From nobody Mon Feb 9 12:29:52 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 ARC-Seal: i=1; a=rsa-sha256; t=1770255401; cv=none; d=zohomail.com; s=zohoarc; b=M62o2hfh43Z8ysaNTGh4Red734Hgsj1ZJ0giVsD+WO2XjTE6ufzqypWUhML55dOuRXDKyDc1bxLxESRP1Og3GRxQ99UehtY3U5RZ4jQMInBsrm+JoJ6+sGFyPNcn8NyVFOn9WZtp0d+VQGM38i60b+ARpDhJysI47rhpA3gp4RU= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1770255401; h=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=bNWaJuUXW1hcVfeutPblFaJxcDIyBZhI3ZQ6lYZGoTo=; b=Ne43Hs8bdv9jFbcS1hZQxRtFYzE3EQJpO2RQLHfo0auftfd/GStK71qYwwJlldrfioLOeb4VWsp2Dq2nAPT63alGh+Yl8hFtFCgy7DEmFQgFwagagxy0JTFMlu3C45JUD8zZgSjffV8Ng683xAz4vWGTSAc4yMW3qkrPm1h5FhQ= 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 Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1770255401601119.53845509868336; Wed, 4 Feb 2026 17:36:41 -0800 (PST) Received: from list by lists.xenproject.org with outflank-mailman.1221356.1529658 (Exim 4.92) (envelope-from ) id 1vnoI9-0002ng-NS; Thu, 05 Feb 2026 01:36:21 +0000 Received: by outflank-mailman (output) from mailman id 1221356.1529658; Thu, 05 Feb 2026 01:36:21 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1vnoI9-0002mM-Hu; Thu, 05 Feb 2026 01:36:21 +0000 Received: by outflank-mailman (input) for mailman id 1221356; Thu, 05 Feb 2026 01:36:20 +0000 Received: from mail.xenproject.org ([104.130.215.37]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1vnoI8-0002cG-0K for xen-devel@lists.xenproject.org; Thu, 05 Feb 2026 01:36:20 +0000 Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.96) (envelope-from ) id 1vnoI7-003wRJ-33; Thu, 05 Feb 2026 01:36:19 +0000 Received: from [140.209.201.102] (helo=localhost) by xenbits.xenproject.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1vnoI7-00HVXb-1R; Thu, 05 Feb 2026 01:36:19 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version 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" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xen.org; s=20200302mail; h=Content-Transfer-Encoding:MIME-Version:References: In-Reply-To:Message-ID:Date:Subject:Cc:To:From; bh=bNWaJuUXW1hcVfeutPblFaJxcDIyBZhI3ZQ6lYZGoTo=; b=SVkMCn+PN2IcPts2W9aqfA74Q/ 3LhLaJthRaMLGDt5IMwKF9TsHjQWxQA7RlLRpqGUdCnP2GOxwcTbPJLIrxLIc2VA31I/9bsnqXfwA UDaUW6Ov1D2RETN8r6ef+r+kBXyRGddOfvmkexjwjkzLLeuL5XAIz5uOpY/KdZMYKOn8=; From: dmukhin@xen.org To: xen-devel@lists.xenproject.org Cc: andrew.cooper3@citrix.com, anthony.perard@vates.tech, jbeulich@suse.com, julien@xen.org, michal.orzel@amd.com, roger.pau@citrix.com, sstabellini@kernel.org, dmukhin@ford.com Subject: [PATCH v5 6/6] xen/console: add conring buffer size alignment setting Date: Wed, 4 Feb 2026 17:36:06 -0800 Message-ID: <20260205013606.3384798-7-dmukhin@ford.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260205013606.3384798-1-dmukhin@ford.com> References: <20260205013606.3384798-1-dmukhin@ford.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: pass (identity @xen.org) X-ZM-MESSAGEID: 1770255401817158500 Content-Type: text/plain; charset="utf-8" From: Denis Mukhin =20 Introduce CONFIG_CONRING_ALIGN_PAGE_SIZE to control rounding down of the user-defined conring buffer size. Also, update the logline reporting the final conring buffer size to report bytes instead of kilobytes, since the user-defined size may not necessarily be kilobyte-alined. Suggested-by: Andrew Cooper Signed-off-by: Denis Mukhin --- Changes since v4: - new patch --- xen/drivers/char/Kconfig | 7 +++++++ xen/drivers/char/console.c | 15 +++++++++------ 2 files changed, 16 insertions(+), 6 deletions(-) diff --git a/xen/drivers/char/Kconfig b/xen/drivers/char/Kconfig index d083ba4c9cdf..1b96fbc3ed7c 100644 --- a/xen/drivers/char/Kconfig +++ b/xen/drivers/char/Kconfig @@ -95,6 +95,13 @@ config SERIAL_TX_BUFSIZE =20 Default value is 32768 (32KiB). =20 +config CONRING_ALIGN_PAGE_SIZE + bool + default y + help + This selects the console ring buffer size alignment (rounding down) + to a multiple of PAGE_SIZE. + config CONRING_SHIFT int "Console ring buffer size (power of 2)" range 14 27 diff --git a/xen/drivers/char/console.c b/xen/drivers/char/console.c index 9394ab2a89eb..c13818715a52 100644 --- a/xen/drivers/char/console.c +++ b/xen/drivers/char/console.c @@ -470,12 +470,15 @@ void __init console_init_ring(void) return; =20 opt_conring_size =3D max(opt_conring_size, conring_size); - size =3D ROUNDDOWN(opt_conring_size, PAGE_SIZE); - if ( size !=3D opt_conring_size ) + if ( IS_ENABLED(CONFIG_CONRING_ALIGN_PAGE_SIZE) ) { - opt_conring_size =3D size; - printk(XENLOG_WARNING "Rounding down console ring size to multiple= of %lu KiB.\n", - PAGE_SIZE >> 10); + size =3D ROUNDDOWN(opt_conring_size, PAGE_SIZE); + if ( size !=3D opt_conring_size ) + { + opt_conring_size =3D size; + printk(XENLOG_WARNING "Rounding down console ring size to mult= iple of %lu KiB.\n", + PAGE_SIZE >> 10); + } } if ( opt_conring_size >=3D GB(2) ) { @@ -512,7 +515,7 @@ void __init console_init_ring(void) =20 nrspin_unlock_irqrestore(&console_lock, flags); =20 - printk("Allocated console ring of %u KiB.\n", opt_conring_size >> 10); + printk("Allocated console ring of %u bytes.\n", opt_conring_size); } =20 /* --=20 2.52.0