Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
Deepak is in India. I have also been able to replicate the problem using XOs manufactured in the same week (SN SHC037x). It's probably easiest if I send my SD cards to James. James, I'll contact you separately about this. Regards, Sridhar On 14 July 2012 03:32, Martin Langhoff mar...@laptop.org wrote: Hi folks, where is Deepak Muddhaa based? Any reason his failing XO and SD card can't be traded for good ones, and the failing units shipped to James, Miami or Boston, where we can look at things at a lower level? We'll gladly provide a replacement unit. I appreciate all the analysis, but it' is apparent that it is being done on rather poor data. Hands-on debugging wins. cheers, m On Sun, Jun 24, 2012 at 11:32 PM, James Cameron qu...@laptop.org wrote: Thanks for your reply! On Mon, Jun 25, 2012 at 11:16:26AM +1000, Sridhar Dhanapalan wrote: On 21 June 2012 16:14, James Cameron qu...@laptop.org wrote: On Thu, Jun 21, 2012 at 02:37:35PM +1000, Sridhar Dhanapalan wrote: On 16 June 2012 17:08, James Cameron qu...@laptop.org wrote: That means the hang should not exceed 15 seconds. ?Is this what you find? ?If not, then this casts doubt on your solution. I'm going to propose something extremely hackish: [...] Just to remind you that I'm still interested to know if the hang you observe exceeds 15 seconds or not. ?I've not had the time to reproduce this hang yet. ?Building a mental model of the problem is important to me, because I can sometimes resolve a problem if I have a good model. Yes; we have left it for several minutes and no shutdown has occurred. Ooh, I'm surprised. This observation, and the statistical results from your temporary solution (a delay), implies a combination effect, of both the processes not yet terminated, and the umount, leading to a process hang of umount. I can't think of a hack that would meet the requirements: - survive the process deletion steps, and - detect the stalled umount process. I guess you might try remounting the filesystem -o sync, just to further shift the timing. The problem needs a kernel developer to reproduce it. Do you have a way to encourage the problem to occur? If it can be made to occur on a higher percentage of shutdowns, it becomes easier to debug. For instance, there is a two second delay in the code, so does the hang occur more frequently if this is reduced to zero? The XO-1.75 CPU has a hardware watchdog that could be used for this, but you aren't likely to ever have a heat problem with XO-1.75. That is interesting. Why is that? I take it you mean why won't you have a heat problem with XO-1.75. There are two new characteristics of the XO-1.75 over the XO-1.5: 1. the maximum power draw of the XO-1.75 at full utilisation is a long way below that of the XO-1.5. In a scenario where the laptop is powered on and insulated from cooling air flow, this means: 1.a. the temperature rise toward equilibrium will be slower, 1.b. the equilibrium temperature will be lower for a given level of insulation, (stacking, or cloth covers, or both), 1.c. the insulation will have to be far greater to achieve the same equilibrium temperature. 2. the XO-1.75 has a thermal protection feature that forces the power off if the temperature of the CPU exceeds 85 degrees C, rather than slowing or stopping the CPU as on XO-1.5. In a scenario where the laptop is powered on and insulated from cooling air flow, this means: 2.a. the temperature rise will be interrupted by a sudden loss of input heat, rather than be slowed by a gradual loss of input heat, 2.b. the insulation will have to be far far greater to achieve the same equilibrium temperature. In this scenario, the heat spreader has very little bearing on the matter. The heat spreader relies on cooling air flow to the top of the case. If there is no air flow, the heat spreader is ineffective. The new thermal protection feature isn't a perfect protection; the battery charge circuit remains powered. So a laptop held between very good insulation (e.g. thick polystyrene with sealed edges) with a flat battery will still heat up, but not nearly as much as one with an active CPU. (Please, test this yourselves with an IR thermometer. If you don't have one, the closest in Sydney to you would be at the Jaycar store at 127 York St.) -- James Cameron http://quozl.linux.org.au/ -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
Hi folks, where is Deepak Muddhaa based? Any reason his failing XO and SD card can't be traded for good ones, and the failing units shipped to James, Miami or Boston, where we can look at things at a lower level? We'll gladly provide a replacement unit. I appreciate all the analysis, but it' is apparent that it is being done on rather poor data. Hands-on debugging wins. cheers, m On Sun, Jun 24, 2012 at 11:32 PM, James Cameron qu...@laptop.org wrote: Thanks for your reply! On Mon, Jun 25, 2012 at 11:16:26AM +1000, Sridhar Dhanapalan wrote: On 21 June 2012 16:14, James Cameron qu...@laptop.org wrote: On Thu, Jun 21, 2012 at 02:37:35PM +1000, Sridhar Dhanapalan wrote: On 16 June 2012 17:08, James Cameron qu...@laptop.org wrote: That means the hang should not exceed 15 seconds. ?Is this what you find? ?If not, then this casts doubt on your solution. I'm going to propose something extremely hackish: [...] Just to remind you that I'm still interested to know if the hang you observe exceeds 15 seconds or not. ?I've not had the time to reproduce this hang yet. ?Building a mental model of the problem is important to me, because I can sometimes resolve a problem if I have a good model. Yes; we have left it for several minutes and no shutdown has occurred. Ooh, I'm surprised. This observation, and the statistical results from your temporary solution (a delay), implies a combination effect, of both the processes not yet terminated, and the umount, leading to a process hang of umount. I can't think of a hack that would meet the requirements: - survive the process deletion steps, and - detect the stalled umount process. I guess you might try remounting the filesystem -o sync, just to further shift the timing. The problem needs a kernel developer to reproduce it. Do you have a way to encourage the problem to occur? If it can be made to occur on a higher percentage of shutdowns, it becomes easier to debug. For instance, there is a two second delay in the code, so does the hang occur more frequently if this is reduced to zero? The XO-1.75 CPU has a hardware watchdog that could be used for this, but you aren't likely to ever have a heat problem with XO-1.75. That is interesting. Why is that? I take it you mean why won't you have a heat problem with XO-1.75. There are two new characteristics of the XO-1.75 over the XO-1.5: 1. the maximum power draw of the XO-1.75 at full utilisation is a long way below that of the XO-1.5. In a scenario where the laptop is powered on and insulated from cooling air flow, this means: 1.a. the temperature rise toward equilibrium will be slower, 1.b. the equilibrium temperature will be lower for a given level of insulation, (stacking, or cloth covers, or both), 1.c. the insulation will have to be far greater to achieve the same equilibrium temperature. 