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Tue, 03 Feb 2026 08:49:37 -0800 (PST) Message-ID: Date: Tue, 3 Feb 2026 17:49:35 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: [PATCH 1/3] x86/shadow: unlock P2M slightly earlier in shadow_track_dirty_vram() From: Jan Beulich To: "xen-devel@lists.xenproject.org" Cc: Andrew Cooper , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= References: <5149ab32-7d03-4ae5-9af0-e62dd5836329@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: <5149ab32-7d03-4ae5-9af0-e62dd5836329@suse.com> Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: pass (identity @suse.com) X-ZM-MESSAGEID: 1770137403359154100 Content-Type: text/plain; charset="utf-8" There's no need to call vfree() with the lock still held. Signed-off-by: Jan Beulich --- In fact for the purposes of the function the P2M lock could really be obtained merely in read mode, and it could be dropped immediately in both the main "if()" and its "else if()". If only there wasn't the error handling after copy_to_guest(): Dropping the paging lock ahead of that call, we rely solely on the P2M lock to also guard the changing of d->arch.hvm.dirty_vram.sh and what it points to. Question is why dropping the paging lock (but continuing to hold the P2M lock) is necessary there in the first place. --- a/xen/arch/x86/mm/shadow/hvm.c +++ b/xen/arch/x86/mm/shadow/hvm.c @@ -1219,8 +1219,8 @@ int shadow_track_dirty_vram(struct domai paging_unlock(d); rc =3D -EFAULT; } - vfree(dirty_bitmap); p2m_unlock(p2m_get_hostp2m(d)); + vfree(dirty_bitmap); return rc; } From nobody Sat Feb 7 08:45:24 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=pass(p=quarantine dis=none) header.from=suse.com ARC-Seal: i=1; a=rsa-sha256; t=1770137416; cv=none; d=zohomail.com; s=zohoarc; b=e0Spv5PoYlzbGzLusquGZ74XoX6MhwiMwj+lXysSTI+vpE9P/9bnta7T20qw2I9HjQ9tQTqJp7IssM+zJ1Yh1rhpov6M1FU2roz8MrzWlRG3ZV72onmHRIx/z/iQnZgGkk4HWW4/huicCyatJhIdWYEmja/51GiLlXNZKwFeMxo= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1770137416; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=jSrVgJ47FbXZI7U0CKTH4UTDBJca7s7Dks5/LglLXeg=; b=b26qdOGkPh+9bQ3jvvPCBZgLQD5tNsyzCiaCohTi4J60RZD0bq/20cFGcVWQMxIX7BUgBRHuRFomGwbgKCNlNoBMEgVhvr4om38+OJ9SxGb1cI+5s1TuYklzJWVcjV+Lwau2b+7i0ayEe5X6fV5v4SJNeLU87qEe8c+Jt1Cce8s= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=pass header.from= (p=quarantine dis=none) Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1770137416641550.3817255344964; Tue, 3 Feb 2026 08:50:16 -0800 (PST) Received: from list by lists.xenproject.org with outflank-mailman.1219421.1528301 (Exim 4.92) (envelope-from ) id 1vnJbF-0005AG-Pi; Tue, 03 Feb 2026 16:50:01 +0000 Received: by outflank-mailman (output) from mailman id 1219421.1528301; Tue, 03 Feb 2026 16:50:01 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1vnJbF-00059k-N9; Tue, 03 Feb 2026 16:50:01 +0000 Received: by outflank-mailman (input) for mailman id 1219421; Tue, 03 Feb 2026 16:49:59 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1vnJbD-0004jK-Oq for xen-devel@lists.xenproject.org; Tue, 03 Feb 2026 16:49:59 +0000 Received: from mail-wr1-x42d.google.com (mail-wr1-x42d.google.com [2a00:1450:4864:20::42d]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 5f6c0bc4-0120-11f1-9ccf-f158ae23cfc8; Tue, 03 Feb 2026 17:49:57 +0100 (CET) Received: by mail-wr1-x42d.google.com with SMTP id ffacd0b85a97d-435a517be33so3521246f8f.0 for ; Tue, 03 Feb 2026 08:49:57 -0800 (PST) Received: from [10.156.60.236] (ip-037-024-206-209.um08.pools.vodafone-ip.de. 