Re: [PATCH] kdb: Change timespec to use timespec64

From: Daniel Thompson
Date: Thu Jan 25 2018 - 06:38:17 EST


On Thu, Jan 25, 2018 at 05:18:54PM +0800, Baolin Wang wrote:
> On 25 January 2018 at 16:55, Arnd Bergmann <arnd@xxxxxxxx> wrote:
> > On Thu, Jan 25, 2018 at 9:05 AM, Baolin Wang <baolin.wang@xxxxxxxxxx> wrote:
> >> @@ -2554,7 +2554,7 @@ static int kdb_summary(int argc, const char **argv)
> >> kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
> >> kdb_printf("ccversion %s\n", __stringify(CCVERSION));
> >>
> >> - now = __current_kernel_time();
> >> + now = current_kernel_time64();
> >> kdb_gmtime(&now, &tm);
> >> kdb_printf("date %04d-%02d-%02d %02d:%02d:%02d "
> >> "tz_minuteswest %d\n",
> >
> > Thanks for picking this one up again, we should find a permanent solution here.
> > Unfortunately you patch is incorrect, as we cannot safely call
> > current_kernel_time64()
> > from NMI context.
>
> Ah, thanks for pointing out the issue, since I do not know what
> context the function will be called in kdb.
>
> >
> > The __ prefix on __current_kernel_time() indicates that this is a special call
> > that intentionally doesn't read the hardware time to avoid taking locks that
> > might already be held in the context from which we entered the debugger.
> >
> > See https://patchwork.kernel.org/patch/10002097/ for my earlier patch.
>
> This patch had not been merged into mainline?

Not yet (and I'm afraid it's not in kgdb-next either) but the ack from Jason is from
this kernel cycle so we'll see what can be done!


Daniel.