From nobody Sun May 28 14:07:48 2023 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4QTgTx116wz4XQvy; Sun, 28 May 2023 14:07:49 +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 "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4QTgTw5M1nz4Fb5; Sun, 28 May 2023 14:07:48 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1685282868; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=0/jVeRT6gRnk3uyBCrviPh7Klmkkphy/n7X8u0ar3Lw=; b=yvSfbizj2nWd4LFKC0eaEhWAgwlV7QbPAwPBHy5+6WEV76wxPO764VXR1+WUlQI3HwOfoK vz1yzWngQagO5SeIX3/klhtcUk65zxYjIUdcnlHM2IBwb3yCQ/pONtxvciZNwkz/FxzBZI 2irVe9Ks18zvSY/HdTd+W0UdtNB6J154n8UpWsLSfktujNKwKu60c2F4o2Pi3epIhrbPgJ KMz6PC/JqPsWfDhcGz5q+xkZ1ojFvjUpcGG4WBWKqMzI5ofBMq4LSFfO4UNqWo4xTPNXFb Y2uWOxQRMl8Lhul4cB6Ns1UyqnsT7OTtr6JitvttuLGWSDGpsPD2X4oCoECn5Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1685282868; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=0/jVeRT6gRnk3uyBCrviPh7Klmkkphy/n7X8u0ar3Lw=; b=EkQxARWgjzmRCSzXjmWqzAk4S7WEwQnSwzKyZ/bPkbQM0sGLBLAn9b8y/ezdC6cFlVaEKi Kh8Mzo2Pn55lIG6vkyoSlnpj4qcY88puCjAUExIgzi7A6VPemDki/wSO962o87lhdlC/6Y ilTlB68VcO+SY9KcsmX6gv3MUFW568Zn28PaAXec4TMI8uYoefV+L2YkInbrA9m8YNuHP5 MO2yksZTNAMlyKPG3JH8ijApsnRr+fEV5qQ0u+gu/oLBKRIO/IyeErCXuVZTVwREK7xOpz NtcqQXjSHkmLBRLjyTUPhWBfAOdrv5ddUjIgkt5C8VlmZI8BIQfJ3Nj7iwwRdg== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1685282868; a=rsa-sha256; cv=none; b=lA03g7ajZ1V6tYCJf2yv+Qxxw4i8M8iMgoNPMYIkGBJBivyNIDDZiwMjH7LM0VCSJh5pNM DfdNHCYqqhbdBRBZ+8LsIL5VCd5PLQHwplj1pvb46T4b6I2wTfWOKt+oDi/poDTw3mvhZr jmfOKk2Aomdcqj/LOL73ExJq8zWV1vLGdZdx93rG3DjYoOpQnaI8vPTMkV5Lyh555FDEED T7e9Ti66//IBsp4volc94pfW9YcRyRCF7SHUQqjI08s2Sqr6Fd0R3SP56vDOIQs3RVIeze k81pzJWBdLqMzxms3v0Gxa79yQvF2jdS/xG4dmytHLtZq9I0gOuErOWQJAGASA== 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 4QTgTw4SRdzXx2; Sun, 28 May 2023 14:07:48 +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 34SE7m0N067239; Sun, 28 May 2023 14:07:48 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 34SE7mSc067238; Sun, 28 May 2023 14:07:48 GMT (envelope-from git) Date: Sun, 28 May 2023 14:07:48 GMT Message-Id: <202305281407.34SE7mSc067238@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Dmitry Chagin Subject: git: 037b60fb0fbc - main - linux(4): Preserve %rcx (return address) like a Linux do List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-all@freebsd.org X-BeenThere: dev-commits-src-all@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: dchagin X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 037b60fb0fbcb2dd6b6cbb632b05a2939ff4ff29 Auto-Submitted: auto-generated X-ThisMailContainsUnwantedMimeParts: N The branch main has been updated by dchagin: URL: https://cgit.FreeBSD.org/src/commit/?id=037b60fb0fbcb2dd6b6cbb632b05a2939ff4ff29 commit 037b60fb0fbcb2dd6b6cbb632b05a2939ff4ff29 Author: Dmitry Chagin AuthorDate: 2023-05-28 14:06:47 +0000 Commit: Dmitry Chagin CommitDate: 2023-05-28 14:06:47 +0000 linux(4): Preserve %rcx (return address) like a Linux do Perhaps, this does not makes much sense as destroyng %rcx declared by the x86_64 Linux syscall ABI. However,: a) if we get a signal while we are in the kernel, we should restore tf_rcx when preparing machine context for signal handlers. b) the Linux world is strange, someone can depend on %rcx value after syscall, something like go. Differential Revision: https://reviews.freebsd.org/D40155 MFC after: 1 month --- sys/amd64/linux/linux_sysvec.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/sys/amd64/linux/linux_sysvec.c b/sys/amd64/linux/linux_sysvec.c index 422cfbe7c5ba..05afcdfcd045 100644 --- a/sys/amd64/linux/linux_sysvec.c +++ b/sys/amd64/linux/linux_sysvec.c @@ -169,6 +169,8 @@ linux_fetch_syscall_args(struct thread *td) /* Restore r10 earlier to avoid doing this multiply times. */ frame->tf_r10 = frame->tf_rcx; + /* Restore %rcx for machine context. */ + frame->tf_rcx = frame->tf_rip; td->td_retval[0] = 0; return (0);