Francesco Ruggeri
024a8168b7
We observed two panics involving races with igb_reset_task. The first panic is caused by this race condition: kworker reboot -f igb_reset_task igb_reinit_locked igb_down napi_synchronize __igb_shutdown igb_clear_interrupt_scheme igb_free_q_vectors igb_free_q_vector adapter->q_vector[v_idx] = NULL; napi_disable Panics trying to access adapter->q_vector[v_idx].napi_state The second panic (a divide error) is caused by this race: kworker reboot -f tx packet igb_reset_task __igb_shutdown rtnl_lock() ... igb_clear_interrupt_scheme igb_free_q_vectors adapter->num_tx_queues = 0 ... rtnl_unlock() rtnl_lock() igb_reinit_locked igb_down igb_up netif_tx_start_all_queues dev_hard_start_xmit igb_xmit_frame igb_tx_queue_mapping Panics on r_idx % adapter->num_tx_queues This commit applies to igb_reset_task the same changes that were applied to ixgbe in commit2f90b8657e("ixgbe: this patch adds support for DCB to the kernel and ixgbe driver"), commit8f4c5c9fb8("ixgbe: reinit_locked() should be called with rtnl_lock") and commit88adce4ea8("ixgbe: fix possible race in reset subtask"). Signed-off-by: Francesco Ruggeri <fruggeri@arista.com> Tested-by: Aaron Brown <aaron.f.brown@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.