| Message ID | 20180308185046.GA22796@amd (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 08/03/18 18:50, Pavel Machek wrote: > Hi! > >>> * Pavel Machek <pavel@ucw.cz> [180308 14:31]: >>>> Hi! >>>> >>>> I'm getting this warning... Has anyone seen/debugged that before? >>>> Unfortunately the backtrace does not seem to be too useful :-(. >>> >>> Adding Suman to Cc, as it points to arm_iommu_release_mapping(). >> >> Hmm, we need to find out if the failure paths in isp_probe() are >> mismatched, or if this is coming from some mismatch between the OMAP >> IOMMU driver and the DMA plumbing. AFAIK, the cleanup paths in this > > Well, camera only started to work on N900 pretty recently. Let me add > some debug printks... > > Camera does not work in 4.16.0-rc4-next-20180308-dirty. > > I see this. It looks like problem in isp error paths, indeed: Well, there certainly seems to be an obvious bug wherein isp_detach_iommu() just releases the mapping directly without calling arm_iommu_detach_device() to balance the equivalent attach. That can't be helping. Robin. > > [ 1.672210] bus: 'platform': driver_probe_device: matched device > 480bc000.isp with dr > iver omap3isp > [ 1.681976] isp_probe: 1 > [ 1.684906] isp_probe: 2 > [ 1.687591] isp_probe: 3 > [ 1.690338] isp_probe: 4 > [ 1.693054] omap3isp 480bc000.isp: 480bc000.isp supply vdd-csiphy1 > not found, using d > ummy regulator > [ 1.702728] omap3isp 480bc000.isp: 480bc000.isp supply vdd-csiphy2 > not found, using d > ummy regulator > [ 1.712402] isp_probe: 5 > [ 1.715393] omap3isp 480bc000.isp: Revision 2.0 found > [ 1.720794] isp_probe: 6 > [ 1.723815] isp_probe: 7 > [ 1.726715] omap-iommu 480bd400.mmu: 480bd400.mmu: version 1.1 > [ 1.732849] isp_probe: 8 > [ 1.735656] isp_probe: 9 > [ 1.738403] isp_probe: 10 > [ 1.741241] isp_probe: f3 > [ 1.744018] iommu_release_mapping... ce4d9500 ce4d949c > [ 1.749450] iommu_release_mapping... ok > [ 1.753479] isp_probe: f4 > [ 1.756286] clk_unregister: unregistering prepared clock: cam_xclka > [ 1.762878] clk_unregister: unregistering prepared clock: cam_xclkb > [ 1.769500] isp_probe: f5 > [ 1.772430] iommu_release_mapping... ce4d9500 ce4d949c > [ 1.777862] ------------[ cut here ]------------ > [ 1.782745] WARNING: CPU: 0 PID: 1 at lib/refcount.c:187 > refcount_sub_and_test+0x94/0 > xa8 > [ 1.791290] refcount_t: underflow; use-after-free. > [ 1.796356] Modules linked in: > [ 1.799591] CPU: 0 PID: 1 Comm: swapper Not tainted > 4.16.0-rc4-next-20180308-dirty #7 > 3 > [ 1.807922] Hardware name: Nokia RX-51 board > [ 1.812469] [<c010d6cc>] (unwind_backtrace) from [<c010b568>] > (show_stack+0x10/0x14) > [ 1.820648] [<c010b568>] (show_stack) from [<c0127df4>] > (__warn+0xe8/0x110) > ... > [ 1.968688] iommu_release_mapping... ok > [ 1.973754] bus: 'platform': driver_probe_device: matched device > n900-battery with driver rx51-battery > [ 1.984436] bus: 'platform': driver_probe_device: matched device > 48002524.bandgap with driver ti-soc-thermal > > diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c > index 8c398fe..16f4c69 100644 > --- a/arch/arm/mm/dma-mapping.c > +++ b/arch/arm/mm/dma-mapping.c > @@ -2251,8 +2251,11 @@ static int extend_iommu_mapping(struct dma_iommu_mapping *mapping) > > void arm_iommu_release_mapping(struct dma_iommu_mapping *mapping) > { > + printk("iommu_release_mapping... %lx %lx\n", mapping, mapping->domain); > if (mapping) > kref_put(&mapping->kref, release_iommu_mapping); > + printk("iommu_release_mapping... ok\n"); > + > } > EXPORT_SYMBOL_GPL(arm_iommu_release_mapping); > > diff --git a/drivers/media/platform/omap3isp/isp.c b/drivers/media/platform/omap3isp/isp.c > index 8eb000e..4d58683 100644 > --- a/drivers/media/platform/omap3isp/isp.c > +++ b/drivers/media/platform/omap3isp/isp.c > @@ -2193,12 +2193,14 @@ static int isp_probe(struct platform_device *pdev) > int ret; > int i, m; > > + printk("isp_probe: 1\n"); > isp = devm_kzalloc(&pdev->dev, sizeof(*isp), GFP_KERNEL); > if (!isp) { > dev_err(&pdev->dev, "could not allocate memory\n"); > return -ENOMEM; > } > > + printk("isp_probe: 2\n"); > ret = fwnode_property_read_u32(of_fwnode_handle(pdev->dev.of_node), > "ti,phy-type", &isp->phy_type); > if (ret) > @@ -2219,6 +2221,8 @@ static int isp_probe(struct platform_device *pdev) > mutex_init(&isp->isp_mutex); > spin_lock_init(&isp->stat_lock); > > + printk("isp_probe: 3\n"); > + > ret = v4l2_async_notifier_parse_fwnode_endpoints( > &pdev->dev, &isp->notifier, sizeof(struct isp_async_subdev), > isp_fwnode_parse); > @@ -2232,6 +2236,7 @@ static int isp_probe(struct platform_device *pdev) > if (ret) > goto error; > > + printk("isp_probe: 4\n"); > platform_set_drvdata(pdev, isp); > > /* Regulators */ > @@ -2258,6 +2263,7 @@ static int isp_probe(struct platform_device *pdev) > return PTR_ERR(isp->mmio_base[map_idx]); > } > > + printk("isp_probe: 5\n"); > ret = isp_get_clocks(isp); > if (ret < 0) > goto error; > @@ -2277,6 +2283,7 @@ static int isp_probe(struct platform_device *pdev) > goto error; > } > > + printk("isp_probe: 6\n"); > ret = isp_reset(isp); > if (ret < 0) > goto error_isp; > @@ -2306,6 +2313,7 @@ static int isp_probe(struct platform_device *pdev) > isp->mmio_base[OMAP3_ISP_IOMEM_CSI2A_REGS1] > + isp_res_maps[m].offset[i]; > > + printk("isp_probe: 7\n"); > isp->mmio_hist_base_phys = > mem->start + isp_res_maps[m].offset[OMAP3_ISP_IOMEM_HIST]; > > @@ -2316,6 +2324,8 @@ static int isp_probe(struct platform_device *pdev) > goto error_isp; > } > > + printk("isp_probe: 8\n"); > + > /* Interrupt */ > ret = platform_get_irq(pdev, 0); > if (ret <= 0) { > @@ -2325,6 +2335,7 @@ static int isp_probe(struct platform_device *pdev) > } > isp->irq_num = ret; > > + printk("isp_probe: 9\n"); > if (devm_request_irq(isp->dev, isp->irq_num, isp_isr, IRQF_SHARED, > "OMAP3 ISP", isp)) { > dev_err(isp->dev, "Unable to request IRQ\n"); > @@ -2332,6 +2343,7 @@ static int isp_probe(struct platform_device *pdev) > goto error_iommu; > } > > + printk("isp_probe: 10\n"); > /* Entities */ > ret = isp_initialize_modules(isp); > if (ret < 0) > @@ -2345,27 +2357,35 @@ static int isp_probe(struct platform_device *pdev) > if (ret < 0) > goto error_register_entities; > > + printk("isp_probe: 11\n"); > isp->notifier.ops = &isp_subdev_notifier_ops; > > ret = v4l2_async_notifier_register(&isp->v4l2_dev, &isp->notifier); > if (ret) > goto error_register_entities; > > + printk("isp_probe: 12\n"); > isp_core_init(isp, 1); > + printk("isp_probe: 13\n"); > omap3isp_put(isp); > > return 0; > > error_register_entities: > + printk("isp_probe: f1\n"); > isp_unregister_entities(isp); > error_modules: > + printk("isp_probe: f2\n"); > isp_cleanup_modules(isp); > error_iommu: > + printk("isp_probe: f3\n"); > isp_detach_iommu(isp); > error_isp: > + printk("isp_probe: f4\n"); > isp_xclk_cleanup(isp); > __omap3isp_put(isp, false); > error: > + printk("isp_probe: f5\n"); > v4l2_async_notifier_cleanup(&isp->notifier); > mutex_destroy(&isp->isp_mutex); > > > > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >
On 03/09/2018 06:08 AM, Robin Murphy wrote: > On 08/03/18 18:50, Pavel Machek wrote: >> Hi! >> >>>> * Pavel Machek <pavel@ucw.cz> [180308 14:31]: >>>>> Hi! >>>>> >>>>> I'm getting this warning... Has anyone seen/debugged that before? >>>>> Unfortunately the backtrace does not seem to be too useful :-(. >>>> >>>> Adding Suman to Cc, as it points to arm_iommu_release_mapping(). >>> >>> Hmm, we need to find out if the failure paths in isp_probe() are >>> mismatched, or if this is coming from some mismatch between the OMAP >>> IOMMU driver and the DMA plumbing. AFAIK, the cleanup paths in this >> >> Well, camera only started to work on N900 pretty recently. Let me add >> some debug printks... >> >> Camera does not work in 4.16.0-rc4-next-20180308-dirty. >> >> I see this. It looks like problem in isp error paths, indeed: > > Well, there certainly seems to be an obvious bug wherein > isp_detach_iommu() just releases the mapping directly without calling > arm_iommu_detach_device() to balance the equivalent attach. That can't > be helping. Indeed, I have been able to reproduce the same warning using a standalone test module, and the missing arm_iommu_detach_device() is causing the warning after probe (during failure path) or during remove. regards Suman > > Robin. > >> >> [ 1.672210] bus: 'platform': driver_probe_device: matched device >> 480bc000.isp with dr >> iver omap3isp >> [ 1.681976] isp_probe: 1 >> [ 1.684906] isp_probe: 2 >> [ 1.687591] isp_probe: 3 >> [ 1.690338] isp_probe: 4 >> [ 1.693054] omap3isp 480bc000.isp: 480bc000.isp supply vdd-csiphy1 >> not found, using d >> ummy regulator >> [ 1.702728] omap3isp 480bc000.isp: 480bc000.isp supply vdd-csiphy2 >> not found, using d >> ummy regulator >> [ 1.712402] isp_probe: 5 >> [ 1.715393] omap3isp 480bc000.isp: Revision 2.0 found >> [ 1.720794] isp_probe: 6 >> [ 1.723815] isp_probe: 7 >> [ 1.726715] omap-iommu 480bd400.mmu: 480bd400.mmu: version 1.1 >> [ 1.732849] isp_probe: 8 >> [ 1.735656] isp_probe: 9 >> [ 1.738403] isp_probe: 10 >> [ 1.741241] isp_probe: f3 >> [ 1.744018] iommu_release_mapping... ce4d9500 ce4d949c >> [ 1.749450] iommu_release_mapping... ok >> [ 1.753479] isp_probe: f4 >> [ 1.756286] clk_unregister: unregistering prepared clock: cam_xclka >> [ 1.762878] clk_unregister: unregistering prepared clock: cam_xclkb >> [ 1.769500] isp_probe: f5 >> [ 1.772430] iommu_release_mapping... ce4d9500 ce4d949c >> [ 1.777862] ------------[ cut here ]------------ >> [ 1.782745] WARNING: CPU: 0 PID: 1 at lib/refcount.c:187 >> refcount_sub_and_test+0x94/0 >> xa8 >> [ 1.791290] refcount_t: underflow; use-after-free. >> [ 1.796356] Modules linked in: >> [ 1.799591] CPU: 0 PID: 1 Comm: swapper Not tainted >> 4.16.0-rc4-next-20180308-dirty #7 >> 3 >> [ 1.807922] Hardware name: Nokia RX-51 board >> [ 1.812469] [<c010d6cc>] (unwind_backtrace) from [<c010b568>] >> (show_stack+0x10/0x14) >> [ 1.820648] [<c010b568>] (show_stack) from [<c0127df4>] >> (__warn+0xe8/0x110) >> ... >> [ 1.968688] iommu_release_mapping... ok >> [ 1.973754] bus: 'platform': driver_probe_device: matched device >> n900-battery with driver rx51-battery >> [ 1.984436] bus: 'platform': driver_probe_device: matched device >> 48002524.bandgap with driver ti-soc-thermal >> >> diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c >> index 8c398fe..16f4c69 100644 >> --- a/arch/arm/mm/dma-mapping.c >> +++ b/arch/arm/mm/dma-mapping.c >> @@ -2251,8 +2251,11 @@ static int extend_iommu_mapping(struct >> dma_iommu_mapping *mapping) >> void arm_iommu_release_mapping(struct dma_iommu_mapping *mapping) >> { >> + printk("iommu_release_mapping... %lx %lx\n", mapping, >> mapping->domain); >> if (mapping) >> kref_put(&mapping->kref, release_iommu_mapping); >> + printk("iommu_release_mapping... ok\n"); >> + >> } >> EXPORT_SYMBOL_GPL(arm_iommu_release_mapping); >> diff --git a/drivers/media/platform/omap3isp/isp.c >> b/drivers/media/platform/omap3isp/isp.c >> index 8eb000e..4d58683 100644 >> --- a/drivers/media/platform/omap3isp/isp.c >> +++ b/drivers/media/platform/omap3isp/isp.c >> @@ -2193,12 +2193,14 @@ static int isp_probe(struct platform_device >> *pdev) >> int ret; >> int i, m; >> + printk("isp_probe: 1\n"); >> isp = devm_kzalloc(&pdev->dev, sizeof(*isp), GFP_KERNEL); >> if (!isp) { >> dev_err(&pdev->dev, "could not allocate memory\n"); >> return -ENOMEM; >> } >> + printk("isp_probe: 2\n"); >> ret = fwnode_property_read_u32(of_fwnode_handle(pdev->dev.of_node), >> "ti,phy-type", &isp->phy_type); >> if (ret) >> @@ -2219,6 +2221,8 @@ static int isp_probe(struct platform_device *pdev) >> mutex_init(&isp->isp_mutex); >> spin_lock_init(&isp->stat_lock); >> + printk("isp_probe: 3\n"); >> + >> ret = v4l2_async_notifier_parse_fwnode_endpoints( >> &pdev->dev, &isp->notifier, sizeof(struct isp_async_subdev), >> isp_fwnode_parse); >> @@ -2232,6 +2236,7 @@ static int isp_probe(struct platform_device *pdev) >> if (ret) >> goto error; >> + printk("isp_probe: 4\n"); >> platform_set_drvdata(pdev, isp); >> /* Regulators */ >> @@ -2258,6 +2263,7 @@ static int isp_probe(struct platform_device *pdev) >> return PTR_ERR(isp->mmio_base[map_idx]); >> } >> + printk("isp_probe: 5\n"); >> ret = isp_get_clocks(isp); >> if (ret < 0) >> goto error; >> @@ -2277,6 +2283,7 @@ static int isp_probe(struct platform_device *pdev) >> goto error; >> } >> + printk("isp_probe: 6\n"); >> ret = isp_reset(isp); >> if (ret < 0) >> goto error_isp; >> @@ -2306,6 +2313,7 @@ static int isp_probe(struct platform_device *pdev) >> isp->mmio_base[OMAP3_ISP_IOMEM_CSI2A_REGS1] >> + isp_res_maps[m].offset[i]; >> + printk("isp_probe: 7\n"); >> isp->mmio_hist_base_phys = >> mem->start + isp_res_maps[m].offset[OMAP3_ISP_IOMEM_HIST]; >> @@ -2316,6 +2324,8 @@ static int isp_probe(struct platform_device >> *pdev) >> goto error_isp; >> } >> + printk("isp_probe: 8\n"); >> + >> /* Interrupt */ >> ret = platform_get_irq(pdev, 0); >> if (ret <= 0) { >> @@ -2325,6 +2335,7 @@ static int isp_probe(struct platform_device *pdev) >> } >> isp->irq_num = ret; >> + printk("isp_probe: 9\n"); >> if (devm_request_irq(isp->dev, isp->irq_num, isp_isr, IRQF_SHARED, >> "OMAP3 ISP", isp)) { >> dev_err(isp->dev, "Unable to request IRQ\n"); >> @@ -2332,6 +2343,7 @@ static int isp_probe(struct platform_device *pdev) >> goto error_iommu; >> } >> + printk("isp_probe: 10\n"); >> /* Entities */ >> ret = isp_initialize_modules(isp); >> if (ret < 0) >> @@ -2345,27 +2357,35 @@ static int isp_probe(struct platform_device >> *pdev) >> if (ret < 0) >> goto error_register_entities; >> + printk("isp_probe: 11\n"); >> isp->notifier.ops = &isp_subdev_notifier_ops; >> ret = v4l2_async_notifier_register(&isp->v4l2_dev, >> &isp->notifier); >> if (ret) >> goto error_register_entities; >> + printk("isp_probe: 12\n"); >> isp_core_init(isp, 1); >> + printk("isp_probe: 13\n"); >> omap3isp_put(isp); >> return 0; >> error_register_entities: >> + printk("isp_probe: f1\n"); >> isp_unregister_entities(isp); >> error_modules: >> + printk("isp_probe: f2\n"); >> isp_cleanup_modules(isp); >> error_iommu: >> + printk("isp_probe: f3\n"); >> isp_detach_iommu(isp); >> error_isp: >> + printk("isp_probe: f4\n"); >> isp_xclk_cleanup(isp); >> __omap3isp_put(isp, false); >> error: >> + printk("isp_probe: f5\n"); >> v4l2_async_notifier_cleanup(&isp->notifier); >> mutex_destroy(&isp->isp_mutex); >> >> >> >> >> _______________________________________________ >> linux-arm-kernel mailing list >> linux-arm-kernel@lists.infradead.org >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >>
On Fri 2018-03-09 16:13:36, Suman Anna wrote: > On 03/09/2018 06:08 AM, Robin Murphy wrote: > > On 08/03/18 18:50, Pavel Machek wrote: > >> Hi! > >> > >>>> * Pavel Machek <pavel@ucw.cz> [180308 14:31]: > >>>>> Hi! > >>>>> > >>>>> I'm getting this warning... Has anyone seen/debugged that before? > >>>>> Unfortunately the backtrace does not seem to be too useful :-(. > >>>> > >>>> Adding Suman to Cc, as it points to arm_iommu_release_mapping(). > >>> > >>> Hmm, we need to find out if the failure paths in isp_probe() are > >>> mismatched, or if this is coming from some mismatch between the OMAP > >>> IOMMU driver and the DMA plumbing. AFAIK, the cleanup paths in this > >> > >> Well, camera only started to work on N900 pretty recently. Let me add > >> some debug printks... > >> > >> Camera does not work in 4.16.0-rc4-next-20180308-dirty. > >> > >> I see this. It looks like problem in isp error paths, indeed: > > > > Well, there certainly seems to be an obvious bug wherein > > isp_detach_iommu() just releases the mapping directly without calling > > arm_iommu_detach_device() to balance the equivalent attach. That can't > > be helping. > > Indeed, I have been able to reproduce the same warning using a > standalone test module, and the missing arm_iommu_detach_device() is > causing the warning after probe (during failure path) or during > remove. Ok do you have an idea how to fix the isp error paths? Untested patch would be fine... But it seems that you know what needs to be fixed and I don't. Pavel
