From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- fs/jffs2/malloc.c | 299 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 299 insertions(+) create mode 100644 fs/jffs2/malloc.c (limited to 'fs/jffs2/malloc.c') diff --git a/fs/jffs2/malloc.c b/fs/jffs2/malloc.c new file mode 100644 index 000000000..411de8b36 --- /dev/null +++ b/fs/jffs2/malloc.c @@ -0,0 +1,299 @@ +/* + * JFFS2 -- Journalling Flash File System, Version 2. + * + * Copyright © 2001-2007 Red Hat, Inc. + * + * Created by David Woodhouse + * + * For licensing information, see the file 'LICENCE' in this directory. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include "nodelist.h" + +/* These are initialised to NULL in the kernel startup code. + If you're porting to other operating systems, beware */ +static struct kmem_cache *full_dnode_slab; +static struct kmem_cache *raw_dirent_slab; +static struct kmem_cache *raw_inode_slab; +static struct kmem_cache *tmp_dnode_info_slab; +static struct kmem_cache *raw_node_ref_slab; +static struct kmem_cache *node_frag_slab; +static struct kmem_cache *inode_cache_slab; +#ifdef CONFIG_JFFS2_FS_XATTR +static struct kmem_cache *xattr_datum_cache; +static struct kmem_cache *xattr_ref_cache; +#endif + +int __init jffs2_create_slab_caches(void) +{ + full_dnode_slab = KMEM_CACHE(jffs2_full_dnode, 0); + if (!full_dnode_slab) + goto err; + + raw_dirent_slab = KMEM_CACHE(jffs2_raw_dirent, SLAB_HWCACHE_ALIGN); + if (!raw_dirent_slab) + goto err; + + raw_inode_slab = KMEM_CACHE(jffs2_raw_inode, SLAB_HWCACHE_ALIGN); + if (!raw_inode_slab) + goto err; + + tmp_dnode_info_slab = KMEM_CACHE(jffs2_tmp_dnode_info, 0); + if (!tmp_dnode_info_slab) + goto err; + + raw_node_ref_slab = kmem_cache_create("jffs2_refblock", + sizeof(struct jffs2_raw_node_ref) * (REFS_PER_BLOCK + 1), + 0, 0, NULL); + if (!raw_node_ref_slab) + goto err; + + node_frag_slab = KMEM_CACHE(jffs2_node_frag, 0); + if (!node_frag_slab) + goto err; + + inode_cache_slab = KMEM_CACHE(jffs2_inode_cache, 0); + if (!inode_cache_slab) + goto err; + +#ifdef CONFIG_JFFS2_FS_XATTR + xattr_datum_cache = KMEM_CACHE(jffs2_xattr_datum, 0); + if (!xattr_datum_cache) + goto err; + + xattr_ref_cache = KMEM_CACHE(jffs2_xattr_ref, 0); + if (!xattr_ref_cache) + goto err; +#endif + + return 0; + err: + jffs2_destroy_slab_caches(); + return -ENOMEM; +} + +void jffs2_destroy_slab_caches(void) +{ + kmem_cache_destroy(full_dnode_slab); + kmem_cache_destroy(raw_dirent_slab); + kmem_cache_destroy(raw_inode_slab); + kmem_cache_destroy(tmp_dnode_info_slab); + kmem_cache_destroy(raw_node_ref_slab); + kmem_cache_destroy(node_frag_slab); + kmem_cache_destroy(inode_cache_slab); +#ifdef CONFIG_JFFS2_FS_XATTR + kmem_cache_destroy(xattr_datum_cache); + kmem_cache_destroy(xattr_ref_cache); +#endif +} + +struct jffs2_full_dirent *jffs2_alloc_full_dirent(int namesize) +{ + struct jffs2_full_dirent *ret; + ret = kmalloc(sizeof(struct jffs2_full_dirent) + namesize, GFP_KERNEL); + dbg_memalloc("%p\n", ret); + return ret; +} + +void jffs2_free_full_dirent(struct jffs2_full_dirent *x) +{ + dbg_memalloc("%p\n", x); + kfree(x); +} + +struct jffs2_full_dnode *jffs2_alloc_full_dnode(void) +{ + struct jffs2_full_dnode *ret; + ret = kmem_cache_alloc(full_dnode_slab, GFP_KERNEL); + dbg_memalloc("%p\n", ret); + return ret; +} + +void jffs2_free_full_dnode(struct jffs2_full_dnode *x) +{ + dbg_memalloc("%p\n", x); + kmem_cache_free(full_dnode_slab, x); +} + +struct jffs2_raw_dirent *jffs2_alloc_raw_dirent(void) +{ + struct jffs2_raw_dirent *ret; + ret = kmem_cache_alloc(raw_dirent_slab, GFP_KERNEL); + dbg_memalloc("%p\n", ret); + return ret; +} + +void jffs2_free_raw_dirent(struct jffs2_raw_dirent *x) +{ + dbg_memalloc("%p\n", x); + kmem_cache_free(raw_dirent_slab, x); +} + +struct