Re: [tip: timers/ptp] KVM: arm64: Use ktime_get_snapshot_id() to retrieve CLOCK_BOOTTIME

[Nathan Chancellor <nathan@kernel.org>]

Hi Thomas,

On Tue, Jun 02, 2026 at 09:46:13AM -0000, tip-bot2 for Thomas Gleixner wrote:
> The following commit has been merged into the timers/ptp branch of tip:
> 
> Commit-ID:     d09439210441efbadd8b0aa32c1ddb1eab2f3abd
> Gitweb:        https://git.kernel.org/tip/d09439210441efbadd8b0aa32c1ddb1eab2f3abd
> Author:        Thomas Gleixner <tglx@kernel.org>
> AuthorDate:    Fri, 29 May 2026 22:00:08 +02:00
> Committer:     Thomas Gleixner <tglx@kernel.org>
> CommitterDate: Tue, 02 Jun 2026 11:39:58 +02:00
> 
> KVM: arm64: Use ktime_get_snapshot_id() to retrieve CLOCK_BOOTTIME
...
>  arch/arm64/kvm/hyp_trace.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/arm64/kvm/hyp_trace.c b/arch/arm64/kvm/hyp_trace.c
> index 8b7f2bf..b056c65 100644
> --- a/arch/arm64/kvm/hyp_trace.c
> +++ b/arch/arm64/kvm/hyp_trace.c
> @@ -51,8 +51,8 @@ static void __hyp_clock_work(struct work_struct *work)
>  
>  	hyp_clock = container_of(dwork, struct hyp_trace_clock, work);
>  
> -	ktime_get_snapshot(&snap);
> -	boot = ktime_to_ns(snap.boot);
> +	ktime_get_snapshot_id(CLOCK_BOOTTIME, &snap);
> +	boot = ktime_to_ns(snap.systime);
>  
>  	delta_boot = boot - hyp_clock->boot;
>  	delta_cycles = snap.cycles - hyp_clock->cycles;
> @@ -118,9 +118,9 @@ static void hyp_trace_clock_enable(struct hyp_trace_clock *hyp_clock, bool enabl
>  		hyp_clock->running = false;
>  	}
>  
> -	ktime_get_snapshot(&snap);
> +	ktime_get_snapshot_id(&snap, CLOCK_BOOTTIME);

It looks like this instance of ktime_get_snapshot_id() did not get its
arguments swapped when applied, which breaks the build in -next:

  arch/arm64/kvm/hyp_trace.c:121:24: error: incompatible pointer to integer conversion passing 'struct system_time_snapshot *' to parameter of type 'clockid_t' (aka 'int') [-Wint-conversion]
    121 |         ktime_get_snapshot_id(&snap, CLOCK_BOOTTIME);
        |                               ^~~~~
  include/linux/timekeeping.h:357:45: note: passing argument to parameter 'clock_id' here
    357 | extern void ktime_get_snapshot_id(clockid_t clock_id, struct system_time_snapshot *systime_snapshot);
        |                                             ^
  arch/arm64/kvm/hyp_trace.c:121:31: error: incompatible integer to pointer conversion passing 'int' to parameter of type 'struct system_time_snapshot *' [-Wint-conversion]
    121 |         ktime_get_snapshot_id(&snap, CLOCK_BOOTTIME);
        |                                      ^~~~~~~~~~~~~~
  include/uapi/linux/time.h:56:26: note: expanded from macro 'CLOCK_BOOTTIME'
     56 | #define CLOCK_BOOTTIME                  7
        |                                         ^
  include/linux/timekeeping.h:357:84: note: passing argument to parameter 'systime_snapshot' here
    357 | extern void ktime_get_snapshot_id(clockid_t clock_id, struct system_time_snapshot *systime_snapshot);
        |                                                                                    ^
  2 errors generated.

Do you want a fix up patch or do you want to just squash in the fix?

> -	hyp_clock->boot = ktime_to_ns(snap.boot);
> +	hyp_clock->boot = ktime_to_ns(snap.systime);
>  	hyp_clock->cycles = snap.cycles;
>  	hyp_clock->mult = 0;
>  

-- 
Cheers,
Nathan