Linux-mm Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: Sang-Heon Jeon <ekffu200098@gmail.com>
To: rppt@kernel.org, Albert Ou <aou@eecs.berkeley.edu>,
	Andrew Morton <akpm@linux-foundation.org>,
	Andrey Ryabinin <ryabinin.a.a@gmail.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Huacai Chen <chenhuacai@kernel.org>,
	Madhavan Srinivasan <maddy@linux.ibm.com>,
	Michael Ellerman <mpe@ellerman.id.au>,
	Muchun Song <muchun.song@linux.dev>,
	Oscar Salvador <osalvador@suse.de>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Paul Walmsley <pjw@kernel.org>,
	Russell King <linux@armlinux.org.uk>,
	Will Deacon <will@kernel.org>
Cc: linux-mm@kvack.org, Sang-Heon Jeon <ekffu200098@gmail.com>,
	Alexander Potapenko <glider@google.com>,
	Alexandre Ghiti <alex@ghiti.fr>,
	Andrey Konovalov <andreyknvl@gmail.com>,
	"Christophe Leroy (CS GROUP)" <chleroy@kernel.org>,
	David Hildenbrand <david@kernel.org>,
	Dmitry Vyukov <dvyukov@google.com>,
	kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
	linux-riscv@lists.infradead.org, loongarch@lists.linux.dev,
	Nicholas Piggin <npiggin@gmail.com>,
	Vincenzo Frascino <vincenzo.frascino@arm.com>,
	WANG Xuerui <kernel@xen0n.name>
Subject: [PATCH v3 0/8] treewide: remove unnecessary invalid range checks in memblock iteration loops
Date: Wed,  1 Jul 2026 00:04:05 +0900	[thread overview]
Message-ID: <20260630150413.1718632-1-ekffu200098@gmail.com> (raw)

The memblock API guarantees that for_each_mem_range() and
for_each_mem_pfn_range() never return an invalid range, meaning start is
always less than end.

Several memblock callers still have unnecessary invalid range checks in
their loop bodies, so remove them.

Patches 1-6 cover for_each_mem_range() callers. memblock never stores a
zero-size region, so the range it returns always has start < end. Some
callers apply __va() or __phys_to_virt() before comparing, but these keep
start < end too, so the check is unreachable.

Patches 7-8 cover for_each_mem_pfn_range() callers. __next_mem_pfn_range()
skips any region that contains no whole page, so it only ever returns
start_pfn < end_pfn and the check is unnecessary.

For reference, commit 36ca7f4be809 ("arm64: mm: Remove bogus stop
condition from map_mem() loop") did a similar cleanup in arm64 map_mem().

All these checks are in different trees, so I split the change into one
patch per arch/subsystem. The patches are independent and can be applied
separately.

---
Changes from v1 [1]
- Add review-by, tested-by tags from v1
- Add missing simliar patches(5,6) to patch series
- Change base to rppt/for-next

Changes from v2 [2]
- Remove unused local variable and braces

[1] https://lore.kernel.org/all/20260621145919.1453-1-ekffu200098@gmail.com/
[2] https://lore.kernel.org/all/20260629163736.1606688-1-ekffu200098@gmail.com/
---

Sang-Heon Jeon (8):
  arm64: mm: remove unreachable invalid range check in
    kasan_init_shadow()
  LoongArch: remove unreachable invalid range check in kasan_init()
  riscv: remove unreachable invalid range check in
    create_linear_mapping_page_table()
  riscv: remove unreachable invalid range check in kasan_init()
  ARM: remove unreachable invalid range check in kasan_init()
  powerpc64/kasan: Remove unreachable invalid range check in
    kasan_init_phys_region()
  mm: remove unnecessary empty range check in
    early_calculate_totalpages()
  mm/hugetlb: remove unnecessary empty range check in
    hugetlb_bootmem_set_nodes()

 arch/arm/mm/kasan_init.c               | 6 ------
 arch/arm64/mm/kasan_init.c             | 3 ---
 arch/loongarch/mm/kasan_init.c         | 3 ---
 arch/powerpc/mm/kasan/init_book3e_64.c | 3 ---
 arch/powerpc/mm/kasan/init_book3s_64.c | 3 ---
 arch/riscv/mm/init.c                   | 2 --
 arch/riscv/mm/kasan_init.c             | 3 ---
 mm/hugetlb.c                           | 7 ++-----
 mm/mm_init.c                           | 3 +--
 9 files changed, 3 insertions(+), 30 deletions(-)

-- 
2.43.0



             reply	other threads:[~2026-06-30 15:04 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-06-30 15:04 Sang-Heon Jeon [this message]
2026-06-30 15:04 ` [PATCH v3 1/8] arm64: mm: remove unreachable invalid range check in kasan_init_shadow() Sang-Heon Jeon
2026-06-30 15:04 ` [PATCH v3 2/8] LoongArch: remove unreachable invalid range check in kasan_init() Sang-Heon Jeon
2026-06-30 15:04 ` [PATCH v3 3/8] riscv: remove unreachable invalid range check in create_linear_mapping_page_table() Sang-Heon Jeon
2026-06-30 15:04 ` [PATCH v3 4/8] riscv: remove unreachable invalid range check in kasan_init() Sang-Heon Jeon
2026-06-30 15:04 ` [PATCH v3 5/8] ARM: " Sang-Heon Jeon
2026-06-30 15:04 ` [PATCH v3 6/8] powerpc64/kasan: Remove unreachable invalid range check in kasan_init_phys_region() Sang-Heon Jeon
2026-06-30 15:04 ` [PATCH v3 7/8] mm: remove unnecessary empty range check in early_calculate_totalpages() Sang-Heon Jeon
2026-06-30 15:04 ` [PATCH v3 8/8] mm/hugetlb: remove unnecessary empty range check in hugetlb_bootmem_set_nodes() Sang-Heon Jeon

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260630150413.1718632-1-ekffu200098@gmail.com \
    --to=ekffu200098@gmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=alex@ghiti.fr \
    --cc=andreyknvl@gmail.com \
    --cc=aou@eecs.berkeley.edu \
    --cc=catalin.marinas@arm.com \
    --cc=chenhuacai@kernel.org \
    --cc=chleroy@kernel.org \
    --cc=david@kernel.org \
    --cc=dvyukov@google.com \
    --cc=glider@google.com \
    --cc=kasan-dev@googlegroups.com \
    --cc=kernel@xen0n.name \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=linux@armlinux.org.uk \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=loongarch@lists.linux.dev \
    --cc=maddy@linux.ibm.com \
    --cc=mpe@ellerman.id.au \
    --cc=muchun.song@linux.dev \
    --cc=npiggin@gmail.com \
    --cc=osalvador@suse.de \
    --cc=palmer@dabbelt.com \
    --cc=pjw@kernel.org \
    --cc=rppt@kernel.org \
    --cc=ryabinin.a.a@gmail.com \
    --cc=vincenzo.frascino@arm.com \
    --cc=will@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox