Re: [PATCH v2] perf probe: Fix add event failed when 32-bit perf running in 64-bit kernel

[Masami Hiramatsu <mhiramat@kernel.org>]

On Thu, 15 Jul 2021 14:37:23 +0800
Yang Jihong <yangjihong1@huawei.com> wrote:

> The "address" member  of "struct probe_trace_point" uses long data type.
> If kernel is 64-bit and perf program is 32-bit, size of "address" variable is
> 32 bits. As a result, upper 32 bits of address read from kernel are truncated,
> An error occurs during address comparison in kprobe_warn_out_range function.
> 
> Before:
> 
>   # perf probe -a schedule
>   schedule is out of .text, skip it.
>     Error: Failed to add events.
> 
> Solution:
>   Change data type of "address" variable to u64 and change corresponding
> address printing and value assignment.
> 
> After:
> 
>   # perf.new.new probe -a schedule
>   Added new event:
>     probe:schedule       (on schedule)
> 
>   You can now use it in all perf tools, such as:
> 
>           perf record -e probe:schedule -aR sleep 1
> 
>   # perf probe -l
>     probe:schedule       (on schedule@kernel/sched/core.c)
>   # perf record -e probe:schedule -aR sleep 1
>   [ perf record: Woken up 1 times to write data ]
>   [ perf record: Captured and wrote 0.156 MB perf.data (1366 samples) ]
>   # perf report --stdio
>   # To display the perf.data header info, please use --header/--header-only options.
>   #
>   #
>   # Total Lost Samples: 0
>   #
>   # Samples: 1K of event 'probe:schedule'
>   # Event count (approx.): 1366
>   #
>   # Overhead  Command          Shared Object      Symbol
>   # ........  ...............  .................  ............
>   #
>        6.22%  migration/0      [kernel.kallsyms]  [k] schedule
>        6.22%  migration/1      [kernel.kallsyms]  [k] schedule
>        6.22%  migration/2      [kernel.kallsyms]  [k] schedule
>        6.22%  migration/3      [kernel.kallsyms]  [k] schedule
>        6.15%  migration/10     [kernel.kallsyms]  [k] schedule
>        6.15%  migration/11     [kernel.kallsyms]  [k] schedule
>        6.15%  migration/12     [kernel.kallsyms]  [k] schedule
>        6.15%  migration/13     [kernel.kallsyms]  [k] schedule
>        6.15%  migration/14     [kernel.kallsyms]  [k] schedule
>        6.15%  migration/15     [kernel.kallsyms]  [k] schedule
>        6.15%  migration/4      [kernel.kallsyms]  [k] schedule
>        6.15%  migration/5      [kernel.kallsyms]  [k] schedule
>        6.15%  migration/6      [kernel.kallsyms]  [k] schedule
>        6.15%  migration/7      [kernel.kallsyms]  [k] schedule
>        6.15%  migration/8      [kernel.kallsyms]  [k] schedule
>        6.15%  migration/9      [kernel.kallsyms]  [k] schedule
>        0.22%  rcu_sched        [kernel.kallsyms]  [k] schedule
>   ...
>   #
>   # (Cannot load tips.txt file, please install perf!)
>   #
> 

OK, this looks good to me :)

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>

Thank you!

> Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
> ---
> 
> Changes since v1:
>   - Change the data type of "addr" parameter of the cu_find_lineinfo and
> line_range_walk_cb functions to Dwarf_Addr.
>   - Update commit msg, perf probe -l shows then filename and line number.
> 
>  tools/perf/util/dwarf-aux.c    |  8 +++---
>  tools/perf/util/dwarf-aux.h    |  2 +-
>  tools/perf/util/probe-event.c  | 49 ++++++++++++++++------------------
>  tools/perf/util/probe-event.h  |  4 +--
>  tools/perf/util/probe-finder.c | 15 +++++------
>  tools/perf/util/probe-finder.h |  2 +-
>  6 files changed, 38 insertions(+), 42 deletions(-)
> 
> diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
> index 7d2ba8419b0c..609ca1671501 100644
> --- a/tools/perf/util/dwarf-aux.c
> +++ b/tools/perf/util/dwarf-aux.c
> @@ -113,14 +113,14 @@ static Dwarf_Line *cu_getsrc_die(Dwarf_Die *cu_die, Dwarf_Addr addr)
>   *
>   * Find a line number and file name for @addr in @cu_die.
>   */
> -int cu_find_lineinfo(Dwarf_Die *cu_die, unsigned long addr,
> -		    const char **fname, int *lineno)
> +int cu_find_lineinfo(Dwarf_Die *cu_die, Dwarf_Addr addr,
> +		     const char **fname, int *lineno)
>  {
>  	Dwarf_Line *line;
>  	Dwarf_Die die_mem;
>  	Dwarf_Addr faddr;
>  
> -	if (die_find_realfunc(cu_die, (Dwarf_Addr)addr, &die_mem)
> +	if (die_find_realfunc(cu_die, addr, &die_mem)
>  	    && die_entrypc(&die_mem, &faddr) == 0 &&
>  	    faddr == addr) {
>  		*fname = dwarf_decl_file(&die_mem);
> @@ -128,7 +128,7 @@ int cu_find_lineinfo(Dwarf_Die *cu_die, unsigned long addr,
>  		goto out;
>  	}
>  
> -	line = cu_getsrc_die(cu_die, (Dwarf_Addr)addr);
> +	line = cu_getsrc_die(cu_die, addr);
>  	if (line && dwarf_lineno(line, lineno) == 0) {
>  		*fname = dwarf_linesrc(line, NULL, NULL);
>  		if (!*fname)
> diff --git a/tools/perf/util/dwarf-aux.h b/tools/perf/util/dwarf-aux.h
> index cb99646843a9..7ee0fa19b5c4 100644
> --- a/tools/perf/util/dwarf-aux.h
> +++ b/tools/perf/util/dwarf-aux.h
> @@ -19,7 +19,7 @@ const char *cu_find_realpath(Dwarf_Die *cu_die, const char *fname);
>  const char *cu_get_comp_dir(Dwarf_Die *cu_die);
>  
>  /* Get a line number and file name for given address */
> -int cu_find_lineinfo(Dwarf_Die *cudie, unsigned long addr,
> +int cu_find_lineinfo(Dwarf_Die *cudie, Dwarf_Addr addr,
>  		     const char **fname, int *lineno);
>  
>  /* Walk on functions at given address */
> diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> index c14e1d228e56..691b7a0988c6 100644
> --- a/tools/perf/util/probe-event.c
> +++ b/tools/perf/util/probe-event.c
> @@ -237,8 +237,8 @@ static void clear_probe_trace_events(struct probe_trace_event *tevs, int ntevs)
>  		clear_probe_trace_event(tevs + i);
>  }
>  
> -static bool kprobe_blacklist__listed(unsigned long address);
> -static bool kprobe_warn_out_range(const char *symbol, unsigned long address)
> +static bool kprobe_blacklist__listed(u64 address);
> +static bool kprobe_warn_out_range(const char *symbol, u64 address)
>  {
>  	struct map *map;
>  	bool ret = false;
> @@ -398,8 +398,7 @@ static int find_alternative_probe_point(struct debuginfo *dinfo,
>  	pr_debug("Symbol %s address found : %" PRIx64 "\n",
>  			pp->function, address);
>  
> -	ret = debuginfo__find_probe_point(dinfo, (unsigned long)address,
> -					  result);
> +	ret = debuginfo__find_probe_point(dinfo, address, result);
>  	if (ret <= 0)
>  		ret = (!ret) ? -ENOENT : ret;
>  	else {
> @@ -587,7 +586,7 @@ static void debuginfo_cache__exit(void)
>  }
>  
>  
> -static int get_text_start_address(const char *exec, unsigned long *address,
> +static int get_text_start_address(const char *exec, u64 *address,
>  				  struct nsinfo *nsi)
>  {
>  	Elf *elf;
