From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 70203385841B; Tue, 29 Aug 2023 19:58:02 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 70203385841B DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1693339082; bh=5FyzaHxSL465QAh4+PjcfKzEL0xAsRJOP86p8pJfoek=; h=From:To:Subject:Date:In-Reply-To:References:From; b=U5r4cPl2wDHiOQh3145LZg19A71hBpTrMJZZRvl9eVF1nkfruSq2A2Z4OZBHq32qm CtL8WVqPdR4ck3T8pO1yf8GS66PjzW86xe3wY0pYk1efZMyPB+ym0aeqBf2jWT43dw A7Osjx1Sl4qhbrF3/V/WhVuAokfloTuDTzu7ehEM= From: "cvs-commit at gcc dot gnu.org" To: glibc-bugs@sourceware.org Subject: [Bug libc/30643] Missing cache information on x86-64 under Intel TDX Date: Tue, 29 Aug 2023 19:58:01 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: glibc X-Bugzilla-Component: libc X-Bugzilla-Version: unspecified X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: cvs-commit at gcc dot gnu.org X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: hjl.tools at gmail dot com X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: security- 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: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://sourceware.org/bugzilla/show_bug.cgi?id=3D30643 --- Comment #12 from cvs-commit at gcc dot gnu.org --- The master branch has been updated by H.J. Lu : https://sourceware.org/git/gitweb.cgi?p=3Dglibc.git;h=3D1493622f4f9048ffede= 3fbedb64695efa49d662a commit 1493622f4f9048ffede3fbedb64695efa49d662a Author: H.J. Lu Date: Mon Aug 28 12:08:14 2023 -0700 x86: Check the lower byte of EAX of CPUID leaf 2 [BZ #30643] The old Intel software developer manual specified that the low byte of EAX of CPUID leaf 2 returned 1 which indicated the number of rounds of CPUDID leaf 2 was needed to retrieve the complete cache information. The newer Intel manual has been changed to that it should always return 1 and be ignored. If the lower byte isn't 1, CPUID leaf 2 can't be used. In this case, we ignore CPUID leaf 2 and use CPUID leaf 4 instead. If CPUID leaf 4 doesn't contain the cache information, cache information isn't available at all. This addresses BZ #30643. --=20 You are receiving this mail because: You are on the CC list for the bug.=