linux-toradex.git/arch/x86, branch v4.20

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2018-12-21T19:15:36+00:00

Pull kvm fix from Paolo Bonzini:
 "A simple patch for a pretty bad bug: Unbreak AMD nested
  virtualization."

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: nSVM: fix switch to guest mmu

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-12-21T17:22:24+00:00

Pull x86 fixes from Ingo Molnar:
 "The biggest part is a series of reverts for the macro based GCC
  inlining workarounds. It caused regressions in distro build and other
  kernel tooling environments, and the GCC project was very receptive to
  fixing the underlying inliner weaknesses - so as time ran out we
  decided to do a reasonably straightforward revert of the patches. The
  plan is to rely on the 'asm inline' GCC 9 feature, which might be
  backported to GCC 8 and could thus become reasonably widely available
  on modern distros.

  Other than those reverts, there's misc fixes from all around the
  place.

  I wish our final x86 pull request for v4.20 was smaller..."

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "kbuild/Makefile: Prepare for using macros in inline assembly code to work around asm() related GCC inlining bugs"
  Revert "x86/objtool: Use asm macros to work around GCC inlining bugs"
  Revert "x86/refcount: Work around GCC inlining bug"
  Revert "x86/alternatives: Macrofy lock prefixes to work around GCC inlining bugs"
  Revert "x86/bug: Macrofy the BUG table section handling, to work around GCC inlining bugs"
  Revert "x86/paravirt: Work around GCC inlining bugs when compiling paravirt ops"
  Revert "x86/extable: Macrofy inline assembly code to work around GCC inlining bugs"
  Revert "x86/cpufeature: Macrofy inline assembly code to work around GCC inlining bugs"
  Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"
  x86/mtrr: Don't copy uninitialized gentry fields back to userspace
  x86/fsgsbase/64: Fix the base write helper functions
  x86/mm/cpa: Fix cpa_flush_array() TLB invalidation
  x86/vdso: Pass --eh-frame-hdr to the linker
  x86/mm: Fix decoy address handling vs 32-bit builds
  x86/intel_rdt: Ensure a CPU remains online for the region's pseudo-locking sequence
  x86/dump_pagetables: Fix LDT remap address marker
  x86/mm: Fix guard hole handling

KVM: x86: nSVM: fix switch to guest mmu

2018-12-19T21:19:22+00:00

Recent optimizations in MMU code broke nested SVM with NPT in L1
completely: when we do nested_svm_{,un}init_mmu_context() we want
to switch from TDP MMU to shadow MMU, both init_kvm_tdp_mmu() and
kvm_init_shadow_mmu() check if re-configuration is needed by looking
at cache source data. The data, however, doesn't change - it's only
the type of the MMU which changes. We end up not re-initializing
guest MMU as shadow and everything goes off the rails.

The issue could have been fixed by putting MMU type into extended MMU
role but this is not really needed. We can just split root and guest MMUs
the exact same way we did for nVMX, their types never change in the
lifetime of a vCPU.

There is still room for improvement: currently, we reset all MMU roots
when switching from L1 to L2 and back and this is not needed.

Fixes: 7dcd57552008 ("x86/kvm/mmu: check if tdp/shadow MMU reconfiguration is needed")
Signed-off-by: Vitaly Kuznetsov 
Signed-off-by: Paolo Bonzini

Revert "kbuild/Makefile: Prepare for using macros in inline assembly code to work around asm() related GCC inlining bugs"

2018-12-19T11:00:28+00:00

This reverts commit 77b0bf55bc675233d22cd5df97605d516d64525e.

See this commit for details about the revert:

  e769742d3584 ("Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"")

 Conflicts:
	arch/x86/Makefile

Reported-by: Masahiro Yamada 
Reviewed-by: Borislav Petkov 
Reviewed-by: Thomas Gleixner 
Cc: Juergen Gross 
Cc: Richard Biener 
Cc: Kees Cook 
Cc: Segher Boessenkool 
Cc: Ard Biesheuvel 
Cc: Peter Zijlstra 
Cc: Josh Poimboeuf 
Cc: Nadav Amit 
Cc: Linus Torvalds 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

Revert "x86/objtool: Use asm macros to work around GCC inlining bugs"

2018-12-19T11:00:23+00:00

This reverts commit c06c4d8090513f2974dfdbed2ac98634357ac475.

