From 9380cf5a884e237fc0e2571d5adf0b43bb4412c8 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Wed, 9 Sep 2015 13:15:00 +0200 Subject: [PATCH] s390: fix floating point register corruption 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 Reviewed-by: Hendrik Brueckner Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/entry.S | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S index 247b7aae4c6d..09b039d7983d 100644 --- a/arch/s390/kernel/entry.S +++ b/arch/s390/kernel/entry.S @@ -1191,6 +1191,7 @@ cleanup_critical: 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 @@ -1252,6 +1253,7 @@ cleanup_critical: 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 -- 2.30.2