On Sun, Apr 19, 2026 at 05:54:23PM -0700, Kevin Bowling wrote: > Hi Nick, > > My understanding is we are trying to capture a 64-bit PC from the > kernel into a structure that n32 userland reads. If we sign extend a > 32-bit value read from the kernel, I'm not sure if we'd have the right > value in every case but I don't fully grasp the sign extension. I > suppose we'd need to understand some other cases like x86 user on > amd64 or sparc on sparc64 too, and KASLR?
Why is the kernel PC relevant here? I thought this would sample the userland PC as observed by the kernel, and for 32bit userland processes this can always only be a 32bit value (on sparc and i386 zero extended, on mips and riscv probably sign extended). Martin
