From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Hutchings Subject: Is e_powersaver safe to auto-load? Date: Sat, 11 Feb 2012 23:33:10 +0000 Message-ID: <1329003190.325.78.camel@deadeye> Mime-Version: 1.0 Content-Type: multipart/signed; micalg="pgp-sha512"; protocol="application/pgp-signature"; boundary="=-a7UKWTMNGxxGlO1S3DEP" Return-path: Sender: cpufreq-owner@vger.kernel.org List-ID: To: Dave Jones , =?UTF-8?Q?Rafa=C5=82?= Bilski Cc: cpufreq@vger.kernel.org, Andi Kleen --=-a7UKWTMNGxxGlO1S3DEP Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable The e_powersaver driver comes with a dire warning in Kconfig help: VIA C7 Enhanced PowerSaver (DANGEROUS) This adds the CPUFreq driver for VIA C7 processors. However, this driv= er does not have any safeguards to prevent operating the CPU out of spec and is thus considered dangerous. Please use the regular ACPI cpufreq driver, enabled by CONFIG_X86_ACPI_CPUFREQ. Following the bug report , Debian's cpufrequtils init script was changed to stop loading it. The driver was later disabled in Debian kernel configurations. Rafa=C5=82 appears to have made it somewhat safer since then, but the help text has not been changed. Since commit fa8031aefec0cf7ea6c2387c93610d99d9659aa2 ('cpufreq: Add support for x86 cpuinfo auto loading v4') the driver will be auto-loaded on some systems. If it is still dangerous then it should surely not be auto-loaded. But if it is now believed to be safe then the help text should be updated to say so. Ben. --=20 Ben Hutchings The two most common things in the universe are hydrogen and stupidity. --=-a7UKWTMNGxxGlO1S3DEP Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIVAwUATzb6tue/yOyVhhEJAQoXqQ//Z9ND/9+ZJ9VB/DqJPyYUJkovnu3M1ZW/ qETECYUAXKyPGtsAw7WevZGb+KjvwlRPlt18rPnj7b/dv5G7aLDbR8yQBgsnisAL Wud7MQcZXlCPD+Y6GOmRM0nl3wFzi+FYk6bCkHqmVhMOZP/OKa7GrJ3HVj2Tju02 AYxIspX+YnBjDypcDFeXlW2af54ZdYkDW5BSHPaXA6wwk3qqhkvHU6LvS4hfkKq1 Kya6yBB3h1Gaa17oatZpimxiFGgxoxLIh/lNMrxFouMhS/nyqXzQPrHD8hx6aNZ/ O8BR8xu189kgiQqBvrvHKMymrrjn66oX8dscB1ruXySbzKBLlWOOwVtMbnul3YGC f8CKEPalvviWWrCB+VqzT2+T1y29ZtDIn0TZYVW0onN//SJnSZu//+A7uzwIv4UM sVFeqoWWRzCtli4J42uJ2k0+cMMNGhUFf5J/+395cG8OMm/pKYNoRbcHMMLq4Wkv KFGVWVmgRpVslLfsE7PhJ8j+09+CMCrwJY6kcpaqCD7xuqslrp0UJGBAh947ube2 GeMDxqNceuqX15nf/anwqbK9Z1UGqk3H15Di0h6ZezVOuzVSPc3IJHVTwajnBEAC 6rZ8CMPViTz+6aYwmpYXllv0M+RF6yOzBbwTX6BIFGcFGKZWL4Unvi3bcOeSHNUN uYaSaNBVX7A= =4rtR -----END PGP SIGNATURE----- --=-a7UKWTMNGxxGlO1S3DEP--