2. the XO-1.75 has a thermal protection feature that forces the power off if the temperature of the CPU exceeds 85 degrees C, rather than slowing or stopping the CPU as on XO-1.5. In a scenario where the laptop is powered on and insulated from cooling air flow, this means: 2.a. the temperature rise will be interrupted by a sudden loss of input heat, rather than be slowed by a gradual loss of input heat, 2.b. the insulation will have to be far far greater to achieve the same equilibrium temperature. In this scenario, the heat spreader has very little bearing on the matter. The heat spreader relies on cooling air flow to the top of the case. If there is no air flow, the heat spreader is ineffective. The new thermal protection feature isn't a perfect protection; the battery charge circuit remains powered. So a laptop held between very good insulation (e.g. thick polystyrene with sealed edges) with a flat battery will still heat up, but not nearly as much as one with an active CPU. (Please, test this yourselves with an IR thermometer. If you don't have one, the closest in Sydney to you would be at the Jaycar store at 127 York St.) -- James Cameron http://quozl.linux.org.au/ -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On 21 June 2012 16:14, James Cameron qu...@laptop.org wrote: On Thu, Jun 21, 2012 at 02:37:35PM +1000, Sridhar Dhanapalan wrote: On 16 June 2012 17:08, James Cameron qu...@laptop.org wrote: That means the hang should not exceed 15 seconds. ?Is this what you find? ?If not, then this casts doubt on your solution. I'm going to propose something extremely hackish: [...] Just to remind you that I'm still interested to know if the hang you observe exceeds 15 seconds or not. I've not had the time to reproduce this hang yet. Building a mental model of the problem is important to me, because I can sometimes resolve a problem if I have a good model. Yes; we have left it for several minutes and no shutdown has occurred. If you disable the boot/shutdown animation, the shutdown sequence stops at this: http://dev.laptop.org.au/attachments/download/914/hang-on-shutdown.jpg That image is an attachment on the main issue: http://dev.laptop.org.au/issues/1033 The XO-1.75 CPU has a hardware watchdog that could be used for this, but you aren't likely to ever have a heat problem with XO-1.75. That is interesting. Why is that? Thanks, Sridhar ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
Thanks for your reply! On Mon, Jun 25, 2012 at 11:16:26AM +1000, Sridhar Dhanapalan wrote: On 21 June 2012 16:14, James Cameron qu...@laptop.org wrote: On Thu, Jun 21, 2012 at 02:37:35PM +1000, Sridhar Dhanapalan wrote: On 16 June 2012 17:08, James Cameron qu...@laptop.org wrote: That means the hang should not exceed 15 seconds. ?Is this what you find? ?If not, then this casts doubt on your solution. I'm going to propose something extremely hackish: [...] Just to remind you that I'm still interested to know if the hang you observe exceeds 15 seconds or not. ?I've not had the time to reproduce this hang yet. ?Building a mental model of the problem is important to me, because I can sometimes resolve a problem if I have a good model. Yes; we have left it for several minutes and no shutdown has occurred. Ooh, I'm surprised. This observation, and the statistical results from your temporary solution (a delay), implies a combination effect, of both the processes not yet terminated, and the umount, leading to a process hang of umount. I can't think of a hack that would meet the requirements: - survive the process deletion steps, and - detect the stalled umount process. I guess you might try remounting the filesystem -o sync, just to further shift the timing. The problem needs a kernel developer to reproduce it. Do you have a way to encourage the problem to occur? If it can be made to occur on a higher percentage of shutdowns, it becomes easier to debug. For instance, there is a two second delay in the code, so does the hang occur more frequently if this is reduced to zero? The XO-1.75 CPU has a hardware watchdog that could be used for this, but you aren't likely to ever have a heat problem with XO-1.75. That is interesting. Why is that? I take it you mean why won't you have a heat problem with XO-1.75. There are two new characteristics of the XO-1.75 over the XO-1.5: 1. the maximum power draw of the XO-1.75 at full utilisation is a long way below that of the XO-1.5. In a scenario where the laptop is powered on and insulated from cooling air flow, this means: 1.a. the temperature rise toward equilibrium will be slower, 1.b. the equilibrium temperature will be lower for a given level of insulation, (stacking, or cloth covers, or both), 1.c. the insulation will have to be far greater to achieve the same equilibrium temperature. 