diff options
author | gnn <gnn@FreeBSD.org> | 2012-06-04 16:15:40 +0000 |
---|---|---|
committer | gnn <gnn@FreeBSD.org> | 2012-06-04 16:15:40 +0000 |
commit | 8b6349798eeb63dcf81b711bad13f1022640bebd (patch) | |
tree | 3069c8e539de6a1cfdc484c87884bd16998d328f /sys/cddl/dev/dtrace | |
parent | af0c1bd2f507f03ce71696fff76105d95285533a (diff) | |
download | FreeBSD-src-8b6349798eeb63dcf81b711bad13f1022640bebd.zip FreeBSD-src-8b6349798eeb63dcf81b711bad13f1022640bebd.tar.gz |
Integrate a fix for a very odd signal delivery problem found
by Bryan Cantril and others in the Solaris/Illumos version of DTrace.
Obtained from: https://www.illumos.org/issues/789
MFC after: 2 weeks
Diffstat (limited to 'sys/cddl/dev/dtrace')
-rw-r--r-- | sys/cddl/dev/dtrace/amd64/dtrace_subr.c | 19 | ||||
-rw-r--r-- | sys/cddl/dev/dtrace/i386/dtrace_subr.c | 19 |
2 files changed, 24 insertions, 14 deletions
diff --git a/sys/cddl/dev/dtrace/amd64/dtrace_subr.c b/sys/cddl/dev/dtrace/amd64/dtrace_subr.c index d80287b..4895231 100644 --- a/sys/cddl/dev/dtrace/amd64/dtrace_subr.c +++ b/sys/cddl/dev/dtrace/amd64/dtrace_subr.c @@ -27,6 +27,10 @@ * Use is subject to license terms. */ +/* + * Copyright (c) 2011, Joyent, Inc. All rights reserved. + */ + #include <sys/param.h> #include <sys/systm.h> #include <sys/types.h> @@ -297,14 +301,15 @@ dtrace_safe_defer_signal(void) } /* - * If we've executed the original instruction, but haven't performed - * the jmp back to t->t_dtrace_npc or the clean up of any registers - * used to emulate %rip-relative instructions in 64-bit mode, do that - * here and take the signal right away. We detect this condition by - * seeing if the program counter is the range [scrpc + isz, astpc). + * If we have executed the original instruction, but we have performed + * neither the jmp back to t->t_dtrace_npc nor the clean up of any + * registers used to emulate %rip-relative instructions in 64-bit mode, + * we'll save ourselves some effort by doing that here and taking the + * signal right away. We detect this condition by seeing if the program + * counter is the range [scrpc + isz, astpc). */ - if (t->t_dtrace_astpc - rp->r_pc < - t->t_dtrace_astpc - t->t_dtrace_scrpc - isz) { + if (rp->r_pc >= t->t_dtrace_scrpc + isz && + rp->r_pc < t->t_dtrace_astpc) { #ifdef __amd64 /* * If there is a scratch register and we're on the diff --git a/sys/cddl/dev/dtrace/i386/dtrace_subr.c b/sys/cddl/dev/dtrace/i386/dtrace_subr.c index e0e9750..e8384bf 100644 --- a/sys/cddl/dev/dtrace/i386/dtrace_subr.c +++ b/sys/cddl/dev/dtrace/i386/dtrace_subr.c @@ -27,6 +27,10 @@ * Use is subject to license terms. */ +/* + * Copyright (c) 2011, Joyent, Inc. All rights reserved. + */ + #include <sys/param.h> #include <sys/systm.h> #include <sys/types.h> @@ -298,14 +302,15 @@ dtrace_safe_defer_signal(void) } /* - * If we've executed the original instruction, but haven't performed - * the jmp back to t->t_dtrace_npc or the clean up of any registers - * used to emulate %rip-relative instructions in 64-bit mode, do that - * here and take the signal right away. We detect this condition by - * seeing if the program counter is the range [scrpc + isz, astpc). + * If we have executed the original instruction, but we have performed + * neither the jmp back to t->t_dtrace_npc nor the clean up of any + * registers used to emulate %rip-relative instructions in 64-bit mode, + * we'll save ourselves some effort by doing that here and taking the + * signal right away. We detect this condition by seeing if the program + * counter is the range [scrpc + isz, astpc). */ - if (t->t_dtrace_astpc - rp->r_pc < - t->t_dtrace_astpc - t->t_dtrace_scrpc - isz) { + if (rp->r_pc >= t->t_dtrace_scrpc + isz && + rp->r_pc < t->t_dtrace_astpc) { #ifdef __amd64 /* * If there is a scratch register and we're on the |