KVM: SVM: Drop the module param to control SEV-ES DebugSwap

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Rip out the DebugSwap module param, as the sequence of events that led to
its inclusion was one big mistake, the param no longer serves any purpose.

Commit d1f85fbe83 ("KVM: SEV: Enable data breakpoints in SEV-ES") goofed
by not adding a way for the userspace VMM to control the feature.
Functionally, that was fine, but it broke attestation signatures because
SEV_FEATURES are included in the signature.

Commit 5abf6dceb0 ("SEV: disable SEV-ES DebugSwap by default") fixed that
issue, but the underlying flaw of userspace not having a way to control
SEV_FEATURES was still there.

That flaw was addressed by commit 4f5defae70 ("KVM: SEV: introduce
KVM_SEV_INIT2 operation"), and so then 4dd5ecacb9 ("KVM: SEV: allow
SEV-ES DebugSwap again") re-enabled DebugSwap by default.

Now that the dust has settled, the module param doesn't serve any
meaningful purpose.

Cc: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://patch.msgid.link/20260109033101.1005769-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

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This commit is contained in:

Sean Christopherson 2026-01-08 19:31:00 -08:00

parent ca2eccb953

commit 9587dd7a7e

1 changed files with 3 additions and 8 deletions

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arch/x86/kvm/svm/sev.c

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