2. the XO-1.75 has a thermal protection feature that forces the power off if the temperature of the CPU exceeds 85 degrees C, rather than slowing or stopping the CPU as on XO-1.5. In a scenario where the laptop is powered on and insulated from cooling air flow, this means: 2.a. the temperature rise will be interrupted by a sudden loss of input heat, rather than be slowed by a gradual loss of input heat, 2.b. the insulation will have to be far far greater to achieve the same equilibrium temperature. In this scenario, the heat spreader has very little bearing on the matter. The heat spreader relies on cooling air flow to the top of the case. If there is no air flow, the heat spreader is ineffective. The new thermal protection feature isn't a perfect protection; the battery charge circuit remains powered. So a laptop held between very good insulation (e.g. thick polystyrene with sealed edges) with a flat battery will still heat up, but not nearly as much as one with an active CPU. (Please, test this yourselves with an IR thermometer. If you don't have one, the closest in Sydney to you would be at the Jaycar store at 127 York St.) -- James Cameron http://quozl.linux.org.au/ ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On Thu, Jun 21, 2012 at 02:37:35PM +1000, Sridhar Dhanapalan wrote: On 16 June 2012 17:08, James Cameron qu...@laptop.org wrote: That means the hang should not exceed 15 seconds. ?Is this what you find? ?If not, then this casts doubt on your solution. I'm going to propose something extremely hackish: [...] Just to remind you that I'm still interested to know if the hang you observe exceeds 15 seconds or not. I've not had the time to reproduce this hang yet. Building a mental model of the problem is important to me, because I can sometimes resolve a problem if I have a good model. The reason that 15 seconds threshold is important, is that the /etc/init.d/functions is designed to finish the unmounting by then. If it is not finishing, then this hang is at root a kernel problem. [...] can we have the XO perform a hard power-off if the software shutdown sequence does not complete within 30 seconds? Yes. However, the time would likely be better spent by a developer in understanding what is happening. Without that, there's a strong risk that the hack may be ineffective, because whatever is stopping the shutdown might also stop the hack. It isn't about elegance, it's about effectiveness. Hack type 1: in /etc/init.d/halt fork a process that sleeps for 30 seconds and then forces a power down: (sleep 30 ; /sbin/halt -f -d -p) Hack type 2: in /etc/init.d/halt fork a process that sleeps for 30 seconds and then sends a power down command to the embedded controller: (sleep 30 ; echo 55:0 /sys/power/ec) But both these approaches don't work for me. I presume it is because the forked process is killed by /etc/init.d/halt One might add code to /etc/init.d/halt to check for elapsed time and force a power off, but this would be blocked if a command hangs. The XO-1.5 embedded controller firmware might also be modified, to provide a watchdog, but my guess is that will take a lot of engineering effort. Again, that effort, if it is to be spent, would be better spent in diagnosis and debugging. Ideally this would be managed by some kind of hardware watchdog, but maybe there's a cheap-and-nasty version we can implement in software. The XO-1.75 CPU has a hardware watchdog that could be used for this, but you aren't likely to ever have a heat problem with XO-1.75. I don't know if the XO-1.5 CPU has a hardware watchdog. -- James Cameron http://quozl.linux.org.au/ ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On 16 June 2012 17:08, James Cameron qu...@laptop.org wrote: That means the hang should not exceed 15 seconds. Is this what you find? If not, then this casts doubt on your solution. I'm going to propose something extremely hackish: can we have the XO perform a hard power-off if the software shutdown sequence does not complete within 30 seconds? Ideally this would be managed by some kind of hardware watchdog, but maybe there's a cheap-and-nasty version we can implement in software. The problem we want to eliminate is that XOs are being told to shutdown and are then closed and placed in an XOP charging rack. If an XO does not actually turn off and remains on while in the rack and charging, it has the potential to overheat. We have seen cases where XOs get so hot that the plastic on the touchpad and even on the outer casing becomes warped. If a problem like that becomes widespread, it can be *major* for us. I understand that it's not the most elegant solution, but from a deployment perspective we need a failsafe to protect the hardware. Sridhar Sridhar Dhanapalan Engineering Manager One Laptop per Child Australia ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
G'day Anish, I don't think you should conflate the shutdown issue with slower than claimed microSD cards. The shutdown issue may be a symptom, combining Fedora's assumptions about how quickly the kernel will finish writing data, with the microSD cards being much slower than the hard disks the halt script was written for. Your fix of adding delay was based on the assumption that more time was needed for processes to be killed. I disagree. I think the delay was reducing the probability of dirty blocks in the cache, and you would have observed an improvement because of that alone. Your fix of adding a sync before umount might work. I'm interested to know how successful that is. Another thing you could do is reduce the retry timers and counters in __umount_loop so that it abandons the wait sooner, resulting in the laptop powering down with the filesystem still mounted. A better scenario than staying powered. __umount_loop tries an umount. In your photograph [12] that first umount failed with umount: /home: device is busy. __umount_loop then counts the number of filesystems yet to be unmounted, allowing two seconds to elapse before it sends another signal to each process that has references to the filesystem. It then sleeps for three seconds before retrying up to 3 times. __umount_loop is then abandoned. That means the hang should not exceed 15 seconds. Is this what you find? If not, then this casts doubt on your solution. The umount2: Device or resource busy is interesting. I don't see this if I try to umount a device that is busy on Fedora 14. It may suggest that the umount is failing for a reason other than filesystems with remaining references or dirty blocks. I really doubt that fixing the microSD card write performance will properly fix this hang problem. Fixing the microSD card write performance, if it is below a specification, should be done anyway. It may well reduce the frequency of the hang. But as far as I can see, it isn't the only contributor to the hang. You seem to have settled on a myth. You seem to believe, based on selected evidence, that the problem is entirely to do with microSD cards. You continue to seek such evidence, but I think you should seek other evidence. -- James Cameron http://quozl.linux.org.au/ ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
