October 2010 - Darwin-kernel

Re: Darwin-kernel Digest, Vol 7, Issue 142
by DanielV. 27 Oct '10

27 Oct '10

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Re: Kernel Panic From Storage Problem?
by Shantonu Sen 26 Oct '10

26 Oct '10

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Re: Kernel Panic From Storage Problem?
by Michael Smith 26 Oct '10

26 Oct '10

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Kernel Panic From Storage Problem?
by George Plymale 25 Oct '10

25 Oct '10

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Seems that I have my fair share of hard drives failing and I am wondering your take on the following panic in terms of, to my eyes, appearing to be resultant from something going on with a drive failing due to bad blocks (FS structure appears to check out okay). This panic has recurred several times over the last week: Interval Since Last Panic Report: 129611 sec Panics Since Last Report: 1 Anonymous UUID: 852B0371-2211-4D84-82DC-69791532D2B8 Mon Oct 25 15:23:34 2010 panic(cpu 4 caller 0xffffff80002cf17f): Double fault thread:0xffffff802fb1e260 at 0xffffff80002ad6a8, registers: CR0: 0x000000008001003b, CR2: 0xffffff80fefaff98, CR3: 0x000000016e38e000, CR4: 0x0000000000000660 RAX: 0x0000000000000000, RBX: 0x0000000000001400, RCX: 0x0000000000001000, RDX: 0x0000000000001000 RSP: 0xffffff80fefaffa0, RBP: 0xffffff80fefb0340, RSI: 0x0000000000000200, RDI: 0x0000000000000002 R8: 0xffffff802f43b098, R9: 0xffffff80fefb0688, R10: 0x0000000000000064, R11: 0x0000000000000000 R12: 0x0000000000001000, R13: 0xffffff80006a8260, R14: 0x0000000000001000, R15: 0xffffff8028fdd000 RFL: 0x0000000000010246, RIP: 0xffffff80002ad6a8, CS: 0x0000000000000008, SS: 0x0000000000000010 Error code: 0x0000000000000000 Backtrace (CPU 4), Frame : Return Address 0xffffff80d1e0eeb0 : 0xffffff8000204b99 0xffffff80d1e0efb0 : 0xffffff80002cf17f 0xffffff80d1e0f0a0 : 0xffffff80002e29ef 0xffffff80fefb0340 : 0xffffff80002ae7a1 0xffffff80fefb0470 : 0xffffff80002ae5eb 0xffffff80fefb05a0 : 0xffffff800053dbf8 0xffffff80fefb06c0 : 0xffffff800053df61 0xffffff80fefb06f0 : 0xffffff7f806870f3 0xffffff80fefb07a0 : 0xffffff8000315622 0xffffff80fefb0800 : 0xffffff80002eb23a 0xffffff80fefb08c0 : 0xffffff800030a7ce 0xffffff80fefb08f0 : 0xffffff80002ecc45 0xffffff80fefb0920 : 0xffffff80002eccac 0xffffff80fefb0940 : 0xffffff800041931c 0xffffff80fefb09b0 : 0xffffff800044b61d 0xffffff80fefb09d0 : 0xffffff800044d5e8 0xffffff80fefb0ac0 : 0xffffff8000449edd 0xffffff80fefb0be0 : 0xffffff800044ef07 0xffffff80fefb0ef0 : 0xffffff800044fb15 0xffffff80fefb0f60 : 0xffffff800044fca0 0xffffff80fefb1030 : 0xffffff800042bb70 0xffffff80fefb10c0 : 0xffffff800030bcc1 0xffffff80fefb1160 : 0xffffff80002eec31 0xffffff80fefb12c0 : 0xffffff80002efffe 0xffffff80fefb1340 : 0xffffff80002f0039 0xffffff80fefb1370 : 0xffffff800042b753 0xffffff80fefb13f0 : 0xffffff800030a574 0xffffff80fefb1440 : 0xffffff80004c3232 0xffffff80fefb14e0 : 0xffffff800026242c 0xffffff80fefb18c0 : 0xffffff8000264e32 0xffffff80fefb1910 : 0xffffff8000212e4b 0xffffff80fefb19f0 : 0xffffff80002ada4f Backtrace continues... Kernel Extensions in backtrace (with dependencies): com.apple.iokit.IOStorageFamily(1.6.2)@0xffffff7f80679000->0xffffff7f80692fff BSD process name corresponding to current thread: Path Finder Mac OS version: 10H562 Kernel version: Darwin Kernel Version 10.5.0: Wed Sep 29 15:10:36 PDT 2010; root:xnu-1504.9.16~1/RELEASE_X86_64 System model name: MacPro3,1 (Mac-F42C88C8) System uptime in nanoseconds: 146690505800359 unloaded kexts: (none) loaded kexts: com.binaryage.totalfinder.kext 1.0 - last l Model: MacPro3,1, BootROM MP31.006C.B05, 8 processors, Quad-Core Intel Xeon, 3 GHz, 10 GB, SMC 1.25f4 Graphics: ATI Radeon HD 2600 XT, ATI Radeon HD 2600, PCIe, 256 MB Graphics: ATI Radeon HD 4870, ATI Radeon HD 4870, PCIe, 512 MB Memory Module: global_name Bluetooth: Version 2.3.8f7, 2 service, 19 devices, 1 incoming serial ports Network Service: Ethernet 1, Ethernet, en0 PCI Card: ATI Radeon HD 2600, Display, Slot-3 PCI Card: ATI Radeon HD 4870, Display, Slot-1 Serial ATA Device: WDC WD20EADS-00R6B0, 1.82 TB Serial ATA Device: WDC WD20EADS-00R6B0, 1.82 TB Serial ATA Device: WDC WD3000HLFS-01G6U0, 279.46 GB Serial ATA Device: WDC WD3000HLFS-01G6U0, 279.46 GB Parallel ATA Device: PIONEER DVD-RW DVR-112D USB Device: Hub, 0x05ac (Apple Inc.), 0x9120, 0xfd400000 USB Device: Miscellaneous Device, 0x046d (Logitech Inc.), 0x0809, 0xfd410000 USB Device: Hub, 0x0424 (SMSC), 0x2512, 0xfd420000 USB Device: Hub, 0x0424 (SMSC), 0x2602, 0xfd421000 USB Device: Microsoft Trackball Explorer®, 0x045e (Microsoft Corporation), 0x0024, 0xfd421300 USB Device: Flash Card Reader, 0x0424 (SMSC), 0x2228, 0xfd421100 USB Device: Apple Cinema HD Display, 0x05ac (Apple Inc.), 0x9220, 0xfd430000 USB Device: Keyboard Hub, 0x05ac (Apple Inc.), 0x1006, 0xfd500000 USB Device: Apple Keyboard, 0x05ac (Apple Inc.), 0x0220, 0xfd520000 USB Device: Hub, 0x050d (Belkin Corporation), 0x0237, 0xfd300000 USB Device: Deskjet F4400 series, 0x03f0 (Hewlett Packard), 0x7711, 0xfd360000 USB Device: CTH-661, 0x056a (WACOM Co., Ltd.), 0x00d3, 0xfd370000 USB Device: iPhone, 0x05ac (Apple Inc.), 0x1294, 0xfd320000 USB Device: C-Media USB Headphone Set, 0x0d8c (C-MEDIA ELECTRONICS INC.), 0x000c, 0xfd310000 USB Device: Bluetooth USB Host Controller, 0x05ac (Apple Inc.), 0x8206, 0x5d200000 FireWire Device: built-in_hub, Up to 800 Mb/sec FireWire Device: Rev2, Drobo, Up to 800 Mb/sec FireWire Device: unknown_device, Unknown _______________________________________________ Do not post admin requests to the list. 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IOSharedDataQueue sample code.
by tech＠macinapp.com 22 Oct '10

