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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.56.2 (3.56.2-2.fc42) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Tue, 2026-07-07 at 13:18 +0100, Matt Fleming wrote: > Hi Rik and Henrik, >=20 > I've got a small C reproducer that triggers this within the first > round > on Cloudflare's AMD Turin machines: >=20 > =C2=A0 https://gist.github.com/mfleming/ca26ad3f8d65a12d23d62fb176480fc1 >=20 > Build: >=20 > =C2=A0 gcc -O2 -Wall -Wextra -pthread -static -o repro-invlpgb repro- > invlpgb.c >=20 > Run: >=20 > =C2=A0 ./repro-invlpgb --batch --rounds 20 --jobs 32 -d 5 -w 8 -m 2 -s 51= 2 > -q >=20 Now that's interesting. I ran it for 100 rounds on a 158 core Turin system, without hitting the issue. I'll play around with it some more to see whether I can make it happen by varying the parameters, but now I'm also wondering whether hardware differences might be at play. --=20 All Rights Reversed.