From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7AAAE47A88B for ; Wed, 26 Aug 2026 19:32:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787772750; cv=none; b=C5h7pOCGmwfQtQb0WyxHNN8l+teqEap35exJTJtUdBoVnRPjL9MYR64O8X1aLib1xyQmnZGG3b3aCDDkmcip8GZSAYqAl/veVGgnl4dln6fb3dKHOCbKTo+SK+HmvOuYo138n4dgSVFz6NUw2Usd7b3cjDYhEVbXOl0gzIEfIXc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787772750; c=relaxed/simple; bh=Kb3Dp+TRTQB7glv+fCQ1vb8ywX/zbwfVK/o4cL00Y0g=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ENjuf+LciZX8N6uveeZpP0s7gU94KPgpR6b9zb7JF5GETF7Fdetjnbqy/pvG0yCcfH30w9Brd0kLejqXrpBXSfF6htLUOE/RPvbxzGgTg2Py1sRt7norkqijrYFKosoVfb6+W+X8qj4Pik1AR3vOh2evTxWHKaYZclmbyHFv0Uo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=XwZsoxB/; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="XwZsoxB/" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1787772735; 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=Kb3Dp+TRTQB7glv+fCQ1vb8ywX/zbwfVK/o4cL00Y0g=; b=XwZsoxB/jWGwSilyihjjYjTkqB9Mnwn3ff8jR6reQErBzNhsf3x5LBt2yCZsVys8gS8EKH HwGeNrNjMgTDuB9ZFjjDFVjHsI8F/4RqNpKqgkJcMCQjGtiEplzdF3ydu2J/vHS3DOAvkD C3QdVCBiQdUp9hLB6NaHiu91CEK2LaI= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-193-L99-wfWdNueij3QyzrmY_A-1; Wed, 26 Aug 2026 15:32:14 -0400 X-MC-Unique: L99-wfWdNueij3QyzrmY_A-1 X-Mimecast-MFC-AGG-ID: L99-wfWdNueij3QyzrmY_A_1787772731 Received: from mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.95]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id E8591195411B; Wed, 26 Aug 2026 19:32:10 +0000 (UTC) Received: from fedora (unknown [10.44.48.90]) by mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id E5684422; Wed, 26 Aug 2026 19:32:06 +0000 (UTC) Received: by fedora (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Wed, 26 Aug 2026 21:32:10 +0200 (CEST) Date: Wed, 26 Aug 2026 21:32:05 +0200 From: Oleg Nesterov To: Thomas Gleixner Cc: Frederic Weisbecker , Hyunwoo Kim , brauner@kernel.org, peterz@infradead.org, anna-maria@linutronix.de, ebiederm@xmission.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] signal: Use list_del_init_careful() in flush_sigqueue() Message-ID: References: <875x10hrkt.ffs@fw13> <8733w3j1i1.ffs@fw13> <87pkz6gms6.ffs@fw13> <87fr02gegn.ffs@fw13> <87zey8g05g.ffs@fw13> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87zey8g05g.ffs@fw13> X-Scanned-By: MIMEDefang 3.6 on 10.30.177.95 Thomas, I am already sleeping, but let me ask anyway On 08/26, Thomas Gleixner wrote: > > On Wed, Aug 26 2026 at 11:36, Oleg Nesterov wrote: > > > > So. With this change release_task()->flush_sigqueue(&old_leader->pending) > > can still race with posixtimer_send_sigqueue(), but it will do nothing. > > > > But it also does "nothing" if tmr->sigq is already pending (!list_empty) > > so I am starting to think about the change below again... > > Sure, but that's an orthogonal optimization once we fixed the exec() > mess :) I am almost sure I missed something again. But I thought that this "optimization" can also fix the exec() mess we discuss in this thread? No? Oleg.