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Message-ID: <876d3cd5-bb99-edd0-47c0-6dc34c8402d1@ghiti.fr>
Date:   Wed, 20 Sep 2023 11:14:09 +0200
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Subject: Re: [PATCH v3 3/3] riscv: Introduce NAPOT field to PTDUMP
Content-Language: en-US
To:     Yu Chien Peter Lin <peterlin@andestech.com>,
        paul.walmsley@sifive.com, palmer@dabbelt.com,
        aou@eecs.berkeley.edu, david@redhat.com, akpm@linux-foundation.org,
        alexghiti@rivosinc.com, bjorn@rivosinc.com,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org
Cc:     conor.dooley@microchip.com
References: <20230920035522.3180558-1-peterlin@andestech.com>
 <20230920035522.3180558-3-peterlin@andestech.com>
From:   Alexandre Ghiti <alex@ghiti.fr>
In-Reply-To: <20230920035522.3180558-3-peterlin@andestech.com>
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On 20/09/2023 05:55, Yu Chien Peter Lin wrote:
> This patch introduces the NAPOT field to PTDUMP, allowing it
> to display the letter "N" for pages that have the 63rd bit set.
>
> Signed-off-by: Yu Chien Peter Lin <peterlin@andestech.com>
> ---
> Changes v1 -> v3
> - no change
> ---
>   arch/riscv/mm/ptdump.c | 4 ++++
>   1 file changed, 4 insertions(+)
>
> diff --git a/arch/riscv/mm/ptdump.c b/arch/riscv/mm/ptdump.c
> index 13997cf3fe36..b71f08b91e53 100644
> --- a/arch/riscv/mm/ptdump.c
> +++ b/arch/riscv/mm/ptdump.c
> @@ -136,6 +136,10 @@ struct prot_bits {
>   static const struct prot_bits pte_bits[] = {
>   	{
>   #ifdef CONFIG_64BIT
> +		.mask = _PAGE_NAPOT,
> +		.set = "N",
> +		.clear = ".",
> +	}, {
>   		.mask = _PAGE_MTMASK_SVPBMT,
>   		.set = "MT(%s)",
>   		.clear = "  ..  ",

Nice to see that we actually transparently use napot mappings:

---[ PCI I/O start ]---
0xffff8d7fff000000-0xffff8d7fff010000    0x0000000003000000 64K PTE N   
..     ..   D A G . . W R V

You can add:

Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>

Tested-by: Alexandre Ghiti <alexghiti@rivosinc.com>

Thanks for the series, really appreciated!

Alex