22 Oct '10

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Domainkey-signature: a=rsa-sha1; q=dns; c=nofws; s=default; d=macinapp.com; h=Received:Message-ID:Date:From:User-Agent:MIME-Version:To:Subject:Content-Type:Content-Transfer-Encoding:X-Identified-User; b=QrKai9skf7nlP2SsJZdjxc7lCBGJFKD51PvwqqBuIu3X27HPS2hDlK4FEYBSnt+z08pivtWvIpjSx5H1q/yOUX76mYeSzdL/jfUJJYN2ji6pmUR4MK8Gm4++BUOYTkXs; User-agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; ru; rv:1.9.2.11) Gecko/20101013 Thunderbird/3.1.5 Thanks. _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… Where can i found sample code for using IOSharedDataQueue ( i want to send data from user-space to kernel-space)? This email sent to site_archiver(a)lists.apple.com

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Re: How to reach owner SWITCHING but no waiters in 10.5.8 pthread_mutex_lock?
by Chris Suter 22 Oct '10

22 Oct '10

site_archiver(a)lists.apple.com Delivered-To: Darwin-kernel(a)lists.apple.com On Fri, Oct 22, 2010 at 3:17 PM, Jeremy W. Sherman <jeremyw.sherman(a)gmail.com> wrote: > I was reading through the 10.5.8 pthread mutex implementation > (Libc-498.1.7/xnu-1228.15.4). I am stumped by a couple things, and I > hope that someone here can shed some light on them. > > > First: How might a thread enter this else-if clause in > pthread_mutex_lock() (Libc/pthreads/pthread_mutex.c:333)? Possibly because of pthread_cond_wait. It sets the owner to PTHREAD_MUTEX_OWNER_SWITCHING at one point. -- Chris _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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How to reach owner SWITCHING but no waiters in 10.5.8 pthread_mutex_lock?
by Jeremy W. Sherman 22 Oct '10

22 Oct '10

site_archiver(a)lists.apple.com Delivered-To: Darwin-kernel(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:mime-version:received:from:date :message-id:subject:to:content-type:content-transfer-encoding; bh=gqlVlAenaa0UKE9UivMfQz8ZD2K6JqHVJVKcFaQSWh4=; b=H5ainNh4PJ8Kcs4e2uYl2tt4AnwyUBrYGoDOtW4hPYH2l37dkcnZfKWo+jMx14rV0+ Q8fD4OKDSClpOgOs9fxzBisPa+pfTBaAgr7Qb5U5H5eoJshh+vIEyfI2QWLXFr6tsbvv AbmC8ci8m8oeP/klsUDMZctITt9sNIkO+Mems= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:from:date:message-id:subject:to:content-type :content-transfer-encoding; b=h8foolS+944OoNvsV3BOMkMH86bX2ja23Z1Vr2DCnAWL2OScneZhuC8eadU80h3L7h xlslo1J/v0NEKQvcKA/nts8prvbSJ2mEA5h4UfsftUoHigF2o0nzH2wjj90xcESYFi7E mie6VP/h/oTVZDxbTjKjLoQ0SQKrvIHkPgSYY= I was reading through the 10.5.8 pthread mutex implementation (Libc-498.1.7/xnu-1228.15.4). I am stumped by a couple things, and I hope that someone here can shed some light on them. First: How might a thread enter this else-if clause in pthread_mutex_lock() (Libc/pthreads/pthread_mutex.c:333)? if (mutex->owner != (pthread_t)NULL) { if (mutex->waiters || mutex->owner != _PTHREAD_MUTEX_OWNER_SWITCHING) { … } else if (mutex->owner == _PTHREAD_MUTEX_OWNER_SWITCHING) { semaphore_t sem = mutex->sem; do { PTHREAD_MACH_CALL(semaphore_wait(sem), kern_res); } while (kern_res == KERN_ABORTED); mutex->sem = SEMAPHORE_NULL; restore_sem_to_pool(sem); } } In order to enter this clause, the mutex's owner would have to be _PTHREAD_MUTEX_OWNER_SWITCHING, but it would have to have no waiters. But the mutex's owner is only set to SWITCHING by pthread_mutex_unlock() when there are waiters. Further, the mutex structure's lock is used to protect changes to owner and waiters, so there would seem to be no way any thread could ever enter this clause. The clause's code assumes that mutex->sem's value is 1 (because it waits on it in order to restore its value to 0) and that the thread in the clause is the last waiter on the semaphore (because it returns the semaphore to the pool). But it seems to leave the mutex->order semaphore hanging. I assume this is a lack of imagination on my part: somehow, the mutex's state has become uncertain, mutex->sem has been signaled more times than expected (as far as I can tell, its value only ever veers between 0 and -1), and a waiter died somewhere unexpectedly. But try as I might, I can't imagine a set of threads and sequence of events that would result in this code being executed. Second: When might semaphore_wait_signal() return KERN_ABORTED? That is to say (per semaphore_convert_wait_result()), what might cause thread_block() to return THREAD_INTERRUPTED when assert_wait()ing with interruptible state THREAD_ABORTSAFE? This question is prompted by this bit from pthread_mutex_lock() (starting at line 316): PTHREAD_MACH_CALL(semaphore_wait_signal(sem, order), kern_res); while (kern_res == KERN_ABORTED) { PTHREAD_MACH_CALL(semaphore_wait(sem), kern_res); } This appears to be intended to ensure sem gets waited on no matter what. Blocking on mutex->sem is essential to the mutex implementation: mutex->order appears to ensure threads reach this section one-by-one and queue up on mutex->sem in FIFO order. In order to block waiting for the mutex to be unlocked, the thread has to wait on mutex->sem. Perhaps this is just standard Mach kernel defensive coding? Or, more likely, is there some essential contextual information I am unaware of? Thank you for your help, —Jeremy _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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[IPFW] Why "ipfw set disable" can't disable set number larger than or equal to 24?
by Jan Deng 09 Oct '10

