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From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org,
	stable@vger.kernel.org
Cc: Len Brown <len.brown@intel.com>,
	Sasha Levin <sashal@kernel.org>,
	lenb@kernel.org,
	linux-pm@vger.kernel.org
Subject: [PATCH AUTOSEL 6.8 07/43] tools/power turbostat: Fix warning upon failed /dev/cpu_dma_latency read
Date: Mon, 22 Apr 2024 19:13:53 -0400
Message-ID: <20240422231521.1592991-7-sashal@kernel.org>
In-Reply-To: <20240422231521.1592991-1-sashal@kernel.org>
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From: Len Brown <len.brown@intel.com>

[ Upstream commit b6fe938317eed58e8c687bd5965a956e15fb5828 ]

Previously a failed read of /dev/cpu_dma_latency erroneously complained
turbostat: capget(CAP_SYS_ADMIN) failed, try "# setcap cap_sys_admin=ep ./turbostat

This went unnoticed because this file is typically visible to root,
and turbostat was typically run as root.

Going forward, when a non-root user can run turbostat...
Complain about failed read access to this file only if --debug is used.

Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/power/x86/turbostat/turbostat.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index a4a40a6e1b957..3438ad938d7e4 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -5545,7 +5545,8 @@ void print_dev_latency(void)
 
 	fd = open(path, O_RDONLY);
 	if (fd < 0) {
-		warnx("capget(CAP_SYS_ADMIN) failed, try \"# setcap cap_sys_admin=ep %s\"", progname);
+		if (debug)
+			warnx("Read %s failed", path);
 		return;
 	}
 
-- 
2.43.0