From 717d1c2ee31e28af834278e0ace4b48f086c3c6a Mon Sep 17 00:00:00 2001 From: "Christopher J. Morrone" Date: Sun, 27 Apr 2014 13:06:48 -0400 Subject: [PATCH] staging/lustre/llite: Avoid statahead thread start/stop deadlocks The statahead and statahead agl threads blindly set their thread state to SVC_RUNNING without checking the state first. If, for instance, another thread sets the state to SVC_STOPPING that stop signal will now have been lost. Deadlock ensues. We also partly improve the sai reference counting, because a race exists where the ll_stop_statahead thread can drop the default reference, and the statahead thread can exit and drop its reference as well. With no references on the sai, the final put will poison and free the buffer. The original do_statahead_enter() function may then continue to access the buffer after it is freed because it did not take a reference of its own. We add a local reference to address that. Signed-off-by: Christopher J. Morrone Reviewed-on: http://review.whamcloud.com/9358 Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4624 Reviewed-by: Lai Siyao Reviewed-by: Fan Yong Signed-off-by: Oleg Drokin Signed-off-by: Greg Kroah-Hartman --- Reading git-format-patch failed