Re: [PATCH v3 1/2] Documentation: Fill the gaps about entry/noinstr constraints

[Thomas Gleixner]

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