| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <76ec40af-d234-400a-af0f-faeb001c9182@lucifer.local>
Date: Tue, 2 Sep 2025 07:19:58 +0100
From: Lorenzo Stoakes <lorenzo.stoakes@...cle.com>
To: Max Kellermann <max.kellermann@...os.com>
Cc: akpm@...ux-foundation.org, david@...hat.com, axelrasmussen@...gle.com,
yuanchu@...gle.com, willy@...radead.org, hughd@...gle.com,
mhocko@...e.com, linux-kernel@...r.kernel.org, linux-mm@...ck.org,
Liam.Howlett@...cle.com, vbabka@...e.cz, rppt@...nel.org,
surenb@...gle.com, vishal.moola@...il.com, linux@...linux.org.uk,
James.Bottomley@...senpartnership.com, deller@....de,
agordeev@...ux.ibm.com, gerald.schaefer@...ux.ibm.com,
hca@...ux.ibm.com, gor@...ux.ibm.com, borntraeger@...ux.ibm.com,
svens@...ux.ibm.com, davem@...emloft.net, andreas@...sler.com,
dave.hansen@...ux.intel.com, luto@...nel.org, peterz@...radead.org,
tglx@...utronix.de, mingo@...hat.com, bp@...en8.de, x86@...nel.org,
hpa@...or.com, chris@...kel.net, jcmvbkbc@...il.com,
viro@...iv.linux.org.uk, brauner@...nel.org, jack@...e.cz,
weixugc@...gle.com, baolin.wang@...ux.alibaba.com, rientjes@...gle.com,
shakeel.butt@...ux.dev, thuth@...hat.com, broonie@...nel.org,
osalvador@...e.de, jfalempe@...hat.com, mpe@...erman.id.au,
nysal@...ux.ibm.com, linux-arm-kernel@...ts.infradead.org,
linux-parisc@...r.kernel.org, linux-s390@...r.kernel.org,
sparclinux@...r.kernel.org, linux-fsdevel@...r.kernel.org
Subject: Re: [PATCH v6 00/12] mm: establish const-correctness for pointer
parameters
On Mon, Sep 01, 2025 at 10:50:09PM +0200, Max Kellermann wrote:
> For improved const-correctness in the low-level memory-management
> subsystem, which provides a basis for further const-ification further
> up the call stack (e.g. filesystems).
Great, this succinctly expresses what you want!
>
> This patch series splitted into smaller patches was initially posted
> as a single large patch:
>
> https://lore.kernel.org/lkml/20250827192233.447920-1-max.kellermann@ionos.com/
>
> I started this work when I tried to constify the Ceph filesystem code,
> but found that to be impossible because many "mm" functions accept
> non-const pointer, even though they modify nothing.
And as Vlasta said, this is great context.
>
> Signed-off-by: Max Kellermann <max.kellermann@...os.com>
Glad we got there in the end :) hopefully having more const-ification will have
a knock-on effect anyway for future development both by:
a. People needing to ensure it downstream of this stuff &.
b. Seeing the pattern and adopting it.
So this should have a positive impact I think :)
Cheers, Lorenzo
> ---
> v1 -> v2:
> - made several parameter values const (i.e. the pointer address, not
> just the pointed-to memory), as suggested by Andrew Morton and
> Yuanchu Xie
> - drop existing+obsolete "extern" keywords on lines modified by these
> patches (suggested by Vishal Moola)
> - add missing parameter names on lines modified by these patches
> (suggested by Vishal Moola)
> - more "const" pointers (e.g. the task_struct passed to
> process_shares_mm())
> - add missing "const" to s390, fixing s390 build failure
> - moved the mmap_is_legacy() change in arch/s390/mm/mmap.c from 08/12
> to 06/12 (suggested by Vishal Moola)
>
> v2 -> v3:
> - remove garbage from 06/12
> - changed tags on subject line (suggested by Matthew Wilcox)
>
> v3 -> v4:
> - more verbose commit messages including a listing of function names
> (suggested by David Hildenbrand and Lorenzo Stoakes)
>
> v4 -> v5:
> - back to shorter commit messages after an agreement between David
> Hildenbrand and Lorenzo Stoakes was found
>
> v5 -> v6:
> - fix inconsistent constness of assert_fault_locked()
> - revert the const parameter value change from v2 (requested by
> Lorenzo Stoakes)
> - revert the long cover letter, removing long explanations again
> (requested by Lorenzo Stoakes)
>
> Max Kellermann (12):
> mm: constify shmem related test functions for improved
> const-correctness
> mm: constify pagemap related test/getter functions
> mm: constify zone related test/getter functions
> fs: constify mapping related test functions for improved
> const-correctness
> mm: constify process_shares_mm() for improved const-correctness
> mm, s390: constify mapping related test/getter functions
> parisc: constify mmap_upper_limit() parameter
> mm: constify arch_pick_mmap_layout() for improved const-correctness
> mm: constify ptdesc_pmd_pts_count() and folio_get_private()
> mm: constify various inline functions for improved const-correctness
> mm: constify assert/test functions in mm.h
> mm: constify highmem related functions for improved const-correctness
>
> arch/arm/include/asm/highmem.h | 6 +--
> arch/parisc/include/asm/processor.h | 2 +-
> arch/parisc/kernel/sys_parisc.c | 2 +-
> arch/s390/mm/mmap.c | 6 +--
> arch/sparc/kernel/sys_sparc_64.c | 2 +-
> arch/x86/mm/mmap.c | 6 +--
> arch/xtensa/include/asm/highmem.h | 2 +-
> include/linux/fs.h | 6 +--
> include/linux/highmem-internal.h | 36 +++++++++---------
> include/linux/highmem.h | 8 ++--
> include/linux/mm.h | 56 +++++++++++++--------------
> include/linux/mm_inline.h | 25 ++++++------
> include/linux/mm_types.h | 4 +-
> include/linux/mmzone.h | 42 ++++++++++----------
> include/linux/pagemap.h | 59 +++++++++++++++--------------
> include/linux/sched/mm.h | 4 +-
> include/linux/shmem_fs.h | 4 +-
> mm/highmem.c | 10 ++---
> mm/oom_kill.c | 6 +--
> mm/shmem.c | 6 +--
> mm/util.c | 16 ++++----
> 21 files changed, 155 insertions(+), 153 deletions(-)
>
> --
> 2.47.2
>
Powered by blists - more mailing lists