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AJvYcCWcdemwLXjZmVItwYpD1zf+ub+JSTHZWQRdVuS7eT7I/wmxOwJBbRFI/5j+s2n5ctsQnBDDL8IxXOI=@vger.kernel.org X-Gm-Message-State: AOJu0YzMUrlK94+k4X0MNW+EXgoTWRFmsGIWa2mFM+QHFlhdggnhZHcm sdjblFw7nxEFVlwxgzD9Ekh9gAD+6bl82bQNf4F7UeKKZ/9MeGun60G0gj/m7U1X7K/4mlSfSVG Zon+E0B5WAWTeEA== X-Google-Smtp-Source: AGHT+IGBA2lpZUSLCjfeKNqH37XEkgRmaFO7ZPXyGAUePy8kb9MXP5eNENudc2tbx+F3YPjQ8UIPJq3fcamnSg== X-Received: from wmbgx15.prod.google.com ([2002:a05:600c:858f:b0:477:e0a:f99e]) (user=jackmanb job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:3e06:b0:475:dc58:39e5 with SMTP id 5b1f17b1804b1-4773089b541mr1846735e9.27.1761839381266; Thu, 30 Oct 2025 08:49:41 -0700 (PDT) Date: Thu, 30 Oct 2025 15:49:40 +0000 In-Reply-To: <20251030-b4-prctl-docs-2-v1-1-396645cb8d61@google.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251030-b4-prctl-docs-2-v1-1-396645cb8d61@google.com> X-Mailer: aerc 0.21.0 Message-ID: Subject: Re: [PATCH] Documentation/x86: Fix PR_SET_SPECULATION_CTRL error codes From: Brendan Jackman To: Brendan Jackman , Jonathan Corbet , Thomas Gleixner , Borislav Petkov , Peter Zijlstra , Josh Poimboeuf , Pawan Gupta , Balbir Singh , , , Content-Type: text/plain; charset="UTF-8" On Thu Oct 30, 2025 at 1:59 PM UTC, Brendan Jackman wrote: > -ENXIO Control of the selected speculation misfeature is not possible. > - See PR_GET_SPECULATION_CTRL. > +ENXIO For PR_SPEC_STORE_BYPASS: control of the selected speculation misfeature > + is not possible via prctl, because of the system's boot configuration. > + > +EPERM Speculation was disabled with PR_SPEC_FORCE_DISABLE and caller tried to > + enable it again. > + > +EPERM For PR_SPEC_STORE_BYPASS and PR_SPEC_INDIRECT_BRANCH: control of the Ugh, ^^^^^^^^^^^^^^^^^^^^ that should be PR_SPEC_L1D_FLUSH I will wait a day or two before v2 in case anyone else spots other mistakes or has other comments.