This series aims to remedy an issue that not all per-arch versions of
cpumask_of_node() are robust against NUMA_NO_NODE.
In my view, cpumask_of_node() should be able to handle NUMA_NO_NODE. This
is because NUMA_NO_NODE is a valid index from the following flow, where
the device NUMA node is not set (from default):
device_initialize(dev)
set_dev_node(dev, NUMA_NO_NODE);
mask = cpumask_of_node(dev_to_node(dev));
The CONFIG_DEBUG_PER_CPU_MAPS=n x86 version cpumask_of_node() would
produce an array out-of-index issue (when passed NUMA_NO_NODE), which I
think is attempted to be worked around here:
https://lore.kernel.org/linux-scsi/cf0f9085-6c87-4dd5-9114-925723e68495@oracle.com/T/#mdedb68052e419b4bfca9ce45bb33b58988018945
I also see a CVE which also looks related:
https://nvd.nist.gov/vuln/detail/cve-2024-39277
Each per-arch version could be picked up separately, as can the
asm-generic change.
John Garry (4):
include/asm-generic/topology.h: Remove unused definition of
cpumask_of_node()
LoongArch: Make cpumask_of_node() robust against NUMA_NO_NODE
MIPS: Loongson: Make cpumask_of_node() robust against NUMA_NO_NODE
x86/cpu/topology: Make cpumask_of_node() robust against NUMA_NO_NODE
arch/loongarch/include/asm/topology.h | 4 +++-
arch/mips/include/asm/mach-loongson64/topology.h | 4 +++-
arch/x86/include/asm/topology.h | 2 ++
arch/x86/mm/numa.c | 2 ++
include/asm-generic/topology.h | 8 ++------
5 files changed, 12 insertions(+), 8 deletions(-)
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2.43.5