This patch applies to 5.9 and earlier kernels only.

Since 5.10, this has been fortunately fixed by the commit e5e179aa3a39 ("pseries/drmem: don't cache node id in drmem_lmb struct").

When LMBs are added to a running system, the node id assigned to the LMB is fetched from the temporary DT node provided by the hypervisor.

However, LMBs added are always assigned to the first online node. This is a mistake and this is because hot_add_drconf_scn_to_nid() called by lmb_set_nid() is checking for the LMB flags DRCONF_MEM_ASSIGNED which is set later in dlpar_add_lmb().

To fix this issue, simply set that flag earlier in dlpar_add_lmb().

Note, this code has been rewrote in 5.10 and thus this fix has no meaning since this version.

Signed-off-by: Laurent Dufour ldufour@linux.ibm.com Cc: Michael Ellerman mpe@ellerman.id.au Cc: Benjamin Herrenschmidt benh@kernel.crashing.org Cc: Paul Mackerras paulus@samba.org Cc: Nathan Lynch nathanl@linux.ibm.com Cc: Scott Cheloha cheloha@linux.ibm.com Cc: linuxppc-dev@lists.ozlabs.org Cc: stable@vger.kernel.org --- arch/powerpc/platforms/pseries/hotplug-memory.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c index e54dcbd04b2f..92d83915c629 100644 --- a/arch/powerpc/platforms/pseries/hotplug-memory.c +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c @@ -663,12 +663,14 @@ static int dlpar_add_lmb(struct drmem_lmb *lmb) return rc; }

+ lmb->flags |= DRCONF_MEM_ASSIGNED; lmb_set_nid(lmb); block_sz = memory_block_size_bytes();

/* Add the memory */ rc = __add_memory(lmb->nid, lmb->base_addr, block_sz); if (rc) { + lmb->flags &= ~DRCONF_MEM_ASSIGNED; invalidate_lmb_associativity_index(lmb); return rc; } @@ -676,10 +678,9 @@ static int dlpar_add_lmb(struct drmem_lmb *lmb) rc = dlpar_online_lmb(lmb); if (rc) { __remove_memory(lmb->nid, lmb->base_addr, block_sz); + lmb->flags &= ~DRCONF_MEM_ASSIGNED; invalidate_lmb_associativity_index(lmb); lmb_clear_nid(lmb); - } else { - lmb->flags |= DRCONF_MEM_ASSIGNED; }

return rc;