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Date:   Wed, 11 Jan 2023 12:45:39 +0100
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Subject: Re: Wake-up from suspend to RAM broken under `retbleed=stuff`
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To:     Andrew Cooper <Andrew.Cooper3@citrix.com>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "x86@kernel.org" <x86@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Juergen Gross <jgross@suse.com>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        xen-devel <xen-devel@lists.xenproject.org>,
        Roger Pau Monne <roger.pau@citrix.com>,
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        Joan Bruguera <joanbrugueram@gmail.com>
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From:   Jan Beulich <jbeulich@suse.com>
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On 11.01.2023 12:39, Andrew Cooper wrote:
> The bigger issue with stuff accounting is that nothing AFAICT accounts
> for the fact that any hypercall potentially empties the RSB in otherwise
> synchronous program flow.

But that's not just at hypercall boundaries, but effectively anywhere
(i.e. whenever the hypervisor decides to de-schedule the vCPU)?

Jan