mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-06 05:26:40 +07:00
2553b67a1f
The traceoff_on_warning option doesn't have any effect on s390, powerpc, arm64, parisc, and sh because there are two different types of WARN implementations: 1) The above mentioned architectures treat WARN() as a special case of a BUG() exception. They handle warnings in report_bug() in lib/bug.c. 2) All other architectures just call warn_slowpath_*() directly. Their warnings are handled in warn_slowpath_common() in kernel/panic.c. Support traceoff_on_warning on all architectures and prevent any future divergence by using a single common function to emit the warning. Also remove the '()' from '%pS()', because the parentheses look funky: [ 45.607629] WARNING: at /root/warn_mod/warn_mod.c:17 .init_dummy+0x20/0x40 [warn_mod]() Reported-by: Chunyu Hu <chuhu@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Tested-by: Prarit Bhargava <prarit@redhat.com> Acked-by: Prarit Bhargava <prarit@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
185 lines
4.7 KiB
C
185 lines
4.7 KiB
C
/*
|
|
Generic support for BUG()
|
|
|
|
This respects the following config options:
|
|
|
|
CONFIG_BUG - emit BUG traps. Nothing happens without this.
|
|
CONFIG_GENERIC_BUG - enable this code.
|
|
CONFIG_GENERIC_BUG_RELATIVE_POINTERS - use 32-bit pointers relative to
|
|
the containing struct bug_entry for bug_addr and file.
|
|
CONFIG_DEBUG_BUGVERBOSE - emit full file+line information for each BUG
|
|
|
|
CONFIG_BUG and CONFIG_DEBUG_BUGVERBOSE are potentially user-settable
|
|
(though they're generally always on).
|
|
|
|
CONFIG_GENERIC_BUG is set by each architecture using this code.
|
|
|
|
To use this, your architecture must:
|
|
|
|
1. Set up the config options:
|
|
- Enable CONFIG_GENERIC_BUG if CONFIG_BUG
|
|
|
|
2. Implement BUG (and optionally BUG_ON, WARN, WARN_ON)
|
|
- Define HAVE_ARCH_BUG
|
|
- Implement BUG() to generate a faulting instruction
|
|
- NOTE: struct bug_entry does not have "file" or "line" entries
|
|
when CONFIG_DEBUG_BUGVERBOSE is not enabled, so you must generate
|
|
the values accordingly.
|
|
|
|
3. Implement the trap
|
|
- In the illegal instruction trap handler (typically), verify
|
|
that the fault was in kernel mode, and call report_bug()
|
|
- report_bug() will return whether it was a false alarm, a warning,
|
|
or an actual bug.
|
|
- You must implement the is_valid_bugaddr(bugaddr) callback which
|
|
returns true if the eip is a real kernel address, and it points
|
|
to the expected BUG trap instruction.
|
|
|
|
Jeremy Fitzhardinge <jeremy@goop.org> 2006
|
|
*/
|
|
|
|
#define pr_fmt(fmt) fmt
|
|
|
|
#include <linux/list.h>
|
|
#include <linux/module.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/bug.h>
|
|
#include <linux/sched.h>
|
|
|
|
extern const struct bug_entry __start___bug_table[], __stop___bug_table[];
|
|
|
|
static inline unsigned long bug_addr(const struct bug_entry *bug)
|
|
{
|
|
#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
|
|
return bug->bug_addr;
|
|
#else
|
|
return (unsigned long)bug + bug->bug_addr_disp;
|
|
#endif
|
|
}
|
|
|
|
#ifdef CONFIG_MODULES
|
|
/* Updates are protected by module mutex */
|
|
static LIST_HEAD(module_bug_list);
|
|
|
|
static const struct bug_entry *module_find_bug(unsigned long bugaddr)
|
|
{
|
|
struct module *mod;
|
|
const struct bug_entry *bug = NULL;
|
|
|
|
rcu_read_lock_sched();
|
|
list_for_each_entry_rcu(mod, &module_bug_list, bug_list) {
|
|
unsigned i;
|
|
|
|
bug = mod->bug_table;
|
|
for (i = 0; i < mod->num_bugs; ++i, ++bug)
|
|
if (bugaddr == bug_addr(bug))
|
|
goto out;
|
|
}
|
|
bug = NULL;
|
|
out:
|
|
rcu_read_unlock_sched();
|
|
|
|
return bug;
|
|
}
|
|
|
|
void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
|
|
struct module *mod)
|
|
{
|
|
char *secstrings;
|
|
unsigned int i;
|
|
|
|
lockdep_assert_held(&module_mutex);
|
|
|
|
mod->bug_table = NULL;
|
|
mod->num_bugs = 0;
|
|
|
|
/* Find the __bug_table section, if present */
|
|
secstrings = (char *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
|
|
for (i = 1; i < hdr->e_shnum; i++) {
|
|
if (strcmp(secstrings+sechdrs[i].sh_name, "__bug_table"))
|
|
continue;
|
|
mod->bug_table = (void *) sechdrs[i].sh_addr;
|
|
mod->num_bugs = sechdrs[i].sh_size / sizeof(struct bug_entry);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Strictly speaking this should have a spinlock to protect against
|
|
* traversals, but since we only traverse on BUG()s, a spinlock
|
|
* could potentially lead to deadlock and thus be counter-productive.
|
|
* Thus, this uses RCU to safely manipulate the bug list, since BUG
|
|
* must run in non-interruptive state.
|
|
*/
|
|
list_add_rcu(&mod->bug_list, &module_bug_list);
|
|
}
|
|
|
|
void module_bug_cleanup(struct module *mod)
|
|
{
|
|
lockdep_assert_held(&module_mutex);
|
|
list_del_rcu(&mod->bug_list);
|
|
}
|
|
|
|
#else
|
|
|
|
static inline const struct bug_entry *module_find_bug(unsigned long bugaddr)
|
|
{
|
|
return NULL;
|
|
}
|
|
#endif
|
|
|
|
const struct bug_entry *find_bug(unsigned long bugaddr)
|
|
{
|
|
const struct bug_entry *bug;
|
|
|
|
for (bug = __start___bug_table; bug < __stop___bug_table; ++bug)
|
|
if (bugaddr == bug_addr(bug))
|
|
return bug;
|
|
|
|
return module_find_bug(bugaddr);
|
|
}
|
|
|
|
enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs)
|
|
{
|
|
const struct bug_entry *bug;
|
|
const char *file;
|
|
unsigned line, warning;
|
|
|
|
if (!is_valid_bugaddr(bugaddr))
|
|
return BUG_TRAP_TYPE_NONE;
|
|
|
|
bug = find_bug(bugaddr);
|
|
|
|
file = NULL;
|
|
line = 0;
|
|
warning = 0;
|
|
|
|
if (bug) {
|
|
#ifdef CONFIG_DEBUG_BUGVERBOSE
|
|
#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
|
|
file = bug->file;
|
|
#else
|
|
file = (const char *)bug + bug->file_disp;
|
|
#endif
|
|
line = bug->line;
|
|
#endif
|
|
warning = (bug->flags & BUGFLAG_WARNING) != 0;
|
|
}
|
|
|
|
if (warning) {
|
|
/* this is a WARN_ON rather than BUG/BUG_ON */
|
|
__warn(file, line, (void *)bugaddr, BUG_GET_TAINT(bug), regs,
|
|
NULL);
|
|
return BUG_TRAP_TYPE_WARN;
|
|
}
|
|
|
|
printk(KERN_DEFAULT "------------[ cut here ]------------\n");
|
|
|
|
if (file)
|
|
pr_crit("kernel BUG at %s:%u!\n", file, line);
|
|
else
|
|
pr_crit("Kernel BUG at %p [verbose debug info unavailable]\n",
|
|
(void *)bugaddr);
|
|
|
|
return BUG_TRAP_TYPE_BUG;
|
|
}
|