[v2] KVM : selftests: arm64: Explicitly set the page attrs to Inner-Shareable

[PATCH v2 0/2] KVM : selftests: arm64: Explicitly set the page attrs to Inner-Shareable

Posted by Raghavendra Rao Ananta 10 months, 1 week ago

The series fixes a conflict in memory attributes in some
implementations,
such as Neoverse-N3, that causes a data abort in guest EL1 with FSC
0x35 (IMPLEMENTATION DEFINED fault (Unsupported Exclusive or Atomic
access)).

Patch-1 is a cleanup patch that replaces numbers (and comments) to
using proper macros for hardware configuration, such as registers and
page-table entries.

Patch-2 fixes the actual bug and sets the page attrs to Inner-Shareable
by default for the VMs created in the selftests. More details are
presented in the commit text.

v1: https://lore.kernel.org/all/20250404220659.1312465-1-rananta@google.com/

v1 -> v2: Addressed Oliver's comments (thank you)
 - Moved the TCR_* macros from tools' sysreg.h to selftests' local processor.h
   in patch-1.
 - Adjsted the citations to describe the issue more appropriately in
   patch-2.

Raghavendra Rao Ananta (2):
  KVM: selftests: arm64: Introduce and use hardware-definition macros
  KVM: selftests: arm64: Explicitly set the page attrs to
    Inner-Shareable

 .../selftests/kvm/arm64/page_fault_test.c     |  2 +-
 .../selftests/kvm/include/arm64/processor.h   | 67 +++++++++++++++++--
 .../selftests/kvm/lib/arm64/processor.c       | 60 ++++++++++-------
 3 files changed, 96 insertions(+), 33 deletions(-)


base-commit: 38fec10eb60d687e30c8c6b5420d86e8149f7557
-- 
2.49.0.504.g3bcea36a83-goog

Re: [PATCH v2 0/2] KVM : selftests: arm64: Explicitly set the page attrs to Inner-Shareable

Posted by Oliver Upton 10 months ago

On Sat, 05 Apr 2025 00:10:40 +0000, Raghavendra Rao Ananta wrote:
> The series fixes a conflict in memory attributes in some
> implementations,
> such as Neoverse-N3, that causes a data abort in guest EL1 with FSC
> 0x35 (IMPLEMENTATION DEFINED fault (Unsupported Exclusive or Atomic
> access)).
> 
> Patch-1 is a cleanup patch that replaces numbers (and comments) to
> using proper macros for hardware configuration, such as registers and
> page-table entries.
> 
> [...]

I cleaned up the changelog on patch 2 per the discussion + added a note
about the interaction with LPA2.

Applied to fixes, thanks!

[1/2] KVM: selftests: arm64: Introduce and use hardware-definition macros
      https://git.kernel.org/kvmarm/kvmarm/c/d8d78398e550
[2/2] KVM: selftests: arm64: Explicitly set the page attrs to Inner-Shareable
      https://git.kernel.org/kvmarm/kvmarm/c/c8631ea59b65

--
Best,
Oliver