Re: [v6 PATCH] RISC-V: Remove unsupported isa string info print

From: Christoph Hellwig
Date: Tue Oct 01 2019 - 03:02:39 EST


On Mon, Sep 30, 2019 at 05:23:18PM -0700, Atish Patra wrote:
> /proc/cpuinfo should just print all the isa string as an information
> instead of determining what is supported or not. ELF hwcap can be
> used by the userspace to figure out that.
>
> Simplify the isa string printing by removing the unsupported isa string
> print and all related code.
>
> The relevant discussion can be found at
> http://lists.infradead.org/pipermail/linux-riscv/2019-September/006702.html

This looks good, but can you also rename the orig_isa argument to isa
now that we never modify it?

> /*
> * Linux doesn't support rv32e or rv128i, and we only support booting
> * kernels on harts with the same ISA that the kernel is compiled for.
> */
> #if defined(CONFIG_32BIT)
> - if (strncmp(isa, "rv32i", 5) != 0)
> + if (strncmp(orig_isa, "rv32i", 5) != 0)
> return;
> #elif defined(CONFIG_64BIT)
> - if (strncmp(isa, "rv64i", 5) != 0)
> + if (strncmp(orig_isa, "rv64i", 5) != 0)
> return;
> #endif

And I don't think having these checks here makes much sense. If we want
to check this at all we should do it somewhere in the boot process.