From patchwork Mon Dec 11 19:06:54 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella Netto X-Patchwork-Id: 24868 Received: (qmail 42016 invoked by alias); 11 Dec 2017 19:07:30 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 41986 invoked by uid 89); 11 Dec 2017 19:07:29 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-25.9 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_PASS autolearn=ham version=3.3.2 spammy=mmi, Different, renders, incur X-HELO: mail-qt0-f193.google.com X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references; bh=jGWXbBZweZPCLKNmK3QSueBU2WZ+JiAOoWEv0RLZlZc=; b=t20BbR9vkdu/f2293PPZQL6O9S1IMI+so78do+X5UyrNpiworL4loe+hDun4B9UwBQ xqNLCTUtHC4GKEmUnloidCqyIQtYiAzGrn3rCJ+u0MK4RVz1wzBu32ELfVQEST2FP4VY eMg8pyLr0YNq3kLUj1lLtV4EvRkTZwDdSB12gpLrEBjuhoNPmsqlTVCzNF9Bh7EWtiqG VADUJE7xDjG3KSb4h8TWe7YWJ4pcpejN7rmd7J28Ybz5qpxdBcg/4Gc2Td6+I8CSaHqb hTIKkKtrfpb6g3ASwPKtGm4TvnLLonxMwAwp6YhlXJV6C7yx2+HEwC2aZqQ+rQP/ATX/ EmfA== X-Gm-Message-State: AKGB3mJ5xLaHaM13Wzt3NwxszM1Jq2vK1ycJENc0mL3XPuXf/LIlT8wd RKYC4bFgPKD26RUMRmxT0CrB0d3i0fI= X-Google-Smtp-Source: ACJfBotpsjZMCNkQsadPXHc3rW92zCRZIzg5R7lBv9af3Oo1X/ODawnKkmRN7ZH9K+MaxrIwShXw9Q== X-Received: by 10.237.53.2 with SMTP id a2mr1998891qte.5.1513019245334; Mon, 11 Dec 2017 11:07:25 -0800 (PST) From: Adhemerval Zanella To: libc-alpha@sourceware.org Subject: [PATCH 10/19] nptl: ia64: Fix Race conditions in pthread cancellation (BZ#12683) Date: Mon, 11 Dec 2017 17:06:54 -0200 Message-Id: <1513019223-7603-11-git-send-email-adhemerval.zanella@linaro.org> In-Reply-To: <1513019223-7603-1-git-send-email-adhemerval.zanella@linaro.org> References: <1513019223-7603-1-git-send-email-adhemerval.zanella@linaro.org> This patch adds the s390 modifications required for the BZ#12683. It basically adds the required ucontext_get_pc function. a workaround for mismatched sigcontext::sa_flags defiition between kernel and GLIBC (tracked by BZ#21634), and an arch specific syscall_cancel implementation. IA64 requires an arch-specific syscall_cancel implemetantion because {INLINE,INTERNAL}_SYSCALL is implemented by branching to a gate DSO (similar to i386) which renders the pointer comparison in SIGCANCEL handler wrong. This incurs in performance penalty due the use of a break instruction insteaf of a eds one, however cancellable syscalls should potentially incur in syscalls blocking. Checked with a ia64-linux-gnu build with run-tests-built=no. * sysdeps/unix/sysv/linux/ia64/sigcontextinfo.h (ucontext_get_pc, ucontext_get_mask): New functions. * sysdeps/unix/sysv/linux/ia64/syscall_cancel.S: New file. Signed-off-by: Adhemerval Zanella --- ChangeLog | 3 + sysdeps/unix/sysv/linux/ia64/sigcontextinfo.h | 24 +++++++ sysdeps/unix/sysv/linux/ia64/syscall_cancel.S | 94 +++++++++++++++++++++++++++ 3 files changed, 121 insertions(+) create mode 100644 