Module Name: src
Committed By: knakahara
Date: Mon Sep 7 09:14:54 UTC 2020
Modified Files:
src/sys/dev/pci/ixgbe: ixgbe.c
Log Message:
Fix race between ixgbe_msix_admin() and ixgbe_handle_admin(), pointed out by
ozaki-r@n.o.
The race is caused by the following.
CPU#A processes workqueue, CPU#B processes admin interrupt.
(0) one of CPUs already calls ixgbe_schedule_admin_tasklet()
such as ixgbe_handle_timer()
(1) CPU#A: read adapter->task_requests
(2) CPU#B: set adapter->task_requests
(3) CPU#B: read(and try to set) adapter->admin_pending
but adapter->admin_pending is set, so does not
call workqueue_enqueue()
(4) CPU#A: clear adapter->admin_pending
that is, the tasks set by (2) is not processed as missfire workqueue by (3).
To generate a diff of this commit:
cvs rdiff -u -r1.257 -r1.258 src/sys/dev/pci/ixgbe/ixgbe.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
