Re: [PATCH v2] kconfig: Avoid prompting for transitional symbols

[Andrew Donnellan]

On Tue, 2025-09-30 at 08:45 -0700, Kees Cook wrote:
> The "transitional" symbol keyword, while working with the "olddefconfig"
> target, was prompting during "oldconfig". This occurred because these
> symbols were not being marked as user-defined when they received values
> from transitional symbols that had user values. The "olddefconfig" target
> explicitly doesn't prompt for anything, so this deficiency wasn't noticed.
> 
> The issue manifested when a symbol's value came from a transitional
> symbol's user value but the receiving symbol wasn't marked with
> SYMBOL_DEF_USER. Thus the "oldconfig" logic would then prompt for these
> symbols unnecessarily.
> 
> Check after value calculation whether a symbol without a user value
> gets its value from a single transitional symbol that does have a user
> value. In such cases, mark the receiving symbol as user-defined to
> prevent prompting.
> 
> Update regression tests to verify that symbols with transitional defaults
> are not prompted in "oldconfig", except when conditional defaults evaluate
> to 'no' and should legitimately be prompted.
> 
> Build tested with "make testconfig".
> 
> Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
> Closes:
> https://lore.kernel.org/lkml/CAHk-=wgZjUk4Cy2XgNkTrQoO8XCmNUHrTe5D519Fij1POK+3qw@xxxxxxxxxxxxxx/
> Fixes: 05020835c86e ("kconfig: Add transitional symbol attribute for migration
> support")

I think this should be f9afce4f32e9.

Andrew


-- 
Andrew Donnellan    OzLabs, ADL Canberra
ajd@xxxxxxxxxxxxx   IBM Australia Limited