From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 983A8C433ED for ; Tue, 18 May 2021 20:40:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 76D4E6100A for ; Tue, 18 May 2021 20:40:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235718AbhERUmE (ORCPT ); Tue, 18 May 2021 16:42:04 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:37988 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234956AbhERUmE (ORCPT ); Tue, 18 May 2021 16:42:04 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1621370445; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type; bh=w69KpmnHPYVDfRCSyWWa/+3eoFxNzS1wuEoBHG1tW9A=; b=ESjJqyUYCS53SyriQZjBUz8ZQ95SfBKDRmpdYlSJsxt1nohxohcKg5rYrPycWYf1ekmHB1 is1PFRLPR0fb9xMk+X1cBWl3A9WDZ6is5ayWApOGDC5VVVee1I3e7S2fVw1mBOzZ2+nQ3Q vwlcJQGfM/b8CekO0xsEGPPvdgceHBQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-68-2cJUuQBfOz2tKyDeQ1lp1w-1; Tue, 18 May 2021 16:40:42 -0400 X-MC-Unique: 2cJUuQBfOz2tKyDeQ1lp1w-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 987C91007476 for ; Tue, 18 May 2021 20:40:41 +0000 (UTC) Received: from oldenburg.str.redhat.com (ovpn-112-137.ams2.redhat.com [10.36.112.137]) by smtp.corp.redhat.com (Postfix) with ESMTPS id F1D38BA6D for ; Tue, 18 May 2021 20:40:40 +0000 (UTC) From: Florian Weimer To: linux-man@vger.kernel.org Subject: [PATCH] sigalstack.2: Mention the need for separate signal stacks for threads Date: Tue, 18 May 2021 22:40:38 +0200 Message-ID: <87h7iz4vy1.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: linux-man@vger.kernel.org Signed-off-by: Florian Weimer --- man2/sigaltstack.2 | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/man2/sigaltstack.2 b/man2/sigaltstack.2 index 53268ccbe..1510a98ab 100644 --- a/man2/sigaltstack.2 +++ b/man2/sigaltstack.2 @@ -54,7 +54,10 @@ alternate signal stack. An alternate signal stack is used during the execution of a signal handler if the establishment of that handler (see .BR sigaction (2)) -requested it. +requested it using the +.B SA_ONSTACK +flag. Each thread that can execute such signal handlers needs its own +separate alternate signal stack. .PP The normal sequence of events for using an alternate signal stack is the following: @@ -67,7 +70,7 @@ signal stack. Use .BR sigaltstack () to inform the system of the existence and -location of the alternate signal stack. +location of the alternate signal stack for the current thread. .TP 3. When establishing a signal handler using