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kallsyms: Take callthunks into account

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Since the pre-symbol function padding is an integral part of the
symbol make kallsyms report it as part of the symbol by reporting it
as sym-x instead of prev_sym+y.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220915111148.409656012@infradead.org
This commit is contained in:
Peter Zijlstra 2022-09-15 13:11:32 +02:00
parent 7825451fa4
commit f138918162
1 changed files with 40 additions and 5 deletions
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45
kernel/kallsyms.c
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@ -293,6 +293,12 @@ static unsigned long get_symbol_pos(unsigned long addr,
return low;
}
#ifdef CONFIG_FUNCTION_PADDING_BYTES
#define PADDING_BYTES CONFIG_FUNCTION_PADDING_BYTES
#else
#define PADDING_BYTES 0
#endif
/*
* Lookup an address but don't bother to find any names.
*/
@ -300,13 +306,25 @@ int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize,
unsigned long *offset)
{
char namebuf[KSYM_NAME_LEN];
int ret;
addr += PADDING_BYTES;
if (is_ksym_addr(addr)) {
get_symbol_pos(addr, symbolsize, offset);
return 1;
ret = 1;
goto found;
}
return !!module_address_lookup(addr, symbolsize, offset, NULL, NULL, namebuf) ||
!!__bpf_address_lookup(addr, symbolsize, offset, namebuf);
ret = !!module_address_lookup(addr, symbolsize, offset, NULL, NULL, namebuf);
if (!ret) {
ret = !!__bpf_address_lookup(addr, symbolsize,
offset, namebuf);
}
found:
if (ret && offset)
*offset -= PADDING_BYTES;
return ret;
}
static const char *kallsyms_lookup_buildid(unsigned long addr,
@ -319,6 +337,8 @@ static const char *kallsyms_lookup_buildid(unsigned long addr,
namebuf[KSYM_NAME_LEN - 1] = 0;
namebuf[0] = 0;
addr += PADDING_BYTES;
if (is_ksym_addr(addr)) {
unsigned long pos;
@ -348,6 +368,8 @@ static const char *kallsyms_lookup_buildid(unsigned long addr,
found:
cleanup_symbol_name(namebuf);
if (ret && offset)
*offset -= PADDING_BYTES;
return ret;
}
@ -374,6 +396,8 @@ int lookup_symbol_name(unsigned long addr, char *symname)
symname[0] = '\0';
symname[KSYM_NAME_LEN - 1] = '\0';
addr += PADDING_BYTES;
if (is_ksym_addr(addr)) {
unsigned long pos;
@ -401,6 +425,8 @@ int lookup_symbol_attrs(unsigned long addr, unsigned long *size,
name[0] = '\0';
name[KSYM_NAME_LEN - 1] = '\0';
addr += PADDING_BYTES;
if (is_ksym_addr(addr)) {
unsigned long pos;
@ -417,6 +443,8 @@ int lookup_symbol_attrs(unsigned long addr, unsigned long *size,
return res;
found:
if (offset)
*offset -= PADDING_BYTES;
cleanup_symbol_name(name);
return 0;
}
@ -442,8 +470,15 @@ static int __sprint_symbol(char *buffer, unsigned long address,
len = strlen(buffer);
offset -= symbol_offset;
if (add_offset)
len += sprintf(buffer + len, "+%#lx/%#lx", offset, size);
if (add_offset) {
char s = '+';
if ((long)offset < 0) {
s = '-';
offset = 0UL - offset;
}
len += sprintf(buffer + len, "%c%#lx/%#lx", s, offset, size);
}
if (modname) {
len += sprintf(buffer + len, " [%s", modname);