kernel/linux.git/tools/testing/selftests/powerpc/security, branch v5.10.89

selftests/powerpc: Fix L1D flushing tests for Power10

2021-05-19T08:12:54+00:00

[ Upstream commit 3a72c94ebfb1f171eba0715998010678a09ec796 ] The rfi_flush and entry_flush selftests work by using the PM_LD_MISS_L1 perf event to count L1D misses. The value of this event has changed over time: - Power7 uses 0x400f0 - Power8 and Power9 use both 0x400f0 and 0x3e054 - Power10 uses only 0x3e054 Rather than relying on raw values, configure perf to count L1D read misses in the most explicit way available. This fixes the selftests to work on systems without 0x400f0 as PM_LD_MISS_L1, and should change no behaviour for systems that the tests already worked on. The only potential downside is that referring to a specific perf event requires PMU support implemented in the kernel for that platform. Signed-off-by: Russell Currey Acked-by: Daniel Axtens Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210223070227.2916871-1-ruscur@russell.cc Signed-off-by: Sasha Levin

selftests/powerpc: refactor entry and rfi_flush tests

2020-11-19T12:47:23+00:00

For simplicity in backporting, the original entry_flush test contained a lot of duplicated code from the rfi_flush test. De-duplicate that code. Signed-off-by: Daniel Axtens Signed-off-by: Michael Ellerman

selftests/powerpc: entry flush test

2020-11-19T12:47:20+00:00

Add a test modelled on the RFI flush test which counts the number of L1D misses doing a simple syscall with the entry flush on and off. For simplicity of backporting, this test duplicates a lot of code from rfi_flush. We clean that up in the next patch. Signed-off-by: Daniel Axtens Signed-off-by: Michael Ellerman

selftests/powerpc: rfi_flush: disable entry flush if present

2020-11-19T12:47:12+00:00

We are about to add an entry flush. The rfi (exit) flush test measures the number of L1D flushes over a syscall with the RFI flush enabled and disabled. But if the entry flush is also enabled, the effect of enabling and disabling the RFI flush is masked. If there is a debugfs entry for the entry flush, disable it during the RFI flush and restore it later. Reported-by: Spoorthy S Signed-off-by: Russell Currey Signed-off-by: Daniel Axtens Signed-off-by: Michael Ellerman

selftests/powerpc: Skip security tests on older CPUs

2020-09-08T12:24:05+00:00

Both these tests use PMU events that only work on newer CPUs, so skip them on older CPUs. Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200819015727.1977134-6-mpe@ellerman.id.au

selftests/powerpc: Move set_dscr() into rfi_flush.c

2020-09-08T12:23:57+00:00

This version of set_dscr() was added for the RFI flush test, and is fairly specific to it. It also clashes with the version of set_dscr() in dscr/dscr.h. So move it into the RFI flush test where it's used. Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200819015727.1977134-3-mpe@ellerman.id.au

selftests/powerpc: Return skip code for spectre_v2

2020-07-29T13:47:52+00:00

When running under older versions of qemu of under newer versions with old machine types, some security features will not be reported to the guest. This will lead the guest OS to consider itself Vulnerable to spectre_v2. So, spectre_v2 test fails in such cases when the host is mitigated and miss predictions cannot be detected as expected by the test. Make it return the skip code instead, for this particular case. We don't want to miss the case when the test fails and the system reports as mitigated or not affected. But it is not a problem to miss failures when the system reports as Vulnerable. Signed-off-by: Thadeu Lima de Souza Cascardo Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200728155039.401445-1-cascardo@canonical.com

.gitignore: add SPDX License Identifier

2020-03-25T10:50:48+00:00

Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada Signed-off-by: Greg Kroah-Hartman

selftests/powerpc: spectre_v2 test must be built 64-bit

2019-11-21T04:41:39+00:00

The spectre_v2 test must be built 64-bit, it includes hand-written asm that is 64-bit only, and segfaults if built 32-bit. Fixes: c790c3d2b0ec ("selftests/powerpc: Add a test of spectre_v2 mitigations") Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20191120023924.13130-1-mpe@ellerman.id.au

selftests/powerpc: Add a test of spectre_v2 mitigations

2019-10-30T04:43:57+00:00

This test uses the PMU to count branch prediction hits/misses for a known loop, and compare the result to the reported spectre v2 mitigation. This gives us a way of sanity checking that the reported mitigation is actually in effect. Sample output for some cases, eg: Power9: sysfs reports: 'Vulnerable' PM_BR_PRED_CCACHE: result 368 running/enabled 5792777124 PM_BR_MPRED_CCACHE: result 319 running/enabled 5792775546 PM_BR_PRED_PCACHE: result 2147483281 running/enabled 5792773128 PM_BR_MPRED_PCACHE: result 213604201 running/enabled 5792771640 Miss percent 9 % OK - Measured branch prediction rates match reported spectre v2 mitigation. sysfs reports: 'Mitigation: Indirect branch serialisation (kernel only)' PM_BR_PRED_CCACHE: result 895 running/enabled 5780320920 PM_BR_MPRED_CCACHE: result 822 running/enabled 5780312414 PM_BR_PRED_PCACHE: result 2147482754 running/enabled 5780308836 PM_BR_MPRED_PCACHE: result 213639731 running/enabled 5780307912 Miss percent 9 % OK - Measured branch prediction rates match reported spectre v2 mitigation. sysfs reports: 'Mitigation: Indirect branch cache disabled' PM_BR_PRED_CCACHE: result 2147483649 running/enabled 20540186160 PM_BR_MPRED_CCACHE: result 2147483649 running/enabled 20540180056 PM_BR_PRED_PCACHE: result 0 running/enabled 20540176090 PM_BR_MPRED_PCACHE: result 0 running/enabled 20540174182 Miss percent 100 % OK - Measured branch prediction rates match reported spectre v2 mitigation. Power8: sysfs reports: 'Vulnerable' PM_BR_PRED_CCACHE: result 2147483649 running/enabled 3505888142 PM_BR_MPRED_CCACHE: result 9 running/enabled 3505882788 Miss percent 0 % OK - Measured branch prediction rates match reported spectre v2 mitigation. sysfs reports: 'Mitigation: Indirect branch cache disabled' PM_BR_PRED_CCACHE: result 2147483649 running/enabled 16931421988 PM_BR_MPRED_CCACHE: result 2147483649 running/enabled 16931416478 Miss percent 100 % OK - Measured branch prediction rates match reported spectre v2 mitigation. success: spectre_v2 Signed-off-by: Michael Ellerman Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190520105520.22274-1-mpe@ellerman.id.au