[PATCH 6.18 57/83] idpf: improve locking around idpf_vc_xn_push_free()

Greg Kroah-Hartman
2026-04-13T16:09:15Z

From: Emil Tantilov <emil.s.tantilov@intel.com>

commit d086fae65006368618104ba4c57779440eab2217 upstream.

Protect the set_bit() operation for the free_xn bitmask in
idpf_vc_xn_push_free(), to make the locking consistent with rest of the
code and avoid potential races in that logic.

Fixes: 34c21fa894a1 ("idpf: implement virtchnl transaction manager")
Cc: stable@vger.kernel.org
Reported-by: Ray Zhang <sgzhang@google.com>
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Samuel Salin <Samuel.salin@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/intel/idpf/idpf_virtchnl.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
@@ -399,7 +399,9 @@ static void idpf_vc_xn_push_free(struct
struct idpf_vc_xn *xn)
{
idpf_vc_xn_release_bufs(xn);
+ spin_lock_bh(&vcxn_mngr->xn_bm_lock);
set_bit(xn->idx, vcxn_mngr->free_xn_bm);
+ spin_unlock_bh(&vcxn_mngr->xn_bm_lock);
}

/**