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Date:   Thu, 12 Aug 2021 00:18:34 -0700 (PDT)
Subject:     Re: [PATCH -fixes] riscv: Fix comment regarding kernel mapping overlapping with IS_ERR_VALUE
In-Reply-To: <20210726054254.21801-1-alex@ghiti.fr>
CC:     Paul Walmsley <paul.walmsley@sifive.com>, aou@eecs.berkeley.edu,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        alex@ghiti.fr
From:   Palmer Dabbelt <palmer@dabbelt.com>
To:     alex@ghiti.fr
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On Sun, 25 Jul 2021 22:42:54 PDT (-0700), alex@ghiti.fr wrote:
> The current comment states that we check if the 64-bit kernel mapping
> overlaps with the last 4K of the address space that is reserved to
> error values in create_kernel_page_table, which is not the case since it
> is done in setup_vm. But anyway, remove the reference to any function
> and simply note that in 64-bit kernel, the check should be done as soon
> as the kernel mapping base address is known.
>
> Fixes: db6b84a368b4 ("riscv: Make sure the kernel mapping does not
> overlap with IS_ERR_VALUE")
> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
> ---
>  arch/riscv/mm/init.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index a14bf3910eec..79a2e02924e4 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -191,7 +191,7 @@ static void __init setup_bootmem(void)
>  	 * if end of dram is equal to maximum addressable memory.  For 64-bit
>  	 * kernel, this problem can't happen here as the end of the virtual
>  	 * address space is occupied by the kernel mapping then this check must
> -	 * be done in create_kernel_page_table.
> +	 * be done as soon as the kernel mapping base address is determined.
>  	 */
>  	max_mapped_addr = __pa(~(ulong)0);
>  	if (max_mapped_addr == (dram_end - 1))

Thanks, this is on fixes.