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Subject: Re: [PATCH] kdb: Change timespec to use timespec64
To: Daniel Thompson <daniel.thompson@linaro.org>,
        Baolin Wang <baolin.wang@linaro.org>
CC: Arnd Bergmann <arnd@arndb.de>, Ingo Molnar <mingo@kernel.org>,
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From: Jason Wessel <jason.wessel@windriver.com>
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Date: Thu, 25 Jan 2018 08:49:02 -0600
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On 01/25/2018 05:38 AM, Daniel Thompson wrote:
> On Thu, Jan 25, 2018 at 05:18:54PM +0800, Baolin Wang wrote:
>> On 25 January 2018 at 16:55, Arnd Bergmann <arnd@arndb.de> wrote:
>>> On Thu, Jan 25, 2018 at 9:05 AM, Baolin Wang <baolin.wang@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?
> 
> 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!
> 
> 

I thought for what ever reason this was going through the time keeper subtree.   I added it immediately to kgdb-next so it will be evaluated in the linux-next tree in the next day or so, and we can get this merged in the merge window.

Thanks,
Jason.