ice: rebuild ring stats arrays instead of reallocating them in place

ice_vsi_realloc_stat_arrays() resized the ring stats arrays in place
with krealloc_array(), sizing them from vsi->req_txq/req_rxq. That is
not what ice_vsi_set_num_qs() computes later in ice_vsi_cfg_def(), so
after a rebuild the arrays could end up shorter than vsi->alloc_txq /
vsi->alloc_rxq, and ice_vsi_alloc_ring_stats() then walked past their
end.

The VF case shows the divergence. ice_sriov_set_msix_vec_count() writes
vsi->req_txq and then calls ice_vsi_rebuild(), so the old resizer sized
from req_txq, while ice_vsi_get_num_qs() reads vf->num_req_qs ?:
vf->num_vf_qs and ignores req_txq entirely. Once a guest has raised
vf->num_req_qs through VIRTCHNL_OP_REQUEST_QUEUES the two disagree and
the arrays come out shorter than the alloc_txq/alloc_rxq the rebuild
installs. The reset that such a request triggers is a different path,
ice_vf_reconfig_vsi(), which does not use this resizer at all; that one
is handled by the next patch.

Replace it with ice_vsi_resize_stat_arrays(), which allocates a fresh
struct ice_vsi_stats instead, sized with ice_vsi_get_num_qs() and the
queues ice_vsi_decfg() is about to return to the PF pool, which is
exactly what ice_vsi_set_num_qs() will compute once they are back
there, barring a concurrent change of the PF pool; the next patch stops
relying on that. Copy the surviving entry pointers over and install
the new structure, all before ice_vsi_decfg() runs. The entries that
did not fit are freed by ice_vsi_free_unused_stat_arrays(); the old
container itself then goes through __ice_vsi_free_stats() with
@free_entries set to false, since the entries it still points at now
belong to the new structure.

Allocating up front also means a failure no longer leaves a half-updated
ice_vsi_stats behind, with the Tx array already swapped and its surplus
Tx entries already freed, but the Rx allocation failed.

Put the allocate-install-free-surplus sequence in
ice_vsi_install_stat_arrays(), next to ice_vsi_new_stat_arrays(), so
that only the sizing decision is left in the resizer.

Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Link: https://patch.msgid.link/20260925132636.123300-6-przemyslaw.kitszel@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Przemek Kitszel 2026-09-25 15:15:47 +02:00 • committed by Jakub Kicinski
commit 66444f06a9