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author | Ananth N Mavinakayanahalli <ananth@in.ibm.com> | 2006-10-02 02:17:30 -0700 |
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committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-10-02 07:57:16 -0700 |
commit | 3a872d89baae821a0f6e2c1055d4b47650661137 (patch) | |
tree | 5ac6aa55e04960e02f25ff5079078f975957b1b3 /kernel | |
parent | 782237a2418e2561a87c86a4832726931adce737 (diff) | |
download | kernel_samsung_tuna-3a872d89baae821a0f6e2c1055d4b47650661137.zip kernel_samsung_tuna-3a872d89baae821a0f6e2c1055d4b47650661137.tar.gz kernel_samsung_tuna-3a872d89baae821a0f6e2c1055d4b47650661137.tar.bz2 |
[PATCH] Kprobes: Make kprobe modules more portable
In an effort to make kprobe modules more portable, here is a patch that:
o Introduces the "symbol_name" field to struct kprobe.
The symbol->address resolution now happens in the kernel in an
architecture agnostic manner. 64-bit powerpc users no longer have
to specify the ".symbols"
o Introduces the "offset" field to struct kprobe to allow a user to
specify an offset into a symbol.
o The legacy mechanism of specifying the kprobe.addr is still supported.
However, if both the kprobe.addr and kprobe.symbol_name are specified,
probe registration fails with an -EINVAL.
o The symbol resolution code uses kallsyms_lookup_name(). So
CONFIG_KPROBES now depends on CONFIG_KALLSYMS
o Apparantly kprobe modules were the only legitimate out-of-tree user of
the kallsyms_lookup_name() EXPORT. Now that the symbol resolution
happens in-kernel, remove the EXPORT as suggested by Christoph Hellwig
o Modify tcp_probe.c that uses the kprobe interface so as to make it
work on multiple platforms (in its earlier form, the code wouldn't
work, say, on powerpc)
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/kallsyms.c | 1 | ||||
-rw-r--r-- | kernel/kprobes.c | 26 |
2 files changed, 26 insertions, 1 deletions
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index ab16a5a..342bca6 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -154,7 +154,6 @@ unsigned long kallsyms_lookup_name(const char *name) } return module_kallsyms_lookup_name(name); } -EXPORT_SYMBOL_GPL(kallsyms_lookup_name); /* * Lookup an address diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 3f57dfd..f66b8e6 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -37,6 +37,7 @@ #include <linux/slab.h> #include <linux/module.h> #include <linux/moduleloader.h> +#include <linux/kallsyms.h> #include <asm-generic/sections.h> #include <asm/cacheflush.h> #include <asm/errno.h> @@ -45,6 +46,16 @@ #define KPROBE_HASH_BITS 6 #define KPROBE_TABLE_SIZE (1 << KPROBE_HASH_BITS) + +/* + * Some oddball architectures like 64bit powerpc have function descriptors + * so this must be overridable. + */ +#ifndef kprobe_lookup_name +#define kprobe_lookup_name(name, addr) \ + addr = ((kprobe_opcode_t *)(kallsyms_lookup_name(name))) +#endif + static struct hlist_head kprobe_table[KPROBE_TABLE_SIZE]; static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE]; static atomic_t kprobe_count; @@ -447,6 +458,21 @@ static int __kprobes __register_kprobe(struct kprobe *p, struct kprobe *old_p; struct module *probed_mod; + /* + * If we have a symbol_name argument look it up, + * and add it to the address. That way the addr + * field can either be global or relative to a symbol. + */ + if (p->symbol_name) { + if (p->addr) + return -EINVAL; + kprobe_lookup_name(p->symbol_name, p->addr); + } + + if (!p->addr) + return -EINVAL; + p->addr = (kprobe_opcode_t *)(((char *)p->addr)+ p->offset); + if ((!kernel_text_address((unsigned long) p->addr)) || in_kprobes_functions((unsigned long) p->addr)) return -EINVAL; |