> @@ -632,7 +631,7 @@ static int find_perf_probe_point_from_dwarf(struct probe_trace_point *tp,
>  					    bool is_kprobe)
>  {
>  	struct debuginfo *dinfo = NULL;
> -	unsigned long stext = 0;
> +	u64 stext = 0;
>  	u64 addr = tp->address;
>  	int ret = -ENOENT;
>  
> @@ -660,8 +659,7 @@ static int find_perf_probe_point_from_dwarf(struct probe_trace_point *tp,
>  
>  	dinfo = debuginfo_cache__open(tp->module, verbose <= 0);
>  	if (dinfo)
> -		ret = debuginfo__find_probe_point(dinfo,
> -						 (unsigned long)addr, pp);
> +		ret = debuginfo__find_probe_point(dinfo, addr, pp);
>  	else
>  		ret = -ENOENT;
>  
> @@ -676,7 +674,7 @@ static int find_perf_probe_point_from_dwarf(struct probe_trace_point *tp,
>  
>  /* Adjust symbol name and address */
>  static int post_process_probe_trace_point(struct probe_trace_point *tp,
> -					   struct map *map, unsigned long offs)
> +					   struct map *map, u64 offs)
>  {
>  	struct symbol *sym;
>  	u64 addr = tp->address - offs;
> @@ -719,7 +717,7 @@ post_process_offline_probe_trace_events(struct probe_trace_event *tevs,
>  					int ntevs, const char *pathname)
>  {
>  	struct map *map;
> -	unsigned long stext = 0;
> +	u64 stext = 0;
>  	int i, ret = 0;
>  
>  	/* Prepare a map for offline binary */
> @@ -745,7 +743,7 @@ static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs,
>  					  struct nsinfo *nsi)
>  {
>  	int i, ret = 0;
> -	unsigned long stext = 0;
> +	u64 stext = 0;
>  
>  	if (!exec)
>  		return 0;
> @@ -790,7 +788,7 @@ post_process_module_probe_trace_events(struct probe_trace_event *tevs,
>  	mod_name = find_module_name(module);
>  	for (i = 0; i < ntevs; i++) {
>  		ret = post_process_probe_trace_point(&tevs[i].point,
> -						map, (unsigned long)text_offs);
> +						map, text_offs);
>  		if (ret < 0)
>  			break;
>  		tevs[i].point.module =
> @@ -1534,7 +1532,7 @@ static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev)
>  		 * so tmp[1] should always valid (but could be '\0').
>  		 */
>  		if (tmp && !strncmp(tmp, "0x", 2)) {
> -			pp->abs_address = strtoul(pp->function, &tmp, 0);
> +			pp->abs_address = strtoull(pp->function, &tmp, 0);
>  			if (*tmp != '\0') {
>  				semantic_error("Invalid absolute address.\n");
>  				return -EINVAL;
> @@ -1909,7 +1907,7 @@ int parse_probe_trace_command(const char *cmd, struct probe_trace_event *tev)
>  			argv[i] = NULL;
>  			argc -= 1;
>  		} else
> -			tp->address = strtoul(fmt1_str, NULL, 0);
> +			tp->address = strtoull(fmt1_str, NULL, 0);
>  	} else {
>  		/* Only the symbol-based probe has offset */
>  		tp->symbol = strdup(fmt1_str);
> @@ -2155,7 +2153,7 @@ synthesize_uprobe_trace_def(struct probe_trace_point *tp, struct strbuf *buf)
>  		return -EINVAL;
>  
>  	/* Use the tp->address for uprobes */
> -	err = strbuf_addf(buf, "%s:0x%lx", tp->module, tp->address);
