From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 659 invoked by alias); 13 Sep 2004 17:36:46 -0000 Mailing-List: contact libc-hacker-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-hacker-owner@sources.redhat.com Received: (qmail 643 invoked from network); 13 Sep 2004 17:36:46 -0000 Received: from unknown (HELO palrel13.hp.com) (156.153.255.238) by sourceware.org with SMTP; 13 Sep 2004 17:36:46 -0000 Received: from hplms2.hpl.hp.com (hplms2.hpl.hp.com [15.0.152.33]) by palrel13.hp.com (Postfix) with ESMTP id CFE211C0DF5B; Mon, 13 Sep 2004 10:36:45 -0700 (PDT) Received: from napali.hpl.hp.com (napali.hpl.hp.com [15.4.89.123]) by hplms2.hpl.hp.com (8.13.1/8.13.1/HPL-PA Hub) with ESMTP id i8DHahWv011151; Mon, 13 Sep 2004 10:36:44 -0700 (PDT) Received: from napali.hpl.hp.com (napali [127.0.0.1]) by napali.hpl.hp.com (8.12.11/8.12.11/Debian-3) with ESMTP id i8DHahPl026531; Mon, 13 Sep 2004 10:36:43 -0700 Received: (from davidm@localhost) by napali.hpl.hp.com (8.12.11/8.12.11/Debian-3) id i8DHah3j026528; Mon, 13 Sep 2004 10:36:43 -0700 From: David Mosberger MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <16709.55979.414777.757138@napali.hpl.hp.com> Date: Mon, 13 Sep 2004 17:36:00 -0000 To: Ulrich Drepper Cc: libc-hacker@sources.redhat.com, davidm@hpl.hp.com Subject: Re: fix ia64 longjmp() to work from alternate signal-stack In-Reply-To: <16701.61869.569801.438219@napali.hpl.hp.com> References: <16684.49335.802840.212013@napali.hpl.hp.com> <412DAC31.1050404@redhat.com> <16692.38122.52348.850833@napali.hpl.hp.com> <413499B2.2030900@redhat.com> <16692.41948.53308.392397@napali.hpl.hp.com> <20040831135945.GJ30497@sunsite.ms.mff.cuni.cz> <16693.36280.331341.924084@napali.hpl.hp.com> <4137A371.9020601@redhat.com> <16701.61869.569801.438219@napali.hpl.hp.com> Reply-To: davidm@hpl.hp.com X-URL: http://www.hpl.hp.com/personal/David_Mosberger/ X-SW-Source: 2004-09/txt/msg00055.txt.bz2 Here is an updated (and working) patch. If it looks OK, please apply. --david ---- ./ChangeLog 2004-09-13 David Mosberger * signal/Versions: Export __sigaltstack with GLIBC_PRIVATE. ./nptl/ChangeLog 2004-09-01 David Mosberger * sysdeps/unix/sysv/linux/ia64/jmpbuf-unwind.h (__libc_unwind_longjmp): Delete macro and declare as function. * sysdeps/unix/sysv/linux/ia64/Makefile (sysdep_routines): Mention __ia64_longjmp, sigstack_longjmp, and __sigstack_longjmp for nptl directory. * sysdeps/unix/sysv/linux/ia64/__ia64_longjmp.S: New file. * sysdeps/unix/sysv/linux/ia64/__sigstack_longjmp.c: Likewise. * sysdeps/unix/sysv/linux/ia64/unwind_longjmp.c: Likewise. Index: nptl/sysdeps/unix/sysv/linux/ia64/Makefile --- /dev/null +++ nptl/sysdeps/unix/sysv/linux/ia64/Makefile @@ -0,0 +1,3 @@ +ifeq ($(subdir),nptl) +libpthread-sysdep_routines += __ia64_longjmp unwind_longjmp __sigstack_longjmp +endif Index: nptl/sysdeps/unix/sysv/linux/ia64/__ia64_longjmp.S --- /dev/null +++ nptl/sysdeps/unix/sysv/linux/ia64/__ia64_longjmp.S @@ -0,0 +1,156 @@ +/* Copyright (C) 1999, 2000, 2001, 2004 Free Software Foundation, Inc. + Contributed by David Mosberger-Tang . + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include +#include + +LEAF(__ia64_flush_rbs) + flushrs + mov r9 = ar.rsc // 12 cyc latency + ;; + mov r8 = ar.bsp // 12 cyc latency + ;; + and r16 = ~0x3, r9 // clear ar.rsc.mode + ;; + mov ar.rsc = r16 // put RSE into enforced-lazy mode + ;; + mov r10 = ar.rnat // 5 cyc latency + ret +END(__ia64_flush_rbs) + + +# define pPos p6 /* is rotate count positive? */ +# define pNeg p7 /* is rotate count negative? */ + +/* __ia64_longjmp(__jmp_buf buf, int val, long rnat, long rsc) */ + + +LEAF(__ia64_longjmp) + alloc r8=ar.pfs,4,0,0,0 + add r2=0x98,in0 // r2 <- &jmpbuf.orig_jmp_buf_addr + add r3=0x88,in0 // r3 <- &jmpbuf.ar_bsp + ;; + ld8 r8=[r2] // r8 <- orig_jmp_buf_addr + ld8 r23=[r3],8 // r23 <- jmpbuf.ar_bsp + mov r2=in0 + ;; + // + // Note: we need to redo the "flushrs" here even though it's + // already been done by __ia64_flush_rbs. It is needed to + // ensure that ar.bspstore == ar.bsp. + // + flushrs // flush dirty regs to backing store + ld8 r25=[r3] // r25 <- jmpbuf.ar_unat + sub r8=r8,in0 // r8 <- &orig_jmpbuf - &jmpbuf + ;; + add r3=8,in0 // r3 <- &jmpbuf.r1 + extr.u r8=r8,3,6 // r8 <- (&orig_jmpbuf - &jmpbuf)/8 & 0x3f + ;; + cmp.lt pNeg,pPos=r8,r0 + ;; +(pPos) mov r16=r8 +(pNeg) add r16=64,r8 +(pPos) sub r17=64,r8 +(pNeg) sub r17=r0,r8 + ;; + shr.u r8=r25,r16 + shl r9=r25,r17 + ;; + or r25=r8,r9 + ;; + mov ar.unat=r25 // setup ar.unat (NaT bits for r1, r4-r7, and r12) + ;; + ld8.fill.nta sp=[r2],16 // r12 (sp) + ld8.fill.nta gp=[r3],16 // r1 (gp) + dep r11=-1,r23,3,6 // r11 <- ia64_rse_rnat_addr(jmpbuf.ar_bsp) + ;; + ld8.nta r16=[r2],16 // caller's unat + ld8.nta r17=[r3],16 // fpsr + ;; + ld8.fill.nta r4=[r2],16 // r4 + ld8.fill.nta r5=[r3],16 // r5 (gp) + ;; + ld8.fill.nta r6=[r2],16 // r6 + ld8.fill.nta r7=[r3],16 // r7 + ;; + mov ar.unat=r16 // restore caller's unat + mov ar.fpsr=r17 // restore fpsr + ;; + ld8.nta r16=[r2],16 // b0 + ld8.nta r17=[r3],16 // b1 + ;; + mov ar.bspstore=r23 // restore ar.bspstore + ld8.nta r18=[r2],16 // b2 + ;; + mov ar.rnat=in2 // restore ar.rnat + ld8.nta r19=[r3],16 // b3 + ;; + ld8.nta r20=[r2],16 // b4 + ld8.nta r21=[r3],16 // b5 + ;; + ld8.nta r11=[r2],16 // ar.pfs + ld8.nta r22=[r3],56 // ar.lc + ;; + ld8.nta r24=[r2],32 // pr + mov ar.rsc=in3 // restore ar.rsc + mov b0=r16 + ;; + ldf.fill.nta f2=[r2],32 + ldf.fill.nta f3=[r3],32 + mov b1=r17 + ;; + ldf.fill.nta f4=[r2],32 + ldf.fill.nta f5=[r3],32 + mov b2=r18 + ;; + ldf.fill.nta f16=[r2],32 + ldf.fill.nta f17=[r3],32 + mov b3=r19 + ;; + ldf.fill.nta f18=[r2],32 + ldf.fill.nta f19=[r3],32 + mov b4=r20 + ;; + ldf.fill.nta f20=[r2],32 + ldf.fill.nta f21=[r3],32 + mov b5=r21 + ;; + ldf.fill.nta f22=[r2],32 + ldf.fill.nta f23=[r3],32 + mov ar.lc=r22 + ;; + ldf.fill.nta f24=[r2],32 + ldf.fill.nta f25=[r3],32 + cmp.eq p8,p9=0,in1 + ;; + ldf.fill.nta f26=[r2],32 + ldf.fill.nta f27=[r3],32 + mov ar.pfs=r11 + ;; + ldf.fill.nta f28=[r2],32 + ldf.fill.nta f29=[r3],32 +(p8) mov r8=1 + ;; + ldf.fill.nta f30=[r2] + ldf.fill.nta f31=[r3] +(p9) mov r8=in1 + + invala // virt. -> phys. regnum mapping may change + mov pr=r24,-1 + ret +END(__ia64_longjmp) Index: nptl/sysdeps/unix/sysv/linux/ia64/__sigstack_longjmp.c --- /dev/null +++ nptl/sysdeps/unix/sysv/linux/ia64/__sigstack_longjmp.c @@ -0,0 +1,166 @@ +/* Copyright (C) 2004 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by David Mosberger-Tang . + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +/* The public __longjmp() implementation is limited to jumping within + the same stack. That is, in general it is not possible to use this + __longjmp() implementation to cross from one stack to another. + In constrast, the __sigstack_longjmp() implemented here allows + crossing from the alternate signal stack to the normal stack + as a special case. */ + +#include +#include +#include +#include +#include + +#include + +#define JB_SP 0 +#define JB_BSP 17 + +struct rbs_flush_values + { + unsigned long bsp; + unsigned long rsc; + unsigned long rnat; + }; + +extern struct rbs_flush_values __ia64_flush_rbs (void); +extern void __ia64_longjmp (__jmp_buf buf, int val, long rnat, long rsc) + __attribute__ ((__noreturn__)); + +static void +copy_rbs (unsigned long *dst, unsigned long *dst_end, unsigned long dst_rnat, + unsigned long *src, unsigned long *src_end, + unsigned long current_rnat) +{ + unsigned long dst_slot, src_rnat = 0, src_slot, *src_rnat_addr, nat_bit; + int first_time = 1; + + while (dst < dst_end) + { + dst_slot = ia64_rse_slot_num (dst); + if (dst_slot == 63) + { + *dst++ = dst_rnat; + dst_rnat = 0; + } + else + { + /* read source value, including NaT bit: */ + src_slot = ia64_rse_slot_num (src); + if (src_slot == 63) + { + /* skip src RNaT slot */ + ++src; + src_slot = 0; + } + if (first_time || src_slot == 0) + { + first_time = 0; + src_rnat_addr = ia64_rse_rnat_addr (src); + if (src_rnat_addr < src_end) + src_rnat = *src_rnat_addr; + else + src_rnat = current_rnat; + } + nat_bit = (src_rnat >> src_slot) & 1; + + assert (src < src_end); + + *dst++ = *src++; + if (nat_bit) + dst_rnat |= (1UL << dst_slot); + else + dst_rnat &= ~(1UL << dst_slot); + } + } + dst_slot = ia64_rse_slot_num (dst); + if (dst_slot > 0) + *ia64_rse_rnat_addr (dst) = dst_rnat; +} + +void +__sigstack_longjmp (__jmp_buf buf, int val) +{ + unsigned long *rbs_base, *bsp, *bspstore, *jb_bsp, jb_sp, ss_sp; + unsigned long ndirty, rnat, load_rnat, *jb_rnat_addr; + struct sigcontext *sc; + stack_t stk; + struct rbs_flush_values c; + + /* put RSE into enforced-lazy mode and return current bsp/rsc/rnat: */ + c = __ia64_flush_rbs (); + + jb_sp = ((unsigned long *) buf)[JB_SP]; + jb_bsp = ((unsigned long **) buf)[JB_BSP]; + + __sigaltstack (NULL, &stk); + + ss_sp = (unsigned long) stk.ss_sp; + jb_rnat_addr = ia64_rse_rnat_addr (jb_bsp); + + if ((stk.ss_flags & SS_ONSTACK) == 0 || jb_sp - ss_sp < stk.ss_size) + /* Normal non-stack-crossing longjmp; if the RNaT slot for the bsp + saved in the jump-buffer is the same as the one for the current + BSP, use the current AR.RNAT value, otherwise, load it from the + jump-buffer's RNaT-slot. */ + load_rnat = (ia64_rse_rnat_addr ((unsigned long *) c.bsp) != jb_rnat_addr); + else + { + /* If we are on the alternate signal-stack and the jump-buffer + lies outside the signal-stack, we may need to copy back the + dirty partition which was