On 25 January 2018 at 16:55, Arnd Bergmann <a...@arndb.de> wrote:
> On Thu, Jan 25, 2018 at 9:05 AM, Baolin Wang <baolin.w...@linaro.org> 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?
>
>> @@ -2521,8 +2521,8 @@ static void kdb_gmtime(struct timespec *tv, struct
>> kdb_tm *tm)
>> */
>> static void kdb_sysinfo(struct sysinfo *val)
>> {
>> - struct timespec uptime;
>> - ktime_get_ts(&uptime);
>> + struct timespec64 uptime;
>> + ktime_get_ts64(&uptime);
>> memset(val, 0, sizeof(*val));
>> val->uptime = uptime.tv_sec;
>> val->loads[0] = avenrun[0];
>
> This function appears to have the same problem, except that it is a
> preexisting
> issue in this case. I had not noticed this earlier, but we must fix it
> in a similar
> manner to the other one.
OK.
--
Baolin.wang
Best Regards
