From d4490efed068a552e8b67d52a0726458a224c9a0 Mon Sep 17 00:00:00 2001 From: Frank Arnold Date: Wed, 8 Dec 2010 17:39:14 +0100 Subject: [PATCH 3/8] cpufrequtils aperf: Fix MSR read on 32-bit The cpufreq-aperf command does not work on 32-bit systems. The reason for that is a wrong count argument passed to the read() call. Instead of the buffer size, the size of the pointer to the buffer is used. On 64-bit systems this just happened to work, because we need to read an 8 byte value and a pointer has a size of 8 bytes on 64-bit. On 32-bit systems only 4 bytes are read, which then triggers the error path. Signed-off-by: Frank Arnold Reviewed-by: Thomas Renninger Signed-off-by: Dominik Brodowski --- utils/aperf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/utils/aperf.c b/utils/aperf.c index 1c64501..6302f5a 100644 --- a/utils/aperf.c +++ b/utils/aperf.c @@ -100,7 +100,7 @@ static int read_msr(int cpu, unsigned int idx, unsigned long long *val) return -1; if (lseek(fd, idx, SEEK_CUR) == -1) goto err; - if (read(fd, val, sizeof val) != sizeof *val) + if (read(fd, val, sizeof *val) != sizeof *val) goto err; close(fd); return 0; -- 1.7.10