Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755344AbZIRTDi (ORCPT ); Fri, 18 Sep 2009 15:03:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754782AbZIRTDg (ORCPT ); Fri, 18 Sep 2009 15:03:36 -0400 Received: from pne-smtpout1-sn2.hy.skanova.net ([81.228.8.83]:36315 "EHLO pne-smtpout1-sn2.hy.skanova.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754526AbZIRTDf (ORCPT ); Fri, 18 Sep 2009 15:03:35 -0400 X-Greylist: delayed 4195 seconds by postgrey-1.27 at vger.kernel.org; Fri, 18 Sep 2009 15:03:35 EDT From: "Lars Ericsson" To: "'Frederik Deweerdt'" Cc: , , , "'Ivo van Doorn'" Subject: RE: Oops in drivers\base\firmware_class Date: Fri, 18 Sep 2009 19:53:40 +0200 Message-ID: <8A019019C4474E589B9EC14F451C0579@gotws1589> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Office Outlook 11 In-Reply-To: <20090916205717.GB12117@gambetta> Thread-Index: Aco3EGGamo7pXDJ9S/idVH/pF76lrgBd65uw X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7832 Lines: 201 > On Wed, Sep 16, 2009 at 08:44:43PM +0200, Lars Ericsson wrote: > > Hi, > > > > I have discovered a Oops in the firmware_loading_store function. > > At first it looks like a timing issue but after adding a > BUG_ON test, > > it fails every time. > > > > drivers\base\firmware_class: > > ------------------------------ > > 541 01c0 F6463401 testb $1,52(%esi) > > 542 01c4 0F843FFF je .L38 > > 542 FFFF > > 543 .loc 1 174 0 > > 544 01ca 8B4630 movl 48(%esi),%eax > > 545 01cd 8B4004 movl 4(%eax),%eax <---- Oops > > 546 01d0 E8FCFFFF call vfree > > 546 FF > > > > The code that fails was introduced in commit > > 6e03a201bbe8137487f340d26aa662110e324b20 > Could you try the following patch? No, problem. I have tried the patch and it works for me. I will continue my tests and report any problems. Should I close the http://bugzilla.kernel.org/show_bug.cgi?id=14185 , which I have created before I noticed you reply ? Thanks for the help ! /Lars > It seems that we're missing the locking around the accesses to > fw_priv->fw. > > Signed-off-by: Frederik Deweerdt > > diff --git a/drivers/base/firmware_class.c > b/drivers/base/firmware_class.c > index 8a267c4..49105ed 100644 > --- a/drivers/base/firmware_class.c > +++ b/drivers/base/firmware_class.c > @@ -171,12 +171,18 @@ static ssize_t > firmware_loading_store(struct device *dev, > break; > case 0: > if (test_bit(FW_STATUS_LOADING, &fw_priv->status)) { > + mutex_lock(&fw_lock); > + if (!fw_priv->fw) { > + mutex_unlock(&fw_lock); > + break; > + } > vfree(fw_priv->fw->data); > fw_priv->fw->data = vmap(fw_priv->pages, > fw_priv->nr_pages, > 0, PAGE_KERNEL_RO); > if (!fw_priv->fw->data) { > dev_err(dev, "%s: vmap() > failed\n", __func__); > + mutex_unlock(&fw_lock); > goto err; > } > /* Pages will be freed by vfree() */ > @@ -185,6 +191,7 @@ static ssize_t > firmware_loading_store(struct device *dev, > fw_priv->nr_pages = 0; > complete(&fw_priv->completion); > clear_bit(FW_STATUS_LOADING, &fw_priv->status); > + mutex_unlock(&fw_lock); > break; > } > /* fallthrough */ > > > > Attached you will find the: > > - Oops with the vanilla 2.6.31 > > - The BUG_ON patch > > - Oops with the patched 2.6.31 > > > > /Lars > > > [ 7.249453] rt61pci 0000:00:09.0: firmware: requesting > rt2561s.bin > > [ 7.314512] BUG: unable to handle kernel NULL pointer > dereference at 00000004 > > [ 7.315639] IP: [] > firmware_loading_store+0xed/0x160 [firmware_class] > > [ 7.315639] *pde = 00000000 > > [ 7.315639] Oops: 0000 [#1] PREEMPT > > [ 7.315639] last sysfs file: > /sys/devices/pci0000:00/0000:00:09.0/firmware/0000:00:09.0/loading > > [ 7.315639] Modules linked in: arc4 ecb cryptomgr > crypto_blkcipher aead pcompress crypto_hash crypto_algapi > rt61pci rt2x00pci rt2x00lib firmware_class mac80211 > input_polldev crc_itu_t eeprom_93cx6 cfg80211 ndccanram > ndccan ndcser(P) ndcscan(P) eu16550(P) ndccon(P) > > [ 7.315639] > > [ 7.315639] Pid: 1004, comm: echo Tainted: P > (2.6.31 #1) > > [ 7.315639] EIP: 0060:[] EFLAGS: 00010202 CPU: 0 > > [ 7.315639] EIP is at firmware_loading_store+0xed/0x160 > [firmware_class] > > [ 7.315639] EAX: 00000000 EBX: d04d50e0 ECX: 0000000a > EDX: 00000028 > > [ 7.315639] ESI: cf65ca80 EDI: cea29c00 EBP: cea29c08 > ESP: cf777f2c > > [ 7.315639] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 > > [ 7.315639] Process echo (pid: 1004, ti=cf776000 > task=cf755aa0 task.ti=cf776000) > > [ 7.315639] Stack: > > [ 7.315639] d04d50e0 cea29c00 00000002 c028051d > 00000002 c0414c40 ce9c0420 c01c9c98 > > [ 7.315639] <0> 00000002 c0414c40 00000002 b7f15000 > ce9c1e80 cf44c000 c01c9ce6 ce9c1e94 > > [ 7.315639] <0> cf44c000 b7f15000 00000002 c01c9cb0 > c018d362 cf777f9c cf44c000 fffffff7 > > [ 7.315639] Call Trace: > > [ 7.315639] [] ? > firmware_loading_store+0x0/0x160 [firmware_class] > > [ 7.315639] [] ? dev_attr_store+0x1d/0x20 > > [ 7.315639] [] ? flush_write_buffer+0x38/0x50 > > [ 7.315639] [] ? sysfs_write_file+0x36/0x60 > > [ 7.315639] [] ? sysfs_write_file+0x0/0x60 > > [ 7.315639] [] ? vfs_write+0x82/0xf0 > > [ 7.315639] [] ? sys_write+0x3c/0x70 > > [ 7.315639] [] ? syscall_call+0x7/0xb > > [ 7.315639] Code: 91 c9 ef 3b 5e 3c 7c ed eb b5 8d 74 26 > 00 83 f8 ff 0f 85 50 ff ff ff e9 6a ff ff ff 89 f6 f6 46 34 > 01 0f 84 3f ff ff ff 8b 46 30 <8b> 40 04 e8 5b 05 cb ef 31 c9 > 8b 56 3c 8b 46 38 8b 5e 30 68 61 > > [ 7.315639] EIP: [] > firmware_loading_store+0xed/0x160 [firmware_class] SS:ESP > 0068:cf777f2c > > [ 7.315639] CR2: 0000000000000004 > > [ 7.540848] ---[ end trace 6ebe83c102d3b046 ]--- > > > > [ 7.242449] ------------[ cut here ]------------ > > [ 7.243706] Kernel BUG at d04d523e [verbose debug info > unavailable] > > [ 7.243706] invalid opcode: 0000 [#1] PREEMPT > > [ 7.243706] last sysfs file: > /sys/devices/pci0000:00/0000:00:09.0/firmware/0000:00:09.0/loading > > [ 7.243706] Modules linked in: arc4 ecb cryptomgr > crypto_blkcipher aead pcompress crypto_hash crypto_algapi > rt61pci rt2x00pci rt2x00lib firmware_class mac80211 > input_polldev crc_itu_t eeprom_93cx6 cfg80211 ndccanram > ndccan ndcser(P) ndcscan(P) eu16550(P) ndccon(P) > > [ 7.243706] > > [ 7.243706] Pid: 1004, comm: echo Tainted: P > (2.6.31 #1) > > [ 7.243706] EIP: 0060:[] EFLAGS: 00010246 CPU: 0 > > [ 7.243706] EIP is at firmware_loading_store+0x15e/0x170 > [firmware_class] > > [ 7.243706] EAX: 00000000 EBX: d04d50e0 ECX: 0000000a > EDX: 00000028 > > [ 7.243706] ESI: cf4f2a20 EDI: cf4ffc00 EBP: cf4ffc08 > ESP: cea37f2c > > [ 7.243706] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 > > [ 7.243706] Process echo (pid: 1004, ti=cea36000 > task=cf6c2380 task.ti=cea36000) > > [ 7.243706] Stack: > > [ 7.243706] d04d50e0 cf4ffc00 00000002 c028051d > 00000002 c0414c40 cf4fd420 c01c9c98 > > [ 7.243706] <0> 00000002 c0414c40 00000002 b7fc8000 > cf636e80 cf471980 c01c9ce6 cf636e94 > > [ 7.243706] <0> cf471980 b7fc8000 00000002 c01c9cb0 > c018d362 cea37f9c cf471980 fffffff7 > > [ 7.243706] Call Trace: > > [ 7.243706] [] ? > firmware_loading_store+0x0/0x170 [firmware_class] > > [ 7.243706] [] ? dev_attr_store+0x1d/0x20 > > [ 7.243706] [] ? flush_write_buffer+0x38/0x50 > > [ 7.243706] [] ? sysfs_write_file+0x36/0x60 > > [ 7.243706] [] ? sysfs_write_file+0x0/0x60 > > [ 7.243706] [] ? vfs_write+0x82/0xf0 > > [ 7.243706] [] ? sys_write+0x3c/0x70 > > [ 7.243706] [] ? syscall_call+0x7/0xb > > [ 7.243706] Code: 66 34 fe e9 14 ff ff ff 8b 47 08 68 1c > 5f 4d d0 50 89 f8 e8 65 b2 da ef 50 68 c3 5f 4d d0 e8 da 3c > c5 ef 83 c4 10 e9 ea fe ff ff <0f> 0b eb fe 8d b4 26 00 00 00 > 00 8d bc 27 00 00 00 00 55 89 cd > > [ 7.243706] EIP: [] > firmware_loading_store+0x15e/0x170 [firmware_class] SS:ESP > 0068:cea37f2c > > [ 7.458557] ---[ end trace 604593037057054f ]--- > > -- > 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/ > -- 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/