4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Anton Blanchard <an...@samba.org> commit 87c4b83e0fe234a1f0eed131ab6fa232036860d5 upstream. The mcrf emulation code was using the CR field number directly as the shift value, without taking into account that CR fields are numbered from 0-7 starting at the high bits. That meant it was looking at the CR fields in the reverse order. Fixes: cf87c3f6b647 ("powerpc: Emulate icbi, mcrf and conditional-trap instructions") Signed-off-by: Anton Blanchard <an...@samba.org> Acked-by: Naveen N. Rao <naveen.n....@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <m...@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- arch/powerpc/lib/sstep.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/arch/powerpc/lib/sstep.c +++ b/arch/powerpc/lib/sstep.c @@ -687,8 +687,10 @@ int __kprobes analyse_instr(struct instr case 19: switch ((instr >> 1) & 0x3ff) { case 0: /* mcrf */ - rd = (instr >> 21) & 0x1c; - ra = (instr >> 16) & 0x1c; + rd = 7 - ((instr >> 23) & 0x7); + ra = 7 - ((instr >> 18) & 0x7); + rd *= 4; + ra *= 4; val = (regs->ccr >> ra) & 0xf; regs->ccr = (regs->ccr & ~(0xfUL << rd)) | (val << rd); goto instr_done;