I doubt that this issue is your problem. But in response to one remark: On the theory that these writes may be stalling due to the block number, (and we haven't seen any evidence yet of this), you can test for that by repeating the writes... There *is* evidence that accesses to some block numbers in MLC flash chips are much faster or slower than others (like 5x slower). They seem to be designed with fast blocks and slow blocks, though this is undocumented. There is no interface for telling the software which is which (except by actual measurement of the responsiveness of the chip -- and in microSD cards, accesses are mediated by a Flash Translation Layer of unknown characteristics). See: Characterizing Flash Memory: Anomalies, Observations, and Applications Laura Grupp, Adrian Caulfield, Joel Coburn, Steven Swanson, Eitan Yaakobi and Paul Siegel UCSD Tech Report CS2009-0946 August 19, 2009 Unfortunately the amazing people at UCSD fail to put up their archival tech reports in readily accessible PDFs. (It seems to be some sort of half-assed DRM system, since they yammer about copyrights on the same page.) They do have a mangled (OCR'd!) abstract here: http://csetechrep.ucsd.edu/Dienst/UI/2.0/Describe/ncstrl.ucsd_cse/CS2009-0946 and a mangled 18MB PostScript version available here: http://csetechrep.ucsd.edu/Dienst/Repository/2.0/Body/ncstrl.ucsd_cse/CS2009-0946/postscript The Wayback Machine failed to capture it while it was there. But I got the PDF from them when they had published it in 2009. I have put up the 1.5MB PDF temporarily here for research purposes: http://www.toad.com/TEMP-Grupp-2009-TR-FTest.pdf with the slides here: http://www.toad.com/TEMP-Grupp-2009-FMS-FTest.pdf John ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
Hi Martin, James et. al. It seems that the microSD card was definitely one of the main reasons why the hang on shutdown was happening [1] [1] http://dev.laptop.org.au/issues/1323 Cheers, Anish On Fri, Jun 15, 2012 at 7:45 AM, Anish Mangal an...@activitycentral.com wrote: On Fri, Jun 15, 2012 at 4:09 AM, James Cameron qu...@laptop.org wrote: On Thu, Jun 14, 2012 at 06:51:58PM +0530, Anish Mangal wrote: * Insert bad microSD. Flash the new build (using fs-update) * Test * Insert good microSD. Flash the new build (using fs-update) * Test In your testing, please also control for the version of Open Firmware used at the fs-update step. Good point. Deepak, please take note of it in your testing. The firmware version while testing with the old and new microSD cards should be same. -- James Cameron http://quozl.linux.org.au/ ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
I do not wish to constrain your investigation at all, please continue investigating, but I do have some comments and speculations. Yes, the microSD card cannot be excluded as a cause. But unless there are other symptoms associated with the microSD card, effort should be concentrated on finding the root cause of the hang, using Linux debugging techniques. The transactions that are given to the microSD card during shutdown should be normal block read and writes, as the filesystem is prepared for unmounting. There's nothing unusual about these transactions, except that some of them may be located in a particular block range. So it is unlikely that this will be a cause of the hang. But you may want to exclude it. On the theory that these writes may be stalling due to the block number, (and we haven't seen any evidence yet of this), you can test for that by repeating the writes in a controlled fashion, such as by booting from an external SD card or USB drive, and using Linux to mount and umount the internal microSD card partitions. If you find this unreliable, then it is a critical finding. If you find this reliable, then you can exclude the theory of writes stalling due to block number. There is a possibility that the contributed behaviour is tied to a model of microSD card, rather than a specific microSD card. We use multiple qualified sources in manufacturing. You might identify the manufacturer's identity and configuration of the microSD card. You can do this in Open Firmware using: ok select int ok show-cid There are, no doubt, ways to do this in Linux as well, but I do not recall the details. I look forward to hearing what your Linux debugging techniques uncover. Ask yourself this question; what is preventing the power off command from being delivered to the embedded controller by the kernel? Is it because it was not sent? If so, why? Is it because it was sent (per serial port evidence) but not obeyed? If so, why is it that the power button responds? Is there any serial port evidence of the power button being detected by the kernel at the point of the hang? And so on. -- James Cameron http://quozl.linux.org.au/ ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi James, Please have a look at https://dev.laptop.org.au/issues/1033#note-64 which was the email sent some time ago internally when the workaround for this was just found. * It is currently difficult for us to follow linux debugging techniques as the broken laptop and good/bad microSD cards are with someone with only basic linux knowledge. (and this was a restriction during initial debug too) * We think the problem was with the SD cards (perhaps a specific batch of them), and I think our findings establish that with some confidence. * The reason why the laptop was not being shutdown was due to a race condition. The halt script was expecting the processed to get killed within a certain amount of time, which they weren't. Just delaying that expected time point (by which the processes should be killed) worked for us. * As for further debugging, I could have the SD card shipped to me, or anybody looking to spend time on it, but we must be confident enough that the problem lies there (which I think it does). On Saturday 16 June 2012 05:46 AM, James Cameron wrote: I do not wish to constrain your investigation at all, please continue investigating, but I do have some comments and speculations. Yes, the