Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756447Ab0LMA3w (ORCPT ); Sun, 12 Dec 2010 19:29:52 -0500 Received: from one.firstfloor.org ([213.235.205.2]:44707 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753736Ab0LLXpY (ORCPT ); Sun, 12 Dec 2010 18:45:24 -0500 From: Andi Kleen References: <201012131244.547034648@firstfloor.org> In-Reply-To: <201012131244.547034648@firstfloor.org> To: tilman@imap.cc, davem@davemloft.net, gregkh@suse.de, ak@linux.intel.com, linux-kernel@vger.kernel.org, stable@kernel.org Subject: [PATCH] [27/223] isdn/gigaset: fix bas_gigaset AT read error handling Message-Id: <20101212234523.47BE1B27C0@basil.firstfloor.org> Date: Mon, 13 Dec 2010 00:45:23 +0100 (CET) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4888 Lines: 163 2.6.35-longterm review patch. If anyone has any objections, please let me know. ------------------ From: Tilman Schmidt commit c8701a08d6a4efeae45d84d0aa87172f23b14e3c upstream. Rework the handling of USB errors in AT response reads to fix a possible infinite retry loop and a memory leak, and silence a few overly verbose kernel messages. Signed-off-by: Tilman Schmidt Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman Signed-off-by: Andi Kleen --- drivers/isdn/gigaset/bas-gigaset.c | 83 ++++++++++++++----------------------- 1 file changed, 33 insertions(+), 50 deletions(-) Index: linux/drivers/isdn/gigaset/bas-gigaset.c =================================================================== --- linux.orig/drivers/isdn/gigaset/bas-gigaset.c +++ linux/drivers/isdn/gigaset/bas-gigaset.c @@ -438,23 +438,27 @@ static void cmd_in_timeout(unsigned long return; } - if (ucs->retry_cmd_in++ < BAS_RETRY) { - dev_notice(cs->dev, "control read: timeout, retry %d\n", - ucs->retry_cmd_in); - rc = atread_submit(cs, BAS_TIMEOUT); - if (rc >= 0 || rc == -ENODEV) - /* resubmitted or disconnected */ - /* - bypass regular exit block */ - return; - } else { + if (ucs->retry_cmd_in++ >= BAS_RETRY) { dev_err(cs->dev, "control read: timeout, giving up after %d tries\n", ucs->retry_cmd_in); + kfree(ucs->rcvbuf); + ucs->rcvbuf = NULL; + ucs->rcvbuf_size = 0; + error_reset(cs); + return; + } + + gig_dbg(DEBUG_USBREQ, "%s: timeout, retry %d", + __func__, ucs->retry_cmd_in); + rc = atread_submit(cs, BAS_TIMEOUT); + if (rc < 0) { + kfree(ucs->rcvbuf); + ucs->rcvbuf = NULL; + ucs->rcvbuf_size = 0; + if (rc != -ENODEV) + error_reset(cs); } - kfree(ucs->rcvbuf); - ucs->rcvbuf = NULL; - ucs->rcvbuf_size = 0; - error_reset(cs); } /* read_ctrl_callback @@ -470,18 +474,11 @@ static void read_ctrl_callback(struct ur struct cardstate *cs = inbuf->cs; struct bas_cardstate *ucs = cs->hw.bas; int status = urb->status; - int have_data = 0; unsigned numbytes; int rc; update_basstate(ucs, 0, BS_ATRDPEND); wake_up(&ucs->waitqueue); - - if (!ucs->rcvbuf_size) { - dev_warn(cs->dev, "%s: no receive in progress\n", __func__); - return; - } - del_timer(&ucs->timer_cmd_in); switch (status) { @@ -495,19 +492,10 @@ static void read_ctrl_callback(struct ur numbytes = ucs->rcvbuf_size; } - /* copy received bytes to inbuf */ - have_data = gigaset_fill_inbuf(inbuf, ucs->rcvbuf, numbytes); - - if (unlikely(numbytes < ucs->rcvbuf_size)) { - /* incomplete - resubmit for remaining bytes */ - ucs->rcvbuf_size -= numbytes; - ucs->retry_cmd_in = 0; - rc = atread_submit(cs, BAS_TIMEOUT); - if (rc >= 0 || rc == -ENODEV) - /* resubmitted or disconnected */ - /* - bypass regular exit block */ - return; - error_reset(cs); + /* copy received bytes to inbuf, notify event layer */ + if (gigaset_fill_inbuf(inbuf, ucs->rcvbuf, numbytes)) { + gig_dbg(DEBUG_INTR, "%s-->BH", __func__); + gigaset_schedule_event(cs); } break; @@ -516,37 +504,32 @@ static void read_ctrl_callback(struct ur case -EINPROGRESS: /* pending */ case -ENODEV: /* device removed */ case -ESHUTDOWN: /* device shut down */ - /* no action necessary */ + /* no further action necessary */ gig_dbg(DEBUG_USBREQ, "%s: %s", __func__, get_usb_statmsg(status)); break; - default: /* severe trouble */ - dev_warn(cs->dev, "control read: %s\n", - get_usb_statmsg(status)); + default: /* other errors: retry */ if (ucs->retry_cmd_in++ < BAS_RETRY) { - dev_notice(cs->dev, "control read: retry %d\n", - ucs->retry_cmd_in); + gig_dbg(DEBUG_USBREQ, "%s: %s, retry %d", __func__, + get_usb_statmsg(status), ucs->retry_cmd_in); rc = atread_submit(cs, BAS_TIMEOUT); - if (rc >= 0 || rc == -ENODEV) - /* resubmitted or disconnected */ - /* - bypass regular exit block */ + if (rc >= 0) + /* successfully resubmitted, skip freeing */ return; - } else { - dev_err(cs->dev, - "control read: giving up after %d tries\n", - ucs->retry_cmd_in); + if (rc == -ENODEV) + /* disconnect, no further action necessary */ + break; } + dev_err(cs->dev, "control read: %s, giving up after %d tries\n", + get_usb_statmsg(status), ucs->retry_cmd_in); error_reset(cs); } + /* read finished, free buffer */ kfree(ucs->rcvbuf); ucs->rcvbuf = NULL; ucs->rcvbuf_size = 0; - if (have_data) { - gig_dbg(DEBUG_INTR, "%s-->BH", __func__); - gigaset_schedule_event(cs); - } } /* atread_submit -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/