Date: Fri, 19 Nov 2021 08:02:23 UTC
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=259458 --- Comment #20 from commit-hook@FreeBSD.org --- A commit in branch main references this bug: URL: https://cgit.FreeBSD.org/src/commit/?id=1bfdb812c786ac2607a82633f9c84a5d16f54079 commit 1bfdb812c786ac2607a82633f9c84a5d16f54079 Author: Andriy Gapon <avg@FreeBSD.org> AuthorDate: 2021-11-19 07:56:30 +0000 Commit: Andriy Gapon <avg@FreeBSD.org> CommitDate: 2021-11-19 08:00:38 +0000 iflib_stop: drain rx tasks to prevent any data races iflib_stop modifies iflib data structures that are used by _task_fn_rx, most prominently the free lists. So, iflib_stop has to ensure that the rx task threads are not active. This should help to fix a crash seen when iflib_if_ioctl (e.g., SIOCSIFCAP) is called while there is already traffic flowing. The crash has been seen on VMWare guests with vmxnet3 driver. My guess is that on physical hardware the couple of 1ms delays that iflib_stop has after disabling interrupts are enough for the queued work to be completed before any iflib state is touched. But on busy hypervisors the guests might not get enough CPU time to complete the work, thus there can be a race between the taskqueue threads and the work done to handle an ioctl, specifically in iflib_stop and iflib_init_locked. PR: 259458 Reviewed by: markj MFC after: 3 weeks Differential Revision: https://reviews.freebsd.org/D32926 sys/net/iflib.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) -- You are receiving this mail because: You are the assignee for the bug.