BMC/Intel-BMC/linux.git/tools/testing/selftests/powerpc/tm, branch dev-4.6

selftests/powerpc: Fix out of bounds access in TM signal test

2016-03-02T12:34:45+00:00

Gcc helpfully points out that we're accessing past the end of the gprs array: tm-signal-msr-resv.c: In function 'signal_usr1': tm-signal-msr-resv.c:43:37: error: array subscript is above array bounds [-Werror=array-bounds] ucp->uc_mcontext.regs->gpr[PT_MSR] |= (7ULL); We haven't noticed previously because -flto was hiding it somehow. The code is confused, PT_MSR isn't a gpr, instead it's in uc_regs->gregs, so fix it. Signed-off-by: Michael Ellerman

selftests/powerpc: Add test to check if VSRs are corrupted

2015-12-14T09:41:50+00:00

When a transaction is aborted, VSR values should rollback to the checkpointed values before the transaction began. VSRs used elsewhere in the kernel during a transaction, or while the transaction is suspended should not affect the checkpointed values. Prior to the bug fix in commit d31626f70b61 ("powerpc: Don't corrupt transactional state when using FP/VMX in kernel") when VMX was requested by the kernel the .vr_state (which held the checkpointed state of VSRs before the transaction) was overwritten with the current state from outside the transation. Thus if the transaction did not complete, the VSR values would be "rolled back" to potentially incorrect values. Signed-off-by: Rashmica Gupta Signed-off-by: Michael Ellerman

selftests/powerpc: Add TM signal with invalid stack test

2015-12-14T09:41:49+00:00

Test the kernels signal generation code to ensure it can handle an invalid stack pointer when transactional. Signed-off-by: Michael Neuling Tested-by: Anshuman Khandual [mpe: Skip if we don't have TM] Signed-off-by: Michael Ellerman

selftests/powerpc: Add TM signal return test

2015-12-14T09:41:48+00:00

Test the kernel's signal return code to ensure that it doesn't crash when both the transactional and suspend MSR bits are set in the signal context. Signed-off-by: Michael Neuling Tested-by: Anshuman Khandual [mpe: Skip if we don't have TM] Signed-off-by: Michael Ellerman

selftests/powerpc: Skip tm-resched-dscr if we don't have TM

2015-12-14T09:41:48+00:00

Signed-off-by: Michael Ellerman

selftests/powerpc: Move TM helpers into tm.h

2015-12-14T09:41:48+00:00

Move have_htm_nosc() into a new tm.h, and add a new helper, have_htm() which we'll use in the next patch. Signed-off-by: Michael Ellerman

selftests/powerpc: Add have_hwcap2() helper

2015-12-14T09:41:47+00:00

We already do this twice and want to add another so add a helper. Signed-off-by: Michael Ellerman

selftests/powerpc: Move get_auxv_entry() into utils.c

2015-12-14T09:41:47+00:00

This doesn't really belong in harness.c, it's a helper function. So move it into utils.c. Signed-off-by: Michael Ellerman

selftests/powerpc: Allow the tm-syscall test to build with old headers

2015-10-15T09:32:04+00:00

When building against older kernel headers, currently the tm-syscall test fails to build because PPC_FEATURE2_HTM_NOSC is not defined. Tweak the test so that if PPC_FEATURE2_HTM_NOSC is not defined it still builds, but prints a warning at run time and marks the test as skipped. Signed-off-by: Michael Ellerman

powerpc/tm: Abort syscalls in active transactions

2015-06-19T07:10:28+00:00

This patch changes the syscall handler to doom (tabort) active transactions when a syscall is made and return very early without performing the syscall and keeping side effects to a minimum (no CPU accounting or system call tracing is performed). Also included is a new HWCAP2 bit, PPC_FEATURE2_HTM_NOSC, to indicate this behaviour to userspace. Currently, the system call instruction automatically suspends an active transaction which causes side effects to persist when an active transaction fails. This does change the kernel's behaviour, but in a way that was documented as unsupported. It doesn't reduce functionality as syscalls will still be performed after tsuspend; it just requires that the transaction be explicitly suspended. It also provides a consistent interface and makes the behaviour of user code substantially the same across powerpc and platforms that do not support suspended transactions (e.g. x86 and s390). Performance measurements using http://ozlabs.org/~anton/junkcode/null_syscall.c indicate the cost of a normal (non-aborted) system call increases by about 0.25%. Signed-off-by: Sam Bobroff Signed-off-by: Michael Ellerman