linux-dev/tools/testing/selftests/powerpc/mm/Makefile, branch master

selftests/powerpc: Add a test for execute-only memory

2022-08-26T01:02:21Z

This selftest is designed to cover execute-only protections on the Radix MMU but will also work with Hash. The tests are based on those found in pkey_exec_test with modifications to use the generic mprotect() instead of the pkey variants. Signed-off-by: Nicholas Miehlbradt Signed-off-by: Russell Currey Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220817050640.406017-2-ruscur@russell.cc

selftests/powerpc: Add a test of 4PB SLB handling

2022-04-29T03:43:22Z

Add a test for a bug we had in the 4PB address space SLB handling. It was fixed in commit 4c2de74cc869 ("powerpc/64: Interrupts save PPR on stack rather than thread_struct"). Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220317143925.1030447-1-mpe@ellerman.id.au

selftests/powerpc: Test for spurious kernel memory faults on radix

2021-04-08T11:17:42Z

Previously when mapping kernel memory on radix, no ptesync was included which would periodically lead to unhandled spurious faults. Mapping kernel memory is used when code patching with Strict RWX enabled. As suggested by Chris Riedl, turning ftrace on and off does a large amount of code patching so is a convenient way to see this kind of fault. Add a selftest to try and trigger this kind of a spurious fault. It tests for 30 seconds which is usually long enough for the issue to show up. Signed-off-by: Jordan Niethe [mpe: Rename it to better reflect what it does, rather than the symptom] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210208032957.1232102-2-jniethe5@gmail.com

Revert "powerpc/64s: Remove PROT_SAO support"

2020-08-24T04:12:53Z

This reverts commit 5c9fa16e8abd342ce04dc830c1ebb2a03abf6c05. Since PROT_SAO can still be useful for certain classes of software, reintroduce it. Concerns about guest migration for LPARs using SAO will be addressed next. Signed-off-by: Shawn Anastasio Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200821185558.35561-2-shawn@anastas.io

selftests/powerpc: Add test of stack expansion logic

2020-07-29T11:02:11Z

We have custom stack expansion checks that it turns out are extremely badly tested and contain bugs, surprise. So add some tests that exercise the code and capture the current boundary conditions. The signal test currently fails on 64-bit kernels because the 2048 byte allowance for the signal frame is too small, we will fix that in a subsequent patch. Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200724092528.1578671-1-mpe@ellerman.id.au

selftests/powerpc: Add test for pkey siginfo verification

2020-07-29T11:02:10Z

Commit c46241a370a61 ("powerpc/pkeys: Check vma before returning key fault error to the user") fixes a bug which causes the kernel to set the wrong pkey in siginfo when a pkey fault occurs after two competing threads that have allocated different pkeys, one fully permissive and the other restrictive, attempt to protect a common page at the same time. This adds a test to detect the bug. Signed-off-by: Sandipan Das Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/ce40b6ee270bda52e8f4088578ed2faf7d1d509a.1595821792.git.sandipan@linux.ibm.com

powerpc/64s: Remove PROT_SAO support

2020-07-21T14:01:25Z

ISA v3.1 does not support the SAO storage control attribute required to implement PROT_SAO. PROT_SAO was used by specialised system software (Lx86) that has been discontinued for about 7 years, and is not thought to be used elsewhere, so removal should not cause problems. We rather remove it than keep support for older processors, because live migrating guest partitions to newer processors may not be possible if SAO is in use (or worse allowed with silent races). - PROT_SAO stays in the uapi header so code using it would still build. - arch_validate_prot() is removed, the generic version rejects PROT_SAO so applications would get a failure at mmap() time. Signed-off-by: Nicholas Piggin [mpe: Drop KVM change for the time being] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200703011958.1166620-3-npiggin@gmail.com

selftests/powerpc: Add test for execute-disabled pkeys

2020-06-30T04:37:54Z

Apart from read and write access, memory protection keys can also be used for restricting execute permission of pages on powerpc. This adds a test to verify if the feature works as expected. Signed-off-by: Sandipan Das Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200604125610.649668-4-sandipan@linux.ibm.com

selftests/powerpc: Move Hash MMU check to utilities

2020-06-30T04:37:51Z

This moves a function to test if the MMU is in Hash mode under the generic test utilities. Signed-off-by: Sandipan Das Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200604125610.649668-3-sandipan@linux.ibm.com

selftests/powerpc: Add a test of bad (out-of-range) accesses

2020-01-06T05:25:27Z

Userspace isn't allowed to access certain address ranges, make sure we actually test that to at least some degree. This would have caught the recent bug where the SLB fault handler was incorrectly called on an out-of-range access when using the Radix MMU. It also would have caught the bug we had in get_region_id() where we were inserting SLB entries for bad addresses. Signed-off-by: Michael Ellerman Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190520102051.12103-1-mpe@ellerman.id.au