Hi Greg, On 2018/11/22 21:23, Greg Kroah-Hartman wrote: > On Thu, Nov 22, 2018 at 09:01:31PM +0800, Gao Xiang wrote: >> Hi Greg, >> >> On 2018/11/22 20:00, Gao Xiang wrote: >>> Hi Greg, >>> >>> On 2018/11/22 19:26, Greg Kroah-Hartman wrote: >>>> Don't make people rebuild your code with different options for >>>> debugging. That will never work in the 'real world' when people start >>>> using the code. You need to have things enabled for people all the >>>> time, which is why we have dynamic debugging in the kernel now, and not >>>> a zillion different "DRIVER_DEBUG" build options anymore. >>> Actually, current erofs handle differently for beta users (in eng mode) >>> and commercial users. >>> >>> CONFIG_EROFS_FS_DEBUG is enable for all beta users, after an observed >>> expression is false, we could get the whole memorydump as early as possible. >>> But for commercial users, there are no such observing points to promise >>> the kernel stability and performance. >>> >>> It has helped us to find several bug, and I cannot find some alternative way >>> to get the the first scene of the accident... >> >> I'm about to send v2 of this patchset... I need to get your opinion... >> >> I think for the current erofs development state, I tend to leave such a >> developping switch because the code could be modified frequently, >> many potential bugs could be avoid when this debugging mode is on and >> it will be dropped after erofs becomes more stable... > > You have two competing issues here. You need to have some sort of debug > build that allows you to get feedback from users, and you need to > provide a solid, reliable system for those not wanting to debug > anything. Yes, you are right :) > > If you use a kernel build option, then you can do what you are doing > now, just that do not expect for any user that has problems with the > filesystem, they will rebuild the code just to try to help debug it. > That is going to require run-time debugging to be enabled as they will > not usually have built their own kernel/module at all. Yes, actually the current Android system have 2 modes -- eng and commerical build for all versions. A large number of beta users will receive eng build, and many buges were observed from these users. That is the debugging benefit what Android system does now. I do not expect real users to rebuild kernels for debugging, I think after the Android use case, erofs has become solid enough. For commerical builds, it will have enough error handing case found by Android users and developers. > > For now, keep doing what you are doing, I just started to worry when I > saw the initial BUG_ON() as we had just talked about these at the > Maintainers summit a few weeks ago, and how we need to get rid of them > from the kernel as they are a crutch that we need to solve. Thanks for understanding... Thanks, Gao Xiang > > thanks, and sorry for the noise. Please resend this series again, > > greg k-h > _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
