[tip: refs/heads/x86/mm] x86/mm: Fix cpumask_of_node() error condition

[tip-bot2 for Peter Zijlstra]

The following commit has been merged into the refs/heads/x86/mm branch of tip:

Commit-ID:     bc04a049f058a472695aa22905d57e2b1f4c77d9
Gitweb:        https://git.kernel.org/tip/bc04a049f058a472695aa22905d57e2b1f4c77d9
Author:        Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate:    Tue, 03 Sep 2019 09:53:52 +02:00
Committer:     Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Thu, 05 Sep 2019 13:03:04 +02:00

x86/mm: Fix cpumask_of_node() error condition

When CONFIG_DEBUG_PER_CPU_MAPS=y we validate that the @node argument of
cpumask_of_node() is a valid node_id. It however forgets to check for
negative numbers. Fix this by explicitly casting to unsigned int.

  (unsigned)node >= nr_node_ids

verifies: 0 <= node < nr_node_ids

Also ammend the error message to match the condition.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Yunsheng Lin <linyunsheng@xxxxxxxxxx>
Link: https://lkml.kernel.org/r/20190903075352.GY2369@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 arch/x86/mm/numa.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
index e6dad60..4123100 100644
--- a/arch/x86/mm/numa.c
+++ b/arch/x86/mm/numa.c
@@ -861,9 +861,9 @@ void numa_remove_cpu(int cpu)
  */
 const struct cpumask *cpumask_of_node(int node)
 {
-	if (node >= nr_node_ids) {
+	if ((unsigned)node >= nr_node_ids) {
 		printk(KERN_WARNING
-			"cpumask_of_node(%d): node > nr_node_ids(%u)\n",
+			"cpumask_of_node(%d): (unsigned)node >= nr_node_ids(%u)\n",
 			node, nr_node_ids);
 		dump_stack();
 		return cpu_none_mask;