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Date:   Tue, 15 Jan 2019 11:43:58 +0100 (CET)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Juergen Gross <jgross@suse.com>
cc:     linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org,
        x86@kernel.org, boris.ostrovsky@oracle.com, sstabellini@kernel.org,
        hpa@zytor.com, mingo@redhat.com, bp@alien8.de, hans@knorrie.org,
        stable@vger.kernel.org
Subject: Re: [PATCH v3] xen: Fix x86 sched_clock() interface for xen
In-Reply-To: <20190114124413.3742-1-jgross@suse.com>
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On Mon, 14 Jan 2019, Juergen Gross wrote:

> Commit f94c8d11699759 ("sched/clock, x86/tsc: Rework the x86 'unstable'
> sched_clock() interface") broke Xen guest time handling across
> migration:
> 
> [  187.249951] Freezing user space processes ... (elapsed 0.001 seconds) done.
> [  187.251137] OOM killer disabled.
> [  187.251137] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
> [  187.252299] suspending xenstore...
> [  187.266987] xen:grant_table: Grant tables using version 1 layout
> [18446743811.706476] OOM killer enabled.
> [18446743811.706478] Restarting tasks ... done.
> [18446743811.720505] Setting capacity to 16777216

I see that it's broken, but the changelog could do with an explanation WHY
it broke.

Other than that this looks about right.

Thanks,

	tglx