microSD card cannot be excluded as a cause. But unless there are other symptoms associated with the microSD card, effort should be concentrated on finding the root cause of the hang, using Linux debugging techniques. The transactions that are given to the microSD card during shutdown should be normal block read and writes, as the filesystem is prepared for unmounting. There's nothing unusual about these transactions, except that some of them may be located in a particular block range. So it is unlikely that this will be a cause of the hang. But you may want to exclude it. On the theory that these writes may be stalling due to the block number, (and we haven't seen any evidence yet of this), you can test for that by repeating the writes in a controlled fashion, such as by booting from an external SD card or USB drive, and using Linux to mount and umount the internal microSD card partitions. If you find this unreliable, then it is a critical finding. If you find this reliable, then you can exclude the theory of writes stalling due to block number. There is a possibility that the contributed behaviour is tied to a model of microSD card, rather than a specific microSD card. We use multiple qualified sources in manufacturing. You might identify the manufacturer's identity and configuration of the microSD card. You can do this in Open Firmware using: ok select int ok show-cid There are, no doubt, ways to do this in Linux as well, but I do not recall the details. I look forward to hearing what your Linux debugging techniques uncover. Ask yourself this question; what is preventing the power off command from being delivered to the embedded controller by the kernel? Is it because it was not sent? If so, why? Is it because it was sent (per serial port evidence) but not obeyed? If so, why is it that the power button responds? Is there any serial port evidence of the power button being detected by the kernel at the point of the hang? And so on. - -- Anish Mangal Dextrose Project Manager Activity Central -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQEcBAEBAgAGBQJP2/xTAAoJEBoxUdDHDZVp33QH/jfYUQYyQLLt6+cAH/aYAEhU yymgGEZzmCqhn+i92CuD1LoChblV+mYNVCQH0DqLe8aoDyzyqoOsdZ7lLgv+FQdv niIBQxS5q7J+sKOB4pzVgXes/2HAn3fj/VyRHUkqgLsvYyzfA2ZMm7+qYGyGZ410 QIU6oRkJqwIrGq+hAd8dyGogFtByB3xOquCWeBnIF63MZ0mr7/Agjdek8a+h+Y+q 5nGfd+HuRTnzfgQezx+kX3K7a7ozj3lOpMDD5pAbXIbLKNWeyoAoUh31suGmTJO0 bWwbzDDze+g1VqaJOF/AuAiMuQi1k9ZbUlbhhlqRwBNAPWggEtH+3Iqj3flm+VE= =ktQp -END PGP SIGNATURE- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
FYI, The testing efforts (with old v new SD cards are being recorded at http://dev.laptop.org.au/issues/1323) On Wed, Jun 13, 2012 at 12:57 AM, Jerry Vonau jvo...@shaw.ca wrote: On Mon, 2012-06-11 at 20:06 +0530, Anish Mangal wrote: On Tue, Jun 5, 2012 at 8:11 PM, Martin Langhoff mar...@laptop.org wrote: On Tue, Jun 5, 2012 at 10:37 AM, Martin Langhoff mar...@laptop.org wrote: - Seems to be related to umount of /home failing. Adding sync ; sleep 2; before umount seems to cure it; that's their current workaround. Cutting the CC list down to only devel@ for debugging -- Anish, thanks for reporting this. Couple of questions/requests: - can you give us the exact patch showing the workaround you are applying? Jerry, can you pls provide the same? Sorry not patching on the fly with this one, just copying a revised file in place via OOB. You could do diff against a stock file and what we're using from: https://dev.laptop.org.au/projects/xo-au/repository/revisions/dex3/raw/olpc-os-builder/sub-files/halt Jerry - very interested in the microSD swap between good and bad units. Let us know how it goes. We just shipped a good SD card to the person with the 'failing' laptop. Expect to hear back very soon. On 12.1.0 the switch to systemd completely reworks the shutdown / umount process; so if it affects Fedora or OLPC releases, the scope is 11.3.x / F14. Very unlikely that we see it, at least in this particular incarnation, on 12.1.0. cheers, m -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On Thu, Jun 14, 2012 at 12:03:39PM +0530, Anish Mangal wrote: FYI, The testing efforts (with old v new SD cards are being recorded at http://dev.laptop.org.au/issues/1323) I've found microSD card performance can change slightly as a result of a reflash. On #1323 it seems an fs-update was done prior to the test. If you wish to keep analysing it to look at the differences between microSD cards, then: - make the same number of shutdown tests for both the original microSD card and the different microSD card, so that the difference can be established statistically. - restrict the testing to microSD cards from OLPC that we have qualified. - widen the testing to microSD cards from OLPC that have had little use. - look for difference in behaviour with the microSD card written to in one laptop and used in another ... 'cause I'd hate to find that this was due to fs-update. I predict that this is a race condition during shutdown, which may yield better to analysis with serial port attached. The 11.3.x builds maintain a getty and shell on the serial port, if I recall correctly, and this may still be responsive at the time of the hang. Using that shell it may be possible to find what processes are happening. If that shell isn't available, try adding it. As to what is causing the different timing between different laptops, I predict that this is dependent on microSD card performance variation. These cards contain a FLASH translation layer that processes SD commands and manages the remapping from virtual blocks to physical cells. Their performance can vary. I did consider the possibility of power cycling timing during fs-update, but in the XO-1.5 units you have the microSD power is managed by the embedded controller. The SD card is power cycled by Open Firmware, but not the microSD card. Another thing you might try is run a microSD card in an SD card adapter, see if there is a difference. #1323 needs a pointer to your earlier work on #1033. I found it in mail, but I shouldn't have had to. ;-} -- James Cameron http://quozl.linux.org.au/ ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On Thursday 14 June 2012 01:16 PM, James Cameron wrote: On Thu, Jun 14, 2012 at 12:03:39PM +0530, Anish Mangal wrote: FYI, The testing efforts (with old v new SD cards are being recorded at http://dev.laptop.org.au/issues/1323) I've found microSD card performance can change slightly as a result of a reflash. On #1323 it seems an fs-update was done prior to the test. If you wish to keep analysing it to look at the differences between microSD cards, then: - make the same number of shutdown tests for both the original microSD card and the different microSD card, so that the difference can be established statistically. - restrict the testing to microSD cards from OLPC that we have qualified. See http://dev.laptop.org.au/issues/1323#note-3 for the above two points. We're testing with microSD cards that came with the OLPC laptops (i.e. OLPC approved/validated) - widen the testing to microSD cards from OLPC that have had little use. - look for difference in behaviour with the microSD card written to in one laptop and used in another ... 