From nobody Tue Jul 7 14:36:20 2026 Received: from mail-wm1-f73.google.com (mail-wm1-f73.google.com [209.85.128.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 016E0233959 for ; Wed, 24 Jun 2026 12:32:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782304354; cv=none; b=C1IxYUaYi3Yfl18/iiZ/CBIMnlb9Kl8fST7qPmIauY0Onh5m6+2djsd3Nmz+uw8s49KcBkydeCamk9TbCe4Gq89sSGXKrfWULyQP3y7wAAvRXkaXphj1AGzUSBX/Xko4H1zLqBJvwYyslHTWU7gHghDu7lymr8bwRQvcnDrXAhk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782304354; c=relaxed/simple; bh=5FrcuFrgqBxEbfLy3QuVu/KjPYnuB4FIdwKxZQ62HY0=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=Dw+kopfL+eoKQOnKX84qZxNksI25AQEKbiD2sE5xnczeqCed8EZCy3ohwD+7/AX3PPWkUZLU8qh2PP5rZD/r3XpsRmmcAJSH+fKVU+TWGz/Y3/stwbIkoK6Nhcsyopghi+VyeO/pWRm9NL86wBkrlFSZlW7dBm8i4lJtuFD3Sfc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jackmanb.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=KSIa3f4C; arc=none smtp.client-ip=209.85.128.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--jackmanb.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="KSIa3f4C" Received: by mail-wm1-f73.google.com with SMTP id 5b1f17b1804b1-4924207e640so5876775e9.3 for ; Wed, 24 Jun 2026 05:32:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1782304351; x=1782909151; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=p/xEtfmGVkRQAAmE8iX0NGb5qu8SoC9YnyiG7cjEHg8=; b=KSIa3f4C32dBKIPL+YBkkYpvjakCaONBrxE2fQnOl5ICh3C0XFIs9YWbDcZg4rZq2u GNSSxo0JkslBmHc5i/r4qdA+IqEeyV5VMHvPV3AXAu/qDoNsZCF7xN7kC8Gu1+fC3SbQ B/VdIizTXwcicSEFXYPkI+mFrl5r9jJ9KnATL1s1cjVCdIa7S2M7HbZdCzTwdskVirzn njA4rX11N/qSo2Wd0u8oWDs7ZR4ZvkxS6bDfUZBxJBU0hkxs2jE24V0c4mEfYd7YfREI UvKLQWG+23x2HY4zIRK6GTaDNiDsqhKE73XP34N5qVFB75+dMQtLSjuRJOP5lUJOavBR 5F8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782304351; x=1782909151; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=p/xEtfmGVkRQAAmE8iX0NGb5qu8SoC9YnyiG7cjEHg8=; b=Nl41QugsnaQ45rnpwayLvU6hQmTddIWpbgB+i8iC9Rl8MH+M9D9lzDfWf7owsC55Fn o/NG3AqxG1ATYRDhT39dtUfJ9C4ghZLdswwlso2GCgI3vVaU0a5Uv8FK7oTMIoqpSJ6f 8lToPO4fQ+KQURFlxu439NFSK+IngV7w3HuzHl1IStv/M+6a6xyi29cUh9WV9cNpUZRG V71BqGfr11kQQkZbcCLSBgCsDw0Z4rZqb4JQF+8V3uAuUZHblXn408i5SKcFFh5o5qsi HLT1qjo1q3JgygQqNqi6/P9FzAX8oRmJmBYLkHetHSrMxV0O3jR8jE7gSSAgoMAk9KzL 4sbQ== X-Gm-Message-State: AOJu0Yx6ExjGHlbHhKtDP7Eq71tGZlj4XKw/2fJlofcg3RYcZoMoK5dw D9jvy9Z6ISsM0Jh2lNTziqIz8venW4Pwmgqc5ykCTtgZmlz4K0YukTlwR3k78cqHpoU0RubRQnc ieZ6aJM+p32r8Gw== X-Received: from wrge11.prod.google.com ([2002:a05:6000:178b:b0:453:508e:615a]) (user=jackmanb job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:3113:b0:48a:5565:ec3d with SMTP id 5b1f17b1804b1-492490a790cmr268746035e9.22.1782304350937; Wed, 24 Jun 2026 05:32:30 -0700 (PDT) Date: Wed, 24 Jun 2026 12:32:15 +0000 In-Reply-To: <20260624-x86-init-cleanup-v3-0-b13de1f82366@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260624-x86-init-cleanup-v3-0-b13de1f82366@google.com> X-Mailer: b4 0.15.2 Message-ID: <20260624-x86-init-cleanup-v3-1-b13de1f82366@google.com> Subject: [PATCH v3 1/4] x86/mm: drop unused return from init_memory_mapping() From: Brendan Jackman To: Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Marcel Busch , brendan.jackman@linux.dev Cc: linux-kernel@vger.kernel.org, Brendan Jackman Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable