DragonFly commits List (threaded) for 2011-02
git: kernel - Fix list corruption in dsched
Author: Matthew Dillon <email@example.com>
Date: Sat Feb 12 13:30:16 2011 -0800
kernel - Fix list corruption in dsched
* dsched_thread_ctx_alloc() was not acquiring the global lock across
calls to dsched_thread_io_alloc(), creating a race condition in the
call to TAILQ_INSERT_TAIL(&tdio->diskctx->tdio_list, ...).
This case can occur under heavy fork/exit loads, particularly when
(soon) fork and exit get out from the MP lock, but even with the MP
lock on the frontend it can occur against the dsched backend.
* dsched_new_policy_thread_tdio() was not acquiring the global lock
across its initial call to dsched_thread_io_alloc(). This case could
only occur with extreme rarity.
Summary of changes:
sys/kern/kern_dsched.c | 9 ++++++---
1 files changed, 6 insertions(+), 3 deletions(-)
DragonFly BSD source repository