Please see the bisection report below about a kernel panic.
Reports aren't automatically sent to the public while we're
trialing new bisection features on kernelci.org but this one
looks valid.
See the kernel Oops due to a NULL pointer followed by a panic:
https://storage.kernelci.org/next/master/next-20200511/arm/tegra_defconfig/gcc-8/lab-collabora/baseline-tegra124-jetson-tk1.html#L573
Stack trace:
<0>[ 2.953683] [<c05624f4>] (__iommu_probe_device) from [<c05633f0>] (iommu_probe_device+0x18/0x124)
<0>[ 2.962810] [<c05633f0>] (iommu_probe_device) from [<c0566704>] (of_iommu_configure+0x154/0x1b8)
<0>[ 2.971853] [<c0566704>] (of_iommu_configure) from [<c07e9958>] (of_dma_configure+0x144/0x2c8)
<0>[ 2.980722] [<c07e9958>] (of_dma_configure) from [<c0568c24>] (host1x_attach_driver+0x148/0x2c4)
<0>[ 2.989763] [<c0568c24>] (host1x_attach_driver) from [<c0568e10>] (host1x_driver_register_full+0x70/0xcc)
<0>[ 2.999585] [<c0568e10>] (host1x_driver_register_full) from [<c102652c>] (host1x_drm_init+0x14/0x50)
<0>[ 3.008973] [<c102652c>] (host1x_drm_init) from [<c010206c>] (do_one_initcall+0x50/0x2b0)
<0>[ 3.017405] [<c010206c>] (do_one_initcall) from [<c1001000>] (kernel_init_freeable+0x188/0x200)
<0>[ 3.026361] [<c1001000>] (kernel_init_freeable) from [<c0b1808c>] (kernel_init+0x8/0x114)
<0>[ 3.034794] [<c0b1808c>] (kernel_init) from [<c01001a8>] (ret_from_fork+0x14/0x2c)
Guillaume
On 12/05/2020 02:24, kernelci.org bot wrote:
> * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
> * This automated bisection report was sent to you on the basis *
> * that you may be involved with the breaking commit it has *
> * found. No manual investigation has been done to verify it, *
> * and the root cause of the problem may be somewhere else. *
> * *
> * If you do send a fix, please include this trailer: *
> * Reported-by: "kernelci.org bot" <bot@xxxxxxxxxxxx> *
> * *
> * Hope this helps! *
> * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
>
> next/master bisection: baseline.login on jetson-tk1
>
> Summary:
> Start: 4b20e7462caa6 Add linux-next specific files for 20200511
> Plain log: https://storage.kernelci.org/next/master/next-20200511/arm/tegra_defconfig/gcc-8/lab-collabora/baseline-tegra124-jetson-tk1.txt
> HTML log: https://storage.kernelci.org/next/master/next-20200511/arm/tegra_defconfig/gcc-8/lab-collabora/baseline-tegra124-jetson-tk1.html
> Result: 3eeeb45c6d044 iommu: Remove add_device()/remove_device() code-paths
>
> Checks:
> revert: PASS
> verify: PASS
>
> Parameters:
> Tree: next
> URL: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
> Branch: master
> Target: jetson-tk1
> CPU arch: arm
> Lab: lab-collabora
> Compiler: gcc-8
> Config: tegra_defconfig
> Test case: baseline.login
>
> Breaking commit found:
>
> -------------------------------------------------------------------------------
> commit 3eeeb45c6d0444b368cdeba9bdafa8bbcf5370d1
> Author: Joerg Roedel <jroedel@xxxxxxx>
> Date: Wed Apr 29 15:37:10 2020 +0200
>
> iommu: Remove add_device()/remove_device() code-paths
>
> All drivers are converted to use the probe/release_device()
> call-backs, so the add_device/remove_device() pointers are unused and
> the code using them can be removed.
>
> Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
> Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> Acked-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> Link: https://lore.kernel.org/r/20200429133712.31431-33-joro@xxxxxxxxxx
> Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
>
> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
> index 397fd4fd0c320..7f99e5ae432c6 100644
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -220,12 +220,20 @@ static int __iommu_probe_device(struct device *dev, struct list_head *group_list
> return ret;
> }
>
> -static int __iommu_probe_device_helper(struct device *dev)
> +int iommu_probe_device(struct device *dev)
> {
> const struct iommu_ops *ops = dev->bus->iommu_ops;
> struct iommu_group *group;
> int ret;
>
> + if (!dev_iommu_get(dev))
> + return -ENOMEM;
> +
> + if (!try_module_get(ops->owner)) {
> + ret = -EINVAL;
> + goto err_out;
> + }
> +
> ret = __iommu_probe_device(dev, NULL);
> if (ret)
> goto err_out;
> @@ -259,75 +267,23 @@ static int __iommu_probe_device_helper(struct device *dev)
>
> err_release:
> iommu_release_device(dev);
> +
> err_out:
> return ret;
>
> }
>
> -int iommu_probe_device(struct device *dev)
> +void iommu_release_device(struct device *dev)
> {
> const struct iommu_ops *ops = dev->bus->iommu_ops;
> - struct iommu_group *group;
> - int ret;
> -
> - WARN_ON(dev->iommu_group);
> -
> - if (!ops)
> - return -EINVAL;
> -
> - if (!dev_iommu_get(dev))
> - return -ENOMEM;
> -
> - if (!try_module_get(ops->owner)) {
> - ret = -EINVAL;
> - goto err_free_dev_param;
> - }
> -
> - if (ops->probe_device)
> - return __iommu_probe_device_helper(dev);
> -
> - ret = ops->add_device(dev);
> - if (ret)
> - goto err_module_put;
>
> - group = iommu_group_get(dev);
> - iommu_create_device_direct_mappings(group, dev);
> - iommu_group_put(group);
> -
> - if (ops->probe_finalize)
> - ops->probe_finalize(dev);
> -
> - return 0;
> -
> -err_module_put:
> - module_put(ops->owner);
> -err_free_dev_param:
> - dev_iommu_free(dev);
> - return ret;
> -}
> -
> -static void __iommu_release_device(struct device *dev)
> -{
> - const struct iommu_ops *ops = dev->bus->iommu_ops;
> + if (!dev->iommu)
> + return;
>
> iommu_device_unlink(dev->iommu->iommu_dev, dev);
> -
> iommu_group_remove_device(dev);
>
> ops->release_device(dev);
> -}
> -
> -void iommu_release_device(struct device *dev)
> -{
> - const struct iommu_ops *ops = dev->bus->iommu_ops;
> -
> - if (!dev->iommu)
> - return;
> -
> - if (ops->release_device)
> - __iommu_release_device(dev);
> - else if (dev->iommu_group)
> - ops->remove_device(dev);
>
> module_put(ops->owner);
> dev_iommu_free(dev);
> @@ -1560,23 +1516,6 @@ struct iommu_group *iommu_group_get_for_dev(struct device *dev)
> if (ret)
> goto out_put_group;
>
> - /*
> - * Try to allocate a default domain - needs support from the
> - * IOMMU driver. There are still some drivers which don't support
> - * default domains, so the return value is not yet checked. Only
> - * allocate the domain here when the driver still has the
> - * add_device/remove_device call-backs implemented.
> - */
> - if (!ops->probe_device) {
> - iommu_alloc_default_domain(dev);
> -
> - if (group->default_domain)
> - ret = __iommu_attach_device(group->default_domain, dev);
> -
> - if (ret)
> - goto out_put_group;
> - }
> -
> return group;
>
> out_put_group:
> @@ -1591,21 +1530,6 @@ struct iommu_domain *iommu_group_default_domain(struct iommu_group *group)
> return group->default_domain;
> }
>
> -static int add_iommu_group(struct device *dev, void *data)
> -{
> - int ret = iommu_probe_device(dev);
> -
> - /*
> - * We ignore -ENODEV errors for now, as they just mean that the
> - * device is not translated by an IOMMU. We still care about
> - * other errors and fail to initialize when they happen.
> - */
> - if (ret == -ENODEV)
> - ret = 0;
> -
> - return ret;
> -}
> -
> static int probe_iommu_group(struct device *dev, void *data)
> {
> const struct iommu_ops *ops = dev->bus->iommu_ops;
> @@ -1793,47 +1717,41 @@ static int iommu_group_create_direct_mappings(struct iommu_group *group)
>
> int bus_iommu_probe(struct bus_type *bus)
> {
> - const struct iommu_ops *ops = bus->iommu_ops;
> + struct iommu_group *group, *next;
> + LIST_HEAD(group_list);
> int ret;
>
> - if (ops->probe_device) {
> - struct iommu_group *group, *next;
> - LIST_HEAD(group_list);
> -
> - /*
> - * This code-path does not allocate the default domain when
> - * creating the iommu group, so do it after the groups are
> - * created.
> - */
> - ret = bus_for_each_dev(bus, NULL, &group_list, probe_iommu_group);
> - if (ret)
> - return ret;
> + /*
> + * This code-path does not allocate the default domain when
> + * creating the iommu group, so do it after the groups are
> + * created.
> + */
> + ret = bus_for_each_dev(bus, NULL, &group_list, probe_iommu_group);
> + if (ret)
> + return ret;
>
> - list_for_each_entry_safe(group, next, &group_list, entry) {
> - /* Remove item from the list */
> - list_del_init(&group->entry);
> + list_for_each_entry_safe(group, next, &group_list, entry) {
> + /* Remove item from the list */
> + list_del_init(&group->entry);
>
> - mutex_lock(&group->mutex);
> + mutex_lock(&group->mutex);
>
> - /* Try to allocate default domain */
> - probe_alloc_default_domain(bus, group);
> + /* Try to allocate default domain */
> + probe_alloc_default_domain(bus, group);
>
> - if (!group->default_domain) {
> - mutex_unlock(&group->mutex);
> - continue;
> - }
> + if (!group->default_domain) {
> + mutex_unlock(&group->mutex);
> + continue;
> + }
>
> - iommu_group_create_direct_mappings(group);
> + iommu_group_create_direct_mappings(group);
>
> - ret = __iommu_group_dma_attach(group);
> + ret = __iommu_group_dma_attach(group);
>
> - mutex_unlock(&group->mutex);
> + mutex_unlock(&group->mutex);
>
> - if (ret)
> - break;
> - }
> - } else {
> - ret = bus_for_each_dev(bus, NULL, NULL, add_iommu_group);
> + if (ret)
> + break;
> }
>
> return ret;
> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
> index fea1622408adb..dd076366383fc 100644
> --- a/include/linux/iommu.h
> +++ b/include/linux/iommu.h
> @@ -223,8 +223,6 @@ struct iommu_iotlb_gather {
> * @iotlb_sync: Flush all queued ranges from the hardware TLBs and empty flush
> * queue
> * @iova_to_phys: translate iova to physical address
> - * @add_device: add device to iommu grouping
> - * @remove_device: remove device from iommu grouping
> * @probe_device: Add device to iommu driver handling
> * @release_device: Remove device from iommu driver handling
> * @probe_finalize: Do final setup work after the device is added to an IOMMU
> @@ -277,8 +275,6 @@ struct iommu_ops {
> void (*iotlb_sync)(struct iommu_domain *domain,
> struct iommu_iotlb_gather *iotlb_gather);
> phys_addr_t (*iova_to_phys)(struct iommu_domain *domain, dma_addr_t iova);
> - int (*add_device)(struct device *dev);
> - void (*remove_device)(struct device *dev);
> struct iommu_device *(*probe_device)(struct device *dev);
> void (*release_device)(struct device *dev);
> void (*probe_finalize)(struct device *dev);
> -------------------------------------------------------------------------------
>
>
> Git bisection log:
>
> -------------------------------------------------------------------------------
> git bisect start
> # good: [2ef96a5bb12be62ef75b5828c0aab838ebb29cb8] Linux 5.7-rc5
> git bisect good 2ef96a5bb12be62ef75b5828c0aab838ebb29cb8
> # bad: [4b20e7462caa697f8a2cdab04ed8a5881cc65427] Add linux-next specific files for 20200511
> git bisect bad 4b20e7462caa697f8a2cdab04ed8a5881cc65427
> # good: [8d06abbd3c806aa7b5a25a3ae455349b88f1ee85] Merge remote-tracking branch 'crypto/master'
> git bisect good 8d06abbd3c806aa7b5a25a3ae455349b88f1ee85
> # bad: [ee471063218348604d1ce36984ca912fa1bfd42f] Merge remote-tracking branch 'spi/for-next'
> git bisect bad ee471063218348604d1ce36984ca912fa1bfd42f
> # good: [0a7a42754678fd20454c8b376922dac9a88d67e0] Merge remote-tracking branch 'drm/drm-next'
> git bisect good 0a7a42754678fd20454c8b376922dac9a88d67e0
> # good: [c3ffe334cbcf35024f0744d3a173443d5dfed164] Merge remote-tracking branch 'modules/modules-next'
> git bisect good c3ffe334cbcf35024f0744d3a173443d5dfed164
> # good: [859687014bb39409b351aba56fb3fd58571b003b] Merge remote-tracking branch 'battery/for-next'
> git bisect good 859687014bb39409b351aba56fb3fd58571b003b
> # bad: [4446915af3dd417222fe56c0fa77bc6eefa4449b] Merge remote-tracking branch 'audit/next'
> git bisect bad 4446915af3dd417222fe56c0fa77bc6eefa4449b
> # good: [bdf4ae4c3f5fcd95a9405f1484da496b8d80ba01] Merge remote-tracking branch 'selinux/next'
> git bisect good bdf4ae4c3f5fcd95a9405f1484da496b8d80ba01
> # good: [b287ba73789906fc4f4ee821e1014b13e2814849] iommu/tegra: Convert to probe/release_device() call-backs
> git bisect good b287ba73789906fc4f4ee821e1014b13e2814849
> # bad: [a1ae3ea82d8be294d3399c6bd288d7a45890b4fc] Merge branches 'iommu/fixes' and 'core' into next
> git bisect bad a1ae3ea82d8be294d3399c6bd288d7a45890b4fc
> # good: [66ae88e71ecb93bafaacaeef233971eacd10e749] iommu/exynos: Use first SYSMMU in controllers list for IOMMU core
> git bisect good 66ae88e71ecb93bafaacaeef233971eacd10e749
> # bad: [3eeeb45c6d0444b368cdeba9bdafa8bbcf5370d1] iommu: Remove add_device()/remove_device() code-paths
> git bisect bad 3eeeb45c6d0444b368cdeba9bdafa8bbcf5370d1
> # good: [3c51c05479c577ea4235d46366d6181a2d6aff2d] iommu/exynos: Convert to probe/release_device() call-backs
> git bisect good 3c51c05479c577ea4235d46366d6181a2d6aff2d
> # first bad commit: [3eeeb45c6d0444b368cdeba9bdafa8bbcf5370d1] iommu: Remove add_device()/remove_device() code-paths
> -------------------------------------------------------------------------------
>