See this commit for details about the revert:

  e769742d3584 ("Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"")

Reported-by: Masahiro Yamada 
Reviewed-by: Borislav Petkov 
Reviewed-by: Thomas Gleixner 
Cc: Juergen Gross 
Cc: Richard Biener 
Cc: Kees Cook 
Cc: Segher Boessenkool 
Cc: Ard Biesheuvel 
Cc: Peter Zijlstra 
Cc: Josh Poimboeuf 
Cc: Nadav Amit 
Cc: Linus Torvalds 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

Revert "x86/refcount: Work around GCC inlining bug"

2018-12-19T11:00:09+00:00

This reverts commit 9e1725b410594911cc5981b6c7b4cea4ec054ca8.

See this commit for details about the revert:

  e769742d3584 ("Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"")

The conflict resolution for interaction with:

  288e4521f0f6: ("x86/asm: 'Simplify' GEN_*_RMWcc() macros")

was provided by Masahiro Yamada.

 Conflicts:
	arch/x86/include/asm/refcount.h

Reported-by: Masahiro Yamada 
Reviewed-by: Borislav Petkov 
Reviewed-by: Thomas Gleixner 
Cc: Juergen Gross 
Cc: Richard Biener 
Cc: Kees Cook 
Cc: Segher Boessenkool 
Cc: Ard Biesheuvel 
Cc: Peter Zijlstra 
Cc: Josh Poimboeuf 
Cc: Nadav Amit 
Cc: Linus Torvalds 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

Revert "x86/alternatives: Macrofy lock prefixes to work around GCC inlining bugs"

2018-12-19T11:00:04+00:00

This reverts commit 77f48ec28e4ccff94d2e5f4260a83ac27a7f3099.

See this commit for details about the revert:

  e769742d3584 ("Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"")

Reported-by: Masahiro Yamada 
Reviewed-by: Borislav Petkov 
Reviewed-by: Thomas Gleixner 
Cc: Juergen Gross 
Cc: Richard Biener 
Cc: Kees Cook 
Cc: Segher Boessenkool 
Cc: Ard Biesheuvel 
Cc: Peter Zijlstra 
Cc: Josh Poimboeuf 
Cc: Nadav Amit 
Cc: Linus Torvalds 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

Revert "x86/bug: Macrofy the BUG table section handling, to work around GCC inlining bugs"

2018-12-19T11:00:00+00:00

This reverts commit f81f8ad56fd1c7b99b2ed1c314527f7d9ac447c6.

See this commit for details about the revert:

  e769742d3584 ("Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"")

Reported-by: Masahiro Yamada 
Reviewed-by: Borislav Petkov 
Reviewed-by: Thomas Gleixner 
Cc: Juergen Gross 
Cc: Richard Biener 
Cc: Kees Cook 
Cc: Segher Boessenkool 
Cc: Ard Biesheuvel 
Cc: Peter Zijlstra 
Cc: Josh Poimboeuf 
Cc: Nadav Amit 
Cc: Linus Torvalds 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

Revert "x86/paravirt: Work around GCC inlining bugs when compiling paravirt ops"

2018-12-19T10:59:55+00:00

This reverts commit 494b5168f2de009eb80f198f668da374295098dd.

See this commit for details about the revert:

  e769742d3584 ("Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"")

Reported-by: Masahiro Yamada 
Reviewed-by: Borislav Petkov 
Reviewed-by: Thomas Gleixner 
Cc: Juergen Gross 
Cc: Richard Biener 
Cc: Kees Cook 
Cc: Segher Boessenkool 
Cc: Ard Biesheuvel 
Cc: Peter Zijlstra 
Cc: Josh Poimboeuf 
Cc: Nadav Amit 
Cc: Linus Torvalds 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

Revert "x86/extable: Macrofy inline assembly code to work around GCC inlining bugs"

2018-12-19T10:59:47+00:00

This reverts commit 0474d5d9d2f7f3b11262f7bf87d0e7314ead9200.

See this commit for details about the revert:

  e769742d3584 ("Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"")

Reported-by: Masahiro Yamada 
Reviewed-by: Borislav Petkov 
Reviewed-by: Thomas Gleixner 
Cc: Juergen Gross 
Cc: Richard Biener 
Cc: Kees Cook 
Cc: Segher Boessenkool 
Cc: Ard Biesheuvel 
Cc: Peter Zijlstra 
Cc: Josh Poimboeuf 
Cc: Nadav Amit 
Cc: Linus Torvalds 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar