From owner-freebsd-bugs@freebsd.org Mon Jan 27 04:52:00 2020 Return-Path: Delivered-To: freebsd-bugs@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id D63BB23067F for ; Mon, 27 Jan 2020 04:52:00 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mailman.nyi.freebsd.org (unknown [127.0.1.3]) by mx1.freebsd.org (Postfix) with ESMTP id 485cmJ5Ltlz3Pmp for ; Mon, 27 Jan 2020 04:52:00 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.nyi.freebsd.org (Postfix) id B30C623067B; Mon, 27 Jan 2020 04:52:00 +0000 (UTC) Delivered-To: bugs@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id B2CCA23067A for ; Mon, 27 Jan 2020 04:52:00 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 485cmJ4LrFz3Pml for ; Mon, 27 Jan 2020 04:52:00 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 90DD34B4B for ; Mon, 27 Jan 2020 04:52:00 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 00R4q0tM041139 for ; Mon, 27 Jan 2020 04:52:00 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 00R4q0di041114 for bugs@FreeBSD.org; Mon, 27 Jan 2020 04:52:00 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 234733] Setting CPU frequency with sysctl dev.cpu.0.fr slows a Ryzen 2700X down Date: Mon, 27 Jan 2020 04:52:00 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 12.0-STABLE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: cem@freebsd.org X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: bugs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 27 Jan 2020 04:52:00 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D234733 --- Comment #11 from Conrad Meyer --- Very interesting, thanks! It's the low bits of 0xc0010061 following 0xc001= 0062 up that is surprising / causing hwpstate(4) to ignore the user's supplied configuration (side note: we should really produce at least a *debug* log message when we ignore the user-supplied P-state!). I don't have an explanation for why 0xc0010061 low bits are following 0xc0010062. Nothing = in the kernel writes that MSR, as far as I can tell. The documentation I have for c0010061 says it's error-on-write. But it also suggests that the value may be changed: "Attempts to change the CurPstateLi= mit to a value greater (lower performance) than PStateCurLim[PstateMaxVal] leav= es CurPstateLimit unchanged.") So I'm not really sure if software/firmware can write it. Maybe the CPU's power-governor is misconfigured and is attemptin= g to limit itself? I don't have any explanation for why it would "follow" c0010= 062 stepwise, though. Any chance other people with the same motherboard have reported similar problems with Linux/Windows? Any chance there is a BIOS update available? --=20 You are receiving this mail because: You are the assignee for the bug.=