None of the callers look at the return value. Reviewed-by: Marcel Busch Tested-by: Marcel Busch Reviewed-by: Dave Hansen Signed-off-by: Brendan Jackman --- arch/x86/include/asm/pgtable.h | 3 +-- arch/x86/mm/init.c | 16 +++++++--------- 2 files changed, 8 insertions(+), 11 deletions(-) diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index ac295ca6c92f9..96dd7aa699c86 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -1170,8 +1170,7 @@ extern int direct_gbpages; void init_mem_mapping(void); void early_alloc_pgt_buf(void); void __init poking_init(void); -unsigned long init_memory_mapping(unsigned long start, - unsigned long end, pgprot_t prot); +void init_memory_mapping(unsigned long start, unsigned long end, pgprot_t = prot); =20 #ifdef CONFIG_X86_64 extern pgd_t trampoline_pgd_entry; diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index fb67217fddcd3..ae3e9e0820153 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -531,11 +531,11 @@ bool pfn_range_is_mapped(unsigned long start_pfn, uns= igned long end_pfn) * This runs before bootmem is initialized and gets pages directly from * the physical memory. To access them they are temporarily mapped. */ -unsigned long __ref init_memory_mapping(unsigned long start, - unsigned long end, pgprot_t prot) +void __ref init_memory_mapping(unsigned long start, + unsigned long end, pgprot_t prot) { struct map_range mr[NR_RANGE_MR]; - unsigned long ret =3D 0; + unsigned long paddr_last =3D 0; int nr_range, i; =20 pr_debug("init_memory_mapping: [mem %#010lx-%#010lx]\n", @@ -545,13 +545,11 @@ unsigned long __ref init_memory_mapping(unsigned long= start, nr_range =3D split_mem_range(mr, 0, start, end); =20 for (i =3D 0; i < nr_range; i++) - ret =3D kernel_physical_mapping_init(mr[i].start, mr[i].end, - mr[i].page_size_mask, - prot); + paddr_last =3D kernel_physical_mapping_init(mr[i].start, mr[i].end, + mr[i].page_size_mask, + prot); =20 - add_pfn_range_mapped(start >> PAGE_SHIFT, ret >> PAGE_SHIFT); - - return ret >> PAGE_SHIFT; + add_pfn_range_mapped(start >> PAGE_SHIFT, paddr_last >> PAGE_SHIFT); } =20 /* --=20 2.54.0 From nobody Tue Jul 7 14:36:20 2026 Received: from mail-ed1-f73.google.com (mail-ed1-f73.google.com [209.85.208.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3E41126ED46 for ; 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Wed, 24 Jun 2026 05:32:32 -0700 (PDT) Date: Wed, 24 Jun 2026 12:32:16 +0000 In-Reply-To: <20260624-x86-init-cleanup-v3-0-b13de1f82366@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260624-x86-init-cleanup-v3-0-b13de1f82366@google.com> X-Mailer: b4 0.15.2 Message-ID: <20260624-x86-init-cleanup-v3-2-b13de1f82366@google.com> Subject: [PATCH v3 2/4] x86/mm: simplify calculation of max_pfn_mapped From: Brendan Jackman To: Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Marcel Busch , brendan.jackman@linux.dev Cc: linux-kernel@vger.kernel.org, Brendan Jackman Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The phys_*_init()s return the "last physical address mapped". The exact definition of this is pretty fiddly, but only in these conditions: 1. There is a mismatch between the alignment of the requested range and the page sizes allowed by page_size_mask. For init_memory_mapping(), this is guaranteed by split_mem_range(), whose job is to set the correct page_size_mask for each returned range. 