'cause I'd hate to find that this was due to fs-update. Perhaps this could be one next step. Right now, we're doing (we have one xo-1.5 and two microSD cards, one probably 'good', and the other one 'bad', both OLPC approved) * Insert bad microSD. Flash the new build (using fs-update) * Test * Insert good microSD. Flash the new build (using fs-update) * Test I predict that this is a race condition during shutdown, which may yield better to analysis with serial port attached. The 11.3.x builds maintain a getty and shell on the serial port, if I recall correctly, and this may still be responsive at the time of the hang. Using that shell it may be possible to find what processes are happening. If that shell isn't available, try adding it. That's what we seem to have established in our initial debug (I think it should be present somewhere in the thread history or the ticket). Let me know if you can't find it. As to what is causing the different timing between different laptops, I predict that this is dependent on microSD card performance variation. These cards contain a FLASH translation layer that processes SD commands and manages the remapping from virtual blocks to physical cells. Their performance can vary. I did consider the possibility of power cycling timing during fs-update, but in the XO-1.5 units you have the microSD power is managed by the embedded controller. The SD card is power cycled by Open Firmware, but not the microSD card. The first thing we're trying to establish is that the problem happens primarily due to a microSD card. Once we verify that it is the correct direction, we'll go deeper into debug. Another thing you might try is run a microSD card in an SD card adapter, see if there is a difference. #1323 needs a pointer to your earlier work on #1033. I found it in mail, but I shouldn't have had to. ;-} Its already present in the 'Related Tickets' section on the same page. - -- Anish -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQEcBAEBAgAGBQJP2eV2AAoJEBoxUdDHDZVpx08H/jY46mT9vRI5Zn530BoeU4GJ 0LD2Ycf/0XWLjVPx7oS6cuySiOV2qWnNFUbh0iRVXOSHjafnm2Xsx2tMZX9t3CRe JR3Yuzz1ymBPaYTK405+Kf5BadIHp6i0cJAG1jMtEvO7VvgQ8AxQCfiHOyjgxYe8 skI7w9xjSpIjB0nT76ePNaGG5FtLKQXMIixhcEbJt8pRoiBOLKYo2N6mEXgfniEU k/UyvIbuMShdQzFJAIcQm8uEw8kZCHp4bQzjh+XMOL/H3eaL6JQT8K1bep9Ps+V6 YnC1D4ggFIm2uFUXy/aag0yaFepDoBvT3g0e66awPT/ZcT3p3+TwF8AlilwVOkw= =GF4u -END PGP SIGNATURE- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On Fri, Jun 15, 2012 at 4:09 AM, James Cameron qu...@laptop.org wrote: On Thu, Jun 14, 2012 at 06:51:58PM +0530, Anish Mangal wrote: * Insert bad microSD. Flash the new build (using fs-update) * Test * Insert good microSD. Flash the new build (using fs-update) * Test In your testing, please also control for the version of Open Firmware used at the fs-update step. Good point. Deepak, please take note of it in your testing. The firmware version while testing with the old and new microSD cards should be same. -- James Cameron http://quozl.linux.org.au/ ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On Mon, 2012-06-11 at 20:06 +0530, Anish Mangal wrote: On Tue, Jun 5, 2012 at 8:11 PM, Martin Langhoff mar...@laptop.org wrote: On Tue, Jun 5, 2012 at 10:37 AM, Martin Langhoff mar...@laptop.org wrote: - Seems to be related to umount of /home failing. Adding sync ; sleep 2; before umount seems to cure it; that's their current workaround. Cutting the CC list down to only devel@ for debugging -- Anish, thanks for reporting this. Couple of questions/requests: - can you give us the exact patch showing the workaround you are applying? Jerry, can you pls provide the same? Sorry not patching on the fly with this one, just copying a revised file in place via OOB. You could do diff against a stock file and what we're using from: https://dev.laptop.org.au/projects/xo-au/repository/revisions/dex3/raw/olpc-os-builder/sub-files/halt Jerry - very interested in the microSD swap between good and bad units. Let us know how it goes. We just shipped a good SD card to the person with the 'failing' laptop. Expect to hear back very soon. On 12.1.0 the switch to systemd completely reworks the shutdown / umount process; so if it affects Fedora or OLPC releases, the scope is 11.3.x / F14. Very unlikely that we see it, at least in this particular incarnation, on 12.1.0. cheers, m -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On Tue, Jun 5, 2012 at 8:11 PM, Martin Langhoff mar...@laptop.org wrote: On Tue, Jun 5, 2012 at 10:37 AM, Martin Langhoff mar...@laptop.org wrote: - Seems to be related to umount of /home failing. Adding sync ; sleep 2; before umount seems to cure it; that's their current workaround. Cutting the CC list down to only devel@ for debugging -- Anish, thanks for reporting this. Couple of questions/requests: - can you give us the exact patch showing the workaround you are applying? Jerry, can you pls provide the same? - very interested in the microSD swap between good and bad units. Let us know how it goes. We just shipped a good SD card to the person with the 'failing' laptop. Expect to hear back very soon. On 12.1.0 the switch to systemd completely reworks the shutdown / umount process; so if it affects Fedora or OLPC releases, the scope is 11.3.x / F14. Very unlikely that we see it, at least in this particular incarnation, on 12.1.0. cheers, m -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On Fri, Jun 8, 2012 at 6:26 PM, Anish Mangal an...