From patchwork Fri Aug 28 15:27:39 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Grygorii Strashko X-Patchwork-Id: 7092291 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id AFEB5BEEC1 for ; Fri, 28 Aug 2015 15:30:33 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9615C2089E for ; Fri, 28 Aug 2015 15:30:32 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6E35C2083E for ; Fri, 28 Aug 2015 15:30:31 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZVLZj-000379-On; Fri, 28 Aug 2015 15:28:19 +0000 Received: from comal.ext.ti.com ([198.47.26.152]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZVLZg-00031k-PH for linux-arm-kernel@lists.infradead.org; Fri, 28 Aug 2015 15:28:17 +0000 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by comal.ext.ti.com (8.13.7/8.13.7) with ESMTP id t7SFRhZ8016719; Fri, 28 Aug 2015 10:27:43 -0500 Received: from DLEE70.ent.ti.com (dlemailx.itg.ti.com [157.170.170.113]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id t7SFRhB0011797; Fri, 28 Aug 2015 10:27:43 -0500 Received: from dlep32.itg.ti.com (157.170.170.100) by DLEE70.ent.ti.com (157.170.170.113) with Microsoft SMTP Server id 14.3.224.2; Fri, 28 Aug 2015 10:27:42 -0500 Received: from localhost (ileax41-snat.itg.ti.com [10.172.224.153]) by dlep32.itg.ti.com (8.14.3/8.13.8) with ESMTP id t7SFRfXE021302; Fri, 28 Aug 2015 10:27:42 -0500 From: Grygorii Strashko To: , Subject: [PATCH v2] ARM: OMAP2+: omap-device: fix race deferred probe of omap_hsmmc vs omap_device_late_init Date: Fri, 28 Aug 2015 18:27:39 +0300 Message-ID: <1440775659-21014-1-git-send-email-grygorii.strashko@ti.com> X-Mailer: git-send-email 2.5.0 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150828_082816_962588_7247C913 X-CRM114-Status: GOOD ( 16.99 ) X-Spam-Score: -8.3 (--------) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Grygorii Strashko , linux@arm.linux.org.uk, Keerthy , nsekhar@ti.com, balbi@ti.com, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-5.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Kernel fails to boot 50% of times (form build to build) with RT-patchset applied due to the following race - on late boot stages deferred_probe_work_func->omap_hsmmc_probe races with omap_device_late_ini. The same issue has been reported now on linux-next (4.3) by Keerthy [1] late_initcall - deferred_probe_initcal() tries to re-probe all pending driver's probe. - later on, some driver is probing in this case It's cpsw.c (but could be any other drivers) cpsw_init - platform_driver_register - really_probe - driver_bound - driver_deferred_probe_trigger and boot proceed. So, at this moment we have deferred_probe_work_func scheduled. late_initcall_sync - omap_device_late_init - omap_device_idle CPU1 CPU2 - deferred_probe_work_func - really_probe - omap_hsmmc_probe - pm_runtime_get_sync late_initcall_sync - omap_device_late_init if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER) { if (od->_state == OMAP_DEVICE_STATE_ENABLED) { - omap_device_idle [ops - IP is disabled] - [fail] - pm_runtime_put_sync - omap_hsmmc_runtime_suspend [ooops!] == log == omap_hsmmc 480b4000.mmc: unable to get vmmc regulator -517 davinci_mdio 48485000.mdio: davinci mdio revision 1.6 davinci_mdio 48485000.mdio: detected phy mask fffffff3 libphy: 48485000.mdio: probed davinci_mdio 48485000.mdio: phy[2]: device 48485000.mdio:02, driver unknown davinci_mdio 48485000.mdio: phy[3]: device 48485000.mdio:03, driver unknown omap_hsmmc 480b4000.mmc: unable to get vmmc regulator -517 cpsw 48484000.ethernet: Detected MACID = b4:99:4c:c7:d2:48 cpsw 48484000.ethernet: cpsw: Detected MACID = b4:99:4c:c7:d2:49 hctosys: unable to open rtc device (rtc0) omap_hsmmc 480b4000.mmc: omap_device_late_idle: enabled but no driver. Idling ldousb: disabling Unhandled fault: imprecise external abort (0x1406) at 0x00000000 [00000000] *pgd=00000000 Internal error: : 1406 [#1] PREEMPT SMP ARM Modules linked in: CPU: 1 PID: 58 Comm: kworker/u4:1 Not tainted 4.1.2-rt1-00467-g6da3c0a-dirty #5 Hardware name: Generic DRA74X (Flattened Device Tree) Workqueue: deferwq deferred_probe_work_func task: ee6ddb00 ti: edd3c000 task.ti: edd3c000 PC is at omap_hsmmc_runtime_suspend+0x1c/0x12c LR is at _od_runtime_suspend+0xc/0x24 pc : [] lr : [] psr: a0000013 sp : edd3dda0 ip : ee6ddb00 fp : c07be540 r10: 00000000 r9 : c07be540 r8 : 00000008 r7 : 