torn off and saved on the + signal-stack when the signal was delivered. + + Caveat: we assume that the top of the alternate signal-stack + stores the sigcontext structure of the signal that + caused the switch to the signal-stack. This should + be a fairly safe assumption but the kernel _could_ + do things differently.. */ + sc = ((struct sigcontext *) ((ss_sp + stk.ss_size) & -16) - 1); + + /* As a sanity-check, verify that the register-backing-store base + of the alternate signal-stack is where we expect it. */ + rbs_base = (unsigned long *) + ((ss_sp + sizeof (long) - 1) & -sizeof (long)); + + assert ((unsigned long) rbs_base == sc->sc_rbs_base); + + ndirty = ia64_rse_num_regs (rbs_base, rbs_base + (sc->sc_loadrs >> 19)); + bsp = (unsigned long *) sc->sc_ar_bsp; + bspstore = ia64_rse_skip_regs (bsp, -ndirty); + + if (bspstore < jb_bsp) + /* AR.BSPSTORE at the time of the signal was below the value + of AR.BSP saved in the jump-buffer => copy the missing + portion from the torn off dirty partition which got saved + on the alternate signal-stack. */ + copy_rbs (bspstore, jb_bsp, sc->sc_ar_rnat, + rbs_base, (unsigned long *) c.bsp, c.rnat); + + load_rnat = 1; + } + if (load_rnat) + rnat = *jb_rnat_addr; + else + rnat = c.rnat; + __ia64_longjmp (buf, val, rnat, c.rsc); +} Index: nptl/sysdeps/unix/sysv/linux/ia64/jmpbuf-unwind.h --- nptl/sysdeps/unix/sysv/linux/ia64/jmpbuf-unwind.h +++ nptl/sysdeps/unix/sysv/linux/ia64/jmpbuf-unwind.h @@ -32,5 +32,8 @@ #define _JMPBUF_UNWINDS_ADJ(_jmpbuf, _address, _adj) \ ((uintptr_t)(_address) - (_adj) < (uintptr_t)(((long *)_jmpbuf)[0]) - (_adj)) -/* We use the normal lobngjmp for unwinding. */ -#define __libc_unwind_longjmp(buf, val) __libc_longjmp (buf, val) +/* We use a longjmp() which can cross from the alternate signal-stack + to the normal stack. */ +extern void __libc_unwind_longjmp (sigjmp_buf env, int val) + __attribute__ ((noreturn)); +hidden_proto (__libc_unwind_longjmp) Index: nptl/sysdeps/unix/sysv/linux/ia64/unwind_longjmp.c --- /dev/null +++ nptl/sysdeps/unix/sysv/linux/ia64/unwind_longjmp.c @@ -0,0 +1,44 @@ +/* Copyright (C) 1991,92,94,95,97,98,2000,02,04 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include +#include +#include +#include +#include + +extern void __sigstack_longjmp (__jmp_buf, int) + __attribute__ ((noreturn)); + +/* Like __libc_siglongjmp(), but safe for crossing from alternate + signal stack to normal stack. Needed by NPTL. */ +void +__libc_unwind_longjmp (sigjmp_buf env, int val) +{ + /* Perform any cleanups needed by the frames being unwound. */ + __pthread_cleanup_upto (env->__jmpbuf, CURRENT_STACK_FRAME); + + if (env[0].__mask_was_saved) + /* Restore the saved signal mask. */ + (void) __sigprocmask (SIG_SETMASK, &env[0].__saved_mask, + (sigset_t *) NULL); + + /* Call the machine-dependent function to restore machine state. */ + __sigstack_longjmp (env[0].__jmpbuf, val ?: 1); +} +hidden_def (__libc_unwind_longjmp) Index: signal/Versions --- signal/Versions +++ signal/Versions @@ -49,4 +49,7 @@ # Needed to provide a pointer to the XPG sigpause function. __xpg_sigpause; } + GLIBC_PRIVATE { + __sigaltstack; + } }