Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756042AbcCXQaX (ORCPT ); Thu, 24 Mar 2016 12:30:23 -0400 Received: from mail3-relais-sop.national.inria.fr ([192.134.164.104]:5842 "EHLO mail3-relais-sop.national.inria.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751834AbcCXQaS (ORCPT ); Thu, 24 Mar 2016 12:30:18 -0400 X-IronPort-AV: E=Sophos;i="5.24,385,1454972400"; d="scan'208";a="170652137" Date: Thu, 24 Mar 2016 17:30:10 +0100 (CET) From: Julia Lawall X-X-Sender: jll@hadrien To: Bartosz Golaszewski cc: Wolfram Sang , linux-i2c , LKML , Andrew Lunn , kbuild-all@01.org Subject: Re: [PATCH 04/13] eeprom: at24: make locking more fine-grained (fwd) Message-ID: User-Agent: Alpine 2.10 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6959 Lines: 98 If this is correct, it seems quite subtle. julia ---------- Forwarded message ---------- Date: Fri, 25 Mar 2016 00:25:33 +0800 From: kbuild test robot To: kbuild@01.org Cc: Julia Lawall Subject: Re: [PATCH 04/13] eeprom: at24: make locking more fine-grained CC: kbuild-all@01.org In-Reply-To: <1458830767-23816-5-git-send-email-bgolaszewski@baylibre.com> TO: Bartosz Golaszewski CC: Wolfram Sang , linux-i2c , LKML CC: Andrew Lunn , Bartosz Golaszewski Hi Bartosz, [auto build test WARNING on next-20160324] [cannot apply to v4.5-rc7 v4.5-rc6 v4.5-rc5 v4.5] [if your patch is applied to the wrong git tree, please drop us a note to help improving the system] url: https://github.com/0day-ci/linux/commits/Bartosz-Golaszewski/eeprom-support-for-at24cs-and-at24mac/20160324-230008 :::::: branch date: 85 minutes ago :::::: commit date: 85 minutes ago >> drivers/misc/eeprom/at24.c:356:3-9: preceding lock on line 312 git remote add linux-review https://github.com/0day-ci/linux git remote update linux-review git checkout 9e24d3f64066d8452c1ab00486a5a4878a30b7b1 vim +356 drivers/misc/eeprom/at24.c 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 306 if (!at24->use_smbus) { 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 307 int i = 0; 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 308 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 309 msg.addr = client->addr; 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 310 msg.flags = 0; 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 311 9e24d3f6 drivers/misc/eeprom/at24.c Bartosz Golaszewski 2016-03-24 @312 mutex_lock(&at24->wrbuf_lock); 9e24d3f6 drivers/misc/eeprom/at24.c Bartosz Golaszewski 2016-03-24 313 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 314 /* msg.buf is u8 and casts will mask the values */ 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 315 msg.buf = at24->writebuf; 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 316 if (at24->chip.flags & AT24_FLAG_ADDR16) 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 317 msg.buf[i++] = offset >> 8; 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 318 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 319 msg.buf[i++] = offset; 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 320 memcpy(&msg.buf[i], buf, count); 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 321 msg.len = i + count; 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 322 } 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 323 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 324 /* 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 325 * Writes fail if the previous one didn't complete yet. We may 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 326 * loop a few times until this one succeeds, waiting at least 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 327 * long enough for one entire page write to work. 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 328 */ 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 329 timeout = jiffies + msecs_to_jiffies(write_timeout); 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 330 do { 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 331 write_time = jiffies; a839ce66 drivers/misc/eeprom/at24.c Christian Gmeiner 2014-10-09 332 if (at24->use_smbus_write) { a839ce66 drivers/misc/eeprom/at24.c Christian Gmeiner 2014-10-09 333 switch (at24->use_smbus_write) { a839ce66 drivers/misc/eeprom/at24.c Christian Gmeiner 2014-10-09 334 case I2C_SMBUS_I2C_BLOCK_DATA: 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 335 status = i2c_smbus_write_i2c_block_data(client, 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 336 offset, count, buf); a839ce66 drivers/misc/eeprom/at24.c Christian Gmeiner 2014-10-09 337 break; a839ce66 drivers/misc/eeprom/at24.c Christian Gmeiner 2014-10-09 338 case I2C_SMBUS_BYTE_DATA: a839ce66 drivers/misc/eeprom/at24.c Christian Gmeiner 2014-10-09 339 status = i2c_smbus_write_byte_data(client, a839ce66 drivers/misc/eeprom/at24.c Christian Gmeiner 2014-10-09 340 offset, buf[0]); a839ce66 drivers/misc/eeprom/at24.c Christian Gmeiner 2014-10-09 341 break; a839ce66 drivers/misc/eeprom/at24.c Christian Gmeiner 2014-10-09 342 } a839ce66 drivers/misc/eeprom/at24.c Christian Gmeiner 2014-10-09 343 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 344 if (status == 0) 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 345 status = count; 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 346 } else { 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 347 status = i2c_transfer(client->adapter, &msg, 1); 9e24d3f6 drivers/misc/eeprom/at24.c Bartosz Golaszewski 2016-03-24 348 mutex_unlock(&at24->wrbuf_lock); 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 349 if (status == 1) 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 350 status = count; 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 351 } 2ce5b34f drivers/i2c/chips/at24.c David Brownell 2008-08-10 352 dev_dbg(&client->dev, "write %zu@%d --> %zd (%ld)\n", 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 353 count, offset, status, jiffies); 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 354 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 355 if (status == count) 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 @356 return count; 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 357 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 358 /* REVISIT: at HZ=100, this is sloooow */ 2b7a5056 drivers/i2c/chips/at24.c Wolfram Sang 2008-07-14 359 msleep(1); :::::: The code at line 356 was first introduced by commit :::::: 2b7a5056a0a7ff17d5d2004c29c852a92a6bd632 i2c: New-style EEPROM driver using device IDs :::::: TO: Wolfram Sang :::::: CC: Jean Delvare --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation