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| author | Yisheng Xie <xieyisheng1@huawei.com> | 2018-01-31 16:16:15 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-01-31 17:18:36 -0800 |
| commit | 0486a38bcc4749808edbc848f1bcf232042770fc (patch) | |
| tree | 086609c0e0916a43469e57d4ae6f2ba51ce34c06 /mm/mempolicy.c | |
| parent | 56521e7a02b7b84a5e72691a1fb15570e6055545 (diff) | |
| download | lwn-0486a38bcc4749808edbc848f1bcf232042770fc.tar.gz lwn-0486a38bcc4749808edbc848f1bcf232042770fc.zip | |
mm/mempolicy: add nodes_empty check in SYSC_migrate_pages
As in manpage of migrate_pages, the errno should be set to EINVAL when
none of the node IDs specified by new_nodes are on-line and allowed by
the process's current cpuset context, or none of the specified nodes
contain memory. However, when test by following case:
new_nodes = 0;
old_nodes = 0xf;
ret = migrate_pages(pid, old_nodes, new_nodes, MAX);
The ret will be 0 and no errno is set. As the new_nodes is empty, we
should expect EINVAL as documented.
To fix the case like above, this patch check whether target nodes AND
current task_nodes is empty, and then check whether AND
node_states[N_MEMORY] is empty.
Link: http://lkml.kernel.org/r/1510882624-44342-4-git-send-email-xieyisheng1@huawei.com
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Chris Salls <salls@cs.ucsb.edu>
Cc: Christopher Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Tan Xiaojun <tanxiaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/mempolicy.c')
| -rw-r--r-- | mm/mempolicy.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 65df28d7cc89..f604b22ebb65 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1433,10 +1433,14 @@ SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned long, maxnode, goto out_put; } - if (!nodes_subset(*new, node_states[N_MEMORY])) { - err = -EINVAL; + task_nodes = cpuset_mems_allowed(current); + nodes_and(*new, *new, task_nodes); + if (nodes_empty(*new)) + goto out_put; + + nodes_and(*new, *new, node_states[N_MEMORY]); + if (nodes_empty(*new)) goto out_put; - } err = security_task_movememory(task); if (err) |