[DTrace-devel] [PATCH] Fix trampoline use of BPF stack for scratch

[eugene.loh at oracle.com]

From: Eugene Loh <eugene.loh at oracle.com>

Signed-off-by: Eugene Loh <eugene.loh at oracle.com>
---
 libdtrace/dt_prov_proc.c                         | 14 +++++++-------
 test/unittest/lquantize/tst.32bit-bug26268136.sh |  1 -
 2 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/libdtrace/dt_prov_proc.c b/libdtrace/dt_prov_proc.c
index 0223c5d18..58e8ad147 100644
--- a/libdtrace/dt_prov_proc.c
+++ b/libdtrace/dt_prov_proc.c
@@ -62,7 +62,7 @@ static const char		modname[] = "vmlinux";
  * The dependent probe support should include a priority specification to drive
  * the order in which dependent probes are added to the underlying probe.  This
  * is needed to enforce specific probe firing semantics (e.g. proc:::start must
- * always precede [roc:::lwp-start).
+ * always precede [proc:::lwp-start).
  */
 
 typedef struct probe_arg {
@@ -350,12 +350,12 @@ static int trampoline(dt_pcb_t *pcb, uint_t exitlbl)
 		 *	else args[0] = 2;			// CLD_KILLED
 		 */
 		emit(dlp,  BPF_MOV_REG(BPF_REG_1, BPF_REG_FP));
-		emit(dlp,  BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, DT_STK_SPILL(0)));
+		emit(dlp,  BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, DT_TRAMP_SP_SLOT(0)));
 		emit(dlp,  BPF_MOV_IMM(BPF_REG_2, sizeof(int)));
 		emit(dlp,  BPF_LOAD(BPF_DW, BPF_REG_3, BPF_REG_7, DMST_ARG(0)));
 		emit(dlp,  BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, ctm.ctm_offset / NBBY));
 		emit(dlp,  BPF_CALL_HELPER(BPF_FUNC_probe_read));
-		emit(dlp,  BPF_LOAD(BPF_W, BPF_REG_1, BPF_REG_FP, DT_STK_SPILL(0)));
+		emit(dlp,  BPF_LOAD(BPF_W, BPF_REG_1, BPF_REG_FP, DT_TRAMP_SP_SLOT(0)));
 		emit(dlp,  BPF_MOV_IMM(BPF_REG_0, 1));
 		emit(dlp,  BPF_MOV_REG(BPF_REG_2, BPF_REG_1));
 		emit(dlp,  BPF_ALU64_IMM(BPF_AND, BPF_REG_2, 0x7f));
@@ -406,17 +406,17 @@ static int trampoline(dt_pcb_t *pcb, uint_t exitlbl)
 		emit(dlp, BPF_MOV_REG(BPF_REG_3, BPF_REG_0));
 		emit(dlp, BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, off));
 		emit(dlp, BPF_MOV_REG(BPF_REG_1, BPF_REG_FP));
-		emit(dlp, BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, DT_STK_SPILL(0)));
+		emit(dlp, BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, DT_TRAMP_SP_SLOT(0)));
 		emit(dlp, BPF_MOV_IMM(BPF_REG_2, sz));
 		emit(dlp, BPF_CALL_HELPER(BPF_FUNC_probe_read));
-		emit(dlp, BPF_LOAD(BPF_DW, BPF_REG_3, BPF_REG_FP, DT_STK_SPILL(0)));
+		emit(dlp, BPF_LOAD(BPF_DW, BPF_REG_3, BPF_REG_FP, DT_TRAMP_SP_SLOT(0)));
 		off = dt_cg_ctf_offsetof("struct signal_struct", "group_exit_code", &sz, 0);
 		emit(dlp, BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, off));
 		emit(dlp, BPF_MOV_REG(BPF_REG_1, BPF_REG_FP));
-		emit(dlp, BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, DT_STK_SPILL(0)));
+		emit(dlp, BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, DT_TRAMP_SP_SLOT(0)));
 		emit(dlp, BPF_MOV_IMM(BPF_REG_2, sz));
 		emit(dlp, BPF_CALL_HELPER(BPF_FUNC_probe_read));
-		emit(dlp, BPF_LOAD(BPF_W, BPF_REG_0, BPF_REG_FP, DT_STK_SPILL(0)));
+		emit(dlp, BPF_LOAD(BPF_W, BPF_REG_0, BPF_REG_FP, DT_TRAMP_SP_SLOT(0)));
 		emit(dlp, BPF_BRANCH_IMM(BPF_JEQ, BPF_REG_0, 0, lbl_keep));
 		emit(dlp, BPF_STORE(BPF_DW, BPF_REG_7, DMST_ARG(0), BPF_REG_0));
 
diff --git a/test/unittest/lquantize/tst.32bit-bug26268136.sh b/test/unittest/lquantize/tst.32bit-bug26268136.sh
index d5f143f58..a360fd17e 100755
--- a/test/unittest/lquantize/tst.32bit-bug26268136.sh
+++ b/test/unittest/lquantize/tst.32bit-bug26268136.sh
@@ -5,7 +5,6 @@
 # Licensed under the Universal Permissive License v 1.0 as shown at
 # http://oss.oracle.com/licenses/upl.
 #
-# @@xfail: dtv2
 
 if [ $# != 1 ]; then
 	echo expected one argument: '<'dtrace-path'>'
-- 
2.43.5