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=-17.3 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, USER_AGENT_SANE_1 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 3FC3BC4361B for ; Sun, 20 Dec 2020 14:23:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0348522D0A for ; Sun, 20 Dec 2020 14:23:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727610AbgLTOXM (ORCPT ); Sun, 20 Dec 2020 09:23:12 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:21610 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727489AbgLTOXL (ORCPT ); Sun, 20 Dec 2020 09:23:11 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1608474103; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=MDbwUf+8XstD8OivjaozAkwTO9Z6ZWRHeP6xHB5dtGU=; b=VrdcPmP1TtNr7vWPJmSNnj9M2deMy1VLXmRdyzyCATJpF+9ZO1n0w9v5eXcCe1VUmglg8Y VIst4UCorv7XC9RDlL+dVdK8dXiLPtx6NZscHlOkJP/uAtJUOBvtfeODILav+e64MNhdnE ayGqUhJXHsaSh1PJRLMhM2ise1kfDt4= 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-227-QteUgzOOPxa2LRiPmB4QGg-1; Sun, 20 Dec 2020 09:21:41 -0500 X-MC-Unique: QteUgzOOPxa2LRiPmB4QGg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 89FA815720; Sun, 20 Dec 2020 14:21:39 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.40.192.9]) by smtp.corp.redhat.com (Postfix) with SMTP id 9958619715; Sun, 20 Dec 2020 14:21:36 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Sun, 20 Dec 2020 15:21:39 +0100 (CET) Date: Sun, 20 Dec 2020 15:21:35 +0100 From: Oleg Nesterov To: Leesoo Ahn Cc: linux-kernel@vger.kernel.org, Leesoo Ahn , Christian Brauner , "Eric W. Biederman" , Jens Axboe , Peter Collingbourne , Zhiqiang Liu Subject: Re: [PATCH] signal: Don't init struct kernel_siginfo fields to zero again Message-ID: <20201220142134.GB16470@redhat.com> References: <20201220074555.12655-1-lsahn@ooseel.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201220074555.12655-1-lsahn@ooseel.net> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/20, Leesoo Ahn wrote: > > clear_siginfo() is responsible for clearing struct kernel_siginfo object. > It's obvious that manually initializing those fields is needless as > a commit[1] explains why the function introduced and its guarantee that > all bits in the struct are cleared after it. > > [1]: commit 8c5dbf2ae00b ("signal: Introduce clear_siginfo") > > Signed-off-by: Leesoo Ahn Acked-by: Oleg Nesterov > --- > kernel/signal.c | 21 --------------------- > 1 file changed, 21 deletions(-) > > diff --git a/kernel/signal.c b/kernel/signal.c > index 5736c55aaa1a..8f49fa3ade33 100644 > --- a/kernel/signal.c > +++ b/kernel/signal.c > @@ -603,10 +603,7 @@ static void collect_signal(int sig, struct sigpending *list, kernel_siginfo_t *i > */ > clear_siginfo(info); > info->si_signo = sig; > - info->si_errno = 0; > info->si_code = SI_USER; > - info->si_pid = 0; > - info->si_uid = 0; > } > } > > @@ -1120,7 +1117,6 @@ static int __send_signal(int sig, struct kernel_siginfo *info, struct task_struc > case (unsigned long) SEND_SIG_NOINFO: > clear_siginfo(&q->info); > q->info.si_signo = sig; > - q->info.si_errno = 0; > q->info.si_code = SI_USER; > q->info.si_pid = task_tgid_nr_ns(current, > task_active_pid_ns(t)); > @@ -1133,10 +1129,7 @@ static int __send_signal(int sig, struct kernel_siginfo *info, struct task_struc > case (unsigned long) SEND_SIG_PRIV: > clear_siginfo(&q->info); > q->info.si_signo = sig; > - q->info.si_errno = 0; > q->info.si_code = SI_KERNEL; > - q->info.si_pid = 0; > - q->info.si_uid = 0; > break; > default: > copy_siginfo(&q->info, info); > @@ -1623,10 +1616,7 @@ void force_sig(int sig) > > clear_siginfo(&info); > info.si_signo = sig; > - info.si_errno = 0; > info.si_code = SI_KERNEL; > - info.si_pid = 0; > - info.si_uid = 0; > force_sig_info(&info); > } > EXPORT_SYMBOL(force_sig); > @@ -1659,7 +1649,6 @@ int force_sig_fault_to_task(int sig, int code, void __user *addr > > clear_siginfo(&info); > info.si_signo = sig; > - info.si_errno = 0; > info.si_code = code; > info.si_addr = addr; > #ifdef __ARCH_SI_TRAPNO > @@ -1691,7 +1680,6 @@ int send_sig_fault(int sig, int code, void __user *addr > > clear_siginfo(&info); > info.si_signo = sig; > - info.si_errno = 0; > info.si_code = code; > info.si_addr = addr; > #ifdef __ARCH_SI_TRAPNO > @@ -1712,7 +1700,6 @@ int force_sig_mceerr(int code, void __user *addr, short lsb) > WARN_ON((code != BUS_MCEERR_AO) && (code != BUS_MCEERR_AR)); > clear_siginfo(&info); > info.si_signo = SIGBUS; > - info.si_errno = 0; > info.si_code = code; > info.si_addr = addr; > info.si_addr_lsb = lsb; > @@ -1726,7 +1713,6 @@ int send_sig_mceerr(int code, void __user *addr, short lsb, struct task_struct * > WARN_ON((code != BUS_MCEERR_AO) && (code != BUS_MCEERR_AR)); > clear_siginfo(&info); > info.si_signo = SIGBUS; > - info.si_errno = 0; > info.si_code = code; > info.si_addr = addr; > info.si_addr_lsb = lsb; > @@ -1740,7 +1726,6 @@ int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper) > > clear_siginfo(&info); > info.si_signo = SIGSEGV; > - info.si_errno = 0; > info.si_code = SEGV_BNDERR; > info.si_addr = addr; > info.si_lower = lower; > @@ -1755,7 +1740,6 @@ int force_sig_pkuerr(void __user *addr, u32 pkey) > > clear_siginfo(&info); > info.si_signo = SIGSEGV; > - info.si_errno = 0; > info.si_code = SEGV_PKUERR; > info.si_addr = addr; > info.si_pkey = pkey; > @@ -1934,7 +1918,6 @@ bool do_notify_parent(struct task_struct *tsk, int sig) > > clear_siginfo(&info); > info.si_signo = sig; > - info.si_errno = 0; > /* > * We are under tasklist_lock here so our parent is tied to > * us and cannot change. > @@ -2033,7 +2016,6 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, > > clear_siginfo(&info); > info.si_signo = SIGCHLD; > - info.si_errno = 0; > /* > * see comment in do_notify_parent() about the following 4 lines > */ > @@ -2506,7 +2488,6 @@ static int ptrace_signal(int signr, kernel_siginfo_t *info) > if (signr != info->si_signo) { > clear_siginfo(info); > info->si_signo = signr; > - info->si_errno = 0; > info->si_code = SI_USER; > rcu_read_lock(); > info->si_pid = task_pid_vnr(current->parent); > @@ -3660,7 +3641,6 @@ static inline void prepare_kill_siginfo(int sig, struct kernel_siginfo *info) > { > clear_siginfo(info); > info->si_signo = sig; > - info->si_errno = 0; > info->si_code = SI_USER; > info->si_pid = task_tgid_vnr(current); > info->si_uid = from_kuid_munged(current_user_ns(), current_uid()); > @@ -3833,7 +3813,6 @@ static int do_tkill(pid_t tgid, pid_t pid, int sig) > > clear_siginfo(&info); > info.si_signo = sig; > - info.si_errno = 0; > info.si_code = SI_TKILL; > info.si_pid = task_tgid_vnr(current); > info.si_uid = from_kuid_munged(current_user_ns(), current_uid()); > -- > 2.26.2 >