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40e0ee6338
Extend vmx_dirty_log_test to include accesses made by L2 when EPT is
disabled.
This commit adds explicit coverage of a bug caught by syzkaller, where
the TDP MMU would clear D-bits instead of write-protecting SPTEs being
used to map an L2, which only happens when L1 does not enable EPT,
causing writes made by L2 to not be reflected in the dirty log when PML
is enabled:
$ ./vmx_dirty_log_test
Nested EPT: disabled
==== Test Assertion Failure ====
x86_64/vmx_dirty_log_test.c:151: test_bit(0, bmap)
pid=72052 tid=72052 errno=4 - Interrupted system call
(stack trace empty)
Page 0 incorrectly reported clean
Opportunistically replace the volatile casts with {READ,WRITE}_ONCE().
Link: https://lore.kernel.org/kvm/000000000000c6526f06137f18cc@google.com/
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20240315230541.1635322-5-dmatlack@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.