Resolve this smatch warning:
arch/riscv/kernel/sys_hwprobe.c:50 hwprobe_arch_id() error: uninitialized symbol 'cpu_id'.
This could happen if hwprobe_arch_id() was called with a key ID of
something other than MVENDORID, MIMPID, and MARCHID. This does not
happen in the current codebase. The only caller of hwprobe_arch_id()
is a function that only passes one of those three key IDs.
For the sake of reducing static analyzer warning noise, and in the
unlikely event that hwprobe_arch_id() is someday called with some
other key ID, validate hwprobe_arch_id()'s input to ensure that
'cpu_id' is always initialized before use.
Fixes: ea3de9ce8a ("RISC-V: Add a syscall for HW probing")
Cc: Evan Green <evan@rivosinc.com>
Signed-off-by: Paul Walmsley <pjw@kernel.org>
Link: https://lore.kernel.org/r/cf5a13ec-19d0-9862-059b-943f36107bf3@kernel.org
b7776a802f