jffs2_raw_inode *jffs2_alloc_raw_inode(void) +{ + struct jffs2_raw_inode *ret; + ret = kmem_cache_alloc(raw_inode_slab, GFP_KERNEL); + dbg_memalloc("%p\n", ret); + return ret; +} + +void jffs2_free_raw_inode(struct jffs2_raw_inode *x) +{ + dbg_memalloc("%p\n", x); + kmem_cache_free(raw_inode_slab, x); +} + +struct jffs2_tmp_dnode_info *jffs2_alloc_tmp_dnode_info(void) +{ + struct jffs2_tmp_dnode_info *ret; + ret = kmem_cache_alloc(tmp_dnode_info_slab, GFP_KERNEL); + dbg_memalloc("%p\n", + ret); + return ret; +} + +void jffs2_free_tmp_dnode_info(struct jffs2_tmp_dnode_info *x) +{ + dbg_memalloc("%p\n", x); + kmem_cache_free(tmp_dnode_info_slab, x); +} + +static struct jffs2_raw_node_ref *jffs2_alloc_refblock(void) +{ + struct jffs2_raw_node_ref *ret; + + ret = kmem_cache_alloc(raw_node_ref_slab, GFP_KERNEL); + if (ret) { + int i = 0; + for (i=0; i < REFS_PER_BLOCK; i++) { + ret[i].flash_offset = REF_EMPTY_NODE; + ret[i].next_in_ino = NULL; + } + ret[i].flash_offset = REF_LINK_NODE; + ret[i].next_in_ino = NULL; + } + return ret; +} + +int jffs2_prealloc_raw_node_refs(struct jffs2_sb_info *c, + struct jffs2_eraseblock *jeb, int nr) +{ + struct jffs2_raw_node_ref **p, *ref; + int i = nr; + + dbg_memalloc("%d\n", nr); + + p = &jeb->last_node; + ref = *p; + + dbg_memalloc("Reserving %d refs for block @0x%08x\n", nr, jeb->offset); + + /* If jeb->last_node is really a valid node then skip over it */ + if (ref && ref->flash_offset != REF_EMPTY_NODE) + ref++; + + while (i) { + if (!ref) { + dbg_memalloc("Allocating new refblock linked from %p\n", p); + ref = *p = jffs2_alloc_refblock(); + if (!ref) + return -ENOMEM; + } + if (ref->flash_offset == REF_LINK_NODE) { + p = &ref->next_in_ino; + ref = *p; + continue; + } + i--; + ref++; + } + jeb->allocated_refs = nr; + + dbg_memalloc("Reserved %d refs for block @0x%08x, last_node is %p (%08x,%p)\n", + nr, jeb->offset, jeb->last_node, jeb->last_node->flash_offset, + jeb->last_node->next_in_ino); + + return 0; +} + +void jffs2_free_refblock(struct jffs2_raw_node_ref *x) +{ + dbg_memalloc("%p\n", x); + kmem_cache_free(raw_node_ref_slab, x); +} + +struct jffs2_node_frag *jffs2_alloc_node_frag(void) +{ + struct jffs2_node_frag *ret; + ret = kmem_cache_alloc(node_frag_slab, GFP_KERNEL); + dbg_memalloc("%p\n", ret); + return ret; +} + +void jffs2_free_node_frag(struct jffs2_node_frag *x) +{ + dbg_memalloc("%p\n", x); + kmem_cache_free(node_frag_slab, x); +} + +struct jffs2_inode_cache *jffs2_alloc_inode_cache(void) +{ + struct jffs2_inode_cache *ret; + ret = kmem_cache_alloc(inode_cache_slab, GFP_KERNEL); + dbg_memalloc("%p\n", ret); + return ret; +} + +void jffs2_free_inode_cache(struct jffs2_inode_cache *x) +{ + dbg_memalloc("%p\n", x); + kmem_cache_free(inode_cache_slab, x); +} + +#ifdef CONFIG_JFFS2_FS_XATTR +struct jffs2_xattr_datum *jffs2_alloc_xattr_datum(void) +{ + struct jffs2_xattr_datum *xd; + xd = kmem_cache_zalloc(xattr_datum_cache, GFP_KERNEL); + dbg_memalloc("%p\n", xd); + if (!xd) + return NULL; + + xd->class = RAWNODE_CLASS_XATTR_DATUM; + xd->node = (void *)xd; + INIT_LIST_HEAD(&xd->xindex); + return xd; +} + +void jffs2_free_xattr_datum(struct jffs2_xattr_datum *xd) +{ + dbg_memalloc("%p\n", xd); + kmem_cache_free(xattr_datum_cache, xd); +} + +struct jffs2_xattr_ref *jffs2_alloc_xattr_ref(void) +{ + struct jffs2_xattr_ref *ref; + ref = kmem_cache_zalloc(xattr_ref_cache, GFP_KERNEL); + dbg_memalloc("%p\n", ref); + if (!ref) + return NULL; + + ref->class = RAWNODE_CLASS_XATTR_REF; + ref->node = (void *)ref; + return ref; +} + +void jffs2_free_xattr_ref(struct jffs2_xattr_ref *ref) +{ + dbg_memalloc("%p\n", ref); + kmem_cache_free(xattr_ref_cache, ref); +} +#endif -- cgit v1.3.1