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Wysocki" Subject: Re: Linux 6.18 Message-ID: References: <93259f2b-7017-4096-a31b-cabbf6152e9b@roeck-us.net> 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: On Mon, Dec 01, 2025 at 10:01:24PM -0800, Guenter Roeck wrote: > On 12/1/25 20:50, Brian Norris wrote: > > On Mon, Dec 01, 2025 at 06:39:49PM -0800, Guenter Roeck wrote: > > > Looks like that fails pretty much on every architecture/platform where > > > it is enabled. Copying the author (Brian) for feedback. > > > > I wonder how you manage to be the one who hits all these problems, > > because none of the configurations and environments generated by > > ./tools/testing/kunit/kunit.py seem to hit it naturally. (I tested > > hundreds of cycles in various configurations with no failures > > previously, and I still didn't reproduce it today.) Do you make special > > effort to direct cosmic rays into your test setups while holding an > > unlucky charm? :) > > > > Neither cosmic rays nor unlucky charm needed (or at least so I hope ;-). > > I build the tests into the kernel and run them while booting in qemu. > Most other testbeds run the tests as module after booting and/or > on native machines (not in qemu). That makes a significant difference > in both behavior and timing. ./tools/testing/kunit/kunit.py runs with either user-mode Linux or QEMU, with tests built into the kernel and run while booting. That sounds rather similar to what you run. Previously, the main unique thing I recalled from your test setups was that you run a much wider array of ARCHes than I can manage. But that doesn't seem relevant, per your "pretty much every architecture" note. Obviously, race conditions are a bit environment / luck dependent, but I'm just surprised that when it *sounds* like we run something similar, you get near-100% failure, and I get 0%. *shrug* Brian