linux/Documentation/virt/kvm/x86
Sean Christopherson 0e3b70aa13 KVM: x86: Document an erratum in KVM_SET_VCPU_EVENTS on Intel CPUs
Document a flaw in KVM's ABI which lets userspace attempt to inject a
"bad" hardware exception event, and thus induce VM-Fail on Intel CPUs.
Fixing the flaw is a fool's errand, as AMD doesn't sanity check the
validity of the error code, Intel CPUs that support CET relax the check
for Protected Mode, userspace can change the mode after queueing an
exception, KVM ignores the error code when emulating Real Mode exceptions,
and so on and so forth.

The VM-Fail itself doesn't harm KVM or the kernel beyond triggering a
ratelimited pr_warn(), so just document the oddity.

Link: https://lore.kernel.org/r/20240802200420.330769-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-11-01 09:22:28 -07:00
..
amd-memory-encryption.rst
cpuid.rst
errata.rst
hypercalls.rst
index.rst
mmu.rst
msr.rst
nested-vmx.rst
running-nested-guests.rst
timekeeping.rst