Skip to content

Commit

Permalink
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel…
Browse files Browse the repository at this point in the history
…/git/jikos/trivial

Pull fixup for trivial branch from Jiri Kosina:
 "Unfortunately I made a mistake when merging into for-linus branch, and
  omitted one pre-requisity patch for a few other patches (which have
  been Acked by the appropriate maintainers) in the series.  Mea culpa
  maxima, sorry for that."

The trivial branch added %pSR usage before actually teaching vsnprintf()
about the 'R' part of %pSR.  The 'R' causes the symbol translation to do
a "__builtin_extract_return_addr()" before symbol lookup.

That said, on most architectures __builtin_extract_return_addr() isn't
likely to do anything special, so it probably is not normally
noticeable.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  vsprintf: Add extension %pSR - print_symbol replacement
  • Loading branch information
Linus Torvalds committed Apr 30, 2013
2 parents 5aa1c98 + b0d33c2 commit 3094566
Show file tree
Hide file tree
Showing 2 changed files with 15 additions and 5 deletions.
2 changes: 2 additions & 0 deletions Documentation/printk-formats.txt
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,8 @@ Symbols/Function Pointers:
%pF versatile_init+0x0/0x110
%pf versatile_init
%pS versatile_init+0x0/0x110
%pSR versatile_init+0x9/0x110
(with __builtin_extract_return_addr() translation)
%ps versatile_init
%pB prev_fn_of_versatile_init+0x88/0x88

Expand Down
18 changes: 13 additions & 5 deletions lib/vsprintf.c
Original file line number Diff line number Diff line change
Expand Up @@ -534,14 +534,21 @@ char *string(char *buf, char *end, const char *s, struct printf_spec spec)

static noinline_for_stack
char *symbol_string(char *buf, char *end, void *ptr,
struct printf_spec spec, char ext)
struct printf_spec spec, const char *fmt)
{
unsigned long value = (unsigned long) ptr;
unsigned long value;
#ifdef CONFIG_KALLSYMS
char sym[KSYM_SYMBOL_LEN];
if (ext == 'B')
#endif

if (fmt[1] == 'R')
ptr = __builtin_extract_return_addr(ptr);
value = (unsigned long)ptr;

#ifdef CONFIG_KALLSYMS
if (*fmt == 'B')
sprint_backtrace(sym, value);
else if (ext != 'f' && ext != 's')
else if (*fmt != 'f' && *fmt != 's')
sprint_symbol(sym, value);
else
sprint_symbol_no_offset(sym, value);
Expand Down Expand Up @@ -987,6 +994,7 @@ int kptr_restrict __read_mostly;
* - 'f' For simple symbolic function names without offset
* - 'S' For symbolic direct pointers with offset
* - 's' For symbolic direct pointers without offset
* - '[FfSs]R' as above with __builtin_extract_return_addr() translation
* - 'B' For backtraced symbolic direct pointers with offset
* - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
* - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
Expand Down Expand Up @@ -1060,7 +1068,7 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
case 'S':
case 's':
case 'B':
return symbol_string(buf, end, ptr, spec, *fmt);
return symbol_string(buf, end, ptr, spec, fmt);
case 'R':
case 'r':
return resource_string(buf, end, ptr, spec, fmt);
Expand Down

0 comments on commit 3094566

Please sign in to comment.