@activitycentral.orgwrote: On Fri, Jun 8, 2012 at 5:45 PM, Kevin Gordon kgordon...@gmail.com wrote: Sitting in a lab here in Kenya with about 60 XO 1.5's all at standard 885 Did shutdowns on all boxes 3 times (180 shutdowns) - all with right-click on centre icon and choose shutdown - after they were up for 5 mins or more. Results: 160 normal shutdowns 20 hang on warnings page No machines hung 3 times 4 machines hung twice 12 machines hung once. tap on power button shut hung machines off. Was it a tap, or an extended press (longer duration, until the machine powered off) It is the extended press and hold, not like the tap twice to power off timing, sorry for the poor choice of words :-) In any case, can you note down the Serial Nos. of the machines that hung? They are all out in the schools now, but I can state that the serial numbers are all in the range: SHC13100D00 to SHC13100DFF, as all of the machines in this batch are from a single order of 100 machines. Thanks! Cheers KG On Tue, Jun 5, 2012 at 11:55 PM, Martin Langhoff mar...@laptop.org wrote: On Tue, Jun 5, 2012 at 4:43 PM, Tom Parker t...@carrott.org wrote: We'll do some explicit testing of shutdown on Saturday. Fantastic, thanks! m -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On Sat, Jun 9, 2012 at 3:43 AM, Anish Mangal an...@sugarlabs.org wrote: On Sat, Jun 9, 2012 at 2:22 AM, Walter Bender walter.ben...@gmail.com wrote: On Tue, Jun 5, 2012 at 10:37 AM, Martin Langhoff mar...@laptop.org wrote: Hi folks, the Dextrose team has been hunting a bug on XO-1.5, on their variant of 11.3.x (Dextrose 3 or DX3), and they are pointing out that it could be a latent or unreported problem in 11.3.x series. It could also be a problem in their modifications. While they continue to investigate, it is important to hear whether anyone has seen XO-1.5s handing during shutdown, on the Warnings screen. - It seems to affect some units, not all. So far it has been seen on 3 units with SN starting with SHC037 . - Units affected show the symptoms 2 out of 5 boots. - Seems to be related to umount of /home failing. Adding sync ; sleep 2; before umount seems to cure it; that's their current workaround. - Their debugging adventures are documented at http://dev.laptop.org.au/issues/1033 - They will be checking whether the symptoms follow the microSD card or the motherboard, swapping microSD with a good unit. Why is this important? When the unit hangs during shutdown, it is left in a condition where it can overheat, potentially damaging the unit. The bottom line: have you seen this issue on XO-1.5 + 11.3.x? Even if ocassionally? Let us know, and join the bug-hunting party. cheers, m -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel While I haven't seen the exact symptoms described here, I have seen some problems here in Chachapoyas. XO 1.5s running 11.3.1. It seems that machines that are running for quite some time with very active use eventually hang. I grabbed some longs from a Browse session, which seems to be the activity running when the crashes happen, but looking at the logs, it seems to be something failing at a lower level. See http://bugs.sugarlabs.org/ticket/3678 Also, at times, Restart fails to restart. In our specific case (of this problem on an XO-1.5 running dx3), the hang was occurring even when almost no activity was done, i.e. start the XO, wait for sugar boot, shutdown the XO. Does dx3 have a different partition for /home as part of the standard dx3 build? If so I vaguely remember a hang issue on shutdown on generic F-14 with separate /home but F-14 was a while ago so I'm not sure but it might be worthwhile doing a google / bugzilla search of mainline Fedora bugs/lists/wiki to see if it was a general problem that was fixed upstream. Peter ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
Sitting in a lab here in Kenya with about 60 XO 1.5's all at standard 885 Did shutdowns on all boxes 3 times (180 shutdowns) - all with right-click on centre icon and choose shutdown - after they were up for 5 mins or more. Results: 160 normal shutdowns 20 hang on warnings page No machines hung 3 times 4 machines hung twice 12 machines hung once. tap on power button shut hung machines off. Cheers KG On Tue, Jun 5, 2012 at 11:55 PM, Martin Langhoff mar...@laptop.org wrote: On Tue, Jun 5, 2012 at 4:43 PM, Tom Parker t...@carrott.org wrote: We'll do some explicit testing of shutdown on Saturday. Fantastic, thanks! m -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On Fri, Jun 8, 2012 at 5:45 PM, Kevin Gordon kgordon...@gmail.com wrote: Sitting in a lab here in Kenya with about 60 XO 1.5's all at standard 885 Did shutdowns on all boxes 3 times (180 shutdowns) - all with right-click on centre icon and choose shutdown - after they were up for 5 mins or more. Results: 160 normal shutdowns 20 hang on warnings page No machines hung 3 times 4 machines hung twice 12 machines hung once. tap on power button shut hung machines off. Was it a tap, or an extended press (longer duration, until the machine powered off) In any case, can you note down the Serial Nos. of the machines that hung? Thanks! Cheers KG On Tue, Jun 5, 2012 at 11:55 PM, Martin Langhoff mar...@laptop.org wrote: On Tue, Jun 5, 2012 at 4:43 PM, Tom Parker t...@carrott.org wrote: We'll do some explicit testing of shutdown on Saturday. Fantastic, thanks! m -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On Tue, Jun 5, 2012 at 10:37 AM, Martin Langhoff mar...