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Diffstat (limited to 'arch/parisc/kernel/unwind.c')
-rw-r--r--arch/parisc/kernel/unwind.c116
1 files changed, 82 insertions, 34 deletions
diff --git a/arch/parisc/kernel/unwind.c b/arch/parisc/kernel/unwind.c
index db141108412..ddd988b267a 100644
--- a/arch/parisc/kernel/unwind.c
+++ b/arch/parisc/kernel/unwind.c
@@ -8,14 +8,17 @@
* understand what is happening here
*/
-#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/init.h>
+#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/kallsyms.h>
+#include <linux/sort.h>
#include <asm/uaccess.h>
#include <asm/assembly.h>
+#include <asm/asm-offsets.h>
+#include <asm/ptrace.h>
#include <asm/unwind.h>
@@ -26,6 +29,8 @@
#define dbg(x...)
#endif
+#define KERNEL_START (KERNEL_BINARY_TEXT_START)
+
extern struct unwind_table_entry __start___unwind[];
extern struct unwind_table_entry __stop___unwind[];
@@ -35,7 +40,7 @@ static spinlock_t unwind_lock;
* we can call unwind_init as early in the bootup process as
* possible (before the slab allocator is initialized)
*/
-static struct unwind_table kernel_unwind_table;
+static struct unwind_table kernel_unwind_table __read_mostly;
static LIST_HEAD(unwind_tables);
static inline const struct unwind_table_entry *
@@ -75,8 +80,11 @@ find_unwind_entry(unsigned long addr)
if (addr >= table->start &&
addr <= table->end)
e = find_unwind_entry_in_table(table, addr);
- if (e)
+ if (e) {
+ /* Move-to-front to exploit common traces */
+ list_move(&table->list, &unwind_tables);
break;
+ }
}
return e;
@@ -111,24 +119,18 @@ unwind_table_init(struct unwind_table *table, const char *name,
}
}
+static int cmp_unwind_table_entry(const void *a, const void *b)
+{
+ return ((const struct unwind_table_entry *)a)->region_start
+ - ((const struct unwind_table_entry *)b)->region_start;
+}
+
static void
unwind_table_sort(struct unwind_table_entry *start,
struct unwind_table_entry *finish)
{
- struct unwind_table_entry el, *p, *q;
-
- for (p = start + 1; p < finish; ++p) {
- if (p[0].region_start < p[-1].region_start) {
- el = *p;
- q = p;
- do {
- q[0] = q[-1];
- --q;
- } while (q > start &&
- el.region_start < q[-1].region_start);
- *q = el;
- }
- }
+ sort(start, finish - start, sizeof(struct unwind_table_entry),
+ cmp_unwind_table_entry, NULL);
}
struct unwind_table *
@@ -166,7 +168,7 @@ void unwind_table_remove(struct unwind_table *table)
}
/* Called from setup_arch to import the kernel unwind info */
-static int unwind_init(void)
+int __init unwind_init(void)
{
long start, stop;
register unsigned long gp __asm__ ("r27");
@@ -197,6 +199,29 @@ static int unwind_init(void)
return 0;
}
+#ifdef CONFIG_64BIT
+#define get_func_addr(fptr) fptr[2]
+#else
+#define get_func_addr(fptr) fptr[0]
+#endif
+
+static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int frame_size)
+{
+ extern void handle_interruption(int, struct pt_regs *);
+ static unsigned long *hi = (unsigned long *)&handle_interruption;
+
+ if (pc == get_func_addr(hi)) {
+ struct pt_regs *regs = (struct pt_regs *)(info->sp - frame_size - PT_SZ_ALGN);
+ dbg("Unwinding through handle_interruption()\n");
+ info->prev_sp = regs->gr[30];
+ info->prev_ip = regs->iaoq[0];
+
+ return 1;
+ }
+
+ return 0;
+}
+
static void unwind_frame_regs(struct unwind_frame_info *info)
{
const struct unwind_table_entry *e;
@@ -208,19 +233,17 @@ static void unwind_frame_regs(struct unwind_frame_info *info)
e = find_unwind_entry(info->ip);
if (e == NULL) {
unsigned long sp;
- extern char _stext[], _etext[];
dbg("Cannot find unwind entry for 0x%lx; forced unwinding\n", info->ip);
#ifdef CONFIG_KALLSYMS
/* Handle some frequent special cases.... */
{
- char symname[KSYM_NAME_LEN+1];
+ char symname[KSYM_NAME_LEN];
char *modname;
- unsigned long symsize, offset;
- kallsyms_lookup(info->ip, &symsize, &offset,
- &modname, symname);
+ kallsyms_lookup(info->ip, NULL, NULL, &modname,
+ symname);
dbg("info->ip = 0x%lx, name = %s\n", info->ip, symname);
@@ -257,8 +280,7 @@ static void unwind_frame_regs(struct unwind_frame_info *info)
break;
info->prev_ip = tmp;
sp = info->prev_sp;
- } while (info->prev_ip < (unsigned long)_stext ||
- info->prev_ip > (unsigned long)_etext);
+ } while (!kernel_text_address(info->prev_ip));
info->rp = 0;
@@ -311,13 +333,15 @@ static void unwind_frame_regs(struct unwind_frame_info *info)
}
}
- info->prev_sp = info->sp - frame_size;
- if (e->Millicode)
- info->rp = info->r31;
- else if (rpoffset)
- info->rp = *(unsigned long *)(info->prev_sp - rpoffset);
- info->prev_ip = info->rp;
- info->rp = 0;
+ if (!unwind_special(info, e->region_start, frame_size)) {
+ info->prev_sp = info->sp - frame_size;
+ if (e->Millicode)
+ info->rp = info->r31;
+ else if (rpoffset)
+ info->rp = *(unsigned long *)(info->prev_sp - rpoffset);
+ info->prev_ip = info->rp;
+ info->rp = 0;
+ }
dbg("analyzing func @ %lx, setting prev_sp=%lx "
"prev_ip=%lx npc=%lx\n", info->ip, info->prev_sp,
@@ -344,7 +368,7 @@ void unwind_frame_init_from_blocked_task(struct unwind_frame_info *info, struct
struct pt_regs *r = &t->thread.regs;
struct pt_regs *r2;
- r2 = (struct pt_regs *)kmalloc(sizeof(struct pt_regs), GFP_KERNEL);
+ r2 = kmalloc(sizeof(struct pt_regs), GFP_ATOMIC);
if (!r2)
return;
*r2 = *r;
@@ -390,4 +414,28 @@ int unwind_to_user(struct unwind_frame_info *info)
return ret;
}
-module_init(unwind_init);
+unsigned long return_address(unsigned int level)
+{
+ struct unwind_frame_info info;
+ struct pt_regs r;
+ unsigned long sp;
+
+ /* initialize unwind info */
+ asm volatile ("copy %%r30, %0" : "=r"(sp));
+ memset(&r, 0, sizeof(struct pt_regs));
+ r.iaoq[0] = (unsigned long) current_text_addr();
+ r.gr[2] = (unsigned long) __builtin_return_address(0);
+ r.gr[30] = sp;
+ unwind_frame_init(&info, current, &r);
+
+ /* unwind stack */
+ ++level;
+ do {
+ if (unwind_once(&info) < 0 || info.ip == 0)
+ return 0;
+ if (!kernel_text_address(info.ip))
+ return 0;
+ } while (info.ip && level--);
+
+ return info.ip;
+}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-05 18:37:48 +0000