Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751614AbaDUInh (ORCPT ); Mon, 21 Apr 2014 04:43:37 -0400 Received: from rtits2.realtek.com ([60.250.210.242]:41592 "EHLO rtits2.realtek.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751533AbaDUInf (ORCPT ); Mon, 21 Apr 2014 04:43:35 -0400 X-SpamFilter-By: BOX Solutions SpamTrap 5.39 with qID s3L8h31o014101, This message is accepted by code: ctloc85258 Message-ID: <5354DB0A.7060706@realsil.com.cn> Date: Mon, 21 Apr 2014 16:47:06 +0800 From: micky User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Borislav Petkov CC: lkml , Chris Ball , Wei WANG Subject: Re: rtsx_pci_sdmmc lockdep splat References: <20140415174934.GD4826@pd.tnic> <534DE1D7.3000308@realsil.com.cn> <20140420122055.GD19667@pd.tnic> In-Reply-To: <20140420122055.GD19667@pd.tnic> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [172.29.41.103] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Borislav Thank you for test the patch. It seems we can't use tasklet here due to mutex_lock. And the spinlock may removed, I'm prepare to resend a different patch later. Best Regards. micky On 04/20/2014 08:20 PM, Borislav Petkov wrote: > Hi, > > On Wed, Apr 16, 2014 at 09:50:15AM +0800, micky wrote: >> From: Micky Ching >> >> To avoid dead lock, we need make sure host->lock is always acquire >> before pcr->lock. But in irq handler, we acquired pcr->lock in rtsx mfd >> driver, and sd_isr_done_transfer() is called during pcr->lock already >> acquired. Since in sd_isr_done_transfer() the only work we do is schdule >> tasklet, the cmd_tasklet and data_tasklet never conflict, so it is safe >> to remove spin_lock() here. >> >> Signed-off-by: Micky Ching >> --- >> drivers/mmc/host/rtsx_pci_sdmmc.c | 4 +--- >> 1 file changed, 1 insertion(+), 3 deletions(-) >> >> diff --git a/drivers/mmc/host/rtsx_pci_sdmmc.c b/drivers/mmc/host/rtsx_pci_sdmmc.c >> index 453e1d4..40695e0 100644 >> --- a/drivers/mmc/host/rtsx_pci_sdmmc.c >> +++ b/drivers/mmc/host/rtsx_pci_sdmmc.c >> @@ -108,12 +108,10 @@ static void sd_isr_done_transfer(struct platform_device *pdev) >> { >> struct realtek_pci_sdmmc *host = platform_get_drvdata(pdev); >> - spin_lock(&host->lock); >> if (host->cmd) >> tasklet_schedule(&host->cmd_tasklet); >> - if (host->data) >> + else if (host->data) >> tasklet_schedule(&host->data_tasklet); >> - spin_unlock(&host->lock); >> } >> static void sd_request_timeout(unsigned long host_addr) >> -- > Patch wouldn't apply against rc1, so I had to add it by hand, diff > below. > > --- > diff --git a/drivers/mmc/host/rtsx_pci_sdmmc.c b/drivers/mmc/host/rtsx_pci_sdmmc.c > index 5fb994f9a653..d1d65c0d8d2e 100644 > --- a/drivers/mmc/host/rtsx_pci_sdmmc.c > +++ b/drivers/mmc/host/rtsx_pci_sdmmc.c > @@ -109,12 +109,10 @@ static void sd_isr_done_transfer(struct platform_device *pdev) > { > struct realtek_pci_sdmmc *host = platform_get_drvdata(pdev); > > - spin_lock(&host->lock); > if (host->cmd) > tasklet_schedule(&host->cmd_tasklet); > - if (host->data) > + else if (host->data) > tasklet_schedule(&host->data_tasklet); > - spin_unlock(&host->lock); > } > > static void sd_request_timeout(unsigned long host_addr) > -- > > Still needs more love: > > [ 95.112797] rtsx_pci_sdmmc rtsx_pci_sdmmc.0: sdmmc_get_cd: RTSX_BIPR = 0x00010000 > [ 95.115700] mmc0: mmc_rescan_try_freq: trying to init card at 400000 Hz > [ 95.118040] mmc0: clock 0Hz busmode 2 powermode 1 cs 0 Vdd 21 width 0 timing 0 > [ 95.122504] rtsx_pci_sdmmc rtsx_pci_sdmmc.0: sdmmc_switch_voltage: signal_voltage = 0 > [ 95.139469] mmc0: clock 400000Hz busmode 2 powermode 2 cs 0 Vdd 21 width 0 timing 0 > [ 95.155461] mmc0: starting CMD52 arg 00000c00 flags 00000195 > [ 95.158617] rtsx_pci_sdmmc rtsx_pci_sdmmc.0: sd_send_cmd: SD/MMC CMD 52, arg = 0x00000c00 > [ 95.255497] rtsx_pci_sdmmc rtsx_pci_sdmmc.0: timeout for request > [ 95.258412] ------------[ cut here ]------------ > [ 95.261163] WARNING: CPU: 0 PID: 3 at kernel/locking/mutex.c:698 __mutex_unlock_slowpath+0x124/0x180() > [ 95.264120] DEBUG_LOCKS_WARN_ON(in_interrupt()) > [ 95.264222] Modules linked in: cpufreq_stats cpufreq_conservative cpufreq_powersave cpufreq_userspace binfmt_misc uinput ipv6 vfat fat rtsx_pci_sdmmc mmc_core arc4 radeon rtl8192ce snd_hda_codec_conexant snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_intel rtl_pci rtlwifi snd_hda_controller snd_hda_codec mac80211 cfg80211 snd_hwdep snd_pcm drm_kms_helper pcspkr k10temp evdev snd_seq thermal thinkpad_acpi ehci_pci nvram rtsx_pci mfd_core snd_seq_device rtl8192c_common snd_timer ohci_pci ohci_hcd ehci_hcd snd battery ttm ac video button soundcore > [ 95.264231] CPU: 0 PID: 3 Comm: ksoftirqd/0 Not tainted 3.15.0-rc1+ #1 > [ 95.264235] Hardware name: LENOVO 30515QG/30515QG, BIOS 8RET30WW (1.12 ) 09/15/2011 > [ 95.264246] 0000000000000009 ffff8801198f3c50 ffffffff81522644 ffff8801198f3c98 > [ 95.264254] ffff8801198f3c88 ffffffff810701fc ffff8800c0ec1230 ffff8800c28b5c30 > [ 95.264262] ffff8800c0ec1000 ffff8800bea267b0 0000000000000000 ffff8801198f3ce8 > [ 95.264264] Call Trace: > [ 95.264277] [] dump_stack+0x4e/0x7a > [ 95.264288] [] warn_slowpath_common+0x8c/0xc0 > [ 95.264297] [] warn_slowpath_fmt+0x4c/0x50 > [ 95.264305] [] __mutex_unlock_slowpath+0x124/0x180 > [ 95.264311] [] mutex_unlock+0xe/0x10 > [ 95.264324] [] sd_finish_request+0xd9/0x1c0 [rtsx_pci_sdmmc] > [ 95.264332] [] tasklet_action+0x110/0x170 > [ 95.264338] [] __do_softirq+0x12a/0x320 > [ 95.264345] [] run_ksoftirqd+0x2d/0x50 > [ 95.264354] [] smpboot_thread_fn+0x175/0x2b0 > [ 95.264363] [] ? SyS_setgroups+0x150/0x150 > [ 95.264372] [] kthread+0xfc/0x120 > [ 95.264382] [] ? kthread_create_on_node+0x1f0/0x1f0 > [ 95.264390] [] ret_from_fork+0x7c/0xb0 > [ 95.264398] [] ? kthread_create_on_node+0x1f0/0x1f0 > [ 95.264403] ---[ end trace e7e46e1611dc934d ]--- > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/