From: Heiko Carstens <heiko.carstens@xxxxxxxxxx> If a machine check is pending and the external or I/O interrupt handler returns to userspace io_mcck_pending is going to call s390_handle_mcck. Before this happens a call to TRACE_IRQS_ON was already made since we know that we are going back to userspace and hence interrupts will be enabled. So there was an indication that interrupts are enabled while in reality they are still disabled. s390_handle_mcck will do a local_irq_save/restore pair and confuse lockdep which later complains about inconsistent irq tracing. To solve this just call trace_hardirqs_off before calling s390_handle_mcck and trace_hardirqs_on afterwards. Signed-off-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx> Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> --- arch/s390/kernel/entry.S | 6 ++++-- arch/s390/kernel/entry64.S | 6 ++++-- 2 files changed, 8 insertions(+), 4 deletions(-) Index: quilt-2.6/arch/s390/kernel/entry64.S =================================================================== --- quilt-2.6.orig/arch/s390/kernel/entry64.S +++ quilt-2.6/arch/s390/kernel/entry64.S @@ -611,8 +611,10 @@ io_work_loop: # _TIF_MCCK_PENDING is set, call handler # io_mcck_pending: - larl %r14,io_work_loop - jg s390_handle_mcck # TIF bit will be cleared by handler + TRACE_IRQS_OFF + brasl %r14,s390_handle_mcck # TIF bit will be cleared by handler + TRACE_IRQS_ON + j io_work_loop # # _TIF_NEED_RESCHED is set, call schedule Index: quilt-2.6/arch/s390/kernel/entry.S =================================================================== --- quilt-2.6.orig/arch/s390/kernel/entry.S +++ quilt-2.6/arch/s390/kernel/entry.S @@ -624,9 +624,11 @@ io_work_loop: # _TIF_MCCK_PENDING is set, call handler # io_mcck_pending: + TRACE_IRQS_OFF l %r1,BASED(.Ls390_handle_mcck) - la %r14,BASED(io_work_loop) - br %r1 # TIF bit will be cleared by handler + basr %r14,%r1 # TIF bit will be cleared by handler + TRACE_IRQS_ON + b BASED(io_work_loop) # # _TIF_NEED_RESCHED is set, call schedule -- blue skies, Martin. "Reality continues to ruin my life." - Calvin. - To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
