lscpu: avoid len = 0 as a consequence of maxcpus = 0

This problem was observed on an x86_64 Mobile AMD Sempron 3700+ where kernel_max
returned "0" as the index of the highest CPU.

As a consequence, several variables in lscpu, which relied on maxcpus >= 1 (in
particular the 'len' value) were set to 0, resulting in the following errors:

host>./lscpu
lscpu: failed to read: /sys/devices/system/cpu/online: No such file or directory
host> cat /sys/devices/system/cpu/kernel_max
0

The fix used by this patch is to interpret kernel_max as an index and maxcpus as
a count >= 1, tested to work.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/sys-utils/lscpu.c b/sys-utils/lscpu.c
index ca2adb86492ccb11846fad7899cc7e01b52e8e34..224d5f99bf84918fc5f9120c9ff6324548b9a23d 100644 (file)
--- a/sys-utils/lscpu.c
+++ b/sys-utils/lscpu.c
@@ -392,7 +392,8 @@ read_basicinfo(struct lscpu_desc *desc)
        fclose(fp);
 
        if (path_exist(_PATH_SYS_SYSTEM "/cpu/kernel_max"))
-               maxcpus = path_getnum(_PATH_SYS_SYSTEM "/cpu/kernel_max");
+               /* note that kernel_max is maximum index [NR_CPUS-1] */
+               maxcpus = path_getnum(_PATH_SYS_SYSTEM "/cpu/kernel_max") + 1;
 
        else if (!sysrootlen)
                /* the root is '/' so we are working with data from the current kernel */