> +	err = strbuf_addf(buf, "%s:0x%" PRIx64, tp->module, tp->address);
>  
>  	if (err >= 0 && tp->ref_ctr_offset) {
>  		if (!uprobe_ref_ctr_is_supported())
> @@ -2170,7 +2168,7 @@ synthesize_kprobe_trace_def(struct probe_trace_point *tp, struct strbuf *buf)
>  {
>  	if (!strncmp(tp->symbol, "0x", 2)) {
>  		/* Absolute address. See try_to_find_absolute_address() */
> -		return strbuf_addf(buf, "%s%s0x%lx", tp->module ?: "",
> +		return strbuf_addf(buf, "%s%s0x%" PRIx64, tp->module ?: "",
>  				  tp->module ? ":" : "", tp->address);
>  	} else {
>  		return strbuf_addf(buf, "%s%s%s+%lu", tp->module ?: "",
> @@ -2269,7 +2267,7 @@ static int convert_to_perf_probe_point(struct probe_trace_point *tp,
>  		pp->function = strdup(tp->symbol);
>  		pp->offset = tp->offset;
>  	} else {
> -		ret = e_snprintf(buf, 128, "0x%" PRIx64, (u64)tp->address);
> +		ret = e_snprintf(buf, 128, "0x%" PRIx64, tp->address);
>  		if (ret < 0)
>  			return ret;
>  		pp->function = strdup(buf);
> @@ -2450,8 +2448,8 @@ void clear_probe_trace_event(struct probe_trace_event *tev)
>  
>  struct kprobe_blacklist_node {
>  	struct list_head list;
> -	unsigned long start;
> -	unsigned long end;
> +	u64 start;
> +	u64 end;
>  	char *symbol;
>  };
>  
> @@ -2496,7 +2494,7 @@ static int kprobe_blacklist__load(struct list_head *blacklist)
>  		}
>  		INIT_LIST_HEAD(&node->list);
>  		list_add_tail(&node->list, blacklist);
> -		if (sscanf(buf, "0x%lx-0x%lx", &node->start, &node->end) != 2) {
> +		if (sscanf(buf, "0x%" PRIx64 "-0x%" PRIx64, &node->start, &node->end) != 2) {
>  			ret = -EINVAL;
>  			break;
>  		}
> @@ -2512,7 +2510,7 @@ static int kprobe_blacklist__load(struct list_head *blacklist)
>  			ret = -ENOMEM;
>  			break;
>  		}
> -		pr_debug2("Blacklist: 0x%lx-0x%lx, %s\n",
> +		pr_debug2("Blacklist: 0x%" PRIx64 "-0x%" PRIx64 ", %s\n",
>  			  node->start, node->end, node->symbol);
>  		ret++;
>  	}
> @@ -2524,8 +2522,7 @@ static int kprobe_blacklist__load(struct list_head *blacklist)
>  }
>  
>  static struct kprobe_blacklist_node *
> -kprobe_blacklist__find_by_address(struct list_head *blacklist,
> -				  unsigned long address)
> +kprobe_blacklist__find_by_address(struct list_head *blacklist, u64 address)
>  {
>  	struct kprobe_blacklist_node *node;
>  
> @@ -2553,7 +2550,7 @@ static void kprobe_blacklist__release(void)
>  	kprobe_blacklist__delete(&kprobe_blacklist);
>  }
>  
> -static bool kprobe_blacklist__listed(unsigned long address)
> +static bool kprobe_blacklist__listed(u64 address)
>  {
>  	return !!kprobe_blacklist__find_by_address(&kprobe_blacklist, address);
>  }
> @@ -3221,7 +3218,7 @@ static int try_to_find_absolute_address(struct perf_probe_event *pev,
>  	 * In __add_probe_trace_events, a NULL symbol is interpreted as
>  	 * invalid.
