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

Atomic instructions such as 'ldset' in the guest have been observed to
cause an EL1 data abort with FSC 0x35 (IMPLEMENTATION D

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

Atomic instructions such as 'ldset' in the guest have been observed to
cause an EL1 data abort with FSC 0x35 (IMPLEMENTATION DEFINED fault
(Unsupported Exclusive or Atomic access)) on Neoverse-N3.

Per DDI0487L.a B2.2.6, atomic instructions are only architecturally
guaranteed for Inner/Outer Shareable Normal Write-Back memory. For
anything else the behavior is IMPLEMENTATION DEFINED and can lose
atomicity, or, in this case, generate an abort.

It would appear that selftests sets up the stage-1 mappings as Non
Shareable, leading to the observed abort. Explicitly set the
Shareability field to Inner Shareable for non-LPA2 page tables. Note
that for the LPA2 page table format, translations for cacheable memory
inherit the shareability attribute of the PTW, i.e. TCR_ELx.SH{0,1}.

Suggested-by: Oliver Upton <[email protected]>
Signed-off-by: Raghavendra Rao Ananta <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[oliver: Rephrase changelog]
Signed-off-by: Oliver Upton <[email protected]>

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KVM: arm64: selftests: Introduce and use hardware-definition macros

The kvm selftest library for arm64 currently configures the hardware
fields, such as shift and mask in the page-table entries and

KVM: arm64: selftests: Introduce and use hardware-definition macros

The kvm selftest library for arm64 currently configures the hardware
fields, such as shift and mask in the page-table entries and registers,
directly with numbers. While it add comments at places, it's better to
rewrite them with appropriate macros to improve the readability and
reduce the risk of errors. Hence, introduce macros to define the
hardware fields and use them in the arm64 processor library.

Most of the definitions are primary copied from the Linux's header,
arch/arm64/include/asm/pgtable-hwdef.h.

No functional change intended.

Suggested-by: Oliver Upton <[email protected]>
Signed-off-by: Raghavendra Rao Ananta <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Oliver Upton <[email protected]>

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KVM: selftests: Use canonical $(ARCH) paths for KVM selftests directories

Use the kernel's canonical $(ARCH) paths instead of the raw target triple
for KVM selftests directories. KVM selftests are

KVM: selftests: Use canonical $(ARCH) paths for KVM selftests directories

Use the kernel's canonical $(ARCH) paths instead of the raw target triple
for KVM selftests directories. KVM selftests are quite nearly the only
place in the entire kernel that using the target triple for directories,
tools/testing/selftests/drivers/s390x being the lone holdout.

Using the kernel's preferred nomenclature eliminates the minor, but
annoying, friction of having to translate to KVM's selftests directories,
e.g. for pattern matching, opening files, running selftests, etc.

Opportunsitically delete file comments that reference the full path of the
file, as they are obviously prone to becoming stale, and serve no known
purpose.

Reviewed-by: Muhammad Usama Anjum <[email protected]>
Acked-by: Claudio Imbrenda <[email protected]>
Acked-by: Andrew Jones <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sean Christopherson <[email protected]>

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