From: Michael Ellerman Date: Tue, 7 Feb 2017 10:01:01 +0000 (+1100) Subject: powerpc/powernv: Fix opal_exit tracepoint opcode X-Git-Tag: v4.1.41~54 X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ab1b642339b38c8ddaceb65b03ec6bb589c82b7e;p=linux powerpc/powernv: Fix opal_exit tracepoint opcode [ Upstream commit a7e0fb6c2029a780444d09560f739e020d54fe4d ] Currently the opal_exit tracepoint usually shows the opcode as 0: -0 [047] d.h. 635.654292: opal_entry: opcode=63 -0 [047] d.h. 635.654296: opal_exit: opcode=0 retval=0 kopald-1209 [019] d... 636.420943: opal_entry: opcode=10 kopald-1209 [019] d... 636.420959: opal_exit: opcode=0 retval=0 This is because we incorrectly load the opcode into r0 before calling __trace_opal_exit(), whereas it expects the opcode in r3 (first function parameter). In fact we are leaving the retval in r3, so opcode and retval will always show the same value. Instead load the opcode into r3, resulting in: -0 [040] d.h. 636.618625: opal_entry: opcode=63 -0 [040] d.h. 636.618627: opal_exit: opcode=63 retval=0 Fixes: c49f63530bb6 ("powernv: Add OPAL tracepoints") Signed-off-by: Michael Ellerman Signed-off-by: Sasha Levin --- diff --git a/arch/powerpc/platforms/powernv/opal-wrappers.S b/arch/powerpc/platforms/powernv/opal-wrappers.S index a7ade94cdf87..b870f4ca2f80 100644 --- a/arch/powerpc/platforms/powernv/opal-wrappers.S +++ b/arch/powerpc/platforms/powernv/opal-wrappers.S @@ -148,7 +148,7 @@ opal_tracepoint_entry: opal_tracepoint_return: std r3,STK_REG(R31)(r1) mr r4,r3 - ld r0,STK_REG(R23)(r1) + ld r3,STK_REG(R23)(r1) bl __trace_opal_exit ld r3,STK_REG(R31)(r1) addi r1,r1,STACKFRAMESIZE