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Howlett" , Uros Bizjak , Thomas =?utf-8?Q?Wei=C3=9Fschuh?= , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, kernel-dev@igalia.com Subject: Re: [PATCH RFC v2 0/2] arm64: vdso: Implement __vdso_futex_robust_try_unlock() Message-ID: <20260428110054.oQNT-kMn@linutronix.de> References: <20260424-tonyk-robust_arm-v2-0-db4e46f752cf@igalia.com> Precedence: bulk X-Mailing-List: linux-arch@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <20260424-tonyk-robust_arm-v2-0-db4e46f752cf@igalia.com> On 2026-04-24 15:55:59 [-0300], Andr=C3=A9 Almeida wrote: > Hi folks, Hi, > This is my take on implementing the new vDSO for unlocking a robust futex= in > arm64. If you don't know what's that, Thomas wrote a good summary, > including the motivation for this work and the x86 implementation: >=20 > https://lore.kernel.org/lkml/878qb89g7b.ffs@tglx/ >=20 > There are some loose ends in my patchset so I'm sending as a RFC to ask > some questions: >=20 > - If the process is interrupted between the labels, we need to check the > conditional flags and clear the op_pending address from the register. Us= ing > objdump I see that op_pending addr is being stored at x2, but I suspect = that > this isn't stable, so I need to figure out how to make sure that the add= ress > will always be stored in the same register. > - So far I have implemented only the LL/SC version to make review easier= , but I > can do the LSE version as well. I am a bit behind here. In the meantime, were you able to check it with https://lore.kernel.org/all/20260404093939.7XgeW_54@linutronix.de/ ? Sebastian