From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793714197; b=X79ObV2qnfjNq4Wsu/aXd09m+4a/5zBSLUE/SR/Q+RGJDiANn7J9DT2DcZBPXP4v/Kme IvO9cGz5Qf7RQSPkku8rSOSYufD2DXdVBqVFBetb3IYMoyNWV0baII4LpizqOpgIOyG6z aCNHGS5vL9wASKUPK5Bm2dzknPmFDUgv8s+iMFZOJlMfRWJHT8IdjYLWNimSwQFIsP8pd frSQf+Xq2iUDge2VuJ8V+ylw8yLQEghjC17O9++6FAg/EXaQsV9ewdawRzaFfGAdJPPmK Z05K4v43qxHcHn+7qbZDGxAvOV3jn68p4HVTdeAKTP71IcGilR5B6FNG2tdtRaaZpxg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793714197; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To: X-Cookie; bh=R+Lz59YAmE39OMTr2JsinbD50rhC0BRWVoCOCQ0iRIk=; b=RTNxwS9lyoOCfwlmmV9J/L5K1zl6DrsTA7+qYLOg5eP2FoaMC9BDHl2/1iAuqS98WaxF 1K37ly5FW5N7q6UmvaL491Y8vJNaJO9UGNuDg8OhNAieB9aV+nI90PqmlLiFyDAJElsBR 115YHlPfJpg2tcEMtHZC3VzqboxR9wr/gx0kGcovTd/XK2p6zHkd+NPV96cPSGbUfP5IZ yP7pe111LOKnjnBIMHikDMUxWgxE+ovVTYl9tc4M4j6ag5EKdakrSgHMnkxo1M7x7KR3G kypoxuHUYB/pJcw6YmKLI1xa9ArFXCj3HoWdLUZs4DLE1+6FNG6ayRiKBfIKmM1/WNg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=PRGVRqwi; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 41EB5606D834; Tue, 3 Nov 2026 13:56:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=PRGVRqwi Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA2751F00919; Tue, 3 Nov 2026 13:56:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793714196; bh=R+Lz59YAmE39OMTr2JsinbD50rhC0BRWVoCOCQ0iRIk=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=PRGVRqwiv6MTZLxMLY48nxHMWgsFAcHVQqSjW+03fKfFTsD8J7XY+8asguReA4+9l snQCwXIRcT2lHftHDW+j+YdpQHpcc5srRgKCGzH6x7BSYlcdDB49Kos+3hHbpdzNHk ASQNL0hGSSQY8OOqCvRS9PE4W/Hqayx/NDf8tVmYbRwktPhqDcX3R1fu7bbqxvp0xj 31mVkymrskroU2Jha52BCjuf0QoIlRgezvjuUqnDqHgkLwSsHxQpe7qjkntoITzsP/ MEwiv1hroVCqQKqyz0xcFcAdk1qJYylCzNHzOedSkkEI8WnvGjfAuAD3gXRsrICO/K YxYPo/kMew9lw== Date: Tue, 3 Nov 2026 13:56:31 +0000 From: Mark Brown To: Wei Wang Cc: Catalin Marinas , Will Deacon , Mark Rutland , "Rafael J . Wysocki" , linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, wei.vince.wang@gmail.com Subject: Re: [PATCH] arm64: suspend: Save and restore TPIDR2_EL0 across CPU suspend Message-ID: <8f1ccb65-e4a2-450b-944c-9883ff12bc37@sirena.org.uk> References: <20261102234813.1069156-1-wvw@google.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="6IYMj8soJ5dhvHDN" Content-Disposition: inline In-Reply-To: <20261102234813.1069156-1-wvw@google.com> X-Cookie: Small is beautiful. --6IYMj8soJ5dhvHDN Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Mon, Nov 02, 2026 at 11:48:13PM +0000, Wei Wang wrote: > On systems with FEAT_SME, TPIDR2_EL0 is part of userspace thread state: > the AAPCS64 SME ABI uses it as the ZA lazy-save pointer, and the kernel > context-switches it eagerly in tls_thread_switch(). While a task is > running, the live register is the only copy of its value. Thanks for catching this: Reviewed-by: Mark Brown but I think we're missing some other registers, I made the same mistake for GCS with GCSPR_EL0 and GCSCRE0_EL1 and I'm not seeing where POR_EL0 is handled either but possibly it's somewhere I didn't spot. I can look into those incrementally once this gets applied (or if you do a v2 and roll them in that'd also be great!). --6IYMj8soJ5dhvHDN Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmrp6A8ACgkQJNaLcl1U h9Djkwf8CKSaRV2sUPe1CvYTnDySz0g3vSKK7JXAzIRm7/VW/CeVsU7qAR2VxvOQ os/IemWfB91LhdGiI+0r7iVCLjU8tgnMmj6w5Yj+KZU15W7QeRxeYYC7orlzQbgK Uy/pLapQrvXwIu7ZxyE9BlPAvKyqTe3uHhJVZHyl8sGZ0vTs4+5osA94wsUG+ouk Ab9Qa8ycZf10jI8DUDVsWpZyXn704V81m+PfUziecTQp1FRQad8pDLcPcLk1oYf2 9Bk4ysiIbRYzVzi+5EFH2n6BTpKkw0nsUS6SZv2dxzX/dlmSb20Rd9kyId4WTWYS cmkbN8UklQLpeHEZFnpKhyVgOAtQcA== =zl37 -----END PGP SIGNATURE----- --6IYMj8soJ5dhvHDN--