From owner-dev-commits-src-all@freebsd.org Thu Mar 11 16:45:13 2021 Return-Path: Delivered-To: dev-commits-src-all@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 7531B57B871; Thu, 11 Mar 2021 16:45:13 +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 4DxFDT2q8Lz3Jqd; Thu, 11 Mar 2021 16:45:13 +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 4A68BFE; Thu, 11 Mar 2021 16:45:13 +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 12BGjDBU085232; Thu, 11 Mar 2021 16:45:13 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 12BGjDvh085231; Thu, 11 Mar 2021 16:45:13 GMT (envelope-from git) Date: Thu, 11 Mar 2021 16:45:13 GMT Message-Id: <202103111645.12BGjDvh085231@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Warner Losh Subject: git: 8423f5d4c127 - main - nvme: use config_intrhook_drain to avoid removable card races MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: imp X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 8423f5d4c127f18e7500bc455bc7b6b1691385ef Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-all@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for all branches of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 11 Mar 2021 16:45:13 -0000 The branch main has been updated by imp: URL: https://cgit.FreeBSD.org/src/commit/?id=8423f5d4c127f18e7500bc455bc7b6b1691385ef commit 8423f5d4c127f18e7500bc455bc7b6b1691385ef Author: Warner Losh AuthorDate: 2021-03-11 15:42:44 +0000 Commit: Warner Losh CommitDate: 2021-03-11 16:45:10 +0000 nvme: use config_intrhook_drain to avoid removable card races nvme drives are configured early in boot. However, a number of the configuration steps takes which take a while, so we defer those to a config intrhook that runs before the root filesystem is mounted. At the same time, the PCI hot plug wakes up and tests the status of the card. It may decide that the card has gone away and deletes the child. As part of that process nvme_detach is called. If this call happens after the config_intrhook starts to run, but before it is finished, there's a race where we can tear down the device's soft state while the config_intrhook is still using it. Use the new config_intrhook_drain to disestablish the hook. Either it will be removed w/o running, or the routine will wait for it to finish. This closes the race and allows safe hotplug at any time, even very early in boot. Sponsored by: Netflix, Inc Reviewed by: jhb, mav Differential Revision: https://reviews.freebsd.org/D29006 --- sys/dev/nvme/nvme.c | 5 +---- sys/dev/nvme/nvme_ctrlr.c | 2 -- 2 files changed, 1 insertion(+), 6 deletions(-) diff --git a/sys/dev/nvme/nvme.c b/sys/dev/nvme/nvme.c index 3c145c817f88..f36125ba247b 100644 --- a/sys/dev/nvme/nvme.c +++ b/sys/dev/nvme/nvme.c @@ -143,10 +143,7 @@ nvme_detach(device_t dev) { struct nvme_controller *ctrlr = DEVICE2SOFTC(dev); - if (ctrlr->config_hook.ich_arg != NULL) { - config_intrhook_disestablish(&ctrlr->config_hook); - ctrlr->config_hook.ich_arg = NULL; - } + config_intrhook_drain(&ctrlr->config_hook); nvme_ctrlr_destruct(ctrlr, dev); return (0); diff --git a/sys/dev/nvme/nvme_ctrlr.c b/sys/dev/nvme/nvme_ctrlr.c index 351c6839a6f6..9e45c0e2d19e 100644 --- a/sys/dev/nvme/nvme_ctrlr.c +++ b/sys/dev/nvme/nvme_ctrlr.c @@ -1135,7 +1135,6 @@ nvme_ctrlr_start_config_hook(void *arg) fail: nvme_ctrlr_fail(ctrlr); config_intrhook_disestablish(&ctrlr->config_hook); - ctrlr->config_hook.ich_arg = NULL; return; } @@ -1154,7 +1153,6 @@ fail: nvme_sysctl_initialize_ctrlr(ctrlr); config_intrhook_disestablish(&ctrlr->config_hook); - ctrlr->config_hook.ich_arg = NULL; ctrlr->is_initialized = 1; nvme_notify_new_controller(ctrlr);