diff options
| -rw-r--r-- | arch/arm/mm/alignment.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c index d073b64ae87..724ba3bce72 100644 --- a/arch/arm/mm/alignment.c +++ b/arch/arm/mm/alignment.c @@ -885,8 +885,23 @@ do_alignment(unsigned long addr, unsigned int fsr, struct pt_regs *regs) if (ai_usermode & UM_SIGNAL) force_sig(SIGBUS, current); - else - set_cr(cr_no_alignment); + else { + /* + * We're about to disable the alignment trap and return to + * user space. But if an interrupt occurs before actually + * reaching user space, then the IRQ vector entry code will + * notice that we were still in kernel space and therefore + * the alignment trap won't be re-enabled in that case as it + * is presumed to be always on from kernel space. + * Let's prevent that race by disabling interrupts here (they + * are disabled on the way back to user space anyway in + * entry-common.S) and disable the alignment trap only if + * there is no work pending for this thread. + */ + raw_local_irq_disable(); + if (!(current_thread_info()->flags & _TIF_WORK_MASK)) + set_cr(cr_no_alignment); + } return 0; } |