Hi Mike,

Sorry for reviving a rather old thread.

On Wed, 07 Aug 2024 07:41:08 +0100,
Mike Rapoport [off-list ref] wrote:

From: "Mike Rapoport (Microsoft)" <rppt@kernel.org>

Until now arch_numa was directly translating firmware NUMA information
to memblock.

Using numa_memblks as an intermediate step has a few advantages:
* alignment with more battle tested x86 implementation
* availability of NUMA emulation
* maintaining node information for not yet populated memory

Adjust a few places in numa_memblks to compile with 32-bit phys_addr_t
and replace current functionality related to numa_add_memblk() and
__node_distance() in arch_numa with the implementation based on
numa_memblks and add functions required by numa_emulation.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Tested-by: Zi Yan <ziy@nvidia.com> # for x86_64 and arm64
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> [arm64 + CXL via QEMU]
Acked-by: Dan Williams <redacted>
Acked-by: David Hildenbrand <redacted>
---
 drivers/base/Kconfig       |   1 +
 drivers/base/arch_numa.c   | 201 +++++++++++--------------------------
 include/asm-generic/numa.h |   6 +-
 mm/numa_memblks.c          |  17 ++--
 4 files changed, 75 insertions(+), 150 deletions(-)

[...]

 static int __init numa_register_nodes(void)
 {
 	int nid;
-	struct memblock_region *mblk;
-
-	/* Check that valid nid is set to memblks */
-	for_each_mem_region(mblk) {
-		int mblk_nid = memblock_get_region_node(mblk);
-		phys_addr_t start = mblk->base;
-		phys_addr_t end = mblk->base + mblk->size - 1;
-
-		if (mblk_nid == NUMA_NO_NODE || mblk_nid >= MAX_NUMNODES) {
-			pr_warn("Warning: invalid memblk node %d [mem %pap-%pap]\n",
-				mblk_nid, &start, &end);
-			return -EINVAL;
-		}
-	}
 

This hunk has the unfortunate side effect of killing my ThunderX
extremely early at boot time, as this sorry excuse for a machine
really relies on the kernel recognising that whatever NUMA information
the FW offers is BS.

Reverting this hunk restores happiness (sort of).

FWIW, I've posted a patch with such revert at [1].

Thanks,

	M.

[1] https://lore.kernel.org/r/20241127193000.3702637-1-maz@kernel.org (local)

-- 
Without deviation from the norm, progress is not possible.