From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2116) id 16B413857C70; Tue, 8 Dec 2020 18:18:27 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 16B413857C70 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Ian Lance Taylor To: gcc-cvs@gcc.gnu.org Subject: [gcc r11-5859] libgcc: block signals when releasing split-stack memory X-Act-Checkin: gcc X-Git-Author: Ian Lance Taylor X-Git-Refname: refs/heads/master X-Git-Oldrev: c0ed52d3e0044630b57a2145be78de199539d995 X-Git-Newrev: f41dd93ade24f22f8cd1863129ab20c821000134 Message-Id: <20201208181828.16B413857C70@sourceware.org> Date: Tue, 8 Dec 2020 18:18:27 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 08 Dec 2020 18:18:28 -0000 https://gcc.gnu.org/g:f41dd93ade24f22f8cd1863129ab20c821000134 commit r11-5859-gf41dd93ade24f22f8cd1863129ab20c821000134 Author: Ian Lance Taylor Date: Tue Dec 8 10:17:16 2020 -0800 libgcc: block signals when releasing split-stack memory * generic-morestack-thread.c (free_segments): Block signals during thread exit. Diff: --- libgcc/generic-morestack-thread.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/libgcc/generic-morestack-thread.c b/libgcc/generic-morestack-thread.c index 83a65501272..fd391bb2e1f 100644 --- a/libgcc/generic-morestack-thread.c +++ b/libgcc/generic-morestack-thread.c @@ -38,6 +38,7 @@ see the files COPYING3 and COPYING.RUNTIME respectively. If not, see #ifndef inhibit_libc #include +#include #include #include "generic-morestack.h" @@ -54,6 +55,9 @@ extern int pthread_key_create (pthread_key_t *, void (*) (void *)) extern int pthread_setspecific (pthread_key_t, const void *) __attribute__ ((weak)); +extern int pthread_sigmask (int, const sigset_t *, sigset_t *) + __attribute__ ((weak)); + /* The key for the list of stack segments to free when the thread exits. This is created by pthread_key_create. */ @@ -70,6 +74,16 @@ static pthread_once_t create_key_once = PTHREAD_ONCE_INIT; static void free_segments (void* arg) { + /* We must block signals in case the signal handler tries to split + the stack. We leave them blocked while the thread exits. */ + if (pthread_sigmask) + { + sigset_t mask; + + sigfillset (&mask); + pthread_sigmask (SIG_BLOCK, &mask, NULL); + } + __morestack_release_segments ((struct stack_segment **) arg, 1); }