From nobody Wed Oct 06 02:54:33 2021 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 EC51712D7968; Wed, 6 Oct 2021 02:54:33 +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 4HPJvY4jFvz4gVq; Wed, 6 Oct 2021 02:54:33 +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 7099F188AB; Wed, 6 Oct 2021 02:54:33 +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 1962sXfh087661; Wed, 6 Oct 2021 02:54:33 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 1962sXka087660; Wed, 6 Oct 2021 02:54:33 GMT (envelope-from git) Date: Wed, 6 Oct 2021 02:54:33 GMT Message-Id: <202110060254.1962sXka087660@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: ce21d4bff1bc - main - amd64 efirt: do not flush cache for runtime pages 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: kib X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: ce21d4bff1bc7e562471eeab6fb012b35029bf50 Auto-Submitted: auto-generated X-ThisMailContainsUnwantedMimeParts: N The branch main has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=ce21d4bff1bc7e562471eeab6fb012b35029bf50 commit ce21d4bff1bc7e562471eeab6fb012b35029bf50 Author: Konstantin Belousov AuthorDate: 2021-10-05 14:14:11 +0000 Commit: Konstantin Belousov CommitDate: 2021-10-06 02:53:20 +0000 amd64 efirt: do not flush cache for runtime pages We actually do not know is it safe or not to flush cache for random BAR/register page existing in the system. It is well-known that for instance LAPICs cannot tolerate cache flush. As report indicates, there are more such devices. This issue typically affects AMD machines which do not report self-snoop, causing real CLFLUSH invocation on the mapped pages. Intels do self-snoop, so this change should be nop for them, and unsafe devices, if any, are already ignored. Reported and tested by: manu Reviewed by: alc, markj Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D32318 --- sys/amd64/amd64/efirt_machdep.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sys/amd64/amd64/efirt_machdep.c b/sys/amd64/amd64/efirt_machdep.c index 6fb64816385e..6fffd113f868 100644 --- a/sys/amd64/amd64/efirt_machdep.c +++ b/sys/amd64/amd64/efirt_machdep.c @@ -254,7 +254,7 @@ efi_create_1t1_map(struct efi_md *map, int ndesc, int descsz) vm_page_init_page(m, va, -1); m->order = VM_NFREEORDER + 1; /* invalid */ m->pool = VM_NFREEPOOL + 1; /* invalid */ - pmap_page_set_memattr(m, mode); + pmap_page_set_memattr_noflush(m, mode); } } VM_OBJECT_WUNLOCK(obj_1t1_pt);