kernel_optimize_test/tools/testing
Breno Leitao 48dc0ef190 selftests/powerpc: Fix ptrace tm failure
Test ptrace-tm-spd-gpr fails on current kernel (4.19) due to a segmentation
fault that happens on the child process prior to setting cptr[2] = 1. This
causes the parent process to wait forever at 'while (!pptr[2])' and the test to
be killed by the test harness framework by timeout, thus, failing.

The segmentation fault happens because of a inline assembly being
generated as:

	0x10000355c <tm_spd_gpr+492>    lfs    f0, 0(0)

This is reading memory position 0x0 and causing the segmentation fault.

This code is being generated by ASM_LOAD_FPR_SINGLE_PRECISION(flt_4), where
flt_4 is passed to the inline assembly block as:

	[flt_4] "r" (&d)

Since the inline assembly 'r' constraint means any GPR, gpr0 is being
chosen, thus causing this issue when issuing a Load Floating-Point Single
instruction.

This patch simply changes the constraint to 'b', which specify that this
register will be used as base, and r0 is not allowed to be used, avoiding
this issue.

Other than that, removing flt_2 register from the input operands, since it
is not used by the inline assembly code at all.

Cc: stable@vger.kernel.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-26 21:58:58 +11:00
..
fault-injection
ktest
nvdimm tools/testing/nvdimm: improve emulation of smart injection 2018-07-31 17:05:19 -07:00
radix-tree test_ida: check_ida_destroy and check_ida_alloc 2018-08-21 23:54:21 -04:00
scatterlist
selftests selftests/powerpc: Fix ptrace tm failure 2018-10-26 21:58:58 +11:00
vsock