KVM/riscv changes for 6.6

- Zba, Zbs, Zicntr, Zicsr, Zifencei, and Zihpm support for Guest/VM
- Added ONE_REG interface for SATP mode
- Added ONE_REG interface to enable/disable multiple ISA extensions
- Improved error codes returned by ONE_REG interfaces
- Added KVM_GET_REG_LIST ioctl() implementation for KVM RISC-V
- Added get-reg-list selftest for KVM RISC-V

The original author of aarch64/get-reg-list.c (me) was wearing
tunnel vision goggles when implementing str_with_index(). There's
no reason to have such a special case string function. Instead,
take inspiration from glib and implement strdup_printf. The
implementation builds on vasprintf() which requires _GNU_SOURCE,
but we require _GNU_SOURCE in most files already.

Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Haibo Xu <haibo1.xu@intel.com>
Signed-off-by: Anup Patel <anup@brainfault.org>

Add a local version of guest_snprintf() for use in the guest.

Having a local copy allows the guest access to string formatting
options without dependencies on LIBC.  LIBC is problematic because
it heavily relies on both AVX-512 instructions and a TLS, neither of
which are guaranteed to be set up in the guest.

The file guest_sprintf.c was lifted from arch/x86/boot/printf.c and
adapted to work in the guest, including the addition of buffer length.
I.e. s/sprintf/snprintf/

The functions where prefixed with "guest_" to allow guests to
explicitly call them.

A string formatted by this function is expected to succeed or die.  If
something goes wrong during the formatting process a GUEST_ASSERT()
will be thrown.

Signed-off-by: Aaron Lewis <aaronlewis@google.com>
Link: https://lore.kernel.org/all/mtdi6smhur5rqffvpu7qux7mptonw223y2653x2nwzvgm72nlo@zyc4w3kwl3rg
[sean: add a link to the discussion of other options]
Link: https://lore.kernel.org/r/20230729003643.1053367-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Clean up TEST_ASSERT_EQ() so that the (mostly) raw code is captured in the
main assert message, not the helper macro's code.  E.g. make this:

  x86_64/tsc_msrs_test.c:106: __a == __b
  pid=40470 tid=40470 errno=0 - Success
     1	0x000000000040170e: main at tsc_msrs_test.c:106
     2	0x0000000000416f23: __libc_start_call_main at libc-start.o:?
     3	0x000000000041856f: __libc_start_main_impl at ??:?
     4	0x0000000000401ef0: _start at ??:?
  TEST_ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC), val + 1) failed.
	rounded_host_rdmsr(MSR_IA32_TSC) is 0
	val + 1 is 0x1

look like this:

  x86_64/tsc_msrs_test.c:106: rounded_host_rdmsr(MSR_IA32_TSC) == val + 1
  pid=5737 tid=5737 errno=0 - Success
     1	0x0000000000401714: main at tsc_msrs_test.c:106
     2	0x0000000000415c23: __libc_start_call_main at libc-start.o:?
     3	0x000000000041726f: __libc_start_main_impl at ??:?
     4	0x0000000000401e60: _start at ??:?
  0 != 0x1 (rounded_host_rdmsr(MSR_IA32_TSC) != val + 1)

Opportunstically clean up the formatting of the entire macro.

Link: https://lore.kernel.org/r/20230729003643.1053367-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

There is already an ASSERT_EQ macro in the file
tools/testing/selftests/kselftest_harness.h, so currently KVM selftests
can't include test_util.h from the KVM selftests together with that file.
Rename the macro in the KVM selftests to TEST_ASSERT_EQ to avoid the
problem - it is also more similar to the other macros in test_util.h that
way.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Link: https://lore.kernel.org/r/20230712075910.22480-2-thuth@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Print what KVM exit reason a test was expecting and what it actually
got int TEST_ASSERT_KVM_EXIT_REASON().

Signed-off-by: Vipin Sharma <vipinsh@google.com>
Message-Id: <20230204014547.583711-3-vipinsh@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Make TEST_ASSERT_KVM_EXIT_REASON() macro and replace all exit reason
test assert statements with it.

No functional changes intended.

Signed-off-by: Vipin Sharma <vipinsh@google.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Message-Id: <20230204014547.583711-2-vipinsh@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Implement random number generator for guest code to randomize parts
of the test, making it less predictable and a more accurate reflection
of reality.

The random number generator chosen is the Park-Miller Linear
Congruential Generator, a fancy name for a basic and well-understood
random number generator entirely sufficient for this purpose.

Signed-off-by: Colton Lewis <coltonlewis@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20221107182208.479157-2-coltonlewis@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Many KVM selftests take command line arguments which are supposed to be
positive (>0) or non-negative (>=0). Some tests do these validation and
some missed adding the check.

Add atoi_positive() and atoi_non_negative() to validate inputs in
selftests before proceeding to use those values.

Signed-off-by: Vipin Sharma <vipinsh@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221103191719.1559407-7-vipinsh@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

atoi() doesn't detect errors. There is no way to know that a 0 return
is correct conversion or due to an error.

Introduce atoi_paranoid() to detect errors and provide correct
conversion. Replace all atoi() calls with atoi_paranoid().

Signed-off-by: Vipin Sharma <vipinsh@google.com>
Suggested-by: David Matlack <dmatlack@google.com>
Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221103191719.1559407-4-vipinsh@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>