>  	 */
> -	if (asprintf(&tp->symbol, "0x%lx", tp->address) < 0)
> +	if (asprintf(&tp->symbol, "0x%" PRIx64, tp->address) < 0)
>  		goto errout;
>  
>  	/* For kprobe, check range */
> @@ -3232,7 +3229,7 @@ static int try_to_find_absolute_address(struct perf_probe_event *pev,
>  		goto errout;
>  	}
>  
> -	if (asprintf(&tp->realname, "abs_%lx", tp->address) < 0)
> +	if (asprintf(&tp->realname, "abs_%" PRIx64, tp->address) < 0)
>  		goto errout;
>  
>  	if (pev->target) {
> diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
> index 65769d7949a3..8ad5b1579f1d 100644
> --- a/tools/perf/util/probe-event.h
> +++ b/tools/perf/util/probe-event.h
> @@ -33,7 +33,7 @@ struct probe_trace_point {
>  	char		*module;	/* Module name */
>  	unsigned long	offset;		/* Offset from symbol */
>  	unsigned long	ref_ctr_offset;	/* SDT reference counter offset */
> -	unsigned long	address;	/* Actual address of the trace point */
> +	u64		address;	/* Actual address of the trace point */
>  	bool		retprobe;	/* Return probe flag */
>  };
>  
> @@ -70,7 +70,7 @@ struct perf_probe_point {
>  	bool		retprobe;	/* Return probe flag */
>  	char		*lazy_line;	/* Lazy matching pattern */
>  	unsigned long	offset;		/* Offset from function entry */
> -	unsigned long	abs_address;	/* Absolute address of the point */
> +	u64		abs_address;	/* Absolute address of the point */
>  };
>  
>  /* Perf probe probing argument field chain */
> diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
> index 02ef0d78053b..50d861a80f57 100644
> --- a/tools/perf/util/probe-finder.c
> +++ b/tools/perf/util/probe-finder.c
> @@ -668,7 +668,7 @@ static int convert_to_trace_point(Dwarf_Die *sp_die, Dwfl_Module *mod,
>  	}
>  
>  	tp->offset = (unsigned long)(paddr - eaddr);
> -	tp->address = (unsigned long)paddr;
> +	tp->address = paddr;
>  	tp->symbol = strdup(symbol);
>  	if (!tp->symbol)
>  		return -ENOMEM;
> @@ -1707,7 +1707,7 @@ int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs,
>  }
>  
>  /* Reverse search */
> -int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr,
> +int debuginfo__find_probe_point(struct debuginfo *dbg, u64 addr,
>  				struct perf_probe_point *ppt)
>  {
>  	Dwarf_Die cudie, spdie, indie;
> @@ -1720,14 +1720,14 @@ int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr,
>  		addr += baseaddr;
>  	/* Find cu die */
>  	if (!dwarf_addrdie(dbg->dbg, (Dwarf_Addr)addr, &cudie)) {
> -		pr_warning("Failed to find debug information for address %lx\n",
> +		pr_warning("Failed to find debug information for address %" PRIx64 "\n",
>  			   addr);
>  		ret = -EINVAL;
>  		goto end;
>  	}
>  
>  	/* Find a corresponding line (filename and lineno) */
> -	cu_find_lineinfo(&cudie, addr, &fname, &lineno);
> +	cu_find_lineinfo(&cudie, (Dwarf_Addr)addr, &fname, &lineno);
>  	/* Don't care whether it failed or not */
>  
>  	/* Find a corresponding function (name, baseline and baseaddr) */
> @@ -1742,7 +1742,7 @@ int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr,
>  		}
>  
>  		fname = dwarf_decl_file(&spdie);
> -		if (addr == (unsigned long)baseaddr) {
> +		if (addr == baseaddr) {
>  			/* Function entry - Relative line number is 0 */
>  			lineno = baseline;
>  			goto post;
> @@ -1788,7 +1788,7 @@ int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr,
>  	if (lineno)
>  		ppt->line = lineno - baseline;
>  	else if (basefunc) {
> -		ppt->offset = addr - (unsigned long)baseaddr;
> +		ppt->offset = addr - baseaddr;
>  		func = basefunc;
>  	}
>  
> @@ -1828,8 +1828,7 @@ static int line_range_add_line(const char *src, unsigned int lineno,
>  }
>  
>  static int line_range_walk_cb(const char *fname, int lineno,
> -			      Dwarf_Addr addr __maybe_unused,
> -			      void *data)
> +			      Dwarf_Addr addr, void *data)
>  {
>  	struct line_finder *lf = data;
>  	const char *__fname;
> diff --git a/tools/perf/util/probe-finder.h b/tools/perf/util/probe-finder.h
> index 2febb5875678..8bc1c80d3c1c 100644
> --- a/tools/perf/util/probe-finder.h
> +++ b/tools/perf/util/probe-finder.h
> @@ -46,7 +46,7 @@ int debuginfo__find_trace_events(struct debuginfo *dbg,
>  				 struct probe_trace_event **tevs);
>  
>  /* Find a perf_probe_point from debuginfo */
> -int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr,
> +int debuginfo__find_probe_point(struct debuginfo *dbg, u64 addr,
>  				struct perf_probe_point *ppt);
>  
>  int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs,
> -- 
> 2.30.GIT
> 


-- 
Masami Hiramatsu <mhiramat@kernel.org>