Skip to contentSkip to conversation

Some build fixes

PATCH Applied Arnaldo Carvalho de Melo 2 participants 7 messages Mar 10, 2025 – Mar 13, 2025 perf events

lore
Share & tools
lore

Arnaldo Carvalho de Melo

author maintainer
#0 lore raw

cover Some build fixes

From: Arnaldo Carvalho de Melo <[email protected]>

Hi Namhyung,

Some fixes I noticed while building with my set of containers.

Best regards,

- Arnaldo

Arnaldo Carvalho de Melo (3):
libapi: Add missing header with NAME_MAX define to io_dir.h
perf units: Fix insufficient array space
perf hist stdio: Do bounds check when printing callchains to avoid UB with new gcc versions

 tools/lib/api/io_dir.h     | 1 +
 tools/perf/ui/stdio/hist.c | 4 ++++
 tools/perf/util/units.c    | 2 +-
 3 files changed, 6 insertions(+), 1 deletion(-)
Signature · 1 line
2.48.1
author maintainer
#1 lore raw

PATCH 1/3 libapi: Add missing header with NAME_MAX define to io_dir.h

From: Arnaldo Carvalho de Melo <[email protected]>

Most systems get this indirectly, but some odd cases (some musl libc systems) can't find it, so just add the header where NAME_MAX is defined to avoid that.

Fixes d118b08f7eee6d6f ("tools lib api: Add io_dir an allocation free readdir alternative")
Cc Adrian Hunter <[email protected]>
Cc Ian Rogers <[email protected]>
Cc James Clark <[email protected]>
Cc Jiri Olsa <[email protected]>
Cc Kan Liang <[email protected]>
Cc Namhyung Kim <[email protected]>
Signed-off-by Arnaldo Carvalho de Melo <[email protected]>
---
 tools/lib/api/io_dir.h | 1 +
 1 file changed, 1 insertion(+)
tools/lib/api/io_dir.h +1 -0
index aab73393d2a217ab..ef83e967e48c59f7 100644
@@ -11,6 +11,7 @@
 #include <unistd.h>
 #include <sys/stat.h>
 #include <sys/syscall.h>
+#include <linux/limits.h>
 
 #if !defined(SYS_getdents64)
 #if defined(__x86_64__) || defined(__arm__)
Signature · 1 line
2.48.1
author maintainer
#2 lore raw

PATCH 2/3 perf units: Fix insufficient array space

In reply to Arnaldo Carvalho de Melo

From: Arnaldo Carvalho de Melo <[email protected]>

No need to specify the array size, let the compiler figure that out.

This addresses this compiler warning that was noticed while build testing on fedora rawhide:

31 15.81 fedora:rawhide : FAIL gcc version 15.0.1 20250225 (Red Hat 15.0.1-0) (GCC)
util/units.c: In function 'unit_number__scnprintf':
util/units.c:67:24: error: initializer-string for array of 'char' is too long [-Werror=unterminated-string-initialization]
67 | char unit[4] = "BKMG";
| ^~~~~~
cc1: all warnings being treated as errors

Fixes 9808143ba2e54818 ("perf tools: Add unit_number__scnprintf function")
Cc Adrian Hunter <[email protected]>
Cc Ian Rogers <[email protected]>
Cc James Clark <[email protected]>
Cc Jiri Olsa <[email protected]>
Cc Kan Liang <[email protected]>
Cc Namhyung Kim <[email protected]>
Signed-off-by Arnaldo Carvalho de Melo <[email protected]>
---
 tools/perf/util/units.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
tools/perf/util/units.c +1 -1
index 32c39cfe209b3bba..4c6a86e1cb54b222 100644
@@ -64,7 +64,7 @@ unsigned long convert_unit(unsigned long value, char *unit)
 
 int unit_number__scnprintf(char *buf, size_t size, u64 n)
 {
-	char unit[4] = "BKMG";
+	char unit[] = "BKMG";
 	int i = 0;
 
 	while (((n / 1024) > 1) && (i < 3)) {
Signature · 1 line
2.48.1
author maintainer
#3 lore raw

PATCH 3/3 perf hist stdio: Do bounds check when printing callchains to avoid UB with new gcc versions

In reply to Arnaldo Carvalho de Melo

From: Arnaldo Carvalho de Melo <[email protected]>

Do a simple bounds check to avoid this on new gcc versions:

31 15.81 fedora:rawhide : FAIL gcc version 15.0.1 20250225 (Red Hat 15.0.1-0) (GCC)
In function 'callchain__fprintf_left_margin',
inlined from 'callchain__fprintf_graph.constprop' at ui/stdio/hist.c:246:12:
ui/stdio/hist.c:27:39: error: iteration 2147483647 invokes undefined behavior [-Werror=aggressive-loop-optimizations]
27 | for (i = 0; i < left_margin; i++)
| ~^~
ui/stdio/hist.c:27:23: note: within this loop
27 | for (i = 0; i < left_margin; i++)
| ~~^~~~~~~~~~~~~
cc1: all warnings being treated as errors
--
util/units.c: In function 'unit_number__scnprintf':
util/units.c:67:24: error: initializer-string for array of 'char' is too long [-Werror=unterminated-string-initialization]
67 | char unit[4] = "BKMG";
| ^~~~~~
cc1: all warnings being treated as errors

Cc Adrian Hunter <[email protected]>
Cc Ian Rogers <[email protected]>
Cc James Clark <[email protected]>
Cc Jiri Olsa <[email protected]>
Cc Kan Liang <[email protected]>
Cc Namhyung Kim <[email protected]>
Signed-off-by Arnaldo Carvalho de Melo <[email protected]>
---
 tools/perf/ui/stdio/hist.c | 4 ++++
 1 file changed, 4 insertions(+)
tools/perf/ui/stdio/hist.c +4 -0
index 74b2c619c56c8ba3..7ac4b98e28bca82e 100644
@@ -1,4 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
+#include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <linux/string.h>

@@ -24,6 +25,9 @@ static size_t callchain__fprintf_left_margin(FILE *fp, int left_margin)
 	int i;
 	int ret = fprintf(fp, "            ");
 
+	if (left_margin > USHRT_MAX)
+		left_margin = USHRT_MAX;
+
 	for (i = 0; i < left_margin; i++)
 		ret += fprintf(fp, " ");
Signature · 1 line
2.48.1
maintainer
#4 lore raw

Re: [PATCH 3/3] perf hist stdio: Do bounds check when printing callchains to avoid UB with new gcc versions

Quoted 8 lines · Arnaldo Carvalho de Melo

From: Arnaldo Carvalho de Melo <[email protected]>

Do a simple bounds check to avoid this on new gcc versions:

31 15.81 fedora:rawhide : FAIL gcc version 15.0.1 20250225 (Red Hat 15.0.1-0) (GCC)
In function 'callchain__fprintf_left_margin',
inlined from 'callchain__fprintf_graph.constprop' at ui/stdio/hist.c:246:12:
ui/stdio/hist.c:27:39: error: iteration 2147483647 invokes undefined behavior [-Werror=aggressive-loop-optimizations]

Hmm.. does it warn about a signed integer overflow?

2147483647 is 0x7fffffff in hex and it should be INT_MAX. I'm not sure what is the problem.

Quoted 4 lines

27 | for (i = 0; i < left_margin; i++)
| ~^~
ui/stdio/hist.c:27:23: note: within this loop
27 | for (i = 0; i < left_margin; i++)

Quoted 8 lines

| ~~^~~~~~~~~~~~~
cc1: all warnings being treated as errors
--
util/units.c: In function 'unit_number__scnprintf':
util/units.c:67:24: error: initializer-string for array of 'char' is too long [-Werror=unterminated-string-initialization]
67 | char unit[4] = "BKMG";
| ^~~~~~
cc1: all warnings being treated as errors

This part belongs to the previous commit. :)

