kernel.git/drivers/gpu/drm/amd/amdkfd/kfd_process.c, branch linux-5.4.y

drm/amdkfd: KFD release_work possible circular locking

2025-06-04T12:32:32Z

[ Upstream commit 1b9366c601039d60546794c63fbb83ce8e53b978 ] If waiting for gpu reset done in KFD release_work, thers is WARNING: possible circular locking dependency detected #2 kfd_create_process kfd_process_mutex flush kfd release work #1 kfd release work wait for amdgpu reset work #0 amdgpu_device_gpu_reset kgd2kfd_pre_reset kfd_process_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock((work_completion)(&p->release_work)); lock((wq_completion)kfd_process_wq); lock((work_completion)(&p->release_work)); lock((wq_completion)amdgpu-reset-dev); To fix this, KFD create process move flush release work outside kfd_process_mutex. Signed-off-by: Philip Yang Reviewed-by: Felix Kuehling Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin

drm/amdkfd: Flush the process wq before creating a kfd_process

2024-06-16T11:28:31Z

[ Upstream commit f5b9053398e70a0c10aa9cb4dd5910ab6bc457c5 ] There is a race condition when re-creating a kfd_process for a process. This has been observed when a process under the debugger executes exec(3). In this scenario: - The process executes exec. - This will eventually release the process's mm, which will cause the kfd_process object associated with the process to be freed (kfd_process_free_notifier decrements the reference count to the kfd_process to 0). This causes kfd_process_ref_release to enqueue kfd_process_wq_release to the kfd_process_wq. - The debugger receives the PTRACE_EVENT_EXEC notification, and tries to re-enable AMDGPU traps (KFD_IOC_DBG_TRAP_ENABLE). - When handling this request, KFD tries to re-create a kfd_process. This eventually calls kfd_create_process and kobject_init_and_add. At this point the call to kobject_init_and_add can fail because the old kfd_process.kobj has not been freed yet by kfd_process_wq_release. This patch proposes to avoid this race by making sure to drain kfd_process_wq before creating a new kfd_process object. This way, we know that any cleanup task is done executing when we reach kobject_init_and_add. Signed-off-by: Lancelot SIX Reviewed-by: Felix Kuehling Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin

drm/amd: fix potential memleak in err branch

2020-06-30T19:37:10Z

commit b5b78a6c8d8cb9c307bc6b16a754603424459d6e upstream. The function kobject_init_and_add alloc memory like: kobject_init_and_add->kobject_add_varg->kobject_set_name_vargs ->kvasprintf_const->kstrdup_const->kstrdup->kmalloc_track_caller ->kmalloc_slab, in err branch this memory not free. If use kmemleak, this path maybe catched. These changes are to add kobject_put in kobject_init_and_add failed branch, fix potential memleak. Signed-off-by: Bernard Zhao Reviewed-by: Felix Kuehling Signed-off-by: Felix Kuehling Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

2019-09-21T17:07:42Z

Pull hmm updates from Jason Gunthorpe: "This is more cleanup and consolidation of the hmm APIs and the very strongly related mmu_notifier interfaces. Many places across the tree using these interfaces are touched in the process. Beyond that a cleanup to the page walker API and a few memremap related changes round out the series: - General improvement of hmm_range_fault() and related APIs, more documentation, bug fixes from testing, API simplification & consolidation, and unused API removal - Simplify the hmm related kconfigs to HMM_MIRROR and DEVICE_PRIVATE, and make them internal kconfig selects - Hoist a lot of code related to mmu notifier attachment out of drivers by using a refcount get/put attachment idiom and remove the convoluted mmu_notifier_unregister_no_release() and related APIs. - General API improvement for the migrate_vma API and revision of its only user in nouveau - Annotate mmu_notifiers with lockdep and sleeping region debugging Two series unrelated to HMM or mmu_notifiers came along due to dependencies: - Allow pagemap's memremap_pages family of APIs to work without providing a struct device - Make walk_page_range() and related use a constant structure for function pointers" * tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (75 commits) libnvdimm: Enable unit test infrastructure compile checks mm, notifier: Catch sleeping/blocking for !blockable kernel.h: Add non_block_start/end() drm/radeon: guard against calling an unpaired radeon_mn_unregister() csky: add missing brackets in a macro for tlb.h pagewalk: use lockdep_assert_held for locking validation pagewalk: separate function pointers from iterator data mm: split out a new pagewalk.h header from mm.h mm/mmu_notifiers: annotate with might_sleep() mm/mmu_notifiers: prime lockdep mm/mmu_notifiers: add a lockdep map for invalidate_range_start/end mm/mmu_notifiers: remove the __mmu_notifier_invalidate_range_start/end exports mm/hmm: hmm_range_fault() infinite loop mm/hmm: hmm_range_fault() NULL pointer bug mm/hmm: fix hmm_range_fault()'s handling of swapped out pages mm/mmu_notifiers: remove unregister_no_release RDMA/odp: remove ib_ucontext from ib_umem RDMA/odp: use mmu_notifier_get/put for 'struct ib_ucontext_per_mm' RDMA/mlx5: Use odp instead of mr->umem in pagefault_mr RDMA/mlx5: Use ib_umem_start instead of umem.address ...