2. The range ends in a region that was already mapped. This case is particularly fiddly because the return value depends on what level the existing mapping is at. This is probably a bug, see [0] for discussion. Luckily, the callers of init_memory_mapping() all operate on distinct regions and only call it at most once for any given range. So, just lean on this caller behaviour and make it a precondition for calling init_memory_mapping(). Thus, deliberately avoid relying on the probably-broken return value. [0]: https://lore.kernel.org/all/84b2e7a3-7115-45fe-89ff-db8ee46729f2@intel= .com/ Reviewed-by: Marcel Busch Tested-by: Marcel Busch Signed-off-by: Brendan Jackman --- arch/x86/mm/init.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index ae3e9e0820153..1c9e6d8ebb8d7 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -530,6 +530,8 @@ bool pfn_range_is_mapped(unsigned long start_pfn, unsig= ned long end_pfn) * Setup the direct mapping of the physical memory at PAGE_OFFSET. * This runs before bootmem is initialized and gets pages directly from * the physical memory. To access them they are temporarily mapped. + * + * Call this function at most once for any given range. */ void __ref init_memory_mapping(unsigned long start, unsigned long end, pgprot_t prot) @@ -545,10 +547,10 @@ void __ref init_memory_mapping(unsigned long start, nr_range =3D split_mem_range(mr, 0, start, end); =20 for (i =3D 0; i < nr_range; i++) - paddr_last =3D kernel_physical_mapping_init(mr[i].start, mr[i].end, - mr[i].page_size_mask, - prot); + kernel_physical_mapping_init(mr[i].start, mr[i].end, + mr[i].page_size_mask, prot); =20 + paddr_last =3D mr[nr_range - 1].end; add_pfn_range_mapped(start >> PAGE_SHIFT, paddr_last >> PAGE_SHIFT); } =20 --=20 2.54.0 From nobody Tue Jul 7 14:36:20 2026 Received: from mail-ej1-f74.google.com (mail-ej1-f74.google.com [209.85.218.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AAB1E214A9B for ; Wed, 24 Jun 2026 12:32:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.74 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782304357; cv=none; b=qP4dGkGM9sQFDQ++vqbmsywZhwua2EQ9MxbMoEU84sybIz8cBHrNxoJJRsEnFWyALi5Xkmhabi5RMxmWwtyNddmHP7yBHyjIdAX5bR+r8PQnD3vW4kXLIPymN9JPR5LjIRE8PAyOOV5D2oOKxx+4SKD1224FDL8Pmp/WLr4GY9k= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782304357; c=relaxed/simple; bh=Iwi/Ny9EE1bnQun1LbdX1mi9gte78a7G1yYwHyzb6yA=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=fXYvFXup5vTIoG2CcyYZDZfq/Dx0HjEawuw0OgrgqEcSr2VyFzvecpj8KyHjxiFLxZ9I7eUsCFbi5p4qLBWcDKQo/g4PvqDfT7ccaBsEaDj1J3AKG0tmjRHvtrL86eMJnHSyddsxjwHqUFyTeaMRNwNY01NSQg54HM+TKaZWYMA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jackmanb.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=L8k8oJXB; arc=none smtp.client-ip=209.85.218.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--jackmanb.