09 Oct '10

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Re: alternatives to signals like try/catch
by Quinn "The Eskimo!" 07 Oct '10

07 Oct '10

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com On 7 Oct 2010, at 05:49, Terry Lambert wrote: > I'll agree with Mike that you're not going to be able to do this selectively based on the code you are currently running in, and that you'll interfere with other things that try to grab the exception port -- for example, all debuggers. Programs like GDB and CrashReporter tend to sit on the task exception port (or the host exception port). If you're catching exceptions within a process, it's fairly safe to do so on the thread exception port. This is quite commonly used by alternatively runtime environments, notably Apple's own Java VM. S+E -- Quinn "The Eskimo!" <http://www.apple.com/developer/> Apple Developer Relations, Developer Technical Support, Core OS/Hardware _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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Re: alternatives to signals like try/catch
by Terry Lambert 07 Oct '10

07 Oct '10

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com On Oct 6, 2010, at 8:45 PM, Daniel Walter wrote: > > However, you can certainly arrange to have exceptions delivered to your handler so that you can perform your own filtering. Your mistake is in assuming that you want to handle signals, which are not the primary delivery mechanism. > > What is the primary delivery mechanism? I have seen a reference to task_set_exception_ports somewhere, but have not found any real documentation of it. Read section 9.7 of Amit Singh's book "Mac OS X Internals. A Systems Approach". > Is this what you are talking about? Are signals layered on top of this? Exceptions set the AST_BSD on the thread for a hardware exception, or if it's a software exception, then whatever thread it happens to land on. This then causes ast_taken() to call bsd_ast() on the thread, a function located in bsd/kern/kern_sig.c, which is the code that implements signals by calling postsig(), which calls sendsig(), which invokes the signal trampoline in libc up in user space. Because the signal is delivered via an AST when the thread runs up to the user/kernel boundary, it's got a potentially large latency in delivery. It's also a persistent condition rather than an event. I'll agree with Mike that you're not going to be able to do this selectively based on the code you are currently running in, and that you'll interfere with other things that try to grab the exception port -- for example, all debuggers. -- Terry _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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