging_mode_enabled(d) && paging_get_hostmode(v)) || - p2m_is_nestedp2m(p2m) ) { unsigned int oflags; mfn_t omfn; @@ -156,8 +151,6 @@ static int write_p2m_entry(struct p2m_do !perms_strictly_increased(oflags, l1e_get_flags(new))) ) p2m_flush_nestedp2m(d); } - else - safe_write_pte(p, new); return 0; }