From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760415AbbA1ENr (ORCPT ); Tue, 27 Jan 2015 23:13:47 -0500 Received: from mail.kernel.org ([198.145.29.136]:36719 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760375AbbA1ENo (ORCPT ); Tue, 27 Jan 2015 23:13:44 -0500 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Thomas Hellstrom , Zefan Li Subject: [PATCH 3.4 05/91] drm/vmwgfx: Fix a potential infinite spin waiting for fifo idle Date: Wed, 28 Jan 2015 12:06:17 +0800 Message-Id: <1422418236-12852-10-git-send-email-lizf@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1422418050-12581-1-git-send-email-lizf@kernel.org> References: <1422418050-12581-1-git-send-email-lizf@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thomas Hellstrom 3.4.105-rc1 review patch. If anyone has any objections, please let me know. ------------------ commit f01ea0c3d9db536c64d47922716d8b3b8f21d850 upstream. The code waiting for fifo idle was incorrect and could possibly spin forever under certain circumstances. Signed-off-by: Thomas Hellstrom Reported-by: Mark Sheldon Reviewed-by: Jakob Bornecrantz Reivewed-by: Mark Sheldon Signed-off-by: Zefan Li --- drivers/gpu/drm/vmwgfx/vmwgfx_fifo.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_fifo.c b/drivers/gpu/drm/vmwgfx/vmwgfx_fifo.c index a0c2f12..decca82 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_fifo.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_fifo.c @@ -163,8 +163,9 @@ void vmw_fifo_release(struct vmw_private *dev_priv, struct vmw_fifo_state *fifo) mutex_lock(&dev_priv->hw_mutex); + vmw_write(dev_priv, SVGA_REG_SYNC, SVGA_SYNC_GENERIC); while (vmw_read(dev_priv, SVGA_REG_BUSY) != 0) - vmw_write(dev_priv, SVGA_REG_SYNC, SVGA_SYNC_GENERIC); + ; dev_priv->last_read_seqno = ioread32(fifo_mem + SVGA_FIFO_FENCE); -- 1.9.1