@laptop.org wrote: Hi folks, the Dextrose team has been hunting a bug on XO-1.5, on their variant of 11.3.x (Dextrose 3 or DX3), and they are pointing out that it could be a latent or unreported problem in 11.3.x series. It could also be a problem in their modifications. While they continue to investigate, it is important to hear whether anyone has seen XO-1.5s handing during shutdown, on the Warnings screen. - It seems to affect some units, not all. So far it has been seen on 3 units with SN starting with SHC037 . - Units affected show the symptoms 2 out of 5 boots. - Seems to be related to umount of /home failing. Adding sync ; sleep 2; before umount seems to cure it; that's their current workaround. - Their debugging adventures are documented at http://dev.laptop.org.au/issues/1033 - They will be checking whether the symptoms follow the microSD card or the motherboard, swapping microSD with a good unit. Why is this important? When the unit hangs during shutdown, it is left in a condition where it can overheat, potentially damaging the unit. The bottom line: have you seen this issue on XO-1.5 + 11.3.x? Even if ocassionally? Let us know, and join the bug-hunting party. cheers, m -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel While I haven't seen the exact symptoms described here, I have seen some problems here in Chachapoyas. XO 1.5s running 11.3.1. It seems that machines that are running for quite some time with very active use eventually hang. I grabbed some longs from a Browse session, which seems to be the activity running when the crashes happen, but looking at the logs, it seems to be something failing at a lower level. See http://bugs.sugarlabs.org/ticket/3678 Also, at times, Restart fails to restart. -walter -- Walter Bender Sugar Labs http://www.sugarlabs.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On Sat, Jun 9, 2012 at 2:22 AM, Walter Bender walter.ben...@gmail.com wrote: On Tue, Jun 5, 2012 at 10:37 AM, Martin Langhoff mar...@laptop.org wrote: Hi folks, the Dextrose team has been hunting a bug on XO-1.5, on their variant of 11.3.x (Dextrose 3 or DX3), and they are pointing out that it could be a latent or unreported problem in 11.3.x series. It could also be a problem in their modifications. While they continue to investigate, it is important to hear whether anyone has seen XO-1.5s handing during shutdown, on the Warnings screen. - It seems to affect some units, not all. So far it has been seen on 3 units with SN starting with SHC037 . - Units affected show the symptoms 2 out of 5 boots. - Seems to be related to umount of /home failing. Adding sync ; sleep 2; before umount seems to cure it; that's their current workaround. - Their debugging adventures are documented at http://dev.laptop.org.au/issues/1033 - They will be checking whether the symptoms follow the microSD card or the motherboard, swapping microSD with a good unit. Why is this important? When the unit hangs during shutdown, it is left in a condition where it can overheat, potentially damaging the unit. The bottom line: have you seen this issue on XO-1.5 + 11.3.x? Even if ocassionally? Let us know, and join the bug-hunting party. cheers, m -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel While I haven't seen the exact symptoms described here, I have seen some problems here in Chachapoyas. XO 1.5s running 11.3.1. It seems that machines that are running for quite some time with very active use eventually hang. I grabbed some longs from a Browse session, which seems to be the activity running when the crashes happen, but looking at the logs, it seems to be something failing at a lower level. See http://bugs.sugarlabs.org/ticket/3678 Also, at times, Restart fails to restart. In our specific case (of this problem on an XO-1.5 running dx3), the hang was occurring even when almost no activity was done, i.e. start the XO, wait for sugar boot, shutdown the XO. -walter -- Walter Bender Sugar Labs http://www.sugarlabs.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel -- Anish | an...@sugarlabs.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
Hi folks, the Dextrose team has been hunting a bug on XO-1.5, on their variant of 11.3.x (Dextrose 3 or DX3), and they are pointing out that it could be a latent or unreported problem in 11.3.x series. It could also be a problem in their modifications. While they continue to investigate, it is important to hear whether anyone has seen XO-1.5s handing during shutdown, on the Warnings screen. - It seems to affect some units, not all. So far it has been seen on 3 units with SN starting with SHC037 . - Units affected show the symptoms 2 out of 5 boots. - Seems to be related to umount of /home failing. Adding sync ; sleep 2; before umount seems to cure it; that's their current workaround. - Their debugging adventures are documented at http://dev.laptop.org.au/issues/1033 - They will be checking whether the symptoms follow the microSD card or the motherboard, swapping microSD with a good unit. Why is this important? When the unit hangs during shutdown, it is left in a condition where it can overheat, potentially damaging the unit. The bottom line: have you seen this issue on XO-1.5 + 11.3.x? Even if ocassionally? Let us know, and join the bug-hunting party. cheers, m -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On Tue, Jun 5, 2012 at 10:37 AM, Martin Langhoff mar...@laptop.org wrote: - Seems to be related to umount of /home failing. Adding sync ; sleep 2; before umount seems to cure it; that's their current workaround. Cutting the CC list down to only devel@ for debugging -- Anish, thanks for reporting this. Couple of questions/requests: - can you give us the exact patch showing the workaround you are applying? - very interested in the microSD swap between good and bad units. Let us know how it goes. On 12.1.0 the switch to systemd completely reworks the shutdown / umount process; so if it affects Fedora or OLPC releases, the scope is 11.3.x / F14. Very unlikely that we see it, at least in this particular incarnation, on 12.1.0. cheers, m -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On 06/06/12 02:37, Martin Langhoff wrote: The bottom line: have you seen this issue on XO-1.5 + 11.3.x? Even if ocassionally? Let us know, and join the bug-hunting party. We have seen this sort of problem in Auckland recently. However I can't really be sure if what we see is related. We test XO-1.5s, XO-1.75s, 11.3.1, olpc-au's dextrose release and 12.1.0 and I don't recall which laptops and which releases have hung. We have seen a wide variety of shutdown misbehaviour, ranging from shutdown doesn't do anything at all through to everything appears to be off except the power light is on solid. We'll do some explicit testing of shutdown on Saturday. ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: On XO-1.5 with 11.3.0/11.3.1 -- hang during shutdown?
On Tue, Jun 5, 2012 at 4:43 PM, Tom Parker t...@carrott.org wrote: We'll do some explicit testing of shutdown on Saturday. Fantastic, thanks! m -- mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
