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charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20250711154423.GW1880847@ZenIV> X-Rspamd-Queue-Id: ED2331C000D X-Rspam-User: X-Rspamd-Server: rspam09 X-Stat-Signature: muh88n7s41dinenfx8zr9iky8yttmd6p X-HE-Tag: 1752472350-603482 X-HE-Meta: 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 vX54Zb6T 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: (+Luis for the usermode helper discussion) On Fri, Jul 11, 2025 at 04:44:23PM +0100, Al Viro wrote: > On Fri, Jul 11, 2025 at 12:35:59PM +0200, Thomas Weißschuh wrote: > > Hi Kees, Al, Christian and Honza, > > > > On Thu, Jun 26, 2025 at 08:10:14AM +0200, Thomas Weißschuh wrote: > > > The KUnit UAPI infrastructure starts userspace processes. > > > As it should be able to be built as a module, export the necessary symbols. > > What's wrong with kernel/umh.c? It gets neutered by CONFIG_STATIC_USERMODEHELPER_PATH. That could be worked around be overriding sub_info->path, but it would be a hack. It does not allow to implement a custom wait routine to forward the process output to KUnit as implemented in kunit_uapi_forward_to_printk() [0]. That may be solved by adding another thread, but that would also be hacky. It would probably be possible to extend kernel/umh.c for my usecase but I didn't want bloat the core kernel code for my test-only functionality. > > could you take a look at these new symbol exports? > > > > +EXPORT_SYMBOL_GPL_FOR_MODULES(put_filesystem, "kunit-uapi"); > > What's that one for??? What are you referring to? The macro EXPORT_SYMBOL_GPL_FOR_MODULES() will only export the symbol for one specific module. Personally I'm also fine with EXPORT_SYMBOL_GPL(). "kunit-uapi" is a new module I am implementing in this patchset. It allows to run userspace executables as part of KUnit. Some more information in the cover-letter [1] of the series and the code using these symbols[0]. Both should also be in your inbox. There is also an article on LWN [2]. [0] https://lore.kernel.org/lkml/20250626-kunit-kselftests-v4-12-48760534fef5@linutronix.de/ [1] https://lore.kernel.org/lkml/20250626-kunit-kselftests-v4-0-48760534fef5@linutronix.de/ [2] https://lwn.net/SubscriberLink/1029077/fa55c3b2d238a6bb/ Thomas