[PATCH iwl-net v4 0/6] ice: fix synchronization between .ndo_bpf() and reset

Larysa Zaremba
2024-08-23T10:07:58Z

PF reset can be triggered asynchronously, by tx_timeout or by a user. With some
unfortunate timings both ice_vsi_rebuild() and .ndo_bpf will try to access and
modify XDP rings at the same time, causing system crash.

The first patch factors out rtnl-locked code from VSI rebuild code to avoid
deadlock. The following changes lock rebuild and .ndo_bpf() critical sections
with an internal mutex as well and provide complementary fixes.

v3: https://lore.kernel.org/netdev/20240819100606.15383-1-larysa.zaremba@intel.com/
v3->v4:
* fix kdoc and add an additional "Fixes:" tag in the first patch
* clear rebuild pending flag only when ice_vsi_rebuild completes successfully
* remove the deadlock part from the commit message in the fifth patch,
this particular aspect was recently fixed in another patch
* update tags

v2: https://lore.kernel.org/netdev/20240724164840.2536605-1-larysa.zaremba@intel.com/
v2->v3:
* deconfig VSI when coalesce allocation fails in ice_vsi_rebuild (patch 2/6)
* rebase and resolve conflicts in patch 3 and 4
* add tags from v2

v1: https://lore.kernel.org/netdev/20240610153716.31493-1-larysa.zaremba@intel.com/
v1->v2:
* use mutex for locking
* redefine critical sections
* account for short time between rebuild and VSI being open
* add netif_queue_set_napi() patch, so ICE_RTNL_WAITS_FOR_RESET strategy can be
dropped, no more rtnl-locked code in ice_vsi_rebuild()
* change the test case from waiting for tx_timeout to happen to actively firing
resets through sysfs, this adds more minor fixes on top

Larysa Zaremba (6):
ice: move netif_queue_set_napi to rtnl-protected sections
ice: protect XDP configuration with a mutex
ice: check for XDP rings instead of bpf program when unconfiguring
ice: check ICE_VSI_DOWN under rtnl_lock when preparing for reset
ice: remove ICE_CFG_BUSY locking from AF_XDP code
ice: do not bring the VSI up, if it was down before the XDP setup

drivers/net/ethernet/intel/ice/ice.h | 2 +
drivers/net/ethernet/intel/ice/ice_base.c | 11 +-
drivers/net/ethernet/intel/ice/ice_lib.c | 179 ++++++++--------------
drivers/net/ethernet/intel/ice/ice_lib.h | 10 +-
drivers/net/ethernet/intel/ice/ice_main.c | 47 ++++--
drivers/net/ethernet/intel/ice/ice_xsk.c | 18 +--
6 files changed, 106 insertions(+), 161 deletions(-)

--
2.43.0