Quoted 35 lines
Cc Adrian Hunter <[email protected]>
Cc Ian Rogers <[email protected]>
Cc James Clark <[email protected]>
Cc Jiri Olsa <[email protected]>
Cc Kan Liang <[email protected]>
Cc Namhyung Kim <[email protected]>
Signed-off-by Arnaldo Carvalho de Melo <[email protected]>
---
 tools/perf/ui/stdio/hist.c | 4 ++++
 1 file changed, 4 insertions(+)
tools/perf/ui/stdio/hist.c +4 -0
index 74b2c619c56c8ba3..7ac4b98e28bca82e 100644
@@ -1,4 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
+#include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <linux/string.h>

@@ -24,6 +25,9 @@ static size_t callchain__fprintf_left_margin(FILE *fp, int left_margin)
 	int i;
 	int ret = fprintf(fp, "            ");
 
+	if (left_margin > USHRT_MAX)
+		left_margin = USHRT_MAX;
+
 	for (i = 0; i < left_margin; i++)
 		ret += fprintf(fp, " ");
Signature · 1 line
2.48.1
maintainer
#5 lore raw

Re: [PATCH 3/3] perf hist stdio: Do bounds check when printing callchains to avoid UB with new gcc versions

Quoted 10 lines · Namhyung Kim
Quoted 8 lines · Arnaldo Carvalho de Melo

From: Arnaldo Carvalho de Melo <[email protected]>

Do a simple bounds check to avoid this on new gcc versions:

31 15.81 fedora:rawhide : FAIL gcc version 15.0.1 20250225 (Red Hat 15.0.1-0) (GCC)
In function 'callchain__fprintf_left_margin',
inlined from 'callchain__fprintf_graph.constprop' at ui/stdio/hist.c:246:12:
ui/stdio/hist.c:27:39: error: iteration 2147483647 invokes undefined behavior [-Werror=aggressive-loop-optimizations]

Quoted 4 lines

Hmm.. does it warn about a signed integer overflow?

2147483647 is 0x7fffffff in hex and it should be INT_MAX. I'm not sure what is the problem.

Maybe the aggressive loop optimization can unroll the loop more than the INT_MAX...? Anyway the fix is simple and makes sense.

Quoted 15 lines
Quoted 14 lines

27 | for (i = 0; i < left_margin; i++)
| ~^~
ui/stdio/hist.c:27:23: note: within this loop
27 | for (i = 0; i < left_margin; i++)
| ~~^~~~~~~~~~~~~
cc1: all warnings being treated as errors
--
util/units.c: In function 'unit_number__scnprintf':
util/units.c:67:24: error: initializer-string for array of 'char' is too long [-Werror=unterminated-string-initialization]
67 | char unit[4] = "BKMG";
| ^~~~~~
cc1: all warnings being treated as errors

Quoted 1 line

This part belongs to the previous commit. :)

I'll drop this part.

Thanks,
Namhyung

Quoted 36 lines
Quoted 36 lines
Cc Adrian Hunter <[email protected]>
Cc Ian Rogers <[email protected]>
Cc James Clark <[email protected]>
Cc Jiri Olsa <[email protected]>
Cc Kan Liang <[email protected]>
Cc Namhyung Kim <[email protected]>
Signed-off-by Arnaldo Carvalho de Melo <[email protected]>
---
 tools/perf/ui/stdio/hist.c | 4 ++++
 1 file changed, 4 insertions(+)
tools/perf/ui/stdio/hist.c +4 -0
index 74b2c619c56c8ba3..7ac4b98e28bca82e 100644
@@ -1,4 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
+#include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <linux/string.h>

@@ -24,6 +25,9 @@ static size_t callchain__fprintf_left_margin(FILE *fp, int left_margin)
 	int i;
 	int ret = fprintf(fp, "            ");
 
+	if (left_margin > USHRT_MAX)
+		left_margin = USHRT_MAX;
+
 	for (i = 0; i < left_margin; i++)
 		ret += fprintf(fp, " ");
Signature · 1 line
2.48.1