[src/trunk]: src/sys/arch/powerpc Fix SS_ONSTACK, which seems like broken sin...

[rin <rin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/d5620dda6566
branches:  trunk
changeset: 973113:d5620dda6566
user:      rin <rin%NetBSD.org@localhost>
date:      Sun Jun 21 00:00:27 2020 +0000

description:
Fix SS_ONSTACK, which seems like broken since switched to siginfo.

Found by tests/lib/libc/sys/t_sigaltstack, which passes now, while
no other tests are not falling newly.

XXX
Shouldn't we turn _UC_{SET,CLR}STACK into MI?

diffstat:

 sys/arch/powerpc/include/mcontext.h    |   4 +++-
 sys/arch/powerpc/powerpc/sig_machdep.c |  14 ++++++++++++--
 2 files changed, 15 insertions(+), 3 deletions(-)

diffs (67 lines):

diff -r fbbede5ecc9a -r d5620dda6566 sys/arch/powerpc/include/mcontext.h
--- a/sys/arch/powerpc/include/mcontext.h       Sat Jun 20 21:58:17 2020 +0000
+++ b/sys/arch/powerpc/include/mcontext.h       Sun Jun 21 00:00:27 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: mcontext.h,v 1.18 2018/02/15 15:53:56 kamil Exp $      */
+/*     $NetBSD: mcontext.h,v 1.19 2020/06/21 00:00:27 rin Exp $        */
 
 /*-
  * Copyright (c) 2001 The NetBSD Foundation, Inc.
@@ -131,6 +131,8 @@
 #define        _UC_POWERPC_VEC 0x00010000      /* Vector Register File valid */
 #define        _UC_POWERPC_SPE 0x00020000      /* Vector Register File valid */
 #define        _UC_TLSBASE     0x00080000      /* thread context valid in R2 */
+#define        _UC_SETSTACK    0x00100000
+#define        _UC_CLRSTACK    0x00200000
 
 #define _UC_MACHINE_SP(uc)     ((uc)->uc_mcontext.__gregs[_REG_R1])
 #define _UC_MACHINE_FP(uc)     ((uc)->uc_mcontext.__gregs[_REG_R31])
diff -r fbbede5ecc9a -r d5620dda6566 sys/arch/powerpc/powerpc/sig_machdep.c
--- a/sys/arch/powerpc/powerpc/sig_machdep.c    Sat Jun 20 21:58:17 2020 +0000
+++ b/sys/arch/powerpc/powerpc/sig_machdep.c    Sun Jun 21 00:00:27 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: sig_machdep.c,v 1.48 2020/04/11 09:15:23 rin Exp $     */
+/*     $NetBSD: sig_machdep.c,v 1.49 2020/06/21 00:00:27 rin Exp $     */
 
 /*
  * Copyright (C) 1995, 1996 Wolfgang Solfrank.
@@ -32,7 +32,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sig_machdep.c,v 1.48 2020/04/11 09:15:23 rin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sig_machdep.c,v 1.49 2020/06/21 00:00:27 rin Exp $");
 
 #include "opt_ppcarch.h"
 #include "opt_altivec.h"
@@ -91,6 +91,8 @@
        /* Save register context. */
        memset(&uc, 0, sizeof(uc));
        uc.uc_flags = _UC_SIGMASK;
+       uc.uc_flags |= (ss->ss_flags & SS_ONSTACK) ?
+           _UC_SETSTACK : _UC_CLRSTACK;
        uc.uc_sigmask = *mask;
        uc.uc_link = l->l_ctxlink;
        sendsig_reset(l, ksi->ksi_signo);
@@ -199,6 +201,7 @@
 {
        struct trapframe * const tf = l->l_md.md_utf;
        const __greg_t * const gr = mcp->__gregs;
+       struct proc * const p = l->l_proc;
        int error;
 
        /* Restore GPR context, if any. */
@@ -261,6 +264,13 @@
                vec_restore_from_mcontext(l, mcp);
 #endif
 
+       mutex_enter(p->p_lock);
+       if (flags & _UC_SETSTACK)
+               l->l_sigstk.ss_flags |= SS_ONSTACK;
+       if (flags & _UC_CLRSTACK)
+               l->l_sigstk.ss_flags &= ~SS_ONSTACK;
+       mutex_exit(p->p_lock);
+
        return (0);
 }