From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id CDDEF37DEB7; Tue, 28 Apr 2026 14:33:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777386811; cv=none; b=YGCYYU7WiadWif8NsKZeoQ6Fe+I/lkm5XjcFKZBPsZsfztGGR1P5OhWLvhjR1uT2+OAgHa8PG7MJY6zHETeFY2F8RQd55camY4IgZBq01qaF35gJ+bY/iggxGGG8sggbPl9qAzSBXt91G5lzgYsI23gDh1M0MX0mCddMBCVnZUg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777386811; c=relaxed/simple; bh=3Tjsh0Mi9ttoZCdrFqo6Hf9TG+BdK8gmbIDZCKmHfgI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=OfjP0rRe57JvQ83Osp8TkmR41ND1XdpaaQz3y7NX3rBXweqmyWItSqpUvQLLwQxKi7zgSsYLCpuZkpVeLdLq/qVhz6qevW0qlkJLQV7jC7Sad5nlpgahB7aDG4TCLSKTc/LxQIKh2vLo/95sr5gwJ1xTKPlZJ01z0qNfq+zCjJo= ARC-Authentication-Results:i=1; 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h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=czB/0boF7tK8yvbH/uwt6i6voyaRFSIx9N4QyPaWFgVEyb2orx+Vk61PNatG0TFgm ogtob/NZKbg0T6W56P7AkgMXiOjJEJk2WgzMT7ZfaSimH7G7SbXx6uQWVbXLqpg89p a5zADVDui8oYggRNAMTOAwua68gAwueUcc+dzheM= Message-ID: <666f0251-773b-4c71-9c68-5d0791297e31@arm.com> Date: Tue, 28 Apr 2026 16:33:25 +0200 Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 06/15] arm64: mm: Drop redundant pgd_t* argument from map_mem() To: Ard Biesheuvel , linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, will@kernel.org, catalin.marinas@arm.com, mark.rutland@arm.com, Ard Biesheuvel , Ryan Roberts , Anshuman Khandual , Liz Prucka , Seth Jenkins , Kees Cook , Mike Rapoport , David Hildenbrand , Andrew Morton , linux-mm@kvack.org, linux-hardening@vger.kernel.org References: <20260427153416.2103979-17-ardb+git@google.com> <20260427153416.2103979-23-ardb+git@google.com> From: Kevin Brodsky Content-Language: en-GB In-Reply-To: <20260427153416.2103979-23-ardb+git@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 27/04/2026 17:34, Ard Biesheuvel wrote: > From: Ard Biesheuvel > > __map_memblock() and map_mem() always operate on swapper_pg_dir, so > there is no need to pass around a pgd_t pointer between them. > > Reviewed-by: Ryan Roberts > Signed-off-by: Ard Biesheuvel Reviewed-by: Kevin Brodsky > --- > arch/arm64/mm/mmu.c | 25 ++++++++++---------- > 1 file changed, 12 insertions(+), 13 deletions(-) > > diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c > index bfbf3fe0d1be..9610dd2d7bd9 100644 > --- a/arch/arm64/mm/mmu.c > +++ b/arch/arm64/mm/mmu.c > @@ -1039,11 +1039,11 @@ static void update_mapping_prot(phys_addr_t phys, unsigned long virt, > flush_tlb_kernel_range(virt, virt + size); > } > > -static void __init __map_memblock(pgd_t *pgdp, phys_addr_t start, > - phys_addr_t end, pgprot_t prot, int flags) > +static void __init __map_memblock(phys_addr_t start, phys_addr_t end, > + pgprot_t prot, int flags) > { > - early_create_pgd_mapping(pgdp, start, __phys_to_virt(start), end - start, > - prot, early_pgtable_alloc, flags); > + early_create_pgd_mapping(swapper_pg_dir, start, __phys_to_virt(start), > + end - start, prot, early_pgtable_alloc, flags); > } > > void __init mark_linear_text_alias_ro(void) > @@ -1091,13 +1091,13 @@ static phys_addr_t __init arm64_kfence_alloc_pool(void) > return kfence_pool; > } > > -static void __init arm64_kfence_map_pool(phys_addr_t kfence_pool, pgd_t *pgdp) > +static void __init arm64_kfence_map_pool(phys_addr_t kfence_pool) > { > if (!kfence_pool) > return; > > /* KFENCE pool needs page-level mapping. */ > - __map_memblock(pgdp, kfence_pool, kfence_pool + KFENCE_POOL_SIZE, > + __map_memblock(kfence_pool, kfence_pool + KFENCE_POOL_SIZE, > pgprot_tagged(PAGE_KERNEL), > NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS); > memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE); > @@ -1133,11 +1133,11 @@ bool arch_kfence_init_pool(void) > #else /* CONFIG_KFENCE */ > > static inline phys_addr_t arm64_kfence_alloc_pool(void) { return 0; } > -static inline void arm64_kfence_map_pool(phys_addr_t kfence_pool, pgd_t *pgdp) { } > +static inline void arm64_kfence_map_pool(phys_addr_t kfence_pool) { } > > #endif /* CONFIG_KFENCE */ > > -static void __init map_mem(pgd_t *pgdp) > +static void __init map_mem(void) > { > static const u64 direct_map_end = _PAGE_END(VA_BITS_MIN); > phys_addr_t kernel_start = __pa_symbol(_text); > @@ -1182,7 +1182,7 @@ static void __init map_mem(pgd_t *pgdp) > * if MTE is present. Otherwise, it has the same attributes as > * PAGE_KERNEL. > */ > - __map_memblock(pgdp, start, end, pgprot_tagged(PAGE_KERNEL), > + __map_memblock(start, end, pgprot_tagged(PAGE_KERNEL), > flags); > } > > @@ -1196,10 +1196,9 @@ static void __init map_mem(pgd_t *pgdp) > * Note that contiguous mappings cannot be remapped in this way, > * so we should avoid them here. > */ > - __map_memblock(pgdp, kernel_start, kernel_end, > - PAGE_KERNEL, NO_CONT_MAPPINGS); > + __map_memblock(kernel_start, kernel_end, PAGE_KERNEL, NO_CONT_MAPPINGS); > memblock_clear_nomap(kernel_start, kernel_end - kernel_start); > - arm64_kfence_map_pool(early_kfence_pool, pgdp); > + arm64_kfence_map_pool(early_kfence_pool); > } > > void mark_rodata_ro(void) > @@ -1421,7 +1420,7 @@ static void __init create_idmap(void) > > void __init paging_init(void) > { > - map_mem(swapper_pg_dir); > + map_mem(); > > memblock_allow_resize(); >