From 27600805e62f800bacf990354632eae4e487d34c Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Thu, 3 Sep 2026 10:43:25 -0500 Subject: x86/amd_node: Fix PCI device reference counting in amd_smn_init() The local "root" pointer is a temporary variable used during the device search. Therefore, refcount related to the search iterators should be cleaned up after the search is complete. Use the __free() cleanup macro to ensure the refcount is decremented when the temporary pointer goes out of scope. Additionally, increment the refcount when caching a root pointer. This ensures the in-use refcount is separate from the temporary search refcounting. Finally, drop the redundant "root = NULL" before the second search loop. The pci_get_class() iterator always decrements the refcount of its "from" argument, so the first loop can only fall through with "root" already NULL. Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching") Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com Reported-by: Sashiko Assisted-by: LLM Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Mario Limonciello (AMD) Cc: Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com --- io_uring/filetable.c | 158 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 158 insertions(+) create mode 100644 io_uring/filetable.c (limited to 'io_uring/filetable.c') diff --git a/io_uring/filetable.c b/io_uring/filetable.c new file mode 100644 index 000000000..cb1838c9f --- /dev/null +++ b/io_uring/filetable.c @@ -0,0 +1,158 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include + +#include + +#include "io_uring.h" +#include "rsrc.h" +#include "filetable.h" + +static int io_file_bitmap_get(struct io_ring_ctx *ctx) +{ + struct io_file_table *table = &ctx->file_table; + unsigned long nr = ctx->file_alloc_end; + int ret; + + if (!table->bitmap) + return -ENFILE; + + if (table->alloc_hint < ctx->file_alloc_start || + table->alloc_hint >= ctx->file_alloc_end) + table->alloc_hint = ctx->file_alloc_start; + + do { + ret = find_next_zero_bit(table->bitmap, nr, table->alloc_hint); + if (ret != nr) + return ret; + + if (table->alloc_hint == ctx->file_alloc_start) + break; + nr = table->alloc_hint; + table->alloc_hint = ctx->file_alloc_start; + } while (1); + + return -ENFILE; +} + +bool io_alloc_file_tables(struct io_ring_ctx *ctx, struct io_file_table *table, + unsigned nr_files) +{ + if (io_rsrc_data_alloc(&table->data, nr_files)) + return false; + table->bitmap = bitmap_zalloc(nr_files, GFP_KERNEL_ACCOUNT); + if (table->bitmap) + return true; + io_rsrc_data_free(ctx, &table->data); + return false; +} + +void io_free_file_tables(struct io_ring_ctx *ctx, struct io_file_table *table) +{ + io_rsrc_data_free(ctx, &table->data); + bitmap_free(table->bitmap); + table->bitmap = NULL; +} + +static int io_install_fixed_file(struct io_ring_ctx *ctx, struct file *file, + u32 slot_index) + __must_hold(&ctx->uring_lock) +{ + struct io_rsrc_node *node; + + if (io_is_uring_fops(file)) + return -EBADF; + if (!ctx->file_table.data.nr) + return -ENXIO; + if (slot_index >= ctx->file_table.data.nr) + return -EINVAL; + + node = io_rsrc_node_alloc(ctx, IORING_RSRC_FILE); + if (!node) + return -ENOMEM; + + if (!io_reset_rsrc_node(ctx, &ctx->file_table.data, slot_index)) + io_file_bitmap_set(&ctx->file_table, slot_index); + + ctx->file_table.data.nodes[slot_index] = node; + io_fixed_file_set(node, file); + return 0; +} + +int __io_fixed_fd_install(struct io_ring_ctx *ctx, struct file *file, + unsigned int file_slot) +{ + bool alloc_slot = file_slot == IORING_FILE_INDEX_ALLOC; + int ret; + + if (alloc_slot) { + ret = io_file_bitmap_get(ctx); + if (unlikely(ret < 0)) + return ret; + file_slot = ret; + } else { + file_slot--; + } + + ret = io_install_fixed_file(ctx, file, file_slot); + if (!ret && alloc_slot) + ret = file_slot; + return ret; +} +/* + * Note when io_fixed_fd_install() returns error value, it will ensure + * fput() is called correspondingly. + */ +int io_fixed_fd_install(struct io_kiocb *req, unsigned int issue_flags, + struct file *file, unsigned int file_slot) +{ + struct io_ring_ctx *ctx = req->ctx; + int ret; + + io_ring_submit_lock(ctx, issue_flags); + ret = __io_fixed_fd_install(ctx, file, file_slot); + io_ring_submit_unlock(ctx, issue_flags); + + if (unlikely(ret < 0)) + fput(file); + return ret; +} + +int io_fixed_fd_remove(struct io_ring_ctx *ctx, unsigned int offset) +{ + struct io_rsrc_node *node; + + if (unlikely(!ctx->file_table.data.nr)) + return -ENXIO; + if (offset >= ctx->file_table.data.nr) + return -EINVAL; + + node = io_rsrc_node_lookup(&ctx->file_table.data, offset); + if (!node) + return -EBADF; + io_reset_rsrc_node(ctx, &ctx->file_table.data, offset); + io_file_bitmap_clear(&ctx->file_table, offset); + return 0; +} + +int io_register_file_alloc_range(struct io_ring_ctx *ctx, + struct io_uring_file_index_range __user *arg) +{ + struct io_uring_file_index_range range; + u32 end; + + if (copy_from_user(&range, arg, sizeof(range))) + return -EFAULT; + if (check_add_overflow(range.off, range.len, &end)) + return -EOVERFLOW; + if (range.resv || end > ctx->file_table.data.nr) + return -EINVAL; + + io_file_table_set_alloc_range(ctx, range.off, range.len); + return 0; +} -- cgit v1.3.1