00000000 r6 : ee646c10 r5 : ee646c10 r4 : edd79380 r3 : fa0b4100 r2 : 00000000 r1 : 00000000 r0 : ee646c10 Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel Control: 10c5387d Table: 8000406a DAC: 00000015 Process kworker/u4:1 (pid: 58, stack limit = 0xedd3c218) Stack: (0xedd3dda0 to 0xedd3e000) dda0: ee646c70 ee646c10 c0029584 00000000 00000008 c0029590 ee646c70 ee646c10 ddc0: c0029584 c03adfb8 ee646c10 00000004 0000000c c03adff0 ee646c10 00000004 dde0: 0000000c c03ae4ec 00000000 edd3c000 ee646c10 00000004 ee646c70 00000004 de00: fa0b4000 c03aec20 ee6ddb00 ee646c10 00000004 ee646c70 ee646c10 fffffdfb de20: edd79380 00000000 fa0b4000 c03aee90 fffffdfb edd79000 ee646c00 c0474290 de40: 00000000 edda24c0 edd79380 edc81f00 00000000 00000200 00000001 c06dd488 de60: edda3960 ee646c10 ee646c10 c0824cc4 fffffdfb c0880c94 00000002 edc92600 de80: c0836378 c03a7f84 ee646c10 c0824cc4 00000000 c0880c80 c0880c94 c03a6568 dea0: 00000000 ee646c10 c03a66ac ee4f8000 00000000 00000001 edc92600 c03a4b40 dec0: ee404c94 edc83c4c ee646c10 ee646c10 ee646c44 c03a63c4 ee646c10 ee646c10 dee0: c0814448 c03a5aa8 ee646c10 c0814220 edd3c000 c03a5ec0 c0814250 ee6be400 df00: edd3c000 c004e5bc ee6ddb01 00000078 ee6ddb00 ee4f8000 ee6be418 edd3c000 df20: ee4f8028 00000088 c0836045 ee4f8000 ee6be400 c004e928 ee4f8028 00000000 df40: c004e8ec 00000000 ee6bf1c0 ee6be400 c004e8ec 00000000 00000000 00000000 df60: 00000000 c0053450 2e56fa97 00000000 afdffbd7 ee6be400 00000000 00000000 df80: edd3df80 edd3df80 00000000 00000000 edd3df90 edd3df90 edd3dfac ee6bf1c0 dfa0: c0053384 00000000 00000000 c000f668 00000000 00000000 00000000 00000000 dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 f1fc9d7e febfbdff [] (omap_hsmmc_runtime_suspend) from [] (_od_runtime_suspend+0xc/0x24) [] (_od_runtime_suspend) from [] (__rpm_callback+0x24/0x3c) [] (__rpm_callback) from [] (rpm_callback+0x20/0x80) [] (rpm_callback) from [] (rpm_suspend+0xe4/0x618) [] (rpm_suspend) from [] (__pm_runtime_idle+0x60/0x80) [] (__pm_runtime_idle) from [] (omap_hsmmc_probe+0x6bc/0xa7c) [] (omap_hsmmc_probe) from [] (platform_drv_probe+0x44/0xa4) [] (platform_drv_probe) from [] (driver_probe_device+0x170/0x2b4) [] (driver_probe_device) from [] (bus_for_each_drv+0x64/0x98) [] (bus_for_each_drv) from [] (device_attach+0x70/0x88) [] (device_attach) from [] (bus_probe_device+0x84/0xac) [] (bus_probe_device) from [] (deferred_probe_work_func+0x58/0x88) [] (deferred_probe_work_func) from [] (process_one_work+0x134/0x464) [] (process_one_work) from [] (worker_thread+0x3c/0x4fc) [] (worker_thread) from [] (kthread+0xcc/0xe4) [] (kthread) from [] (ret_from_fork+0x14/0x2c) Code: e594302c e593202c e584205c e594302c (e5932128) ---[ end trace 0000000000000002 ]--- The issue happens because omap_device_late_init() do not take into account that some drivers are present, but their probes were not finished successfully and where deferred instead. This is the valid case, and omap_device_late_init() should not idle such devices. To fix this issue, the value of omap_device->_driver_status field should be checked not only for BUS_NOTIFY_BOUND_DRIVER (driver is present and has been bound to device successfully), but also checked for BUS_NOTIFY_BIND_DRIVER (driver about to be bound) - which means driver is present and there was try to bind it to device. [1] http://www.spinics.net/lists/arm-kernel/msg441880.html Cc: Tero Kristo Cc: Keerthy Tested-by: Keerthy Signed-off-by: Grygorii Strashko --- Changes in v2: - implementation changed: added additional check for BUS_NOTIFY_BIND_DRIVER instead of removing omap_device_late_init. Link on v1: http://www.spinics.net/lists/arm-kernel/msg441594.html arch/arm/mach-omap2/omap_device.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm/mach-omap2/omap_device.c b/arch/arm/mach-omap2/omap_device.c index 4cb8fd9..72ebc4c 100644 --- a/arch/arm/mach-omap2/omap_device.c +++ b/arch/arm/mach-omap2/omap_device.c @@ -901,7 +901,8 @@ static int __init omap_device_late_idle(struct device *dev, void *data) if (od->hwmods[i]->flags & HWMOD_INIT_NO_IDLE) return 0; - if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER) { + if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER && + od->_driver_status != BUS_NOTIFY_BIND_DRIVER) { if (od->_state == OMAP_DEVICE_STATE_ENABLED) { dev_warn(dev, "%s: enabled but no driver. Idling\n", __func__);