Author: markj
Date: Mon Oct 21 04:15:55 2013
New Revision: 256822
URL: http://svnweb.freebsd.org/changeset/base/256822
Log:
When fetching function arguments out of a frame on amd64, explicitly select
the register based on the argument index rather than relying on the fields
in struct reg to be in the right order. This assumption is incorrect on
FreeBSD and generally led to bogus argument values for the sixth argument
of PID and USDT probes; the first five are passed directly to dtrace_probe()
via the fasttrap trap handler and so were correctly handled.
MFC after: 2 weeks
Modified:
head/sys/cddl/contrib/opensolaris/uts/intel/dtrace/fasttrap_isa.c
head/sys/cddl/dev/dtrace/amd64/dtrace_isa.c
Modified: head/sys/cddl/contrib/opensolaris/uts/intel/dtrace/fasttrap_isa.c
==============================================================================
--- head/sys/cddl/contrib/opensolaris/uts/intel/dtrace/fasttrap_isa.c Mon Oct
21 04:00:23 2013 (r256821)
+++ head/sys/cddl/contrib/opensolaris/uts/intel/dtrace/fasttrap_isa.c Mon Oct
21 04:15:55 2013 (r256822)
@@ -272,7 +272,20 @@ fasttrap_anarg(struct reg *rp, int funct
* registers.
*/
if (argno < 6)
- return ((&rp->r_rdi)[argno]);
+ switch (argno) {
+ case 0:
+ return (rp->r_rdi);
+ case 1:
+ return (rp->r_rsi);
+ case 2:
+ return (rp->r_rdx);
+ case 3:
+ return (rp->r_rcx);
+ case 4:
+ return (rp->r_r8);
+ case 5:
+ return (rp->r_r9);
+ }
stack = (uintptr_t *)rp->r_rsp;
DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
Modified: head/sys/cddl/dev/dtrace/amd64/dtrace_isa.c
==============================================================================
--- head/sys/cddl/dev/dtrace/amd64/dtrace_isa.c Mon Oct 21 04:00:23 2013
(r256821)
+++ head/sys/cddl/dev/dtrace/amd64/dtrace_isa.c Mon Oct 21 04:15:55 2013
(r256822)
@@ -367,7 +367,27 @@ dtrace_getarg(int arg, int aframes)
sizeof (uintptr_t));
if (arg <= inreg) {
- stack = (uintptr_t *)&rp->r_rdi;
+ switch (arg) {
+ case 0:
+ stack = (uintptr_t *)&rp->r_rdi;
+ break;
+ case 1:
+ stack = (uintptr_t *)&rp->r_rsi;
+ break;
+ case 2:
+ stack = (uintptr_t *)&rp->r_rdx;
+ break;
+ case 3:
+ stack = (uintptr_t *)&rp->r_rcx;
+ break;
+ case 4:
+ stack = (uintptr_t *)&rp->r_r8;
+ break;
+ case 5:
+ stack = (uintptr_t *)&rp->r_r9;
+ break;
+ }
+ arg = 0;
} else {
stack = (uintptr_t *)(rp->r_rsp);
arg -= inreg;
_______________________________________________
svn-src-head@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