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="L8k8oJXB" Received: by mail-ej1-f74.google.com with SMTP id a640c23a62f3a-c0829064d2bso68185766b.0 for ; Wed, 24 Jun 2026 05:32:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1782304354; x=1782909154; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=cVjBry0bQEIB7C7nEWC+C6YLCUb/aB0prJxA13bx5xE=; b=L8k8oJXBC52jOJcQuKekr+x7xxsnviYVPOdN5mOFWsYgVqggsrSpQj9k0+UlbfHoTC dbHEi6gbRLsk+1WFUiA1y/QiK++m9Gjrdt+wQs8flFh4se00pHHg10D7Fk5sbVpEQLpH BX7ffboQBqt8+qVCn3T5kv29mg5byrhAl6Rrx9rVAnRPkBGf0FS/el5UAiOH6DNRSYfK +msGhhgdLYtH0CXwowqYWz0XSiNmJnmTX5N5szn30BNQwzVErCWx3LBXqUI+zhzbrDLA 9qIIUyM7NPpCIK8/2e5OtLHfXbBrs+ccJnONQ6qFT68EVK4Pqe3P7QxxJ/D3mIXKB7Ht wCfg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782304354; x=1782909154; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=cVjBry0bQEIB7C7nEWC+C6YLCUb/aB0prJxA13bx5xE=; b=Gw/HSod8kly6ouSivtqSUTYfYz6wu7biy/QOjyYKrNsWNJKFh2sq6xyVLAiUgtCZNQ l5r8RE/MK9riBPPkpfYZG6ucLACUBo7yWx+5wt2pgoVthyjrRftwli8YSSJmhmldYHgu h8WxPyKlM/owHj0m1/ID20TnIyHXqBBTd+QR2Ms4J5YBZEGkLav8Mxn5UqQF2FHV8gJ3 X9OJ1WXpQmX+kcdHw3wDNRztxn2y0ghohSgdD/89MgbXvo3eTNzNhvfoTvFox4TlrFJH GszVkl5qWoUv4zASC2mPbmlUtXPg5HsP2Gahno1yszhRGITDg0SMT/UOMfVmw68NpkLk CcfA== X-Gm-Message-State: AOJu0Yy+kuNnphcb/PcfO6sT0jzLpl8xM0fbssaSeAlmPcoXYzi/szfj paqnDo1MQnIVLsALkaGxprxGtlnwHYMEpsHl227n/iygE1bIlF97TTYj+DZklgy6e6LPQQZEVAX 3vGCiZWoJPVS7fQ== X-Received: from ejfu12.prod.google.com ([2002:a17:906:3b8c:b0:beb:dabe:3536]) (user=jackmanb job=prod-delivery.src-stubby-dispatcher) by 2002:a17:907:9309:b0:c08:28f5:e767 with SMTP id a640c23a62f3a-c107d10bfe7mr469872066b.15.1782304353465; Wed, 24 Jun 2026 05:32:33 -0700 (PDT) Date: Wed, 24 Jun 2026 12:32:17 +0000 In-Reply-To: <20260624-x86-init-cleanup-v3-0-b13de1f82366@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260624-x86-init-cleanup-v3-0-b13de1f82366@google.com> X-Mailer: b4 0.15.2 Message-ID: <20260624-x86-init-cleanup-v3-3-b13de1f82366@google.com> Subject: [PATCH v3 3/4] x86/mm: drop unused returns from direct map setup functions From: Brendan Jackman To: Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Marcel Busch , brendan.jackman@linux.dev Cc: linux-kernel@vger.kernel.org, Brendan Jackman Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Nothing looks at these return values. Furthermore, as discussed in [0], it seems like in the case of a pre-existing 4K mapping, the return value of kernel_physical_mapping_init() is wrong anyway. So, just stop returning a value. Reviewed-by: Marcel Busch Tested-by: Marcel Busch Reviewed-by: Dave Hansen Signed-off-by: Brendan Jackman --- arch/x86/mm/init_32.c | 5 +-- arch/x86/mm/init_64.c | 96 ++++++++++++++++---------------------------= ---- arch/x86/mm/mm_internal.h | 11 ++---- 3 files changed, 38 insertions(+), 74 deletions(-) diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 0908c44d51e6f..05c456dc9855f 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -245,14 +245,13 @@ static inline int is_x86_32_kernel_text(unsigned long= addr) * of max_low_pfn pages, by creating page tables starting from address * PAGE_OFFSET: */ -unsigned long __init +void __init kernel_physical_mapping_init(unsigned long start, unsigned long end, unsigned long page_size_mask, pgprot_t prot) { int use_pse =3D page_size_mask =3D=3D (1<> PAGE_SHIFT, prot), init); - paddr_last =3D (paddr & PAGE_MASK) + PAGE_SIZE; } =20 update_page_count(PG_LEVEL_4K, pages); - - return paddr_last; } =20 /* * Create PMD level page table mapping for physical addresses. The virtual * and physical address have to be aligned at this level. - * It returns the