[Bug target/124021] Interrupt function may clobber vstart on riscv

[bergner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124021

--- Comment #5 from Peter Bergner <bergner at gcc dot gnu.org> ---
(In reply to Peter Bergner from comment #3)
> This is confusing to me.

Offline, Jeff mentioned this isn't a userland issue running on Linux, but more
of a low-level kernel/firmware function.  Maybe richi's idea of disabling
vector is the right solution???