Messages in this thread | | | From | John Garry <> | Subject | Re: [PATCH] driver core: Postpone DMA tear-down until after devres release for probe failure | Date | Wed, 3 Apr 2019 09:02:36 +0100 |
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On 28/03/2019 10:08, John Garry wrote: > In commit 376991db4b64 ("driver core: Postpone DMA tear-down until after > devres release"), we changed the ordering of tearing down the device DMA > ops and releasing all the device's resources; this was because the DMA ops > should be maintained until we release the device's managed DMA memories. >
Hi all,
A friendly reminder on this patch... I didn't see any update.
I thought that it had some importance.
Thanks, John
> However, we have seen another crash on an arm64 system when a > device driver probe fails: > > hisi_sas_v3_hw 0000:74:02.0: Adding to iommu group 2 > scsi host1: hisi_sas_v3_hw > BUG: Bad page state in process swapper/0 pfn:313f5 > page:ffff7e0000c4fd40 count:1 mapcount:0 > mapping:0000000000000000 index:0x0 > flags: 0xfffe00000001000(reserved) > raw: 0fffe00000001000 ffff7e0000c4fd48 ffff7e0000c4fd48 > 0000000000000000 > raw: 0000000000000000 0000000000000000 00000001ffffffff > 0000000000000000 > page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set > bad because of flags: 0x1000(reserved) > Modules linked in: > CPU: 49 PID: 1 Comm: swapper/0 Not tainted > 5.1.0-rc1-43081-g22d97fd-dirty #1433 > Hardware name: Huawei D06/D06, BIOS Hisilicon D06 UEFI > RC0 - V1.12.01 01/29/2019 > Call trace: > dump_backtrace+0x0/0x118 > show_stack+0x14/0x1c > dump_stack+0xa4/0xc8 > bad_page+0xe4/0x13c > free_pages_check_bad+0x4c/0xc0 > __free_pages_ok+0x30c/0x340 > __free_pages+0x30/0x44 > __dma_direct_free_pages+0x30/0x38 > dma_direct_free+0x24/0x38 > dma_free_attrs+0x9c/0xd8 > dmam_release+0x20/0x28 > release_nodes+0x17c/0x220 > devres_release_all+0x34/0x54 > really_probe+0xc4/0x2c8 > driver_probe_device+0x58/0xfc > device_driver_attach+0x68/0x70 > __driver_attach+0x94/0xdc > bus_for_each_dev+0x5c/0xb4 > driver_attach+0x20/0x28 > bus_add_driver+0x14c/0x200 > driver_register+0x6c/0x124 > __pci_register_driver+0x48/0x50 > sas_v3_pci_driver_init+0x20/0x28 > do_one_initcall+0x40/0x25c > kernel_init_freeable+0x2b8/0x3c0 > kernel_init+0x10/0x100 > ret_from_fork+0x10/0x18 > Disabling lock debugging due to kernel taint > BUG: Bad page state in process swapper/0 pfn:313f6 > page:ffff7e0000c4fd80 count:1 mapcount:0 > mapping:0000000000000000 index:0x0 > [ 89.322983] flags: 0xfffe00000001000(reserved) > raw: 0fffe00000001000 ffff7e0000c4fd88 ffff7e0000c4fd88 > 0000000000000000 > raw: 0000000000000000 0000000000000000 00000001ffffffff > 0000000000000000 > > The crash occurs for the same reason. > > In this case, on the really_probe() failure path, we are still clearing > the DMA ops prior to releasing the device's managed memories. > > This patch fixes this issue by reordering the DMA ops teardown and the > call to devres_release_all() on the failure path. > > Reported-by: Xiang Chen <chenxiang66@hisilicon.com> > Tested-by: Xiang Chen <chenxiang66@hisilicon.com> > Signed-off-by: John Garry <john.garry@huawei.com> > --- > > For convenience, here is the 2nd half of really_probe() now: > > atomic_inc(&probe_count); > pr_debug("bus: '%s': %s: probing driver %s with device %s\n", > drv->bus->name, __func__, drv->name, dev_name(dev)); > WARN_ON(!list_empty(&dev->devres_head)); > > re_probe: > dev->driver = drv; > > /* If using pinctrl, bind pins now before probing */ > ret = pinctrl_bind_pins(dev); > if (ret) > goto pinctrl_bind_failed; > > if (dev->bus->dma_configure) { > ret = dev->bus->dma_configure(dev); > if (ret) > goto probe_failed; > } > > if (driver_sysfs_add(dev)) { > printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n", > __func__, dev_name(dev)); > goto probe_failed; > } > > if (dev->pm_domain && dev->pm_domain->activate) { > ret = dev->pm_domain->activate(dev); > if (ret) > goto probe_failed; > } > > if (dev->bus->probe) { > ret = dev->bus->probe(dev); > if (ret) > goto probe_failed; > } else if (drv->probe) { > ret = drv->probe(dev); > if (ret) > goto probe_failed; > } > > if (test_remove) { > test_remove = false; > > if (dev->bus->remove) > dev->bus->remove(dev); > else if (drv->remove) > drv->remove(dev); > > devres_release_all(dev); > driver_sysfs_remove(dev); > dev->driver = NULL; > dev_set_drvdata(dev, NULL); > if (dev->pm_domain && dev->pm_domain->dismiss) > dev->pm_domain->dismiss(dev); > pm_runtime_reinit(dev); > > goto re_probe; > } > > pinctrl_init_done(dev); > > if (dev->pm_domain && dev->pm_domain->sync) > dev->pm_domain->sync(dev); > > driver_bound(dev); > ret = 1; > pr_debug("bus: '%s': %s: bound device %s to driver %s\n", > drv->bus->name, __func__, dev_name(dev), drv->name); > goto done; > > probe_failed: > if (dev->bus) > blocking_notifier_call_chain(&dev->bus->p->bus_notifier, > BUS_NOTIFY_DRIVER_NOT_BOUND, dev); > pinctrl_bind_failed: > device_links_no_driver(dev); > devres_release_all(dev); > arch_teardown_dma_ops(dev); > driver_sysfs_remove(dev); > dev->driver = NULL; > dev_set_drvdata(dev, NULL); > if (dev->pm_domain && dev->pm_domain->dismiss) > dev->pm_domain->dismiss(dev); > pm_runtime_reinit(dev); > dev_pm_set_driver_flags(dev, 0); > > switch (ret) { > case -EPROBE_DEFER: > /* Driver requested deferred probing */ > dev_dbg(dev, "Driver %s requests probe deferral\n", drv->name); > driver_deferred_probe_add_trigger(dev, local_trigger_count); > break; > case -ENODEV: > case -ENXIO: > pr_debug("%s: probe of %s rejects match %d\n", > drv->name, dev_name(dev), ret); > break; > default: > /* driver matched but the probe failed */ > printk(KERN_WARNING > "%s: probe of %s failed with error %d\n", > drv->name, dev_name(dev), ret); > } > /* > * Ignore errors returned by ->probe so that the next driver can try > * its luck. > */ > ret = 0; > done: > atomic_dec(&probe_count); > wake_up(&probe_waitqueue); > return ret; > } > > diff --git a/drivers/base/dd.c b/drivers/base/dd.c > index a823f469e53f..0df9b4461766 100644 > --- a/drivers/base/dd.c > +++ b/drivers/base/dd.c > @@ -490,7 +490,7 @@ static int really_probe(struct device *dev, struct device_driver *drv) > if (dev->bus->dma_configure) { > ret = dev->bus->dma_configure(dev); > if (ret) > - goto dma_failed; > + goto probe_failed; > } > > if (driver_sysfs_add(dev)) { > @@ -546,14 +546,13 @@ static int really_probe(struct device *dev, struct device_driver *drv) > goto done; > > probe_failed: > - arch_teardown_dma_ops(dev); > -dma_failed: > if (dev->bus) > blocking_notifier_call_chain(&dev->bus->p->bus_notifier, > BUS_NOTIFY_DRIVER_NOT_BOUND, dev); > pinctrl_bind_failed: > device_links_no_driver(dev); > devres_release_all(dev); > + arch_teardown_dma_ops(dev); > driver_sysfs_remove(dev); > dev->driver = NULL; > dev_set_drvdata(dev, NULL); >
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