last physical address mapped. */ -static unsigned long __meminit +static void __meminit phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_en= d, unsigned long page_size_mask, pgprot_t prot, bool init) { unsigned long pages =3D 0, paddr_next; - unsigned long paddr_last =3D paddr_end; =20 int i =3D pmd_index(paddr); =20 @@ -548,9 +539,7 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, uns= igned long paddr_end, if (!pmd_leaf(*pmd)) { spin_lock(&init_mm.page_table_lock); pte =3D (pte_t *)pmd_page_vaddr(*pmd); - paddr_last =3D phys_pte_init(pte, paddr, - paddr_end, prot, - init); + phys_pte_init(pte, paddr, paddr_end, prot, init); spin_unlock(&init_mm.page_table_lock); continue; } @@ -569,7 +558,6 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, uns= igned long paddr_end, if (page_size_mask & (1 << PG_LEVEL_2M)) { if (!after_bootmem) pages++; - paddr_last =3D paddr_next; continue; } new_prot =3D pte_pgprot(pte_clrhuge(*(pte_t *)pmd)); @@ -582,33 +570,29 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, u= nsigned long paddr_end, pfn_pmd(paddr >> PAGE_SHIFT, prot_sethuge(prot)), init); spin_unlock(&init_mm.page_table_lock); - paddr_last =3D paddr_next; continue; } =20 pte =3D alloc_low_page(); - paddr_last =3D phys_pte_init(pte, paddr, paddr_end, new_prot, init); + phys_pte_init(pte, paddr, paddr_end, new_prot, init); =20 spin_lock(&init_mm.page_table_lock); pmd_populate_kernel_init(&init_mm, pmd, pte, init); spin_unlock(&init_mm.page_table_lock); } update_page_count(PG_LEVEL_2M, pages); - return paddr_last; } =20 /* * Create PUD level page table mapping for physical addresses. The virtual * and physical address do not have to be aligned at this level. KASLR can * randomize virtual addresses up to this level. - * It returns the last physical address mapped. */ -static unsigned long __meminit +static void __meminit phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_en= d, unsigned long page_size_mask, pgprot_t _prot, bool init) { unsigned long pages =3D 0, paddr_next; - unsigned long paddr_last =3D paddr_end; unsigned long vaddr =3D (unsigned long)__va(paddr); int i =3D pud_index(vaddr); =20 @@ -634,10 +618,8 @@ phys_pud_init(pud_t *pud_page, unsigned long paddr, un= signed long paddr_end, if (!pud_none(*pud)) { if (!pud_leaf(*pud)) { pmd =3D pmd_offset(pud, 0); - paddr_last =3D phys_pmd_init(pmd, paddr, - paddr_end, - page_size_mask, - prot, init); + phys_pmd_init(pmd, paddr, paddr_end, + page_size_mask, prot, init); continue; } /* @@ -655,7 +637,6 @@ phys_pud_init(pud_t *pud_page, unsigned long paddr, uns= igned long paddr_end, if (page_size_mask & (1 << PG_LEVEL_1G)) { if (!after_bootmem) pages++; - paddr_last =3D paddr_next; continue; } prot =3D pte_pgprot(pte_clrhuge(*(pte_t *)pud)); @@ -668,13 +649,11 @@ phys_pud_init(pud_t *pud_page, unsigned long paddr, u= nsigned long paddr_end, pfn_pud(paddr >> PAGE_SHIFT, prot_sethuge(prot)), init); spin_unlock(&init_mm.page_table_lock); - paddr_last =3D paddr_next; continue; } =20 pmd =3D alloc_low_page(); - paddr_last =3D phys_pmd_init(pmd, paddr, paddr_end, - page_size_mask, prot, init); + phys_pmd_init(pmd, paddr, paddr_end, page_size_mask, prot, init); =20 spin_lock(&init_mm.page_table_lock); pud_populate_init(&init_mm, pud, pmd, init); @@ -682,23 +661,22 @@ phys_pud_init(pud_t *pud_page, unsigned long paddr, u= nsigned long paddr_end, } =20 update_page_count(PG_LEVEL_1G, pages); - - return paddr_last; } =20 -static unsigned long __meminit +static void __meminit phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_en= d, unsigned long page_size_mask, pgprot_t prot, bool init) { - unsigned long vaddr, vaddr_end, vaddr_next, paddr_next, paddr_last; + unsigned long vaddr, vaddr_end, vaddr_next, paddr_next; =20 - paddr_last =3D paddr_end; vaddr =3D (unsigned long)__va(paddr); vaddr_end =3D (unsigned long)__va(paddr_end); =20 - if (!pgtable_l5_enabled()) - return phys_pud_init((pud_t *) p4d_page, paddr, paddr_end, - page_size_mask, prot, init); + if (!pgtable_l5_enabled()) { + phys_pud_init((pud_t *) p4d_page, paddr, paddr_end, + page_size_mask, prot, init); + return; + } =20 for (; vaddr < vaddr_end; vaddr =3D vaddr_next) { p4d_t *p4d =3D p4d_page + p4d_index(vaddr); @@ -720,33 +698,30 @@ phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, u= nsigned long paddr_end, =20 if (!p4d_none(*p4d)) { pud =3D pud_offset(p4d, 0); - paddr_last =3D phys_pud_init(pud, paddr, __pa(vaddr_end), - page_size_mask, prot, init); + phys_pud_init(pud, paddr, __pa(vaddr_end), + page_size_mask, prot, init); continue; } =20 pud =3D alloc_low_page(); - paddr_last =3D phys_pud_init(pud, paddr, __pa(vaddr_end), - page_size_mask, prot, init); + phys_pud_init(pud, paddr, __pa(vaddr_end), + page_size_mask, prot, init); =20 spin_lock(&init_mm.page_table_lock); p4d_populate_init(&init_mm, p4d, pud, init); spin_unlock(&init_mm.page_table_lock); } - - return paddr_last; } =20 -static unsigned long __meminit +static void __meminit __kernel_physical_mapping_init(unsigned long paddr_start, unsigned long paddr_end, unsigned long page_size_mask, pgprot_t prot, bool init) { bool pgd_changed =3D false; - unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last; + unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next; =20 - paddr_last =3D paddr_end; vaddr =3D (unsigned long)__va(paddr_start); vaddr_end =3D (unsigned long)__va(paddr_end); vaddr_start =3D vaddr; @@ -759,16 +734,14 @@ __kernel_physical_mapping_init(unsigned long paddr_st= art, =20 if (pgd_val(*pgd)) { p4d =3D (p4d_t *)pgd_page_vaddr(*pgd); - paddr_last =3D phys_p4d_init(p4d, __pa(vaddr), - __pa(vaddr_end), - page_size_mask, - prot, init); + phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end), + page_size_mask, prot, init); continue; } =20 p4d =3D alloc_low_page(); - paddr_last =3D phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end), - page_size_mask, prot, init); + phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end), + page_size_mask, prot, init); =20 spin_lock(&init_mm.page_table_lock); if (pgtable_l5_enabled()) @@ -783,8 +756,6 @@ __kernel_physical_mapping_init(unsigned long paddr_star= t, =20 if (pgd_changed) sync_global_pgds(vaddr_start, vaddr_end - 1); - - return paddr_last; } =20 =20 @@ -792,15 +763,15 @@ __kernel_physical_mapping_init(unsigned long paddr_st= art, * Create page table mapping for the physical memory for specific physical * addresses. Note that it can only be used to populate non-present entrie= s. * The virtual and physical addresses have to be aligned on PMD level - * down. It returns the last physical