drm/amdkfd: remove set but not used variable 'pdd'

2019-08-22T03:19:00Z

Fixes gcc '-Wunused-but-set-variable' warning: drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_process.c: In function restore_process_worker: drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_process.c:949:29: warning: variable pdd set but not used [-Wunused-but-set-variable] It is not used since commit 5b87245faf57 ("drm/amdkfd: Simplify kfd2kgd interface") Reported-by: Hulk Robot Signed-off-by: YueHaibing Signed-off-by: Alex Deucher

drm/amdkfd: use mmu_notifier_put

2019-08-20T12:35:02Z

The sequence of mmu_notifier_unregister_no_release(), mmu_notifier_call_srcu() is identical to mmu_notifier_put() with the free_notifier callback. As this is the last user of those APIs, converting it means we can drop them. Link: https://lore.kernel.org/r/20190806231548.25242-11-jgg@ziepe.ca Reviewed-by: Felix Kuehling Signed-off-by: Jason Gunthorpe

drm/amdkfd: fix a use after free race with mmu_notifer unregister

2019-08-20T12:35:02Z

When using mmu_notifer_unregister_no_release() the caller must ensure there is a SRCU synchronize before the mn memory is freed, otherwise use after free races are possible, for instance: CPU0 CPU1 invalidate_range_start hlist_for_each_entry_rcu(..) mmu_notifier_unregister_no_release(&p->mn) kfree(mn) if (mn->ops->invalidate_range_end) The error unwind in amdkfd misses the SRCU synchronization. amdkfd keeps the kfd_process around until the mm is released, so split the flow to fully initialize the kfd_process and register it for find_process, and with the notifier. Past this point the kfd_process does not need to be cleaned up as it is fully ready. The final failable step does a vm_mmap() and does not seem to impact the kfd_process global state. Since it also cannot be undone (and already has problems with undo if it internally fails), it has to be last. This way we don't have to try to unwind the mmu_notifier_register() and avoid the problem with the SRCU. Along the way this also fixes various other error unwind bugs in the flow. Fixes: 45102048f77e ("amdkfd: Add process queue manager module") Link: https://lore.kernel.org/r/20190806231548.25242-10-jgg@ziepe.ca Reviewed-by: Felix Kuehling Signed-off-by: Jason Gunthorpe

drm/amdkfd: Fill amdgpu_task_info for KFD VMs

2019-08-15T15:58:21Z

The amdgpu_task_info will be used when printing VM page fault for KFD processes. Signed-off-by: Yong Zhao Acked-by: Christian König Reviewed-by: Harish Kasiviswanathan Signed-off-by: Alex Deucher

drm/amdkfd: Add navi10 support to amdkfd. (v3)

2019-06-21T23:59:24Z

KFD (kernel fusion driver) is the kernel driver for the compute backend for usermode compute stack. v2: squash in updates (Alex) v3: squash in rebase fixes (Alex) Signed-off-by: Oak Zeng Signed-off-by: Philip Cox Acked-by: Alex Deucher Signed-off-by: Hawking Zhang Signed-off-by: Alex Deucher

drm/amdkfd: Add procfs-style information for KFD processes

2019-06-20T16:34:00Z

Add a folder structure to /sys/class/kfd/kfd/ called proc which contains subfolders, each representing an active KFD process' PID, containing 1 file: pasid. Signed-off-by: Kent Russell Reviewed-by: Felix Kuehling Acked-by: Christian König Signed-off-by: Alex Deucher