> Since I'm at least partially to blame for creation of this mailing list (I > asked > Andrew Morton for one at the CELF Conference), I thought I might as well > stir > things up by throwing a few features out there that I think would improve > the > Linux kernel for use in the embedded world: > > Crash Diagnostics > ----------------- > The single biggest thing we've encountered is the requirement for good > diagnostic > reports. We have a fat data pipe to our settop box, but the return pipe is > way > too small for kernel core dumps. As a result, we send failure reports that > consist of register and stack dumps for the kernel and current > application, > backtraces, etc. Even though some of the details are processor specific, > there > are changes we've made in the generic kernel to support doing this. These > will be > filtered out gradually as I get time to get them into shape to be > submitted. > > Continuous Logging for Watchdog Timer Expiration > ------------------------------------------------ > We run with a watchdog timer that can reboot the system. When we reboot, > we lose > all of our status, making it very difficult to determine what went wrong. > Fortunately, there is only one major cause of not refreshing the > watchdog--a > driver disabled interrupts for so long that the timer function that resets > the > watchdog timer never had a chance to run. So, a way to log what functions > were > enable and disabling interrupts on a continuous basis, along with a memory > section that wouldn't be overwritten on reboot, would allow capturing the > cause > for these otherwise "silent" reboots. > > NVM Filesystems (Separate Metadata?) > ------------------------------------ > NVM is generally too small to allow for the overhead of filesystem > metadata, but > being able to access and manage that data without regard for particular > allocation would be very useful. The good thing is that the data > allocation in > NVM is generally static, so data is overwritten but doesn't change size or > location. It would be nice to have some facility to have the metadata be > separately compiled and then to use the normal open/read/write/close > interfaces > to use the data. We presently manage allocations with a C header file, but > this > is awkward and error-prone. > > On-line Disk Partitioning > ------------------------- > Server and desktop systems partition their disks at installation time, but > some > applications require that partitioning be done after we are already using > a root > filesystem on disk. We only have one disk and the driver specifically > prevents > changing the partitioning while a disk partition is in use. Note that we > don't > want to change the root partition, just other partitions. This drives the > need > for some sort of on-line partitioning that allows changing partitions that > aren't > in use. > -- I've started an Embedded Linux Kernel WishList wiki page here: http://elinux.org/WishList > > -- > To unsubscribe from this list: send the line "unsubscribe linux-embedded" > in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