address mapped. + * down. */ -unsigned long __meminit +void __meminit kernel_physical_mapping_init(unsigned long paddr_start, unsigned long paddr_end, unsigned long page_size_mask, pgprot_t prot) { - return __kernel_physical_mapping_init(paddr_start, paddr_end, - page_size_mask, prot, true); + __kernel_physical_mapping_init(paddr_start, paddr_end, + page_size_mask, prot, true); } =20 /* @@ -809,14 +780,13 @@ kernel_physical_mapping_init(unsigned long paddr_star= t, * when updating the mapping. The caller is responsible to flush the TLBs = after * the function returns. */ -unsigned long __meminit +void __meminit kernel_physical_mapping_change(unsigned long paddr_start, unsigned long paddr_end, unsigned long page_size_mask) { - return __kernel_physical_mapping_init(paddr_start, paddr_end, - page_size_mask, PAGE_KERNEL, - false); + __kernel_physical_mapping_init(paddr_start, paddr_end, + page_size_mask, PAGE_KERNEL, false); } =20 #ifndef CONFIG_NUMA diff --git a/arch/x86/mm/mm_internal.h b/arch/x86/mm/mm_internal.h index 7c4a41235323b..dad8abe65ed03 100644 --- a/arch/x86/mm/mm_internal.h +++ b/arch/x86/mm/mm_internal.h @@ -10,13 +10,10 @@ static inline void *alloc_low_page(void) =20 void early_ioremap_page_table_range_init(void); =20 -unsigned long kernel_physical_mapping_init(unsigned long start, - unsigned long end, - unsigned long page_size_mask, - pgprot_t prot); -unsigned long kernel_physical_mapping_change(unsigned long start, - unsigned long end, - unsigned long page_size_mask); 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Wed, 24 Jun 2026 05:32:34 -0700 (PDT) Date: Wed, 24 Jun 2026 12:32:18 +0000 In-Reply-To: <20260624-x86-init-cleanup-v3-0-b13de1f82366@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260624-x86-init-cleanup-v3-0-b13de1f82366@google.com> X-Mailer: b4 0.15.2 Message-ID: <20260624-x86-init-cleanup-v3-4-b13de1f82366@google.com> Subject: [PATCH v3 4/4] x86/mm: delete unnecessary arg from split_mem_range() From: Brendan Jackman To: Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Marcel Busch , brendan.jackman@linux.dev Cc: linux-kernel@vger.kernel.org, Brendan Jackman Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable This function is only called from one place, where the arg is zero i.e. the struct map_range[] is cleared. Since there's no usecase for "appending" ranges just delete the argument. Signed-off-by: Brendan Jackman --- arch/x86/mm/init.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 1c9e6d8ebb8d7..0fc489d52874d 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -398,12 +398,13 @@ static const char *page_size_string(struct map_range = *mr) return str_4k; } =20 -static int __meminit split_mem_range(struct map_range *mr, int nr_range, +static int __meminit split_mem_range(struct map_range *mr, unsigned long start, unsigned long end) { unsigned long start_pfn, end_pfn, limit_pfn; unsigned long pfn; + int nr_range =3D 0; int i; =20 limit_pfn =3D PFN_DOWN(end); @@ -544,7 +545,7 @@ void __ref init_memory_mapping(unsigned long start, start, end - 1); =20 memset(mr, 0, sizeof(mr)); - nr_range =3D split_mem_range(mr, 0, start, end); + nr_range =3D split_mem_range(mr, start, end); =20 for (i =3D 0; i < nr_range; i++) kernel_physical_mapping_init(mr[i].start, mr[i].end, --=20 2.54.0