On Wed, Feb 06, 2008 at 11:00:01PM +0100, Ingo Molnar wrote: > > * Neil Horman <[EMAIL PROTECTED]> wrote: > > > if (!user_mode_vm(regs)) { > > + nmi_exit(); > > + local_irq_enable(); > > current->thread.trap_no = 2; > > crash_kexec(regs); > > looks good to me, but please move the local_irq_enable() to within > crash_kexec() instead - probably inside the "got the kexec lock" > section. That makes crash_kexec() use generally safer too i guess: right > it seems that die() too can call crash_kexec() with irqs disabled - and > can thus hang in smp_send_stop() [or wherever it hung before]. >
In general, I think we should not be servicing interrupts once the system has crashed and crash_kexec() has been invoked. In fact, right now machine_crash_shutdown() explicity disables interrupt before sending NMIs to other cpus to stop these cpus and which makes sense to me. I am wondering if interrupts are disabled on crashing cpu or if crashing cpu is inside die_nmi(), how would it stop/prevent delivery of NMI IPI to other cpus. Am I missing something obivious? Thanks Vivek -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/