From 93de2a6a4b91b72607136dd656edf03fb399d27f Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 23 Sep 2026 09:37:21 -0700 Subject: KVM: SEV: Do cache maintenance on the source VM during intra-host migration Manually perform cache maintenance on the source VM during intra-host migration to ensure no stale data is left in CPU caches after the VM is destroyed. Because the source VM is "converted" to a non-SEV VM, KVM's memory reclaim flows won't trigger cache maintenance, e.g. when all guest memory is reclaimed in response to detaching from the mmu_notifier. Note, relying on the destination VM to do cache maintenance isn't an option as KVM doesn't require identical guest memory configurations, i.e. the source VM may have access to memory that the destination VM does not. Enforcing equivalent memory configurations is infeasible, as it would require a *deep* comparison of memslots, e.g. to verify that not only are the memslot identical, but what the memslots point at is also identical. Fixes: b56639318bb2 ("KVM: SEV: Add support for SEV intra host migration") Cc: stable@vger.kernel.org Reported-by: Stefan Teodorescu Signed-off-by: Sean Christopherson Message-ID: <20260923163721.1584779-3-seanjc@google.com> Signed-off-by: Paolo Bonzini --- Documentation/ABI/testing/sysfs-class-wakeup | 76 ++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-class-wakeup (limited to 'Documentation/ABI/testing/sysfs-class-wakeup') diff --git a/Documentation/ABI/testing/sysfs-class-wakeup b/Documentation/ABI/testing/sysfs-class-wakeup new file mode 100644 index 000000000..754aab8b6 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-wakeup @@ -0,0 +1,76 @@ +What: /sys/class/wakeup/ +Date: June 2019 +Contact: Tri Vo +Description: + The /sys/class/wakeup/ directory contains pointers to all + wakeup sources in the kernel at that moment in time. + +What: /sys/class/wakeup/.../name +Date: June 2019 +Contact: Tri Vo +Description: + This file contains the name of the wakeup source. + +What: /sys/class/wakeup/.../active_count +Date: June 2019 +Contact: Tri Vo +Description: + This file contains the number of times the wakeup source was + activated. + +What: /sys/class/wakeup/.../event_count +Date: June 2019 +Contact: Tri Vo +Description: + This file contains the number of signaled wakeup events + associated with the wakeup source. + +What: /sys/class/wakeup/.../wakeup_count +Date: June 2019 +Contact: Tri Vo +Description: + This file contains the number of times the wakeup source might + abort suspend. + +What: /sys/class/wakeup/.../expire_count +Date: June 2019 +Contact: Tri Vo +Description: + This file contains the number of times the wakeup source's + timeout has expired. + +What: /sys/class/wakeup/.../active_time_ms +Date: June 2019 +Contact: Tri Vo +Description: + This file contains the amount of time the wakeup source has + been continuously active, in milliseconds. If the wakeup + source is not active, this file contains '0'. + +What: /sys/class/wakeup/.../total_time_ms +Date: June 2019 +Contact: Tri Vo +Description: + This file contains the total amount of time this wakeup source + has been active, in milliseconds. + +What: /sys/class/wakeup/.../max_time_ms +Date: June 2019 +Contact: Tri Vo +Description: + This file contains the maximum amount of time this wakeup + source has been continuously active, in milliseconds. + +What: /sys/class/wakeup/.../last_change_ms +Date: June 2019 +Contact: Tri Vo +Description: + This file contains the monotonic clock time when the wakeup + source was touched last time, in milliseconds. + +What: /sys/class/wakeup/.../prevent_suspend_time_ms +Date: June 2019 +Contact: Tri Vo +Description: + The file contains the total amount of time this wakeup source + has been preventing autosleep, in milliseconds. -- cgit v1.3.1