Messages in this thread | | | From | Andy Lutomirski <> | Date | Wed, 20 May 2020 10:13:02 -0700 | Subject | Re: [patch V6 36/37] x86/entry: Move paranoid irq tracing out of ASM code |
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On Wed, May 20, 2020 at 8:17 AM Thomas Gleixner <tglx@linutronix.de> wrote: > > Andy Lutomirski <luto@kernel.org> writes: > > > On Fri, May 15, 2020 at 5:11 PM Thomas Gleixner <tglx@linutronix.de> wrote: > > > > I think something's missing here. With this patch applied, don't we > > get to exc_debug_kernel() -> handle_debug() without doing > > idtentry_enter() or equivalent? And that can even enable IRQs. > > > > Maybe exc_debug_kernel() should wrap handle_debug() in some > > appropriate _enter() / _exit() pair? > > I'm the one who is missing something here, i.e. the connection of this > patch to #DB. exc_debug_kernel() still looks like this: > > nmi_enter_notrace(); > handle_debug(regs, dr6, false); > nmi_exit_notrace(); > > Confused. >
Hmm. I guess the code is correct-ish or at least as correct as it ever was. But $SUBJECT says "Move paranoid irq tracing out of ASM code" but you didn't move it into all the users. So now the NMI code does trace_hardirqs_on_prepare() but the #DB code doesn't. Perhaps the changelog should mention this.
exc_kernel_debug() is an atrocity. Every now and then I get started on cleanup it up and so far I always get mired in the giant amount of indirection.
So Acked-by: Andy Lutomirski <luto@kernel.org> if you write a credible changelog.
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