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Howlett" , Lorenzo Stoakes , Vlastimil Babka , Jann Horn , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Nathan Chancellor , Peter Zijlstra , Miguel Ojeda , Nicolas Schier , Thomas Gleixner , =?UTF-8?Q?Thomas_Wei=C3=9Fschuh?= , Alice Ryhl , Douglas Anderson , Gary Guo , Anand Moon , Randy Dunlap , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org References: <20260703022507.187457-1-leon.hwang@linux.dev> <8f75dc18-dd4c-4989-a76c-eec6cc513ccf@linux.dev> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Leon Hwang In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: AE67C14000A X-Stat-Signature: 44ssq96oho6inawd3j4r7ktoi5rqr77m X-HE-Tag: 1783432103-209437 X-HE-Meta: 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 R9xSVJRH jyjTJc++FRjjvmltdRM7RwD0ij6i5yGb262783Xsb4q72OyT3Akp2svNL0Ib84hCuCVmWOVsxOQdad6kpG1inSTbIRQVE0XmQ7uJLra9xgXbC0M5nWyrao+TftJwxJqJT0SAupVRT/oRa8XPupV6RHaU4WzW9dr9u+UjcJL9Vzm9m8082RjiISn64/0JTrzT2mji0tJTMCiZ+O8mQeVyuj1YWm+tNfca6Ap65/ptR5udP6itdlxqsY0EawyiMR/Z2zmdjBVyQ+qnNy8FxbIB0R/xHQeG85qiWJSvT Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2026/7/7 18:01, Pedro Falcato wrote: > On Fri, Jul 03, 2026 at 10:50:29PM +0800, Leon Hwang wrote: >> On 2026/7/3 17:44, Pedro Falcato wrote: [...] >>> >>>> >>>> The following architectures currently support this feature: x86-64, arm64, >>>> - loongarch and s390. >>>> + loongarch, riscv, and s390. >>> >>> This is also useless, every 64-bit architecture will support this. >> >> >> Do you mean dropping this sentence, or this change? > > This sentence (this is not architecture specific...). Got it. > >> >>> >>>> >>>> WARNING: This feature breaks programs which rely on relocating >>>> or unmapping system mappings. Known broken software at the time >>>> diff --git a/init/Kconfig b/init/Kconfig >>>> index 5230d4879b1c..12bb39f637b1 100644 >>>> --- a/init/Kconfig >>>> +++ b/init/Kconfig >>>> @@ -2112,7 +2112,7 @@ config ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS >>>> from a kernel perspective. >>>> >>>> After the architecture enables this, a distribution can set >>>> - CONFIG_MSEAL_SYSTEM_MAPPING to manage access to the feature. >>>> + CONFIG_MSEAL_SYSTEM_MAPPINGS to manage access to the feature. >>>> >>>> For complete descriptions of memory sealing, please see >>>> Documentation/userspace-api/mseal.rst >>>> diff --git a/mm/mseal.c b/mm/mseal.c >>>> index 9781647483d1..0464c7b94ab9 100644 >>>> --- a/mm/mseal.c >>>> +++ b/mm/mseal.c >>>> @@ -132,8 +132,8 @@ static int mseal_apply(struct mm_struct *mm, >>>> * addr is not a valid address (not allocated). >>>> * end (start + len) is not a valid address. >>>> * a gap (unallocated memory) between start and end. >>>> - * -EPERM: >>>> - * - In 32 bit architecture, sealing is not supported. >>>> + * -EINTR: >>>> + * interrupted while waiting for the mmap write lock. >>>> * Note: >>>> * user can call mseal(2) multiple times, adding a seal on an >>>> * already sealed memory is a no-action (no error). >>> >>> And this whole header needs to be deleted as well. No one's looking at >>> kernel code for documentation (and if they are, we did a horrendous job >>> at actually documenting the thing). >>> >> >> Just to confirm, do you mean removing the entire function comment above >> do_mseal()? > > Yes. Again, not your fault, just old gripes :) > Got it. Thanks, Leon