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

From: Jason Wessel
Date: Thu Jan 25 2018 - 09:49:23 EST


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@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!



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.