From 2481f6302d65f98d143aca9933a0fd17b492069a Mon Sep 17 00:00:00 2001
From: Michal Privoznik <mprivozn@redhat.com>
Date: Fri, 11 Sep 2020 11:50:33 +0200
Subject: [PATCH 096/108] virnuma: Use numa_nodes_ptr when checking available
 NUMA nodes
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In v6.7.0-rc1~86 I've tried to fix a problem where we were not
detecting NUMA nodes properly because we misused behaviour of a
libnuma API and as it turned out the behaviour was correct for
hosts with 64 CPUs in one NUMA node. So I changed the code to use
nodemask_isset(&numa_all_nodes, ..) instead and it fixed the
problem on such hosts. However, what I did not realize is that
numa_all_nodes does not reflect all NUMA nodes visible to
userspace, it contains only those nodes that the process
(libvirtd) an allocate memory from, which can be only a subset of
all NUMA nodes. The bitmask that contains all NUMA nodes visible
to userspace and which one I should have used is: numa_nodes_ptr.
For curious ones:

https://github.com/numactl/numactl/commit/4a22f2238234155e11e3e2717c011864722b767b

And as I was fixing virNumaGetNodeCPUs() I came to realize that
we already have a function that wraps the correct bitmask:
virNumaNodeIsAvailable().

Fixes: 24d7d85208f812a45686b32a0561cc9c5c9a49c9
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1876956
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
(cherry picked from commit 551fb778f5451d40211867365b5eb9b8384b4e3b)
---
 src/util/virnuma.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/util/virnuma.c b/src/util/virnuma.c
index 75d5628cff..b7e6473e77 100644
--- a/src/util/virnuma.c
+++ b/src/util/virnuma.c
@@ -260,7 +260,7 @@ virNumaGetNodeCPUs(int node,
 
     *cpus = NULL;
 
-    if (!nodemask_isset(&numa_all_nodes, node)) {
+    if (!virNumaNodeIsAvailable(node)) {
         VIR_DEBUG("NUMA topology for cell %d is not available, ignoring", node);
         return -2;
     }
-- 
2.33.0