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References: <20230503-virt-to-pfn-v6-4-rc1-v1-0-6c4698dcf9c8@linaro.org> <20230503-virt-to-pfn-v6-4-rc1-v1-2-6c4698dcf9c8@linaro.org>
In-Reply-To: <20230503-virt-to-pfn-v6-4-rc1-v1-2-6c4698dcf9c8@linaro.org>
From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Fri, 12 May 2023 11:55:55 +0200
Message-ID: <CAMuHMdVJjjo9TMeow1-i27ybpQOu9-VZYnTkY5p8p_Cm6sW_GA@mail.gmail.com>
Subject: Re: [PATCH 02/12] m68k: Pass a pointer to virt_to_pfn() virt_to_page()
To:     Linus Walleij <linus.walleij@linaro.org>
Cc:     Vineet Gupta <vgupta@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
        Russell King <linux@armlinux.org.uk>,
        Greg Ungerer <gerg@linux-m68k.org>,
        linux-kernel@vger.kernel.org, linux-m68k@lists.linux-m68k.org,
        linux-snps-arc@lists.infradead.org, linux-fsdevel@vger.kernel.org,
        linux-cifs@vger.kernel.org, samba-technical@lists.samba.org,
        linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org
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Hi Linus,

On Thu, May 11, 2023 at 1:59 PM Linus Walleij <linus.walleij@linaro.org> wrote:
> Functions that work on a pointer to virtual memory such as
> virt_to_pfn() and users of that function such as
> virt_to_page() are supposed to pass a pointer to virtual
> memory, ideally a (void *) or other pointer. However since
> many architectures implement virt_to_pfn() as a macro,
> this function becomes polymorphic and accepts both a
> (unsigned long) and a (void *).
>
> Fix up the offending calls in arch/m68k with explicit casts.
>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
> ChangeLog v1->v2:
> - Add an extra parens around the page argument to the
>   PD_PTABLE() macro, as is normally required.

Thanks for the update!

To build sun3_defconfig and m5475evb_defconfig cleanly, you need to
include the (Gmail-whitespace-damaged) changes below.
These were compile-tested only.

diff --git a/arch/m68k/include/asm/mcf_pgtable.h
b/arch/m68k/include/asm/mcf_pgtable.h
index 96d069829803505c..46ae379bb14d5e05 100644
--- a/arch/m68k/include/asm/mcf_pgtable.h
+++ b/arch/m68k/include/asm/mcf_pgtable.h
@@ -135,7 +135,7 @@ static inline void pte_clear(struct mm_struct *mm,
unsigned long addr,
 }

 #define pte_pagenr(pte)        ((__pte_page(pte) - PAGE_OFFSET) >> PAGE_SHIFT)
-#define pte_page(pte)  virt_to_page(__pte_page(pte))
+#define pte_page(pte)  virt_to_page((void *)__pte_page(pte))

 static inline int pmd_none2(pmd_t *pmd) { return !pmd_val(*pmd); }
 #define pmd_none(pmd) pmd_none2(&(pmd))
diff --git a/arch/m68k/include/asm/sun3_pgtable.h
b/arch/m68k/include/asm/sun3_pgtable.h
index e582b0484a55cd82..f3e7728f58cd9dd0 100644
--- a/arch/m68k/include/asm/sun3_pgtable.h
+++ b/arch/m68k/include/asm/sun3_pgtable.h
@@ -109,9 +109,9 @@ static inline void pte_clear (struct mm_struct
*mm, unsigned long addr, pte_t *p
 #define pfn_pte(pfn, pgprot) \
 ({ pte_t __pte; pte_val(__pte) = pfn | pgprot_val(pgprot); __pte; })

-#define pte_page(pte)          virt_to_page(__pte_page(pte))
+#define pte_page(pte)          virt_to_page((void *)__pte_page(pte))
 #define pmd_pfn(pmd)           (pmd_val(pmd) >> PAGE_SHIFT)
-#define pmd_page(pmd)          virt_to_page(pmd_page_vaddr(pmd))
+#define pmd_page(pmd)          virt_to_page((void *)pmd_page_vaddr(pmd))


 static inline int pmd_none2 (pmd_t *pmd) { return !pmd_val (*pmd); }
diff --git a/arch/m68k/mm/mcfmmu.c b/arch/m68k/mm/mcfmmu.c
index 70aa0979e02710a8..a4c552c7e2c8ca12 100644
--- a/arch/m68k/mm/mcfmmu.c
+++ b/arch/m68k/mm/mcfmmu.c
@@ -69,7 +69,7 @@ void __init paging_init(void)

                /* now change pg_table to kernel virtual addresses */
                for (i = 0; i < PTRS_PER_PTE; ++i, ++pg_table) {
-                       pte_t pte = pfn_pte(virt_to_pfn(address), PAGE_INIT);
+                       pte_t pte = pfn_pte(virt_to_pfn((void
*)address), PAGE_INIT);
                        if (address >= (unsigned long) high_memory)
                                pte_val(pte) = 0;

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds