Linaro-mm-sig November 2022

linaro-mm-sig@lists.linaro.org

48 participants
35 discussions

[PATCH v4] dma-buf: fix racing conflict of dma_heap_add()

by Dawei Li

Racing conflict could be: task A task B list_for_each_entry strcmp(h->name)) list_for_each_entry strcmp(h->name) kzalloc kzalloc ...... ..... device_create device_create list_add list_add The root cause is that task B has no idea about the fact someone else(A) has inserted heap with same name when it calls list_add, so a potential collision occurs. Fixes: c02a81fba74f ("dma-buf: Add dma-buf heaps framework") Signed-off-by: Dawei Li <set_pte_at(a)outlook.com> --- v1: https://lore.kernel.org/all/TYCP286MB2323950197F60FC3473123B7CA349@TYCP286M… v1->v2: Narrow down locking scope, check the existence of heap before insertion, as suggested by Andrew Davis. v2->v3: Remove double checking. v3->v4: Minor coding style and patch formatting adjustment. --- drivers/dma-buf/dma-heap.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) diff --git a/drivers/dma-buf/dma-heap.c b/drivers/dma-buf/dma-heap.c index 8f5848aa144f..59d158873f4c 100644 --- a/drivers/dma-buf/dma-heap.c +++ b/drivers/dma-buf/dma-heap.c @@ -233,18 +233,6 @@ struct dma_heap *dma_heap_add(const struct dma_heap_export_info *exp_info) return ERR_PTR(-EINVAL); } - /* check the name is unique */ - mutex_lock(&heap_list_lock); - list_for_each_entry(h, &heap_list, list) { - if (!strcmp(h->name, exp_info->name)) { - mutex_unlock(&heap_list_lock); - pr_err("dma_heap: Already registered heap named %s\n", - exp_info->name); - return ERR_PTR(-EINVAL); - } - } - mutex_unlock(&heap_list_lock); - heap = kzalloc(sizeof(*heap), GFP_KERNEL); if (!heap) return ERR_PTR(-ENOMEM); @@ -283,13 +271,27 @@ struct dma_heap *dma_heap_add(const struct dma_heap_export_info *exp_info) err_ret = ERR_CAST(dev_ret); goto err2; } - /* Add heap to the list */ + mutex_lock(&heap_list_lock); + /* check the name is unique */ + list_for_each_entry(h, &heap_list, list) { + if (!strcmp(h->name, exp_info->name)) { + mutex_unlock(&heap_list_lock); + pr_err("dma_heap: Already registered heap named %s\n", + exp_info->name); + err_ret = ERR_PTR(-EINVAL); + goto err3; + } + } + + /* Add heap to the list */ list_add(&heap->list, &heap_list); mutex_unlock(&heap_list_lock); return heap; +err3: + device_destroy(dma_heap_class, heap->heap_devt); err2: cdev_del(&heap->heap_cdev); err1: -- 2.25.1

2 years

[PATCH] dma-buf: Require VM_PFNMAP vma for mmap

by Daniel Vetter

tldr; DMA buffers aren't normal memory, expecting that you can use them like that (like calling get_user_pages works, or that they're accounting like any other normal memory) cannot be guaranteed. Since some userspace only runs on integrated devices, where all buffers are actually all resident system memory, there's a huge temptation to assume that a struct page is always present and useable like for any more pagecache backed mmap. This has the potential to result in a uapi nightmare. To stop this gap require that DMA buffer mmaps are VM_PFNMAP, which blocks get_user_pages and all the other struct page based infrastructure for everyone. In spirit this is the uapi counterpart to the kernel-internal CONFIG_DMABUF_DEBUG. Motivated by a recent patch which wanted to swich the system dma-buf heap to vm_insert_page instead of vm_insert_pfn. v2: Jason brought up that we also want to guarantee that all ptes have the pte_special flag set, to catch fast get_user_pages (on architectures that support this). Allowing VM_MIXEDMAP (like VM_SPECIAL does) would still allow vm_insert_page, but limiting to VM_PFNMAP will catch that. From auditing the various functions to insert pfn pte entires (vm_insert_pfn_prot, remap_pfn_range and all it's callers like dma_mmap_wc) it looks like VM_PFNMAP is already required anyway, so this should be the correct flag to check for. v3: Change to WARN_ON_ONCE (Thomas Zimmermann) References: https://lore.kernel.org/lkml/CAKMK7uHi+mG0z0HUmNt13QCCvutuRVjpcR0NjRL12k-Wb… Acked-by: Christian König <christian.koenig(a)amd.com> Acked-by: Thomas Zimmermann <tzimmermann(a)suse.de> Cc: Thomas Zimmermann <tzimmermann(a)suse.de> Cc: Jason Gunthorpe <jgg(a)ziepe.ca> Cc: Suren Baghdasaryan <surenb(a)google.com> Cc: Matthew Wilcox <willy(a)infradead.org> Cc: John Stultz <john.stultz(a)linaro.org> Signed-off-by: Daniel Vetter <daniel.vetter(a)intel.com> Cc: Sumit Semwal <sumit.semwal(a)linaro.org> Cc: "Christian König" <christian.koenig(a)amd.com> Cc: linux-media(a)vger.kernel.org Cc: linaro-mm-sig(a)lists.linaro.org -- Ok I entirely forgot about this patch but stumbled over it and checked what's up with it no. I think it's ready now for merging: - shmem helper patches to fix up vgem landed - ttm has been fixed since a while - I don't think we've had any other open issues Time to lock down this uapi contract for real? -Daniel --- drivers/dma-buf/dma-buf.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index b6c36914e7c6..88718665c3c3 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -150,6 +150,8 @@ static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma) ret = dmabuf->ops->mmap(dmabuf, vma); dma_resv_unlock(dmabuf->resv); + WARN_ON_ONCE(!(vma->vm_flags & VM_PFNMAP)); + return ret; } @@ -1495,6 +1497,8 @@ int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma, ret = dmabuf->ops->mmap(dmabuf, vma); dma_resv_unlock(dmabuf->resv); + WARN_ON_ONCE(!(vma->vm_flags & VM_PFNMAP)); + return ret; } EXPORT_SYMBOL_NS_GPL(dma_buf_mmap, DMA_BUF); -- 2.37.2

2 years

[syzbot] inconsistent lock state in sync_info_debugfs_show

by syzbot

Hello, syzbot found the following issue on: HEAD commit: 1c52283265a4 Merge branch 'akpm' (patches from Andrew) git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1224663fb00000 kernel config: https://syzkaller.appspot.com/x/.config?x=75bc179af0ff0457 dashboard link: https://syzkaller.appspot.com/bug?extid=007bfe0f3330f6e1e7d1 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+007bfe0f3330f6e1e7d1(a)syzkaller.appspotmail.com ================================ WARNING: inconsistent lock state 5.16.0-syzkaller #0 Not tainted -------------------------------- inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. syz-executor.2/18360 [HC0[0]:SC0[0]:HE0:SE1] takes: ffffffff8c712cf8 (sync_timeline_list_lock){?...}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:374 [inline] ffffffff8c712cf8 (sync_timeline_list_lock){?...}-{2:2}, at: sync_info_debugfs_show+0x2d/0x200 drivers/dma-buf/sync_debug.c:147 {IN-HARDIRQ-W} state was registered at: lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 sync_timeline_debug_remove+0x25/0x190 drivers/dma-buf/sync_debug.c:31 sync_timeline_free drivers/dma-buf/sw_sync.c:104 [inline] kref_put include/linux/kref.h:65 [inline] sync_timeline_put drivers/dma-buf/sw_sync.c:116 [inline] timeline_fence_release+0x263/0x340 drivers/dma-buf/sw_sync.c:144 dma_fence_release+0x2ee/0x590 drivers/dma-buf/dma-fence.c:549 kref_put include/linux/kref.h:65 [inline] dma_fence_put include/linux/dma-fence.h:276 [inline] dma_fence_array_release+0x1e4/0x2b0 drivers/dma-buf/dma-fence-array.c:120 dma_fence_release+0x2ee/0x590 drivers/dma-buf/dma-fence.c:549 kref_put include/linux/kref.h:65 [inline] dma_fence_put include/linux/dma-fence.h:276 [inline] irq_dma_fence_array_work+0xa5/0xd0 drivers/dma-buf/dma-fence-array.c:52 irq_work_single+0x120/0x270 kernel/irq_work.c:211 irq_work_run_list+0x91/0xc0 kernel/irq_work.c:242 irq_work_run+0x54/0xd0 kernel/irq_work.c:251 __sysvec_irq_work+0x95/0x3d0 arch/x86/kernel/irq_work.c:22 sysvec_irq_work+0x8e/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x12/0x20 arch/x86/include/asm/idtentry.h:664 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:399 [inline] sw_sync_debugfs_release+0x160/0x240 drivers/dma-buf/sw_sync.c:321 __fput+0x286/0x9f0 fs/file_table.c:311 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xb29/0x2a30 kernel/exit.c:806 do_group_exit+0xd2/0x2f0 kernel/exit.c:935 get_signal+0x4b0/0x28c0 kernel/signal.c:2862 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:288 irq event stamp: 124 hardirqs last enabled at (123): [<ffffffff894fd980>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] hardirqs last enabled at (123): [<ffffffff894fd980>] _raw_spin_unlock_irqrestore+0x50/0x70 kernel/locking/spinlock.c:194 hardirqs last disabled at (124): [<ffffffff894fd6e1>] __raw_spin_lock_irq include/linux/spinlock_api_smp.h:117 [inline] hardirqs last disabled at (124): [<ffffffff894fd6e1>] _raw_spin_lock_irq+0x41/0x50 kernel/locking/spinlock.c:170 softirqs last enabled at (116): [<ffffffff81465513>] invoke_softirq kernel/softirq.c:432 [inline] softirqs last enabled at (116): [<ffffffff81465513>] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 softirqs last disabled at (97): [<ffffffff81465513>] invoke_softirq kernel/softirq.c:432 [inline] softirqs last disabled at (97): [<ffffffff81465513>] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sync_timeline_list_lock); <Interrupt> lock(sync_timeline_list_lock); *** DEADLOCK *** 3 locks held by syz-executor.2/18360: #0: ffff88801e30c0f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:1034 #1: ffff88807a26dd58 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xdf/0x1280 fs/seq_file.c:182 #2: ffffffff8c712cf8 (sync_timeline_list_lock){?...}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:374 [inline] #2: ffffffff8c712cf8 (sync_timeline_list_lock){?...}-{2:2}, at: sync_info_debugfs_show+0x2d/0x200 drivers/dma-buf/sync_debug.c:147 stack backtrace: CPU: 0 PID: 18360 Comm: syz-executor.2 Not tainted 5.16.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_usage_bug kernel/locking/lockdep.c:203 [inline] valid_state kernel/locking/lockdep.c:3945 [inline] mark_lock_irq kernel/locking/lockdep.c:4148 [inline] mark_lock.cold+0x61/0x8e kernel/locking/lockdep.c:4605 mark_held_locks+0x9f/0xe0 kernel/locking/lockdep.c:4206 __trace_hardirqs_on_caller kernel/locking/lockdep.c:4224 [inline] lockdep_hardirqs_on_prepare kernel/locking/lockdep.c:4292 [inline] lockdep_hardirqs_on_prepare+0x135/0x400 kernel/locking/lockdep.c:4244 trace_hardirqs_on+0x5b/0x1c0 kernel/trace/trace_preemptirq.c:49 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline] _raw_spin_unlock_irq+0x1f/0x40 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:399 [inline] sync_print_obj drivers/dma-buf/sync_debug.c:118 [inline] sync_info_debugfs_show+0xeb/0x200 drivers/dma-buf/sync_debug.c:153 seq_read_iter+0x4f5/0x1280 fs/seq_file.c:230 seq_read+0x3e8/0x5c0 fs/seq_file.c:162 vfs_read+0x1b5/0x600 fs/read_write.c:479 ksys_read+0x12d/0x250 fs/read_write.c:619 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f781fb4b059 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f781e4c0168 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f781fc5df60 RCX: 00007f781fb4b059 RDX: 0000000000000008 RSI: 0000000020000140 RDI: 0000000000000003 RBP: 00007f781fba508d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff0ff6575f R14: 00007f781e4c0300 R15: 0000000000022000 </TASK> --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller(a)googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

2 years

[PATCH v2 3/3] drm/gem-shmem: When drm_gem_object_init failed, should release object

by ChunyouTang

when goto err_free, the object had init, so it should be release when fail. Signed-off-by: ChunyouTang <tangchunyou(a)163.com> --- drivers/gpu/drm/drm_gem.c | 19 ++++++++++++++++--- drivers/gpu/drm/drm_gem_shmem_helper.c | 4 +++- include/drm/drm_gem.h | 1 + 3 files changed, 20 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 8b68a3c1e6ab..3e2e660717c3 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -169,6 +169,20 @@ void drm_gem_private_object_init(struct drm_device *dev, } EXPORT_SYMBOL(drm_gem_private_object_init); +/** + * drm_gem_private_object_fini - Finalize a failed drm_gem_object + * @obj: drm_gem_object + * + * Uninitialize an already allocated GEM object when it initialized failed + */ +void drm_gem_private_object_fini(struct drm_gem_object *obj) +{ + WARN_ON(obj->dma_buf); + + dma_resv_fini(&obj->_resv); +} +EXPORT_SYMBOL(drm_gem_private_object_fini); + /** * drm_gem_object_handle_free - release resources bound to userspace handles * @obj: GEM object to clean up. @@ -930,12 +944,11 @@ drm_gem_release(struct drm_device *dev, struct drm_file *file_private) void drm_gem_object_release(struct drm_gem_object *obj) { - WARN_ON(obj->dma_buf); - if (obj->filp) fput(obj->filp); - dma_resv_fini(&obj->_resv); + drm_gem_private_object_fini(obj); + drm_gem_free_mmap_offset(obj); drm_gem_lru_remove(obj); } diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index 35138f8a375c..db73234edcbe 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -79,8 +79,10 @@ __drm_gem_shmem_create(struct drm_device *dev, size_t size, bool private) } else { ret = drm_gem_object_init(dev, obj, size); } - if (ret) + if (ret) { + drm_gem_private_object_fini(obj); goto err_free; + } ret = drm_gem_create_mmap_offset(obj); if (ret) diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index bd42f25e449c..9b1feb03069d 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -405,6 +405,7 @@ int drm_gem_object_init(struct drm_device *dev, struct drm_gem_object *obj, size_t size); void drm_gem_private_object_init(struct drm_device *dev, struct drm_gem_object *obj, size_t size); +void drm_gem_private_object_fini(struct drm_gem_object *obj); void drm_gem_vm_open(struct vm_area_struct *vma); void drm_gem_vm_close(struct vm_area_struct *vma); int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size, -- 2.25.1

2 years, 1 month

[PATCH] i2c: qcom-geni: fix error return code in geni_i2c_gpi_xfer

by Wang Yufen

Fix to return a negative error code from the gi2c->err instead of 0. Fixes: d8703554f4de ("i2c: qcom-geni: Add support for GPI DMA") Signed-off-by: Wang Yufen <wangyufen(a)huawei.com> --- drivers/i2c/busses/i2c-qcom-geni.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c index 84a7751..8fce98b 100644 --- a/drivers/i2c/busses/i2c-qcom-geni.c +++ b/drivers/i2c/busses/i2c-qcom-geni.c @@ -626,7 +626,6 @@ static int geni_i2c_gpi_xfer(struct geni_i2c_dev *gi2c, struct i2c_msg msgs[], i dev_err(gi2c->se.dev, "I2C timeout gpi flags:%d addr:0x%x\n", gi2c->cur->flags, gi2c->cur->addr); gi2c->err = -ETIMEDOUT; - goto err; } if (gi2c->err) { -- 1.8.3.1

2 years, 1 month

[PATCH 3/5] kobject: kset_uevent_ops: make filter() callback take a const *

by Greg Kroah-Hartman

The filter() callback in struct kset_uevent_ops does not modify the kobject passed into it, so make the pointer const to enforce this restriction. When doing so, fix up all existing filter() callbacks to have the correct signature to preserve the build. Cc: "Rafael J. Wysocki" <rafael(a)kernel.org> Cc: Sumit Semwal <sumit.semwal(a)linaro.org> Cc: "Christian König" <christian.koenig(a)amd.com> Cc: linux-media(a)vger.kernel.org Cc: dri-devel(a)lists.freedesktop.org Cc: linaro-mm-sig(a)lists.linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- drivers/base/bus.c | 2 +- drivers/base/core.c | 4 ++-- drivers/dma-buf/dma-buf-sysfs-stats.c | 2 +- include/linux/kobject.h | 2 +- kernel/params.c | 2 +- 5 files changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/base/bus.c b/drivers/base/bus.c index 7ca47e5b3c1f..4ec6dbab73be 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -163,7 +163,7 @@ static struct kobj_type bus_ktype = { .release = bus_release, }; -static int bus_uevent_filter(struct kobject *kobj) +static int bus_uevent_filter(const struct kobject *kobj) { const struct kobj_type *ktype = get_ktype(kobj); diff --git a/drivers/base/core.c b/drivers/base/core.c index a79b99ecf4d8..005a2b092f3e 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -2362,12 +2362,12 @@ static struct kobj_type device_ktype = { }; -static int dev_uevent_filter(struct kobject *kobj) +static int dev_uevent_filter(const struct kobject *kobj) { const struct kobj_type *ktype = get_ktype(kobj); if (ktype == &device_ktype) { - struct device *dev = kobj_to_dev(kobj); + const struct device *dev = kobj_to_dev(kobj); if (dev->bus) return 1; if (dev->class) diff --git a/drivers/dma-buf/dma-buf-sysfs-stats.c b/drivers/dma-buf/dma-buf-sysfs-stats.c index 2bba0babcb62..f69d68122b9b 100644 --- a/drivers/dma-buf/dma-buf-sysfs-stats.c +++ b/drivers/dma-buf/dma-buf-sysfs-stats.c @@ -132,7 +132,7 @@ void dma_buf_stats_teardown(struct dma_buf *dmabuf) /* Statistics files do not need to send uevents. */ -static int dmabuf_sysfs_uevent_filter(struct kobject *kobj) +static int dmabuf_sysfs_uevent_filter(const struct kobject *kobj) { return 0; } diff --git a/include/linux/kobject.h b/include/linux/kobject.h index 5a2d58e10bf5..640f59d4b3de 100644 --- a/include/linux/kobject.h +++ b/include/linux/kobject.h @@ -135,7 +135,7 @@ struct kobj_uevent_env { }; struct kset_uevent_ops { - int (* const filter)(struct kobject *kobj); + int (* const filter)(const struct kobject *kobj); const char *(* const name)(struct kobject *kobj); int (* const uevent)(struct kobject *kobj, struct kobj_uevent_env *env); }; diff --git a/kernel/params.c b/kernel/params.c index 5b92310425c5..d2237209ceda 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -926,7 +926,7 @@ static const struct sysfs_ops module_sysfs_ops = { .store = module_attr_store, }; -static int uevent_filter(struct kobject *kobj) +static int uevent_filter(const struct kobject *kobj) { const struct kobj_type *ktype = get_ktype(kobj); -- 2.38.1

2 years, 1 month

[syzbot] inconsistent lock state in mark_held_locks

by syzbot

Hello, syzbot found the following issue on: HEAD commit: e01d50cbd6ee Merge tag 'vfio-v6.1-rc6' of https://github.c.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=145f6401880000 kernel config: https://syzkaller.appspot.com/x/.config?x=e9039cbe1d7613aa dashboard link: https://syzkaller.appspot.com/bug?extid=65422ff0767f378aacfb compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/43fe73693a6c/disk-e01d50cb.raw… vmlinux: https://storage.googleapis.com/syzbot-assets/35e1240adbc1/vmlinux-e01d50cb.… kernel image: https://storage.googleapis.com/syzbot-assets/3b532cce5d0b/bzImage-e01d50cb.… IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+65422ff0767f378aacfb(a)syzkaller.appspotmail.com ================================ WARNING: inconsistent lock state 6.1.0-rc5-syzkaller-00008-ge01d50cbd6ee #0 Not tainted -------------------------------- inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. syz-executor.4/7818 [HC0[0]:SC0[0]:HE0:SE1] takes: ffffffff8cb76bb8 (sync_timeline_list_lock){?...}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:375 [inline] ffffffff8cb76bb8 (sync_timeline_list_lock){?...}-{2:2}, at: sync_info_debugfs_show+0x2d/0x200 drivers/dma-buf/sync_debug.c:147 {IN-HARDIRQ-W} state was registered at: lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1df/0x630 kernel/locking/lockdep.c:5633 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 sync_timeline_debug_remove+0x25/0x190 drivers/dma-buf/sync_debug.c:31 sync_timeline_free drivers/dma-buf/sw_sync.c:104 [inline] kref_put include/linux/kref.h:65 [inline] sync_timeline_put drivers/dma-buf/sw_sync.c:116 [inline] timeline_fence_release+0x263/0x340 drivers/dma-buf/sw_sync.c:144 dma_fence_release+0x147/0x680 drivers/dma-buf/dma-fence.c:559 kref_put include/linux/kref.h:65 [inline] dma_fence_put include/linux/dma-fence.h:276 [inline] dma_fence_array_release+0x1f6/0x2d0 drivers/dma-buf/dma-fence-array.c:120 dma_fence_release+0x147/0x680 drivers/dma-buf/dma-fence.c:559 kref_put include/linux/kref.h:65 [inline] dma_fence_put include/linux/dma-fence.h:276 [inline] irq_dma_fence_array_work+0xa5/0xd0 drivers/dma-buf/dma-fence-array.c:52 irq_work_single+0x120/0x250 kernel/irq_work.c:211 irq_work_run_list kernel/irq_work.c:242 [inline] irq_work_run_list+0x91/0xc0 kernel/irq_work.c:225 irq_work_run+0x54/0xd0 kernel/irq_work.c:251 __sysvec_irq_work+0xca/0x4d0 arch/x86/kernel/irq_work.c:22 sysvec_irq_work+0x8e/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:675 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:400 [inline] sw_sync_debugfs_release+0x15e/0x230 drivers/dma-buf/sw_sync.c:321 __fput+0x27c/0xa90 fs/file_table.c:320 task_work_run+0x16b/0x270 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xb35/0x2a20 kernel/exit.c:820 do_group_exit+0xd0/0x2a0 kernel/exit.c:950 get_signal+0x21a1/0x2430 kernel/signal.c:2858 arch_do_signal_or_restart+0x82/0x2300 arch/x86/kernel/signal.c:869 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:296 ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:299 irq event stamp: 288 hardirqs last enabled at (287): [<ffffffff81d0a451>] mod_objcg_state+0x591/0xa50 mm/memcontrol.c:3213 hardirqs last disabled at (288): [<ffffffff89922691>] __raw_spin_lock_irq include/linux/spinlock_api_smp.h:117 [inline] hardirqs last disabled at (288): [<ffffffff89922691>] _raw_spin_lock_irq+0x41/0x50 kernel/locking/spinlock.c:170 softirqs last enabled at (0): [<ffffffff8146e349>] copy_process+0x2129/0x7190 kernel/fork.c:2198 softirqs last disabled at (0): [<0000000000000000>] 0x0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sync_timeline_list_lock); <Interrupt> lock(sync_timeline_list_lock); *** DEADLOCK *** 3 locks held by syz-executor.4/7818: #0: ffff8880412b59e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe3/0x100 fs/file.c:1037 #1: ffff888017a97418 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xdf/0x1280 fs/seq_file.c:182 #2: ffffffff8cb76bb8 (sync_timeline_list_lock){?...}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:375 [inline] #2: ffffffff8cb76bb8 (sync_timeline_list_lock){?...}-{2:2}, at: sync_info_debugfs_show+0x2d/0x200 drivers/dma-buf/sync_debug.c:147 stack backtrace: CPU: 0 PID: 7818 Comm: syz-executor.4 Not tainted 6.1.0-rc5-syzkaller-00008-ge01d50cbd6ee #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_usage_bug kernel/locking/lockdep.c:3963 [inline] valid_state kernel/locking/lockdep.c:3975 [inline] mark_lock_irq kernel/locking/lockdep.c:4178 [inline] mark_lock.part.0.cold+0x18/0xd8 kernel/locking/lockdep.c:4634 mark_lock kernel/locking/lockdep.c:4598 [inline] mark_held_locks+0x9f/0xe0 kernel/locking/lockdep.c:4236 __trace_hardirqs_on_caller kernel/locking/lockdep.c:4254 [inline] lockdep_hardirqs_on_prepare kernel/locking/lockdep.c:4321 [inline] lockdep_hardirqs_on_prepare+0x135/0x400 kernel/locking/lockdep.c:4273 trace_hardirqs_on+0x2d/0x160 kernel/trace/trace_preemptirq.c:49 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline] _raw_spin_unlock_irq+0x1f/0x40 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:400 [inline] sync_print_obj drivers/dma-buf/sync_debug.c:118 [inline] sync_info_debugfs_show+0xeb/0x200 drivers/dma-buf/sync_debug.c:153 seq_read_iter+0x4f5/0x1280 fs/seq_file.c:230 seq_read+0x16d/0x210 fs/seq_file.c:162 vfs_read+0x257/0x930 fs/read_write.c:468 ksys_read+0x127/0x250 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f8c5028b639 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f8c4f5ff168 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f8c503ac1f0 RCX: 00007f8c5028b639 RDX: 0000000000002020 RSI: 0000000020001a00 RDI: 000000000000000b RBP: 00007f8c502e6ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8c504cfb1f R14: 00007f8c4f5ff300 R15: 0000000000022000 </TASK> --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller(a)googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

2 years, 1 month

[PATCH v2] drm/gem-shmem: When drm_gem_object_init failed, should release object

by ChunyouTang

when goto err_free, the object had init, so it should be release when fail. Signed-off-by: ChunyouTang <tangchunyou(a)163.com> --- drivers/gpu/drm/drm_gem.c | 19 ++++++++++++++++--- drivers/gpu/drm/drm_gem_shmem_helper.c | 4 +++- include/drm/drm_gem.h | 1 + 3 files changed, 20 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 8b68a3c1e6ab..cba32c46bb05 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -169,6 +169,21 @@ void drm_gem_private_object_init(struct drm_device *dev, } EXPORT_SYMBOL(drm_gem_private_object_init); +/** + * drm_gem_private_object_fini - Finalize a failed drm_gem_object + * @obj: drm_gem_object + * + * Uninitialize an already allocated GEM object when it initialized failed + */ +void drm_gem_private_object_fini(struct drm_gem_object *obj) +{ + WARN_ON(obj->dma_buf); + + dma_resv_fini(&obj->_resv); + drm_gem_lru_remove(obj); +} +EXPORT_SYMBOL(drm_gem_private_object_fini); + /** * drm_gem_object_handle_free - release resources bound to userspace handles * @obj: GEM object to clean up. @@ -930,14 +945,12 @@ drm_gem_release(struct drm_device *dev, struct drm_file *file_private) void drm_gem_object_release(struct drm_gem_object *obj) { - WARN_ON(obj->dma_buf); + drm_gem_private_object_fini(obj); if (obj->filp) fput(obj->filp); - dma_resv_fini(&obj->_resv); drm_gem_free_mmap_offset(obj); - drm_gem_lru_remove(obj); } EXPORT_SYMBOL(drm_gem_object_release); diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index 35138f8a375c..845e3d5d71eb 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -79,8 +79,10 @@ __drm_gem_shmem_create(struct drm_device *dev, size_t size, bool private) } else { ret = drm_gem_object_init(dev, obj, size); } - if (ret) + if (ret) { + drm_gem_private_object_fini(obj) goto err_free; + } ret = drm_gem_create_mmap_offset(obj); if (ret) diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index bd42f25e449c..9b1feb03069d 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -405,6 +405,7 @@ int drm_gem_object_init(struct drm_device *dev, struct drm_gem_object *obj, size_t size); void drm_gem_private_object_init(struct drm_device *dev, struct drm_gem_object *obj, size_t size); +void drm_gem_private_object_fini(struct drm_gem_object *obj); void drm_gem_vm_open(struct vm_area_struct *vma); void drm_gem_vm_close(struct vm_area_struct *vma); int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size, -- 2.25.1

2 years, 1 month

[PATCH v5] udmabuf: add vmap and vunmap methods to udmabuf_ops

by Lukasz Wiecaszek

The reason behind that patch is associated with videobuf2 subsystem (or more genrally with v4l2 framework) and user created dma buffers (udmabuf). In some circumstances when dealing with V4L2_MEMORY_DMABUF buffers videobuf2 subsystem wants to use dma_buf_vmap() method on the attached dma buffer. As udmabuf does not have .vmap operation implemented, such dma_buf_vmap() natually fails. videobuf2_common: __vb2_queue_alloc: allocated 3 buffers, 1 plane(s) each videobuf2_common: __prepare_dmabuf: buffer for plane 0 changed videobuf2_common: __prepare_dmabuf: failed to map dmabuf for plane 0 videobuf2_common: __buf_prepare: buffer preparation failed: -14 The patch itself seems to be strighforward. It adds implementation of .vmap and .vunmap methods to 'struct dma_buf_ops udmabuf_ops'. .vmap method itself uses vm_map_ram() to map pages linearly into the kernel virtual address space. .vunmap removes mapping created earlier by .vmap. All locking and 'vmapping counting' is done in dma_buf.c so it seems to be redundant/unnecessary in .vmap/.vunmap. Reviewed-by: Dmitry Osipenko <dmitry.osipenko(a)collabora.com> Acked-by: Christian König <christian.koenig(a)amd.com> Signed-off-by: Lukasz Wiecaszek <lukasz.wiecaszek(a)gmail.com> --- v1: https://lore.kernel.org/linux-media/202211120352.G7WPASoP-lkp@intel.com/T/#t v2: https://lore.kernel.org/linux-media/20221114052944.GA7264@thinkpad-p72/T/#t v3: https://lore.kernel.org/linux-media/4f92e95f-a0dc-4eac-4c08-0df85de78ae7@co… v4: https://lore.kernel.org/linux-media/970e798d-ea26-5e1e-ace8-7915a866f7c7@co… v4 -> v5: Added Acked-by and Reviewed-by to the commit message v3 -> v4: Removed line/info 'reported by kernel test robot' v2 -> v3: Added .vunmap to 'struct dma_buf_ops udmabuf_ops' v1 -> v2: Patch prepared and tested against 6.1.0-rc2+ drivers/dma-buf/udmabuf.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c index 283816fbd72f..740d6e426ee9 100644 --- a/drivers/dma-buf/udmabuf.c +++ b/drivers/dma-buf/udmabuf.c @@ -13,6 +13,8 @@ #include <linux/slab.h> #include <linux/udmabuf.h> #include <linux/hugetlb.h> +#include <linux/vmalloc.h> +#include <linux/iosys-map.h> static int list_limit = 1024; module_param(list_limit, int, 0644); @@ -60,6 +62,30 @@ static int mmap_udmabuf(struct dma_buf *buf, struct vm_area_struct *vma) return 0; } +static int vmap_udmabuf(struct dma_buf *buf, struct iosys_map *map) +{ + struct udmabuf *ubuf = buf->priv; + void *vaddr; + + dma_resv_assert_held(buf->resv); + + vaddr = vm_map_ram(ubuf->pages, ubuf->pagecount, -1); + if (!vaddr) + return -EINVAL; + + iosys_map_set_vaddr(map, vaddr); + return 0; +} + +static void vunmap_udmabuf(struct dma_buf *buf, struct iosys_map *map) +{ + struct udmabuf *ubuf = buf->priv; + + dma_resv_assert_held(buf->resv); + + vm_unmap_ram(map->vaddr, ubuf->pagecount); +} + static struct sg_table *get_sg_table(struct device *dev, struct dma_buf *buf, enum dma_data_direction direction) { @@ -162,6 +188,8 @@ static const struct dma_buf_ops udmabuf_ops = { .unmap_dma_buf = unmap_udmabuf, .release = release_udmabuf, .mmap = mmap_udmabuf, + .vmap = vmap_udmabuf, + .vunmap = vunmap_udmabuf, .begin_cpu_access = begin_cpu_udmabuf, .end_cpu_access = end_cpu_udmabuf, }; -- 2.25.1

2 years, 1 month

[PATCH v4] udmabuf: add vmap and vunmap methods to udmabuf_ops

by Lukasz Wiecaszek

The reason behind that patch is associated with videobuf2 subsystem (or more genrally with v4l2 framework) and user created dma buffers (udmabuf). In some circumstances when dealing with V4L2_MEMORY_DMABUF buffers videobuf2 subsystem wants to use dma_buf_vmap() method on the attached dma buffer. As udmabuf does not have .vmap operation implemented, such dma_buf_vmap() natually fails. videobuf2_common: __vb2_queue_alloc: allocated 3 buffers, 1 plane(s) each videobuf2_common: __prepare_dmabuf: buffer for plane 0 changed videobuf2_common: __prepare_dmabuf: failed to map dmabuf for plane 0 videobuf2_common: __buf_prepare: buffer preparation failed: -14 The patch itself seems to be strighforward. It adds implementation of .vmap and .vunmap methods to 'struct dma_buf_ops udmabuf_ops'. .vmap method itself uses vm_map_ram() to map pages linearly into the kernel virtual address space. .vunmap removes mapping created earlier by .vmap. All locking and 'vmapping counting' is done in dma_buf.c so it seems to be redundant/unnecessary in .vmap/.vunmap. Signed-off-by: Lukasz Wiecaszek <lukasz.wiecaszek(a)gmail.com> --- v1: https://lore.kernel.org/linux-media/202211120352.G7WPASoP-lkp@intel.com/T/#t v2: https://lore.kernel.org/linux-media/20221114052944.GA7264@thinkpad-p72/T/#t v3: https://lore.kernel.org/linux-media/4f92e95f-a0dc-4eac-4c08-0df85de78ae7@co… v3 -> v4: Removed line/info 'reported by kernel test robot' v2 -> v3: Added .vunmap to 'struct dma_buf_ops udmabuf_ops' v1 -> v2: Patch prepared and tested against 6.1.0-rc2+ drivers/dma-buf/udmabuf.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c index 283816fbd72f..740d6e426ee9 100644 --- a/drivers/dma-buf/udmabuf.c +++ b/drivers/dma-buf/udmabuf.c @@ -13,6 +13,8 @@ #include <linux/slab.h> #include <linux/udmabuf.h> #include <linux/hugetlb.h> +#include <linux/vmalloc.h> +#include <linux/iosys-map.h> static int list_limit = 1024; module_param(list_limit, int, 0644); @@ -60,6 +62,30 @@ static int mmap_udmabuf(struct dma_buf *buf, struct vm_area_struct *vma) return 0; } +static int vmap_udmabuf(struct dma_buf *buf, struct iosys_map *map) +{ + struct udmabuf *ubuf = buf->priv; + void *vaddr; + + dma_resv_assert_held(buf->resv); + + vaddr = vm_map_ram(ubuf->pages, ubuf->pagecount, -1); + if (!vaddr) + return -EINVAL; + + iosys_map_set_vaddr(map, vaddr); + return 0; +} + +static void vunmap_udmabuf(struct dma_buf *buf, struct iosys_map *map) +{ + struct udmabuf *ubuf = buf->priv; + + dma_resv_assert_held(buf->resv); + + vm_unmap_ram(map->vaddr, ubuf->pagecount); +} + static struct sg_table *get_sg_table(struct device *dev, struct dma_buf *buf, enum dma_data_direction direction) { @@ -162,6 +188,8 @@ static const struct dma_buf_ops udmabuf_ops = { .unmap_dma_buf = unmap_udmabuf, .release = release_udmabuf, .mmap = mmap_udmabuf, + .vmap = vmap_udmabuf, + .vunmap = vunmap_udmabuf, .begin_cpu_access = begin_cpu_udmabuf, .end_cpu_access = end_cpu_udmabuf, }; -- 2.25.1

2 years, 1 month

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Linaro-mm-sig November 2022