From patchwork Fri Jul 24 12:42:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Roger Pau Monne X-Patchwork-Id: 11683187 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4613F722 for ; Fri, 24 Jul 2020 12:43:35 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 201CD2074F for ; Fri, 24 Jul 2020 12:43:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=citrix.com header.i=@citrix.com header.b="deiS7u4X" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 201CD2074F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=citrix.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jyx2Q-000139-2f; Fri, 24 Jul 2020 12:42:58 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jyx2P-00012u-3k for xen-devel@lists.xenproject.org; Fri, 24 Jul 2020 12:42:57 +0000 X-Inumbo-ID: 308bff3e-cdab-11ea-880c-bc764e2007e4 Received: from esa4.hc3370-68.iphmx.com (unknown [216.71.155.144]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 308bff3e-cdab-11ea-880c-bc764e2007e4; Fri, 24 Jul 2020 12:42:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=citrix.com; s=securemail; t=1595594572; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=aDtTphrzz9VOwTJvjWtl31/5xlDEnj/EJHimWB6gA4o=; b=deiS7u4XhPpWcyrTBguRa/HFybY2oT+527j9v9hDZYTj5QajGP0eDFIf e1sQ+lNHIXbFlx2ROI87387Q4aePbqj0QV1UOdE2rXSEJC29D3E+/qB+1 GGH+UiStNhEGpK7mKKCNQCvRSRrUc6kDbgbeYrtTshSp8kPd6IczNqZH0 U=; Authentication-Results: esa4.hc3370-68.iphmx.com; dkim=none (message not signed) header.i=none IronPort-SDR: KJCsrxedNsP6PXR2GRxBdY4JBtMMaZKb/2iWqx70jsyhvQVs2mJ4a6ODJl6e5Ze0n71njR8l7V 9U+neT0HVYP3POae1Ostbc3PyXtJbBN2r4zxUF0cQs6LBnJFr0VNVu/tNCJc9T1E4naoIb331o PnI7RkHi0XdVA2g0geZOyiF6+NKoWClGj8G1fo1E2jxpTrVvVikRzuiGwbtXCIN56qO7yeEIjv kh6FrSOIHklNuDPUeb45cpzlQ/2JrbYLIt+iJwQswgcnxS7Z13OFRECZhFNlp6l07ZlfxwhxDd Xyk= X-SBRS: 2.7 X-MesageID: 23987140 X-Ironport-Server: esa4.hc3370-68.iphmx.com X-Remote-IP: 162.221.158.21 X-Policy: $RELAYED X-IronPort-AV: E=Sophos;i="5.75,390,1589256000"; d="scan'208";a="23987140" From: Roger Pau Monne To: Subject: [PATCH v2 1/4] xen/balloon: fix accounting in alloc_xenballooned_pages error path Date: Fri, 24 Jul 2020 14:42:38 +0200 Message-ID: <20200724124241.48208-2-roger.pau@citrix.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200724124241.48208-1-roger.pau@citrix.com> References: <20200724124241.48208-1-roger.pau@citrix.com> MIME-Version: 1.0 X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Juergen Gross , Stefano Stabellini , stable@vger.kernel.org, xen-devel@lists.xenproject.org, Boris Ostrovsky , Roger Pau Monne Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" target_unpopulated is incremented with nr_pages at the start of the function, but the call to free_xenballooned_pages will only subtract pgno number of pages, and thus the rest need to be subtracted before returning or else accounting will be skewed. Signed-off-by: Roger Pau Monné Cc: stable@vger.kernel.org Reviewed-by: Juergen Gross --- Cc: Boris Ostrovsky Cc: Juergen Gross Cc: Stefano Stabellini Cc: xen-devel@lists.xenproject.org --- drivers/xen/balloon.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c index 77c57568e5d7..3cb10ed32557 100644 --- a/drivers/xen/balloon.c +++ b/drivers/xen/balloon.c @@ -630,6 +630,12 @@ int alloc_xenballooned_pages(int nr_pages, struct page **pages) out_undo: mutex_unlock(&balloon_mutex); free_xenballooned_pages(pgno, pages); + /* + * NB: free_xenballooned_pages will only subtract pgno pages, but since + * target_unpopulated is incremented with nr_pages at the start we need + * to remove the remaining ones also, or accounting will be screwed. + */ + balloon_stats.target_unpopulated -= nr_pages - pgno; return ret; } EXPORT_SYMBOL(alloc_xenballooned_pages);