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 8c398fe..16f4c69 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -2251,8 +2251,11 @@ static int extend_iommu_mapping(struct dma_iommu_mapping *mapping) void arm_iommu_release_mapping(struct dma_iommu_mapping *mapping) { + printk("iommu_release_mapping... %lx %lx\n", mapping, mapping->domain); if (mapping) kref_put(&mapping->kref, release_iommu_mapping); + printk("iommu_release_mapping... ok\n"); + } EXPORT_SYMBOL_GPL(arm_iommu_release_mapping); diff --git a/drivers/media/platform/omap3isp/isp.c b/drivers/media/platform/omap3isp/isp.c index 8eb000e..4d58683 100644 --- a/drivers/media/platform/omap3isp/isp.c +++ b/drivers/media/platform/omap3isp/isp.c @@ -2193,12 +2193,14 @@ static int isp_probe(struct platform_device *pdev) int ret; int i, m; + printk("isp_probe: 1\n"); isp = devm_kzalloc(&pdev->dev, sizeof(*isp), GFP_KERNEL); if (!isp) { dev_err(&pdev->dev, "could not allocate memory\n"); return -ENOMEM; } + printk("isp_probe: 2\n"); ret = fwnode_property_read_u32(of_fwnode_handle(pdev->dev.of_node), "ti,phy-type", &isp->phy_type); if (ret) @@ -2219,6 +2221,8 @@ static int isp_probe(struct platform_device *pdev) mutex_init(&isp->isp_mutex); spin_lock_init(&isp->stat_lock); + printk("isp_probe: 3\n"); + ret = v4l2_async_notifier_parse_fwnode_endpoints( &pdev->dev, &isp->notifier, sizeof(struct isp_async_subdev), isp_fwnode_parse); @@ -2232,6 +2236,7 @@ static int isp_probe(struct platform_device *pdev) if (ret) goto error; + printk("isp_probe: 4\n"); platform_set_drvdata(pdev, isp); /* Regulators */ @@ -2258,6 +2263,7 @@ static int isp_probe(struct platform_device *pdev) return PTR_ERR(isp->mmio_base[map_idx]); } + printk("isp_probe: 5\n"); ret = isp_get_clocks(isp); if (ret < 0) goto error; @@ -2277,6 +2283,7 @@ static int isp_probe(struct platform_device *pdev) goto error; } + printk("isp_probe: 6\n"); ret = isp_reset(isp); if (ret < 0) goto error_isp; @@ -2306,6 +2313,7 @@ static int isp_probe(struct platform_device *pdev) isp->mmio_base[OMAP3_ISP_IOMEM_CSI2A_REGS1] + isp_res_maps[m].offset[i]; + printk("isp_probe: 7\n"); isp->mmio_hist_base_phys = mem->start + isp_res_maps[m].offset[OMAP3_ISP_IOMEM_HIST]; @@ -2316,6 +2324,8 @@ static int isp_probe(struct platform_device *pdev) goto error_isp; } + printk("isp_probe: 8\n"); + /* Interrupt */ ret = platform_get_irq(pdev, 0); if (ret <= 0) { @@ -2325,6 +2335,7 @@ static int isp_probe(struct platform_device *pdev) } isp->irq_num = ret; + printk("isp_probe: 9\n"); if (devm_request_irq(isp->dev, isp->irq_num, isp_isr, IRQF_SHARED, "OMAP3 ISP", isp)) { dev_err(isp->dev, "Unable to request IRQ\n"); @@ -2332,6 +2343,7 @@ static int isp_probe(struct platform_device *pdev) goto error_iommu; } + printk("isp_probe: 10\n"); /* Entities */ ret = isp_initialize_modules(isp); if (ret < 0) @@ -2345,27 +2357,35 @@ static int isp_probe(struct platform_device *pdev) if (ret < 0) goto error_register_entities; + printk("isp_probe: 11\n"); isp->notifier.ops = &isp_subdev_notifier_ops; ret = v4l2_async_notifier_register(&isp->v4l2_dev, &isp->notifier); if (ret) goto error_register_entities; + printk("isp_probe: 12\n"); isp_core_init(isp, 1); + printk("isp_probe: 13\n"); omap3isp_put(isp); return 0; error_register_entities: + printk("isp_probe: f1\n"); isp_unregister_entities(isp); error_modules: + printk("isp_probe: f2\n"); isp_cleanup_modules(isp); error_iommu: + printk("isp_probe: f3\n"); isp_detach_iommu(isp); error_isp: + printk("isp_probe: f4\n"); isp_xclk_cleanup(isp); __omap3isp_put(isp, false); error: + printk("isp_probe: f5\n"); v4l2_async_notifier_cleanup(&isp->notifier); mutex_destroy(&isp->isp_mutex);