linux/kernel/module/kdb.c
Song Liu ac3b432839 module: replace module_layout with module_memory
module_layout manages different types of memory (text, data, rodata, etc.)
in one allocation, which is problematic for some reasons:

1. It is hard to enable CONFIG_STRICT_MODULE_RWX.
2. It is hard to use huge pages in modules (and not break strict rwx).
3. Many archs uses module_layout for arch-specific data, but it is not
   obvious how these data are used (are they RO, RX, or RW?)

Improve the scenario by replacing 2 (or 3) module_layout per module with
up to 7 module_memory per module:

        MOD_TEXT,
        MOD_DATA,
        MOD_RODATA,
        MOD_RO_AFTER_INIT,
        MOD_INIT_TEXT,
        MOD_INIT_DATA,
        MOD_INIT_RODATA,

and allocating them separately. This adds slightly more entries to
mod_tree (from up to 3 entries per module, to up to 7 entries per
module). However, this at most adds a small constant overhead to
__module_address(), which is expected to be fast.

Various archs use module_layout for different data. These data are put
into different module_memory based on their location in module_layout.
IOW, data that used to go with text is allocated with MOD_MEM_TYPE_TEXT;
data that used to go with data is allocated with MOD_MEM_TYPE_DATA, etc.

module_memory simplifies quite some of the module code. For example,
ARCH_WANTS_MODULES_DATA_IN_VMALLOC is a lot cleaner, as it just uses a
different allocator for the data. kernel/module/strict_rwx.c is also
much cleaner with module_memory.

Signed-off-by: Song Liu <song@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-09 12:55:15 -08:00

64 lines
1.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Module kdb support
*
* Copyright (C) 2010 Jason Wessel
*/
#include <linux/module.h>
#include <linux/kdb.h>
#include "internal.h"
/*
* kdb_lsmod - This function implements the 'lsmod' command. Lists
* currently loaded kernel modules.
* Mostly taken from userland lsmod.
*/
int kdb_lsmod(int argc, const char **argv)
{
struct module *mod;
if (argc != 0)
return KDB_ARGCOUNT;
kdb_printf("Module Size modstruct Used by\n");
list_for_each_entry(mod, &modules, list) {
if (mod->state == MODULE_STATE_UNFORMED)
continue;
kdb_printf("%-20s%8u", mod->name, mod->mem[MOD_TEXT].size);
kdb_printf("/%8u", mod->mem[MOD_RODATA].size);
kdb_printf("/%8u", mod->mem[MOD_RO_AFTER_INIT].size);
kdb_printf("/%8u", mod->mem[MOD_DATA].size);
kdb_printf(" 0x%px ", (void *)mod);
#ifdef CONFIG_MODULE_UNLOAD
kdb_printf("%4d ", module_refcount(mod));
#endif
if (mod->state == MODULE_STATE_GOING)
kdb_printf(" (Unloading)");
else if (mod->state == MODULE_STATE_COMING)
kdb_printf(" (Loading)");
else
kdb_printf(" (Live)");
kdb_printf(" 0x%px", mod->mem[MOD_TEXT].base);
kdb_printf("/0x%px", mod->mem[MOD_RODATA].base);
kdb_printf("/0x%px", mod->mem[MOD_RO_AFTER_INIT].base);
kdb_printf("/0x%px", mod->mem[MOD_DATA].base);
#ifdef CONFIG_MODULE_UNLOAD
{
struct module_use *use;
kdb_printf(" [ ");
list_for_each_entry(use, &mod->source_list,
source_list)
kdb_printf("%s ", use->target->name);
kdb_printf("]\n");
}
#endif
}
return 0;
}