Re: [PATCH v3 0/6] Enable strict percpu address space checks

On Sun,  8 Dec 2024 21:45:15 +0100 Uros Bizjak [off-list ref] wrote:

Enable strict percpu address space checks via x86 named address space
qualifiers. Percpu variables are declared in __seg_gs/__seg_fs named
AS and kept named AS qualified until they are dereferenced via percpu
accessor. This approach enables various compiler checks for
cross-namespace variable assignments.

Please note that current version of sparse doesn't know anything about
__typeof_unqual__() operator. Avoid the usage of __typeof_unqual__()
when sparse checking is active to prevent sparse errors with unknowing
keyword. The proposed patch by Dan Carpenter to implement
__typeof_unqual__() handling in sparse is located at:

google("what the hell is typeof_unequal") failed me.

I think it would be nice to include within the changelog (and code
comments!) an explanation-for-others of what this thing is and why
anyone would want to use it.  Rather than assuming that all kernel
developers are typeof() experts!