Re: Finding a rogue src/sys commit with bisection?

On Sat, Nov 15, 2014 at 11:52:24AM -0700, Ian Lepore wrote:
> On Sat, 2014-11-15 at 10:43 -0800, Steve Kargl wrote:
> > Before I totally hose by /usr/src directory, does anyone
> > have some guidelines on doing a binary search for a rogue
> > commit in /usr/src/sys?.  Either cam or usb (or acpi?) has
> > broken the ability to remove a external USB device once it
> > is plugged into a usb port on my Dell Latitude D530 laptop.
> > I know that a good kernel can be built with r271273 and
> > a bad kernel comes from (nearly) top of tree at r274456.
> > 
> > I assume I need to do somthing along the lines
> > 
> > % cd /usr/src/sys
> > % svn merge -r 274456:272864    (half way point between good and bad)
> > (build kernel and test)
> > % cd /usr/src/sys
> > % svn revert -R .
> > (assume 272864 builds working kernel)
> > % svn merge -r 274456:273660   (1/2 point between 272864 and 274456).
> > 
> > Rinse and repeat.
> > 
> 
> I've always used 'svn up -rnnnnnn' to bisect.  No need to revert, just
> repeatedly update to the next halfway point, and when you're all done,
> -rHEAD to get back to normal.  I've also had very good results with
> using -DNO_CLEAN on kernel bisects, it lets you zoom in quickly then
> when you think you have a candidate you can do a more complete
> clean-and-rebuild to be sure.  Sometimes build glitches will require a
> clean rebuild at some bisect points.
> 

Ian, Thanks!  I, obviously, had not considered 'svn update' 
as a method to achieve what I wanti/need to do.

-- 
Steve