kernel.git/arch/x86/include/asm/fpu, branch linux-4.12.y

KVM, pkeys: do not use PKRU value in vcpu->arch.guest_fpu.state

2017-08-30T08:26:30Z

commit 38cfd5e3df9c4f88e76b547eee2087ee5c042ae2 upstream. The host pkru is restored right after vcpu exit (commit 1be0e61), so KVM_GET_XSAVE will return the host PKRU value instead. Fix this by using the guest PKRU explicitly in fill_xsave and load_xsave. This part is based on a patch by Junkang Fu. The host PKRU data may also not match the value in vcpu->arch.guest_fpu.state, because it could have been changed by userspace since the last time it was saved, so skip loading it in kvm_load_guest_fpu. Reported-by: Junkang Fu Cc: Yang Zhang Fixes: 1be0e61c1f255faaeab04a390e00c8b9b9042870 Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman

x86/fpu/xstate: Move XSAVES state init to a function

2017-01-25T07:25:12Z

Make XSTATE init similar to existing code; move it to a separate function. There is no functionality change. Signed-off-by: Yu-cheng Yu Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Ravi V. Shankar Cc: Rik van Riel Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1485282346-15437-1-git-send-email-yu-cheng.yu@intel.com [ Minor cleanliness edits. ] Signed-off-by: Ingo Molnar

x86/fpu: Remove irq_ts_save() and irq_ts_restore()

2016-11-01T06:47:54Z

Now that lazy FPU is gone, we don't use CR0.TS (except possibly in KVM guest mode). Remove irq_ts_save(), irq_ts_restore(), and all of their callers. Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Paolo Bonzini Cc: Peter Zijlstra Cc: Quentin Casasnovas Cc: Rik van Riel Cc: Rusty Russell Cc: Thomas Gleixner Cc: kvm list Link: http://lkml.kernel.org/r/70b9b9e7ba70659bedcb08aba63d0f9214f338f2.1477951965.git.luto@kernel.org Signed-off-by: Ingo Molnar

x86/fpu: Finish excising 'eagerfpu'

2016-10-18T07:56:03Z

Now that eagerfpu= is gone, remove it from the docs and some comments. Also sync the changes to tools/. Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Quentin Casasnovas Cc: Rik van Riel Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/cf430dd4481d41280e93ac6cf0def1007a67fc8e.1476740397.git.luto@kernel.org Signed-off-by: Ingo Molnar

x86/fpu: Split old_fpu & new_fpu handling into separate functions

2016-10-16T09:38:41Z

By moving all of the new_fpu state handling into switch_fpu_finish(), the code can be simplified some more. This gets rid of the prefetch, but given the size of the FPU register state on modern CPUs, and the amount of work done by __switch_to() inbetween both functions, the value of a single cache line prefetch seems somewhat dubious anyway. Signed-off-by: Rik van Riel Acked-by: Dave Hansen Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Quentin Casasnovas Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1476447331-21566-3-git-send-email-riel@redhat.com Signed-off-by: Ingo Molnar

x86/fpu: Remove 'cpu' argument from __cpu_invalidate_fpregs_state()

2016-10-16T09:38:31Z

The __{fpu,cpu}_invalidate_fpregs_state() functions can only be used to invalidate a resource they control. Document that, and change the API a little bit to reflect that. Go back to open coding the fpu_fpregs_owner_ctx write in the CPU hotplug code, which should be the exception, and move __kernel_fpu_begin() to this API. This patch has no functional changes to the current code. Signed-off-by: Rik van Riel Acked-by: Dave Hansen Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Quentin Casasnovas Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1476447331-21566-2-git-send-email-riel@redhat.com Signed-off-by: Ingo Molnar

x86/fpu: Split old & new FPU code paths

2016-10-07T09:14:43Z

Now that CR0.TS is no longer being manipulated, we can simplify switch_fpu_prepare() by no longer nesting the handling of new_fpu inside the two branches for the old_fpu. Signed-off-by: Rik van Riel Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Quentin Casasnovas Cc: Thomas Gleixner Cc: pbonzini@redhat.com Link: http://lkml.kernel.org/r/1475627678-20788-10-git-send-email-riel@redhat.com Signed-off-by: Ingo Molnar

x86/fpu: Remove __fpregs_(de)activate()

2016-10-07T09:14:42Z

Now that fpregs_activate() and fpregs_deactivate() do nothing except call the double underscored versions of themselves, we can get rid of the double underscore version. Signed-off-by: Rik van Riel Reviewed-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Quentin Casasnovas Cc: Thomas Gleixner Cc: pbonzini@redhat.com Link: http://lkml.kernel.org/r/1475627678-20788-9-git-send-email-riel@redhat.com Signed-off-by: Ingo Molnar

x86/fpu: Rename lazy restore functions to "register state valid"

2016-10-07T09:14:41Z

Name the functions after the state they track, rather than the function they currently enable. This should make it more obvious when we use the fpu_register_state_valid() function for something else in the future. Signed-off-by: Rik van Riel Reviewed-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Quentin Casasnovas Cc: Thomas Gleixner Cc: pbonzini@redhat.com Link: http://lkml.kernel.org/r/1475627678-20788-8-git-send-email-riel@redhat.com Signed-off-by: Ingo Molnar

x86/fpu: Remove struct fpu::counter

2016-10-07T09:14:40Z

With the lazy FPU code gone, we no longer use the counter field in struct fpu for anything. Get rid it. Signed-off-by: Rik van Riel Reviewed-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Quentin Casasnovas Cc: Thomas Gleixner Cc: pbonzini@redhat.com Link: http://lkml.kernel.org/r/1475627678-20788-6-git-send-email-riel@redhat.com Signed-off-by: Ingo Molnar