The critical section cleanup code misses to add the offset of the
thread_struct to the task address.
Therefore, if the critical section code gets executed, it may corrupt
the task struct or restore the contents of the floating point registers
from the wrong memory location.
Fixes
d0164ee20d "s390/kernel: remove save_fpu_regs() parameter and use
__LC_CURRENT instead".
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
clg %r9,BASED(.Lcleanup_save_fpu_fpc_end)
jhe 1f
lg %r2,__LC_CURRENT
+ aghi %r2,__TASK_thread
0: # Store floating-point controls
stfpc __THREAD_FPU_fpc(%r2)
1: # Load register save area and check if VX is active
clg %r9,BASED(.Lcleanup_load_fpu_regs_vx_ctl)
jhe 6f
lg %r4,__LC_CURRENT
+ aghi %r4,__TASK_thread
lfpc __THREAD_FPU_fpc(%r4)
tm __THREAD_FPU_flags+3(%r4),FPU_USE_VX # VX-enabled task ?
lg %r4,__THREAD_FPU_regs(%r4) # %r4 <- reg save area