Fix zfs_arc_max minimum tuning

When setting `zfs_arc_max` its minimum value is allowed
to be 64 MiB.  There was an off-by-1 error which can matter
on tiny systems.

Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Zubrzycki <github@mid-earth.net>
Closes #7417

diff --git a/module/zfs/arc.c b/module/zfs/arc.c
index 40a93107d9c0e7bcbe4237912c5bb908a42d2057..d73d6ffcc1e6cf0af5de91a793ea33e446de0335 100644 (file)
--- a/module/zfs/arc.c
+++ b/module/zfs/arc.c
@@ -7282,7 +7282,7 @@ arc_tuning_update(void)
 
        /* Valid range: 64M - <all physical memory> */
        if ((zfs_arc_max) && (zfs_arc_max != arc_c_max) &&
-           (zfs_arc_max > 64 << 20) && (zfs_arc_max < allmem) &&
+           (zfs_arc_max >= 64 << 20) && (zfs_arc_max < allmem) &&
            (zfs_arc_max > arc_c_min)) {
                arc_c_max = zfs_arc_max;
                arc_c = arc_c_max;