sysdeps/unix/sysv/linux/ia64/syscall_cancel.S diff --git a/sysdeps/unix/sysv/linux/ia64/sigcontextinfo.h b/sysdeps/unix/sysv/linux/ia64/sigcontextinfo.h index 37a6190..927cb3c 100644 --- a/sysdeps/unix/sysv/linux/ia64/sigcontextinfo.h +++ b/sysdeps/unix/sysv/linux/ia64/sigcontextinfo.h @@ -15,6 +15,11 @@ License along with the GNU C Library; if not, see . */ +#ifndef _SIGCONTEXTINFO_H +#define _SIGCONTEXTINFO_H + +#include + #define SIGCONTEXT siginfo_t *_si, struct sigcontext * #define SIGCONTEXT_EXTRA_ARGS _si, #define GET_PC(ctx) ((ctx)->sc_ip) @@ -23,3 +28,22 @@ #define CALL_SIGHANDLER(handler, signo, ctx) \ (handler)((signo), SIGCONTEXT_EXTRA_ARGS (ctx)) + +/* Different that other architectures, SPARC pass a sigcontext_t struct + in third argument for sa_sigaction handler with SA_SIGINFO. */ +static inline uintptr_t +ucontext_get_pc (const struct sigcontext *sigctx) +{ + return sigctx->sc_ip; +} + +static inline sigset_t * +ucontext_get_mask (const struct sigcontext *sigctx) +{ + /* IA64 sigcontext::sa_mask is a sigset_t since Linux 2.6.12 (initial + git repository build). */ + return (sigset_t *) &sigctx->sc_mask; +} +#define UCONTEXT_SIGMASK(ctx) ucontext_get_mask (ctx) + +#endif /* _SIGCONTEXTINFO_H */ diff --git a/sysdeps/unix/sysv/linux/ia64/syscall_cancel.S b/sysdeps/unix/sysv/linux/ia64/syscall_cancel.S new file mode 100644 index 0000000..9c6c9d3 --- /dev/null +++ b/sysdeps/unix/sysv/linux/ia64/syscall_cancel.S @@ -0,0 +1,94 @@ +/* Cancellable syscall wrapper. Linux/IA64 version. + Copyright (C) 2017 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, see + . */ + +#include +#undef ret + +/* long int __syscall_cancel_arch (int *cancelhandling, long int nr, + long int arg1, long int arg2, long int arg3, + long int arg4, long int arg5, long int arg6) +*/ + +ENTRY (__syscall_cancel_arch) + .prologue 14, 40 + .mmi + .save ar.pfs, r41 + alloc r41 = ar.pfs, 8, 4, 8, 0 + .vframe r42 + mov r42 = r12 + .save rp, r40 + mov r40 = b0 + .body + ;; + + .global __syscall_cancel_arch_start + .type __syscall_cancel_arch_start,@function +__syscall_cancel_arch_start: + + ;; + .mmi + nop 0 + ld4.acq r14 = [r32] + nop 0 + ;; + .mib + nop 0 + tbit.z p6, p7 = r14, 2 + .pred.safe_across_calls p1-p63 + (p7) br.call.dpnt.many b0 = __syscall_do_cancel# + .pred.safe_across_calls p1-p5,p16-p63 + ;; + .mmi + mov r15 = r33 + mov r49 = r39 + mov r48 = r38 + .mmi + mov r47 = r37 + mov r46 = r36 + mov r45 = r35 + ;; + .mmi + nop 0 + mov r44 = r34 + nop 0 + ;; + break 0x100000 + ;; + + .global __syscall_cancel_arch_end + .type __syscall_cancel_arch_end,@function +__syscall_cancel_arch_end: + + ;; + .mmi + cmp.ne p6, p7 = -1, r10 + nop 0 + mov ar.pfs = r41 + ;; + .mmi + nop 0 + (p7) sub r8 = r0, r8 + mov b0 = r40 + .mmb + nop 0 + .restore sp + mov r12 = r42 + br.ret.sptk.many b0 + +END (__syscall_cancel_arch) +libc_hidden_def (__syscall_cancel_arch)