From owner-dev-commits-src-main@freebsd.org Sun Jan 10 22:08:52 2021 Return-Path: Delivered-To: dev-commits-src-main@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 7CA504DB96C; Sun, 10 Jan 2021 22:08:52 +0000 (UTC) (envelope-from git@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) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 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 4DDWFc35x5z3n99; Sun, 10 Jan 2021 22:08:52 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 5D1E87E81; Sun, 10 Jan 2021 22:08:52 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 10AM8q9u061866; Sun, 10 Jan 2021 22:08:52 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 10AM8qOx061865; Sun, 10 Jan 2021 22:08:52 GMT (envelope-from git) Date: Sun, 10 Jan 2021 22:08:52 GMT Message-Id: <202101102208.10AM8qOx061865@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Konstantin Belousov Subject: git: a013e285dfd6 - main - x86 tsc: mark %eax as earlyclobber in tscp_get_timecount_low(). MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: kib X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: a013e285dfd6b89b1908ca13febb0fdb0a7f3b1f Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-main@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for the main branch of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 10 Jan 2021 22:08:52 -0000 The branch main has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=a013e285dfd6b89b1908ca13febb0fdb0a7f3b1f commit a013e285dfd6b89b1908ca13febb0fdb0a7f3b1f Author: Konstantin Belousov AuthorDate: 2021-01-10 22:05:49 +0000 Commit: Konstantin Belousov CommitDate: 2021-01-10 22:05:49 +0000 x86 tsc: mark %eax as earlyclobber in tscp_get_timecount_low(). i386 codegen insists on preloading tc_priv into register on i386, and this register cannot be %eax because RDTSCP instruction clobbers it before it is used. Reported and tested by: dim MFC after: 6 days Sponsored by: The FreeBSD Foundation --- sys/x86/x86/tsc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sys/x86/x86/tsc.c b/sys/x86/x86/tsc.c index ad8108c8a7ea..85924df98312 100644 --- a/sys/x86/x86/tsc.c +++ b/sys/x86/x86/tsc.c @@ -826,7 +826,7 @@ tscp_get_timecount_low(struct timecounter *tc) uint32_t rv; __asm __volatile("rdtscp; movl %1, %%ecx; shrd %%cl, %%edx, %0" - : "=a" (rv) : "m" (tc->tc_priv) : "ecx", "edx"); + : "=&a" (rv) : "m" (tc->tc_priv) : "ecx", "edx"); return (rv); }