From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755648AbdKGBKe (ORCPT ); Mon, 6 Nov 2017 20:10:34 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:52540 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755243AbdKFXyJ (ORCPT ); Mon, 6 Nov 2017 18:54:09 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Arnd Bergmann" , "David S. Miller" Date: Mon, 06 Nov 2017 23:03:02 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 246/294] mISDN: avoid arch specific __builtin_return_address call In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.50-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Arnd Bergmann commit 3e7a8716e20b759eec0ad88145255bb33174f0c8 upstream. Not all architectures are able to call __builtin_return_address(). On ARM, the mISDN code produces this warning: hardware/mISDN/w6692.c: In function 'w6692_dctrl': hardware/mISDN/w6692.c:1181:75: warning: unsupported argument to '__builtin_return_address' pr_debug("%s: %s dev(%d) open from %p\n", card->name, __func__, ^ hardware/mISDN/mISDNipac.c: In function 'open_dchannel': hardware/mISDN/mISDNipac.c:759:75: warning: unsupported argument to '__builtin_return_address' pr_debug("%s: %s dev(%d) open from %p\n", isac->name, __func__, ^ In a lot of cases, this is relatively easy to work around by passing the value of __builtin_return_address(0) from the callers into the functions that want it. One exception is the indirect 'open' function call in struct isac_hw. While it would be possible to fix this as well, this patch only addresses the other callers properly and lets this one return the direct parent function, which should be good enough. Signed-off-by: Arnd Bergmann Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- drivers/isdn/hardware/mISDN/mISDNipac.c | 12 +++++++++--- drivers/isdn/hardware/mISDN/w6692.c | 6 +++--- 2 files changed, 12 insertions(+), 6 deletions(-) --- a/drivers/isdn/hardware/mISDN/mISDNipac.c +++ b/drivers/isdn/hardware/mISDN/mISDNipac.c @@ -754,10 +754,10 @@ dbusy_timer_handler(struct isac_hw *isac } static int -open_dchannel(struct isac_hw *isac, struct channel_req *rq) +open_dchannel_caller(struct isac_hw *isac, struct channel_req *rq, void *caller) { pr_debug("%s: %s dev(%d) open from %p\n", isac->name, __func__, - isac->dch.dev.id, __builtin_return_address(1)); + isac->dch.dev.id, caller); if (rq->protocol != ISDN_P_TE_S0) return -EINVAL; if (rq->adr.channel == 1) @@ -771,6 +771,12 @@ open_dchannel(struct isac_hw *isac, stru return 0; } +static int +open_dchannel(struct isac_hw *isac, struct channel_req *rq) +{ + return open_dchannel_caller(isac, rq, __builtin_return_address(0)); +} + static const char *ISACVer[] = {"2086/2186 V1.1", "2085 B1", "2085 B2", "2085 V2.3"}; @@ -1547,7 +1553,7 @@ ipac_dctrl(struct mISDNchannel *ch, u32 case OPEN_CHANNEL: rq = arg; if (rq->protocol == ISDN_P_TE_S0) - err = open_dchannel(isac, rq); + err = open_dchannel_caller(isac, rq, __builtin_return_address(0)); else err = open_bchannel(ipac, rq); if (err) --- a/drivers/isdn/hardware/mISDN/w6692.c +++ b/drivers/isdn/hardware/mISDN/w6692.c @@ -1176,10 +1176,10 @@ w6692_l1callback(struct dchannel *dch, u } static int -open_dchannel(struct w6692_hw *card, struct channel_req *rq) +open_dchannel(struct w6692_hw *card, struct channel_req *rq, void *caller) { pr_debug("%s: %s dev(%d) open from %p\n", card->name, __func__, - card->dch.dev.id, __builtin_return_address(1)); + card->dch.dev.id, caller); if (rq->protocol != ISDN_P_TE_S0) return -EINVAL; if (rq->adr.channel == 1) @@ -1207,7 +1207,7 @@ w6692_dctrl(struct mISDNchannel *ch, u32 case OPEN_CHANNEL: rq = arg; if (rq->protocol == ISDN_P_TE_S0) - err = open_dchannel(card, rq); + err = open_dchannel(card, rq, __builtin_return_address(0)); else err = open_bchannel(card, rq); if (err)