[RFC Patch V1 11/30] mm, char/mspec.c: Use cpu_to_mem()/numa_mem_id() to support memoryless node

Jiang Liu <[email protected]> Fri, 11 Jul 2014 07:37:28 +0000
Newsgroups org.kernel.vger.linux-hotplug,org.kernel.vger.linux-kernel,org.kvack.linux-mm
Message-ID <[email protected]>
When CONFIG_HAVE_MEMORYLESS_NODES is enabled, cpu_to_node()/numa_node_id()
may return a node without memory, and later cause system failure/panic
when calling kmalloc_node() and friends with returned node id.
So use cpu_to_mem()/numa_mem_id() instead to get the nearest node with
memory for the/current cpu.

If CONFIG_HAVE_MEMORYLESS_NODES is disabled, cpu_to_mem()/numa_mem_id()
is the same as cpu_to_node()/numa_node_id().

Signed-off-by: Jiang Liu <[email protected]>
---
 drivers/char/mspec.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/char/mspec.c b/drivers/char/mspec.c
index f1d7fa45c275..20e893cde9fd 100644
--- a/drivers/char/mspec.c
+++ b/drivers/char/mspec.c
@@ -206,7 +206,7 @@ mspec_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 
 	maddr = (volatile unsigned long) vdata->maddr[index];
 	if (maddr = 0) {
-		maddr = uncached_alloc_page(numa_node_id(), 1);
+		maddr = uncached_alloc_page(numa_mem_id(), 1);
 		if (maddr = 0)
 			return VM_FAULT_OOM;
 
-- 
1.7.10.4