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McKenney" , Boqun Feng , Shuah Khan , Thomas Gleixner , linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH] selftests/rseq: Add config fragment Message-ID: References: <20260424-selftests-rseq-config-fragment-v1-1-fcf60116e690@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260424-selftests-rseq-config-fragment-v1-1-fcf60116e690@kernel.org> On Fri, Apr 24, 2026 at 12:16:22AM +0100, Mark Brown wrote: > Currently we do not provide a config fragment for the rseq selftests but > there are several options which are either required or helpful for > running them: > > - CONFIG_RSEQ is required for obvious reasons, it is enabled by default > but it doesn't hurt to specify it in case the user is usinsg a > defconfig that disables it. > > - CONFIG_RSEQ_DEBUG_DEFAULT_ENABLE turns on runtime debug checks which > would for example have helped spot some of the recent issues we've > seen on arm64: > > https://lore.kernel.org/all/87zf2u28d1.ffs@tglx/ > > - CONFIG_DEBUG_RSEQ enables debugging on configurations that don't have > generic entry support. > > - CONFIG_RSEQ_SLICE_EXTENSION is tested by the slice_test test, the > test will fail without it. > > Add a configuration fragment which enables these options, helping > encourage CI systems and people doing manual testing to run the tests > with all the features and additional checks. We also enable > CONFIG_DEBUG_KERNEL and CONFIG_EXPERT which are dependencies for these > options. As a heads-up, it might be worth waiting on the DEBUG bits for now given Linus's comment at: https://lore.kernel.org/linux-arm-kernel/CAHk-=wjsEqWJxXArS-P5+ksSY2Apaox8u6FtUrtyWSBEOL4Q2Q@mail.gmail.com/ i.e. | (a) the debug code in question needs to just be removed, since it's | now actively detrimental, and means that any kernel developer who | *does* enable it can't actually test this case any more. It's checking | for something that has been shown to not be true. ... but it probably makes sense to enable the SLICE_EXTENSION option if we have tests for that. Mark. > Signed-off-by: Mark Brown > --- > tools/testing/selftests/rseq/config | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/tools/testing/selftests/rseq/config b/tools/testing/selftests/rseq/config > new file mode 100644 > index 000000000000..d11b8c61530e > --- /dev/null > +++ b/tools/testing/selftests/rseq/config > @@ -0,0 +1,6 @@ > +CONFIG_DEBUG_KERNEL=y > +CONFIG_DEBUG_RSEQ=y > +CONFIG_EXPERT=y > +CONFIG_RSEQ=y > +CONFIG_RSEQ_DEBUG_DEFAULT_ENABLE=y > +CONFIG_RSEQ_SLICE_EXTENSION=y > > --- > base-commit: 2e68039281932e6dc37718a1ea7cbb8e2cda42e6 > change-id: 20260423-selftests-rseq-config-fragment-65f09caf0276 > > Best regards, > -- > Mark Brown >