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Tue, 03 Feb 2026 08:49:57 -0800 (PST) Message-ID: <8559db88-5f1d-4ced-980c-e71c4e229c7c@suse.com> Date: Tue, 3 Feb 2026 17:49:55 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: [PATCH 2/3] x86/shadow: VRAM last_dirty tagging From: Jan Beulich To: "xen-devel@lists.xenproject.org" Cc: Andrew Cooper , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= References: <5149ab32-7d03-4ae5-9af0-e62dd5836329@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: <5149ab32-7d03-4ae5-9af0-e62dd5836329@suse.com> Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: pass (identity @suse.com) X-ZM-MESSAGEID: 1770137418876158500 Content-Type: text/plain; charset="utf-8" ->last_dirty holding a valid value (one other than -1) is solely an indication of the bitmap being entirely clean. (The opposite isn't true, because of _sh_propagate() setting the field to a valid value without setting a bit in the bitmap.) As a consequence - setting the field to a valid value right after having allocated zero- filled space is pointless, - copying the the all empty bitmap to the output array is pointless; with the output array also having been allocated zero-filled, not even a memset() is needed there, - after restoring bitmap contents when dealing with copy_to_guest() having failed, the field needs setting to a valid value again. Furthermore invoking NOW() in perhaps many loop iterations of the main loop is wasteful, too. Record whether any bit was set, and record a new ->last_dirty only once, after the loop. Then use the same NOW() value also for the subsequent check. Signed-off-by: Jan Beulich --- a/xen/arch/x86/mm/shadow/hvm.c +++ b/xen/arch/x86/mm/shadow/hvm.c @@ -1087,18 +1087,18 @@ int shadow_track_dirty_vram(struct domai if ( (dirty_vram->dirty_bitmap =3D xzalloc_array(uint8_t, dirty_si= ze)) =3D=3D NULL ) goto out_sl1ma; =20 - dirty_vram->last_dirty =3D NOW(); + dirty_vram->last_dirty =3D -1; =20 /* Tell the caller that this time we could not track dirty bits. */ rc =3D -ENODATA; } - else if ( dirty_vram->last_dirty =3D=3D -1 ) - /* still completely clean, just copy our empty bitmap */ - memcpy(dirty_bitmap, dirty_vram->dirty_bitmap, dirty_size); - else + /* Nothing to do when the bitmap is still completely clean. */ + else if ( dirty_vram->last_dirty !=3D -1 ) { mfn_t map_mfn =3D INVALID_MFN; void *map_sl1p =3D NULL; + bool any_dirty =3D false; + s_time_t now; =20 /* Iterate over VRAM to track dirty bits. */ for ( i =3D 0; i < nr_frames; i++ ) @@ -1174,16 +1174,20 @@ int shadow_track_dirty_vram(struct domai if ( dirty ) { dirty_vram->dirty_bitmap[i / 8] |=3D 1 << (i % 8); - dirty_vram->last_dirty =3D NOW(); + any_dirty =3D true; } } =20 + now =3D NOW(); + if ( any_dirty ) + dirty_vram->last_dirty =3D now; + if ( map_sl1p ) unmap_domain_page(map_sl1p); =20 memcpy(dirty_bitmap, dirty_vram->dirty_bitmap, dirty_size); memset(dirty_vram->dirty_bitmap, 0, dirty_size); - if ( dirty_vram->last_dirty + SECONDS(2) < NOW() ) + if ( dirty_vram->last_dirty + SECONDS(2) < now ) { /* * Was clean for more than two seconds, try to disable guest @@ -1216,6 +1220,7 @@ int shadow_track_dirty_vram(struct domai paging_lock(d); for ( i =3D 0; i < dirty_size; i++ ) dirty_vram->dirty_bitmap[i] |=3D dirty_bitmap[i]; + dirty_vram->last_dirty =3D NOW(); paging_unlock(d); rc =3D -EFAULT; } From nobody Sat Feb 7 08:45:24 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=pass(p=quarantine dis=none) header.from=suse.com ARC-Seal: i=1; a=rsa-sha256; t=1770137448; cv=none; d=zohomail.com; s=zohoarc; b=bJ2c7/j0J8+Cg0b3XM0v2Sbc5/e/YMtt2bqI3vYoebVdVugNCMBEnuQlvbxm1738cv+Rb2KTqFyOp0GseDhIYVd/las+SMcnI2ST6fl8ofGGml7epcTbPTCjVUyvnYZt5/iLaUl3VD6xZvX/Ea0G2I5YzYirrcF9ij68KpCXWL4= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1770137448; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=ArrlHuUWuRHWGJM3SpePVZfqjLgEGNYvg8IJ6jwvR5M=; b=nH0Gjj+YdMDNNK1sZZo+nLkpZX5WI97G9rPWiWf6L0WtvqTkL2I2nf1+a3cuJF/jmSCVSbRVKj4BbW9M2UnnshHr1s5puQtNlJgOYXvg9zZF5xdR9WONubhOiuI1Uj2M1jM9NH7P++mCCFhrpTKyGG5ZI17nDKf5CsJrTmrBqQc= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=pass header.from= (p=quarantine dis=none) Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1770137448962423.10732928267237; Tue, 3 Feb 2026 08:50:48 -0800 (PST) Received: from list by lists.xenproject.org with outflank-mailman.1219426.1528312 (Exim 4.92) (envelope-from ) id 1vnJbp-0006bm-2U; Tue, 03 Feb 2026 16:50:37 +0000 Received: by outflank-mailman (output) from mailman id 1219426.1528312; Tue, 03 Feb 2026 16:50:37 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1vnJbo-0006bf-Vr; Tue, 03 Feb 2026 16:50:36 +0000 Received: by outflank-mailman (input) for mailman id 1219426; Tue, 03 Feb 2026 16:50:36 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1vnJbo-0006bJ-0k for xen-devel@lists.xenproject.org; Tue, 03 Feb 2026 16:50:36 +0000 Received: from mail-wm1-x330.google.com (mail-wm1-x330.google.com [2a00:1450:4864:20::330]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 74e040b3-0120-11f1-9ccf-f158ae23cfc8; Tue, 03 Feb 2026 17:50:33 +0100 (CET) Received: by mail-wm1-x330.google.com with SMTP id 5b1f17b1804b1-4801ea9bafdso26650015e9.3 for ; Tue, 03 Feb 2026 08:50:33 -0800 (PST) Received: from [10.156.60.236] (ip-037-024-206-209.um08.pools.vodafone-ip.de. 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Tue, 03 Feb 2026 08:50:33 -0800 (PST) Message-ID: <38581c16-e2a0-4f7e-a08a-3517063a27cc@suse.com> Date: Tue, 3 Feb 2026 17:50:31 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: [PATCH 3/3] x86/shadow: reduce flush_tlb's scope in shadow_track_dirty_vram() From: Jan Beulich To: "xen-devel@lists.xenproject.org" Cc: Andrew Cooper , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= References: <5149ab32-7d03-4ae5-9af0-e62dd5836329@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: <5149ab32-7d03-4ae5-9af0-e62dd5836329@suse.com> Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: pass (identity @suse.com) X-ZM-MESSAGEID: 1770137449889154100 Content-Type: text/plain; charset="utf-8" It's set only in the main "else", so the declaration as well as the sole consumer can also move into that more narrow scope. This may in particular help with possible future locking changes. Signed-off-by: Jan Beulich --- a/xen/arch/x86/mm/shadow/hvm.c +++ b/xen/arch/x86/mm/shadow/hvm.c @@ -1022,7 +1022,6 @@ int shadow_track_dirty_vram(struct domai int rc =3D 0; unsigned long end_pfn =3D begin_pfn + nr_frames; unsigned int dirty_size =3D DIV_ROUND_UP(nr_frames, BITS_PER_BYTE); - int flush_tlb =3D 0; unsigned long i; p2m_type_t t; struct sh_dirty_vram *dirty_vram; @@ -1097,7 +1096,7 @@ int shadow_track_dirty_vram(struct domai { mfn_t map_mfn =3D INVALID_MFN; void *map_sl1p =3D NULL; - bool any_dirty =3D false; + bool any_dirty =3D false, flush_tlb =3D false; s_time_t now; =20 /* Iterate over VRAM to track dirty bits. */ @@ -1158,7 +1157,7 @@ int shadow_track_dirty_vram(struct domai * _PAGE_ACCESSED set by another processor. */ l1e_remove_flags(*sl1e, _PAGE_DIRTY); - flush_tlb =3D 1; + flush_tlb =3D true; } } break; @@ -1201,9 +1200,10 @@ int shadow_track_dirty_vram(struct domai } dirty_vram->last_dirty =3D -1; } + + if ( flush_tlb ) + guest_flush_tlb_mask(d, d->dirty_cpumask); } - if ( flush_tlb ) - guest_flush_tlb_mask(d, d->dirty_cpumask); goto out; =20 out_sl1ma: