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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id C7CABD6C2B8 for ; Tue, 19 Nov 2024 23:39:10 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id ED3026B007B; Tue, 19 Nov 2024 18:39:09 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E82CC6B0082; Tue, 19 Nov 2024 18:39:09 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D232C6B0083; Tue, 19 Nov 2024 18:39:09 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id B47396B007B for ; Tue, 19 Nov 2024 18:39:09 -0500 (EST) Received: from smtpin30.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 2A6B640159 for ; Tue, 19 Nov 2024 23:39:09 +0000 (UTC) X-FDA: 82804461264.30.46B47AF Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf23.hostedemail.com (Postfix) with ESMTP id 198D314000B for ; Tue, 19 Nov 2024 23:38:33 +0000 (UTC) Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=VVwSwoDN; spf=pass (imf23.hostedemail.com: domain of jpoimboe@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=jpoimboe@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1732059365; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=kGolztqfWCjkr7VOZJBD9Z6/PyTHzreV2hqW7n+SJTU=; b=FFNLPJom+wn9Vht7g1741ViBeNJiAz0kExSUIV8HzgUErwZ428YwcpoP2V8QE/gPGb/Ae4 i4sglg7xi/oEUBy8CA+RHnbfdNBt/NrEkMI+LWhtIDnJCc/iiMJ+jh+2qJ1bq2y0fi/sz5 E2C3P+bdMDBbT7xnIWc8MMmFafvTcXI= ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=VVwSwoDN; spf=pass (imf23.hostedemail.com: domain of jpoimboe@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=jpoimboe@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1732059365; a=rsa-sha256; cv=none; b=pz4mAutywmH6eS61yb7yz2e80W7a/+/qj1A6eUM1S/8RslN6YXXdshuMyb9VFcB4FgIf6D r3JD3aTU29TWSdtFuRZSVazS7cIhP3jQCdMM9W25E2ZOYUpspuuDt0F38rBmy69rehlXQA 7U5ZC1FtbTG/pG47yj4/wtLlHU+x+as= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 094735C5754; Tue, 19 Nov 2024 23:38:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CB9B3C4CECF; Tue, 19 Nov 2024 23:39:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1732059545; bh=MJi3Fv2/1QvfWr/LiwMdd8vo0kHoZwkP7YNG7EQREfw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=VVwSwoDNu1TqMFW15ochzl8vEFTrIMSh2sexLA6XSHJ6qClpYzQmx/p8q0+V/ICdK QcTGJLa+7qQQT24Pg/o/ujB9zzGyzPLCSBycIpzaqRQmmnJgp8Bmm/Asv7c/PmvwiR hos+7CVCbsa55k1mc7GHNj+kA8fGiX99G6or+53fRDs2TtOHAVH3KebnDSKX5Yyt/J L+g+8gDhlLq8+G9Zy9kb7DEd1lIcrJQYolbFdsAW5Kbk4+ktaecXpi0xWOSpdFxTtO qI8NUGX2AHe6987zz7E0iSHgJlM8A9RAr5kj/WxICexja0uizSdnkHYiGVUCbPB9TB izDxUiUHmBDCA== Date: Tue, 19 Nov 2024 15:39:02 -0800 From: Josh Poimboeuf To: Valentin Schneider Cc: linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org, bpf@vger.kernel.org, x86@kernel.org, rcu@vger.kernel.org, linux-kselftest@vger.kernel.org, Steven Rostedt , Masami Hiramatsu , Jonathan Corbet , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Paolo Bonzini , Wanpeng Li , Vitaly Kuznetsov , Andy Lutomirski , Peter Zijlstra , Frederic Weisbecker , "Paul E. McKenney" , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Andrew Morton , Uladzislau Rezki , Christoph Hellwig , Lorenzo Stoakes , Jason Baron , Kees Cook , Sami Tolvanen , Ard Biesheuvel , Nicholas Piggin , Juerg Haefliger , Nicolas Saenz Julienne , "Kirill A. Shutemov" , Nadav Amit , Dan Carpenter , Chuang Wang , Yang Jihong , Petr Mladek , "Jason A. Donenfeld" , Song Liu , Julian Pidancet , Tom Lendacky , Dionna Glaze , Thomas =?utf-8?Q?Wei=C3=9Fschuh?= , Juri Lelli , Marcelo Tosatti , Yair Podemsky , Daniel Wagner , Petr Tesarik Subject: Re: [RFC PATCH v3 06/15] jump_label: Add forceful jump label type Message-ID: <20241119233902.kierxzg2aywpevqx@jpoimboe> References: <20241119153502.41361-1-vschneid@redhat.com> <20241119153502.41361-7-vschneid@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20241119153502.41361-7-vschneid@redhat.com> X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 198D314000B X-Stat-Signature: ahdcpcextgxjkwxsq1q7mxqwt88qasjn X-Rspam-User: X-HE-Tag: 1732059513-845166 X-HE-Meta: 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 wzU0oqns OpQojygitQ9GwxrED0RXw/JL+jeJFpKvWC3sVeINgK0gLRqCJGCfkk6GqsD6e0xQI7d0oAaJsre1OVuIWEYzT7HnuZSPgXUGrNXy30iZVV1AOnp5macK+5XYOtBkmI2yzFzIgXJ8E5YmSgQAOotGx0+OK8tuzJqQjWf8qrIAxaKETjT1/uEkDwcmUjIWypTVbGo7nzAns0w/UQBF3wN5j4bGb31k9kHVHOmqUfWm/Jy3atz0eJ/8n1Wl7JVuzBopi2nQcgh2PLmG7RwnKI1ToMQqx89CsYwwWj5dMsZapTohCUwu7Pt+oTpIGWRG9iHzSmNjriTv2E3lA/6BviY0Q9wRE7u9UbLIBPNPmDxI7BRwgW8VRfzZKbvBMJxS381Ifu6Oy5jF4COpQ6Ix3yCjD6du/ZzRBWyc8kDPVQjAaX0rjW5w= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Nov 19, 2024 at 04:34:53PM +0100, Valentin Schneider wrote: > Later commits will cause objtool to warn about non __ro_after_init static > keys being used in .noinstr sections in order to safely defer instruction > patching IPIs targeted at NOHZ_FULL CPUs. Don't we need similar checking for static calls? > Two such keys currently exist: mds_idle_clear and __sched_clock_stable, > which can both be modified at runtime. Not sure if feasible, but it sure would be a lot simpler to just make "no noinstr patching" a hard rule and then convert the above keys (or at least their noinstr-specific usage) to regular branches. Then "no noinstr patching" could be unilaterally enforced in text_poke_bp(). > diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h > index f5a2727ca4a9a..93e729545b941 100644 > --- a/include/linux/jump_label.h > +++ b/include/linux/jump_label.h > @@ -200,7 +200,8 @@ struct module; > #define JUMP_TYPE_FALSE 0UL > #define JUMP_TYPE_TRUE 1UL > #define JUMP_TYPE_LINKED 2UL > -#define JUMP_TYPE_MASK 3UL > +#define JUMP_TYPE_FORCEFUL 4UL JUMP_TYPE_NOINSTR_ALLOWED ? -- Josh