Nicolas, On Fri, Dec 17 2021 at 11:57, Nicolas Saenz Julienne wrote: > +Non-instrumentable code - noinstr > +--------------------------------- > + > +Most instrumentation facilities depend on RCU, so intrumentation is prohibited > +for entry code before RCU starts watching and exit code after RCU stops > +watching. In addition, many architectures must save and restore register state, > +which means that (for example) a breakpoint in the breakpoint entry code would > +overwrite the debug registers of the initial breakpoint. > + > +Such code must be marked with the 'noinstr' attribute, placing that code into a > +special section inaccessible to instrumentation and debug facilities. Some > +functions are partially instrumentable, which is handled by marking them nointr s/nointr/noinstr/ Thanks for polishing this! tglx