[PATCH 1/3] arm64/numa: set numa_off to false when numa node is fake

From: Jia He <justin.he@arm.com>
To: Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Mike Rapoport <rppt@linux.ibm.com>, Baoquan He <bhe@redhat.com>,
	Chuhong Yuan <hslester96@gmail.com>,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	Kaly Xin <Kaly.Xin@arm.com>, Jia He <justin.he@arm.com>
Subject: [PATCH 1/3] arm64/numa: set numa_off to false when numa node is fake
Date: Mon,  6 Jul 2020 09:19:45 +0800	[thread overview]
Message-ID: <20200706011947.184166-2-justin.he@arm.com> (raw)
In-Reply-To: <20200706011947.184166-1-justin.he@arm.com>

Previously, numa_off is set to true unconditionally in dummy_numa_init(),
even if there is a fake numa node.

But acpi will translate node id to NUMA_NO_NODE(-1) in acpi_map_pxm_to_node()
because it regards numa_off as turning off the numa node.

Without this patch, pmem can't be probed as a RAM device on arm64 if SRAT table
isn't present.

$ndctl create-namespace -fe namespace0.0 --mode=devdax --map=dev -s 1g -a 64K
kmem dax0.0: rejecting DAX region [mem 0x240400000-0x2bfffffff] with invalid node: -1
kmem: probe of dax0.0 failed with error -22

This fixes it by setting numa_off to false.

Signed-off-by: Jia He <justin.he@arm.com>
---
 arch/arm64/mm/numa.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
index aafcee3e3f7e..7689986020d9 100644
--- a/arch/arm64/mm/numa.c
+++ b/arch/arm64/mm/numa.c
@@ -440,7 +440,8 @@ static int __init dummy_numa_init(void)
 		return ret;
 	}
 
-	numa_off = true;
+	/* force numa_off to be false since we have a fake numa node here */
+	numa_off = false;
 	return 0;
 }
 
-- 
2.17.1

