[PATCH RFC POC 27/50] drm/amdkfd: stop collecting CRIU dma-buf descriptors for a final install
From: Christian Brauner <brauner@kernel.org>
Date: 2026-09-15 11:34:48
Also in:
bpf, dri-devel, io-uring, kexec, kvm, linux-alpha, linux-arm-kernel, linux-arm-msm, linux-fsdevel, linux-gpio, linux-hyperv, linux-m68k, linux-mips, linux-mm, linux-sh, linux-um, lkml, netdev, sparclinux, virtualization
Subsystem:
amd kfd, drm drivers, radeon and amdgpu drm drivers, the rest · Maintainers:
Felix Kuehling, David Airlie, Simona Vetter, Alex Deucher, Christian König, Linus Torvalds
Rely on the fd exit path machinery. Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org> --- drivers/gpu/drm/amd/amdkfd/kfd_chardev.c | 67 +++++++------------------------- 1 file changed, 13 insertions(+), 54 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
index 7fcfc150a7fc..158abe7e3da6 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c@@ -1988,11 +1988,10 @@ static uint32_t get_process_num_bos(struct kfd_process *p) return num_of_bos; } -static int criu_get_prime_handle(struct kgd_mem *mem, - int flags, u32 *shared_fd, - struct file **file) +static int criu_get_prime_handle(struct kgd_mem *mem, int flags, u32 *shared_fd) { struct dma_buf *dmabuf; + const struct fd_slot *fd; int ret; ret = amdgpu_amdkfd_gpuvm_export_dmabuf(mem, &dmabuf);
@@ -2001,38 +2000,17 @@ static int criu_get_prime_handle(struct kgd_mem *mem, return ret; } - ret = get_unused_fd_flags(flags); - if (ret < 0) { + fd = fd_prepare(flags); + if (IS_ERR(fd)) { + ret = PTR_ERR(fd); pr_err("dmabuf create fd failed, ret:%d\n", ret); - goto out_free_dmabuf; + dma_buf_put(dmabuf); + return ret; } - *shared_fd = ret; - *file = dmabuf->file; + /* Installed or dropped with the ioctl's result, nothing to put back. */ + *shared_fd = fd_stage(fd, dmabuf->file); return 0; - -out_free_dmabuf: - dma_buf_put(dmabuf); - return ret; -} - -static void commit_files(struct file **files, - struct kfd_criu_bo_bucket *bo_buckets, - unsigned int count, - int err) -{ - while (count--) { - struct file *file = files[count]; - - if (!file) - continue; - if (err) { - fput(file); - put_unused_fd(bo_buckets[count].dmabuf_fd); - } else { - fd_install(bo_buckets[count].dmabuf_fd, file); - } - } } static int criu_checkpoint_bos(struct kfd_process *p,
@@ -2043,7 +2021,6 @@ static int criu_checkpoint_bos(struct kfd_process *p, { struct kfd_criu_bo_bucket *bo_buckets; struct kfd_criu_bo_priv_data *bo_privs; - struct file **files = NULL; int ret = 0, pdd_index, bo_index = 0, id; void *mem;
@@ -2057,12 +2034,6 @@ static int criu_checkpoint_bos(struct kfd_process *p, goto exit; } - files = kvcalloc(num_bos, sizeof(struct file *), GFP_KERNEL); - if (!files) { - ret = -ENOMEM; - goto exit; - } - for (pdd_index = 0; pdd_index < p->n_pdds; pdd_index++) { struct kfd_process_device *pdd = p->pdds[pdd_index]; struct amdgpu_bo *dumper_bo;
@@ -2105,7 +2076,7 @@ static int criu_checkpoint_bos(struct kfd_process *p, ret = criu_get_prime_handle(kgd_mem, bo_bucket->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE ? DRM_RDWR : 0, - &bo_bucket->dmabuf_fd, &files[bo_index]); + &bo_bucket->dmabuf_fd); if (ret) goto exit; } else {
@@ -2156,8 +2127,6 @@ static int criu_checkpoint_bos(struct kfd_process *p, *priv_offset += num_bos * sizeof(*bo_privs); exit: - commit_files(files, bo_buckets, bo_index, ret); - kvfree(files); kvfree(bo_buckets); kvfree(bo_privs); return ret;
@@ -2504,8 +2473,7 @@ static int criu_restore_memory_of_gpu(struct kfd_process_device *pdd, static int criu_restore_bo(struct kfd_process *p, struct kfd_criu_bo_bucket *bo_bucket, - struct kfd_criu_bo_priv_data *bo_priv, - struct file **file) + struct kfd_criu_bo_priv_data *bo_priv) { struct kfd_process_device *pdd; struct kgd_mem *kgd_mem;
@@ -2557,7 +2525,7 @@ static int criu_restore_bo(struct kfd_process *p, if (bo_bucket->alloc_flags & (KFD_IOC_ALLOC_MEM_FLAGS_VRAM | KFD_IOC_ALLOC_MEM_FLAGS_GTT)) { ret = criu_get_prime_handle(kgd_mem, DRM_RDWR, - &bo_bucket->dmabuf_fd, file); + &bo_bucket->dmabuf_fd); if (ret) return ret; } else {
@@ -2574,7 +2542,6 @@ static int criu_restore_bos(struct kfd_process *p, { struct kfd_criu_bo_bucket *bo_buckets = NULL; struct kfd_criu_bo_priv_data *bo_privs = NULL; - struct file **files = NULL; int ret = 0; uint32_t i = 0;
@@ -2588,12 +2555,6 @@ static int criu_restore_bos(struct kfd_process *p, if (!bo_buckets) return -ENOMEM; - files = kvcalloc(args->num_bos, sizeof(struct file *), GFP_KERNEL); - if (!files) { - ret = -ENOMEM; - goto exit; - } - ret = copy_from_user(bo_buckets, (void __user *)args->bos, args->num_bos * sizeof(*bo_buckets)); if (ret) {
@@ -2619,7 +2580,7 @@ static int criu_restore_bos(struct kfd_process *p, /* Create and map new BOs */ for (; i < args->num_bos; i++) { - ret = criu_restore_bo(p, &bo_buckets[i], &bo_privs[i], &files[i]); + ret = criu_restore_bo(p, &bo_buckets[i], &bo_privs[i]); if (ret) { pr_debug("Failed to restore BO[%d] ret%d\n", i, ret); goto exit;
@@ -2634,8 +2595,6 @@ static int criu_restore_bos(struct kfd_process *p, ret = -EFAULT; exit: - commit_files(files, bo_buckets, i, ret); - kvfree(files); kvfree(bo_buckets); kvfree(bo_privs); return ret;
--
2.53.0