tree 75e04b4e5cc558fa5ca7de6ce69ea31d05c4c0a9
parent a0ff0611c2fbde94f6c9db8351939b08f2cb6797
author Thomas Gleixner <tglx@linutronix.de> 1634260573 +0200
committer Borislav Petkov <bp@suse.de> 1634736447 +0200

x86/fpu: Replace KVMs home brewed FPU copy from user

Copying a user space buffer to the memory buffer is already available in
the FPU core. The copy mechanism in KVM lacks sanity checks and needs to
use cpuid() to lookup the offset of each component, while the FPU core has
this information cached.

Make the FPU core variant accessible for KVM and replace the home brewed
mechanism.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: kvm@vger.kernel.org
Link: https://lkml.kernel.org/r/20211015011539.134065207@linutronix.de