From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vivek Gautam Subject: Re: [PATCH RESEND] iommu/msm: Don't call iommu_device_{, un}link from atomic context Date: Thu, 14 Jun 2018 12:37:11 +0530 Message-ID: References: <20180612140610.31190-1-niklas.cassel@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180612140610.31190-1-niklas.cassel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Niklas Cassel Cc: linux-arm-msm , "list-Y9sIeH5OGRo@public.gmane.org:IOMMU DRIVERS , Joerg Roedel , " , open list List-Id: iommu@lists.linux-foundation.org Hi NIklas, On Tue, Jun 12, 2018 at 7:36 PM, Niklas Cassel wrote: > Fixes the following splat during boot: > > BUG: sleeping function called from invalid context at kernel/locking/mutex.c:747 > in_atomic(): 1, irqs_disabled(): 128, pid: 77, name: kworker/2:1 > 4 locks held by kworker/2:1/77: > #0: (ptrval) ((wq_completion)"events"){+.+.}, at: process_one_work+0x1fc/0x8fc > #1: (ptrval) (deferred_probe_work){+.+.}, at: process_one_work+0x1fc/0x8fc > #2: (ptrval) (&dev->mutex){....}, at: __device_attach+0x40/0x178 > #3: (ptrval) (msm_iommu_lock){....}, at: msm_iommu_add_device+0x28/0xcc > irq event stamp: 348 > hardirqs last enabled at (347): [] kfree+0xe0/0x3c0 > hardirqs last disabled at (348): [] _raw_spin_lock_irqsave+0x2c/0x68 > softirqs last enabled at (0): [] copy_process.part.5+0x280/0x1a68 > softirqs last disabled at (0): [<00000000>] (null) > Preemption disabled at: > [<00000000>] (null) > CPU: 2 PID: 77 Comm: kworker/2:1 Not tainted 4.17.0-rc5-wt-ath-01075-gaca0516bb4cf #239 > Hardware name: Generic DT based system > Workqueue: events deferred_probe_work_func > [] (unwind_backtrace) from [] (show_stack+0x20/0x24) > [] (show_stack) from [] (dump_stack+0xa0/0xcc) > [] (dump_stack) from [] (___might_sleep+0x1f8/0x2d4) > ath10k_sdio mmc2:0001:1: Direct firmware load for ath10k/QCA9377/hw1.0/board-2.bin failed with error -2 > [] (___might_sleep) from [] (__might_sleep+0x70/0xa8) > [] (__might_sleep) from [] (__mutex_lock+0x50/0xb28) > [] (__mutex_lock) from [] (mutex_lock_nested+0x2c/0x34) > ath10k_sdio mmc2:0001:1: board_file api 1 bmi_id N/A crc32 544289f7 > [] (mutex_lock_nested) from [] (kernfs_find_and_get_ns+0x30/0x5c) > [] (kernfs_find_and_get_ns) from [] (sysfs_add_link_to_group+0x28/0x58) > [] (sysfs_add_link_to_group) from [] (iommu_device_link+0x50/0xb4) > [] (iommu_device_link) from [] (msm_iommu_add_device+0xa0/0xcc) > [] (msm_iommu_add_device) from [] (add_iommu_group+0x3c/0x64) > [] (add_iommu_group) from [] (bus_for_each_dev+0x84/0xc4) > [] (bus_for_each_dev) from [] (bus_set_iommu+0xd0/0x10c) > [] (bus_set_iommu) from [] (msm_iommu_probe+0x5b8/0x66c) > [] (msm_iommu_probe) from [] (platform_drv_probe+0x60/0xbc) > [] (platform_drv_probe) from [] (driver_probe_device+0x30c/0x4cc) > [] (driver_probe_device) from [] (__device_attach_driver+0xac/0x14c) > [] (__device_attach_driver) from [] (bus_for_each_drv+0x68/0xc8) > [] (bus_for_each_drv) from [] (__device_attach+0xe4/0x178) > [] (__device_attach) from [] (device_initial_probe+0x1c/0x20) > [] (device_initial_probe) from [] (bus_probe_device+0x98/0xa0) > [] (bus_probe_device) from [] (deferred_probe_work_func+0x74/0x198) > [] (deferred_probe_work_func) from [] (process_one_work+0x2c4/0x8fc) > [] (process_one_work) from [] (worker_thread+0x2c4/0x5cc) > [] (worker_thread) from [] (kthread+0x180/0x188) > [] (kthread) from [] (ret_from_fork+0x14/0x20) > > Fixes: 42df43b36163 ("iommu/msm: Make use of iommu_device_register interface") > Signed-off-by: Niklas Cassel > --- Thanks for the patch. Reviewed-by: Vivek Gautam Best regards Vivek > drivers/iommu/msm_iommu.c | 16 +++++----------- > 1 file changed, 5 insertions(+), 11 deletions(-) > > diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c > index 0d3350463a3f..9a95c9b9d0d8 100644 > --- a/drivers/iommu/msm_iommu.c > +++ b/drivers/iommu/msm_iommu.c > @@ -395,20 +395,15 @@ static int msm_iommu_add_device(struct device *dev) > struct msm_iommu_dev *iommu; > struct iommu_group *group; > unsigned long flags; > - int ret = 0; > > spin_lock_irqsave(&msm_iommu_lock, flags); > - > iommu = find_iommu_for_dev(dev); > + spin_unlock_irqrestore(&msm_iommu_lock, flags); > + > if (iommu) > iommu_device_link(&iommu->iommu, dev); > else > - ret = -ENODEV; > - > - spin_unlock_irqrestore(&msm_iommu_lock, flags); > - > - if (ret) > - return ret; > + return -ENODEV; > > group = iommu_group_get_for_dev(dev); > if (IS_ERR(group)) > @@ -425,13 +420,12 @@ static void msm_iommu_remove_device(struct device *dev) > unsigned long flags; > > spin_lock_irqsave(&msm_iommu_lock, flags); > - > iommu = find_iommu_for_dev(dev); > + spin_unlock_irqrestore(&msm_iommu_lock, flags); > + > if (iommu) > iommu_device_unlink(&iommu->iommu, dev); > > - spin_unlock_irqrestore(&msm_iommu_lock, flags); > - > iommu_group_remove_device(dev); > } > > -- > 2.17.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation