[IA64] Fix race condition in the rt_sigprocmask fastcall
authorChristoph Lameter <clameter@sgi.com>
Thu, 9 Jun 2005 19:29:00 +0000 (12:29 -0700)
committerTony Luck <tony.luck@intel.com>
Thu, 9 Jun 2005 20:04:30 +0000 (13:04 -0700)
commita2a64769d0d3cc0380b4b6ecdcb781a2f790a69e
tree387ee93cf8ee39ca64dd53380d1ea25a4f6134e7
parent1834cd9fd27763f4e55184e4138a19ba36620174
[IA64] Fix race condition in the rt_sigprocmask fastcall

current->blocked will be set to the value of current->thread_info->flags if the
cmpxchg to update thread_info->flags fails. For performance reasons the store into
current->blocked was placed in the cmpxchg loop. However, the cmpxchg overwrites the
register holding the value to be stored. In the rare case of a retry the value of
thread_info->flags will be written into current->blocked.

The fix is to use another register so that the register containing the current->blocked
value is not overwritten.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
arch/ia64/kernel/fsys.S