diff mbox series

[08/10] tools/power turbostat: Fix 32-bit capabilities warning

Message ID fcaa681c03ea82193e60d7f2cdfd94fbbcd4cae9.1584679387.git.len.brown@intel.com (mailing list archive)
State Accepted, archived
Delegated to: Len Brown
Headers show
Series [01/10] tools/power turbostat: Support Cometlake | expand

Commit Message

Len Brown March 20, 2020, 5:22 a.m. UTC 
From: Len Brown <len.brown@intel.com>

warning: `turbostat' uses 32-bit capabilities (legacy support in use)

Signed-off-by: Len Brown <len.brown@intel.com>
---
 tools/power/x86/turbostat/Makefile    |  2 +-
 tools/power/x86/turbostat/turbostat.c | 46 +++++++++++++++++----------
 2 files changed, 31 insertions(+), 17 deletions(-)

Comments

Doug Smythies March 25, 2020, 12:50 a.m. UTC | #1 
Hi Len,

On 2020.03.24 22:23 Len Brown wrote:

> From: Len Brown <len.brown@intel.com>
>
> warning: `turbostat' uses 32-bit capabilities (legacy support in use)
>
> Signed-off-by: Len Brown <len.brown@intel.com>
> ---
>  tools/power/x86/turbostat/Makefile    |  2 +-
>  tools/power/x86/turbostat/turbostat.c | 46 +++++++++++++++++----------
>  2 files changed, 31 insertions(+), 17 deletions(-)

...

> +#include <sys/capability.h>


This seems to require a package, libcap-dev, to be installed.
I never needed it before.
Just F.Y.I.

... Doug
Len Brown March 25, 2020, 12:54 a.m. UTC | #2 
> +#include <sys/capability.h>

> This seems to require a package, libcap-dev, to be installed.

Yeah, sort of annoying that libcap-dev isn't installed by default.
I've added it to the list of stuff that I install on new machines before they are usable...
diff mbox series

Patch

diff --git a/tools/power/x86/turbostat/Makefile b/tools/power/x86/turbostat/Makefile
index 13f1e8b9ac52..2b6551269e43 100644
--- a/tools/power/x86/turbostat/Makefile
+++ b/tools/power/x86/turbostat/Makefile
@@ -16,7 +16,7 @@  override CFLAGS +=	-D_FORTIFY_SOURCE=2
 
 %: %.c
 	@mkdir -p $(BUILD_OUTPUT)
-	$(CC) $(CFLAGS) $< -o $(BUILD_OUTPUT)/$@ $(LDFLAGS)
+	$(CC) $(CFLAGS) $< -o $(BUILD_OUTPUT)/$@ $(LDFLAGS) -lcap
 
 .PHONY : clean
 clean :
diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index 3ecbf709a48c..77f89371ec5f 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -30,7 +30,7 @@ 
 #include <sched.h>
 #include <time.h>
 #include <cpuid.h>
-#include <linux/capability.h>
+#include <sys/capability.h>
 #include <errno.h>
 #include <math.h>
 
@@ -3150,28 +3150,42 @@  void check_dev_msr()
 			err(-5, "no /dev/cpu/0/msr, Try \"# modprobe msr\" ");
 }
 
-void check_permissions()
+/*
+ * check for CAP_SYS_RAWIO
+ * return 0 on success
+ * return 1 on fail
+ */
+int check_for_cap_sys_rawio(void)
 {
-	struct __user_cap_header_struct cap_header_data;
-	cap_user_header_t cap_header = &cap_header_data;
-	struct __user_cap_data_struct cap_data_data;
-	cap_user_data_t cap_data = &cap_data_data;
-	extern int capget(cap_user_header_t hdrp, cap_user_data_t datap);
-	int do_exit = 0;
-	char pathname[32];
+	cap_t caps;
+	cap_flag_value_t cap_flag_value;
 
-	/* check for CAP_SYS_RAWIO */
-	cap_header->pid = getpid();
-	cap_header->version = _LINUX_CAPABILITY_VERSION;
-	if (capget(cap_header, cap_data) < 0)
-		err(-6, "capget(2) failed");
+	caps = cap_get_proc();
+	if (caps == NULL)
+		err(-6, "cap_get_proc\n");
 
-	if ((cap_data->effective & (1 << CAP_SYS_RAWIO)) == 0) {
-		do_exit++;
+	if (cap_get_flag(caps, CAP_SYS_RAWIO, CAP_EFFECTIVE, &cap_flag_value))
+		err(-6, "cap_get\n");
+
+	if (cap_flag_value != CAP_SET) {
 		warnx("capget(CAP_SYS_RAWIO) failed,"
 			" try \"# setcap cap_sys_rawio=ep %s\"", progname);
+		return 1;
 	}
 
+	if (cap_free(caps) == -1)
+		err(-6, "cap_free\n");
+
+	return 0;
+}
+void check_permissions(void)
+{
+	int do_exit = 0;
+	char pathname[32];
+
+	/* check for CAP_SYS_RAWIO */
+	do_exit += check_for_cap_sys_rawio();
+
 	/* test file permissions */
 	sprintf(pathname, "/dev/cpu/%d/msr", base_cpu);
 	if (euidaccess(pathname, R_OK)) {