From patchwork Mon Apr 10 17:44:30 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sumit Semwal X-Patchwork-Id: 97212 Delivered-To: patch@linaro.org Received: by 10.182.246.10 with SMTP id xs10csp1456543obc; Mon, 10 Apr 2017 10:46:04 -0700 (PDT) X-Received: by 10.99.125.12 with SMTP id y12mr7328491pgc.146.1491846364045; Mon, 10 Apr 2017 10:46:04 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id w21si14197944pgh.90.2017.04.10.10.46.03; Mon, 10 Apr 2017 10:46:04 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of stable-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@linaro.org; spf=pass (google.com: best guess record for domain of stable-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754077AbdDJRqB (ORCPT + 5 others); Mon, 10 Apr 2017 13:46:01 -0400 Received: from mail-pg0-f51.google.com ([74.125.83.51]:35045 "EHLO mail-pg0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754010AbdDJRqA (ORCPT ); Mon, 10 Apr 2017 13:46:00 -0400 Received: by mail-pg0-f51.google.com with SMTP id 81so109370983pgh.2 for ; Mon, 10 Apr 2017 10:45:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=b/4EdhaVvM16veNbBlzw6pKOeSID24uDb6DOWoRvntM=; b=PheRkK8rDXK4a8si1Mhf3UFu/BfP3vqac3rk2CgaoFoj2aSOFjvmMVL/oSoe9qXqCW LU6G32+qQAorn3eaYQk9eBvYYPf1jabhNvysIXPLgcKmv5xrjy8JdXlNGqDyeC13T3Ze jAydDCl577OsgdNVeecECJpCSRybH1DqF6T7E= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=b/4EdhaVvM16veNbBlzw6pKOeSID24uDb6DOWoRvntM=; b=lMT2a8b9x+lAveBFo6QBIQry6ul1dam3niZbtZOxKwph4rN1BAlotrYfOL724i9Jn9 XSsBqeSGHKqoZgGFSbYGjbyFv1jnprDGN7OWkKiIMTnBVwtOtQ+YoxSXxGEGHXktULxf s0NUozxR3fjuJhBWaUtq4vDycroOuZmZ63WacZdzWAGzH6wRNf2lT7rrwb6KZ1Ekm7TF vjojLf+N0FfvcWelojg+ef3N0Pm9j3uHs1Fxl7YEOq7DPx4JiXNv227ByGckiGqVoUbS PblO5C5pULTBDGiiS6PyFsRfY+h5Wgu/PCVmddWuEOd9k9r4bWYlIOVc4iJMyCv4zb7b wetA== X-Gm-Message-State: AFeK/H3GlQPBzoirNT/vi55PwOCYxHEHa2Arx6L3HoH1OLLzOg+PAS0epgUXBkmFbufkTWCi X-Received: by 10.98.219.3 with SMTP id f3mr54626223pfg.181.1491846349343; Mon, 10 Apr 2017 10:45:49 -0700 (PDT) Received: from phantom.lan ([106.51.225.38]) by smtp.gmail.com with ESMTPSA id y6sm768833pfa.83.2017.04.10.10.45.46 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 10 Apr 2017 10:45:48 -0700 (PDT) From: Sumit Semwal To: stable@vger.kernel.org Cc: Vitaly Kuznetsov , "K . Y . Srinivasan" , Greg Kroah-Hartman , Sumit Semwal Subject: [PATCH for-4.4 14/16] hv: don't reset hv_context.tsc_page on crash Date: Mon, 10 Apr 2017 23:14:30 +0530 Message-Id: <1491846272-14882-15-git-send-email-sumit.semwal@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1491846272-14882-1-git-send-email-sumit.semwal@linaro.org> References: <1491846272-14882-1-git-send-email-sumit.semwal@linaro.org> Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vitaly Kuznetsov [ Upstream commit 56ef6718a1d8d77745033c5291e025ce18504159 ] It may happen that secondary CPUs are still alive and resetting hv_context.tsc_page will cause a consequent crash in read_hv_clock_tsc() as we don't check for it being not NULL there. It is safe as we're not freeing this page anyways. Signed-off-by: Vitaly Kuznetsov Signed-off-by: K. Y. Srinivasan Cc: Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sumit Semwal --- drivers/hv/hv.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) -- 2.7.4 diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c index ddbf7e7..8ce1f2e 100644 --- a/drivers/hv/hv.c +++ b/drivers/hv/hv.c @@ -305,9 +305,10 @@ void hv_cleanup(bool crash) hypercall_msr.as_uint64 = 0; wrmsrl(HV_X64_MSR_REFERENCE_TSC, hypercall_msr.as_uint64); - if (!crash) + if (!crash) { vfree(hv_context.tsc_page); - hv_context.tsc_page = NULL; + hv_context.tsc_page = NULL; + } } #endif }