From owner-svn-src-head@freebsd.org Sat Oct 27 21:04:35 2018 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id AE4C210D3543; Sat, 27 Oct 2018 21:04:35 +0000 (UTC) (envelope-from wulf@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 647A77AFAB; Sat, 27 Oct 2018 21:04:35 +0000 (UTC) (envelope-from wulf@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 26ECF15978; Sat, 27 Oct 2018 21:04:35 +0000 (UTC) (envelope-from wulf@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id w9RL4ZD1043922; Sat, 27 Oct 2018 21:04:35 GMT (envelope-from wulf@FreeBSD.org) Received: (from wulf@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id w9RL4YIM043919; Sat, 27 Oct 2018 21:04:34 GMT (envelope-from wulf@FreeBSD.org) Message-Id: <201810272104.w9RL4YIM043919@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: wulf set sender to wulf@FreeBSD.org using -f From: Vladimir Kondratyev Date: Sat, 27 Oct 2018 21:04:34 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r339824 - head/sys/dev/evdev X-SVN-Group: head X-SVN-Commit-Author: wulf X-SVN-Commit-Paths: head/sys/dev/evdev X-SVN-Commit-Revision: 339824 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 27 Oct 2018 21:04:36 -0000 Author: wulf Date: Sat Oct 27 21:04:34 2018 New Revision: 339824 URL: https://svnweb.freebsd.org/changeset/base/339824 Log: evdev: disable evdev if it is invoked from KDB or panic context This allow to prevent deadlock on entering KDB if one of evdev locks is already taken by userspace process. Also this change discards all but LED console events produced by KDB as unrelated to userspace. Tested by: dumbbell (as part of D15070) Objected by: bde (as 'KDB lock an already locked mutex' problem solution) MFC after: 1 month Modified: head/sys/dev/evdev/cdev.c head/sys/dev/evdev/evdev.c head/sys/dev/evdev/evdev_private.h Modified: head/sys/dev/evdev/cdev.c ============================================================================== --- head/sys/dev/evdev/cdev.c Sat Oct 27 20:22:41 2018 (r339823) +++ head/sys/dev/evdev/cdev.c Sat Oct 27 21:04:34 2018 (r339824) @@ -349,6 +349,19 @@ evdev_ioctl(struct cdev *dev, u_long cmd, caddr_t data if (client->ec_revoked || evdev == NULL) return (ENODEV); + /* + * Fix evdev state corrupted with discarding of kdb events. + * EVIOCGKEY and EVIOCGLED ioctls can suffer from this. + */ + if (evdev->ev_kdb_active) { + EVDEV_LOCK(evdev); + if (evdev->ev_kdb_active) { + evdev->ev_kdb_active = false; + evdev_restore_after_kdb(evdev); + } + EVDEV_UNLOCK(evdev); + } + /* file I/O ioctl handling */ switch (cmd) { case FIOSETOWN: Modified: head/sys/dev/evdev/evdev.c ============================================================================== --- head/sys/dev/evdev/evdev.c Sat Oct 27 20:22:41 2018 (r339823) +++ head/sys/dev/evdev/evdev.c Sat Oct 27 21:04:34 2018 (r339824) @@ -32,9 +32,11 @@ #include #include #include +#include #include #include #include +#include #include #include @@ -763,6 +765,30 @@ evdev_send_event(struct evdev_dev *evdev, uint16_t typ } } +void +evdev_restore_after_kdb(struct evdev_dev *evdev) +{ + int code; + + EVDEV_LOCK_ASSERT(evdev); + + /* Report postponed leds */ + for (code = 0; code < LED_CNT; code++) + if (bit_test(evdev->ev_kdb_led_states, code)) + evdev_send_event(evdev, EV_LED, code, + !bit_test(evdev->ev_led_states, code)); + bit_nclear(evdev->ev_kdb_led_states, 0, LED_MAX); + + /* Release stuck keys (CTRL + ALT + ESC) */ + evdev_stop_repeat(evdev); + for (code = 0; code < KEY_CNT; code++) { + if (bit_test(evdev->ev_key_states, code)) { + evdev_send_event(evdev, EV_KEY, code, KEY_EVENT_UP); + evdev_send_event(evdev, EV_SYN, SYN_REPORT, 1); + } + } +} + int evdev_push_event(struct evdev_dev *evdev, uint16_t type, uint16_t code, int32_t value) @@ -771,7 +797,25 @@ evdev_push_event(struct evdev_dev *evdev, uint16_t typ if (evdev_check_event(evdev, type, code, value) != 0) return (EINVAL); + /* + * Discard all but LEDs kdb events as unrelated to userspace. + * Aggregate LED updates and postpone reporting until kdb deactivation. + */ + if (kdb_active || SCHEDULER_STOPPED()) { + evdev->ev_kdb_active = true; + if (type == EV_LED) + bit_set(evdev->ev_kdb_led_states, + bit_test(evdev->ev_led_states, code) != value); + return (0); + } + EVDEV_ENTER(evdev); + + /* Fix evdev state corrupted with discarding of kdb events */ + if (evdev->ev_kdb_active) { + evdev->ev_kdb_active = false; + evdev_restore_after_kdb(evdev); + } evdev_modify_event(evdev, type, code, &value); if (type == EV_SYN && code == SYN_REPORT && Modified: head/sys/dev/evdev/evdev_private.h ============================================================================== --- head/sys/dev/evdev/evdev_private.h Sat Oct 27 20:22:41 2018 (r339823) +++ head/sys/dev/evdev/evdev_private.h Sat Oct 27 21:04:34 2018 (r339824) @@ -117,6 +117,10 @@ struct evdev_dev bitstr_t bit_decl(ev_sw_states, SW_CNT); bool ev_report_opened; + /* KDB state: */ + bool ev_kdb_active; + bitstr_t bit_decl(ev_kdb_led_states, LED_CNT); + /* Multitouch protocol type B state: */ struct evdev_mt * ev_mt; @@ -190,6 +194,7 @@ int evdev_cdev_destroy(struct evdev_dev *); bool evdev_event_supported(struct evdev_dev *, uint16_t); void evdev_set_abs_bit(struct evdev_dev *, uint16_t); void evdev_set_absinfo(struct evdev_dev *, uint16_t, struct input_absinfo *); +void evdev_restore_after_kdb(struct evdev_dev *); /* Client interface: */ int evdev_register_client(struct evdev_dev *, struct evdev_client *);