From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 333D13EDE6E; Mon, 6 Jul 2026 08:17:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783325832; cv=none; b=EXopdJlxeRBqscAh0GNclKUMtPHUfDueelIWrZW0La43c0oubx0nSFURGdWjs/tbthPEkq63hi7uV4HB7tVeWZk3ssCtd/58PtxVcahgBnXK+rkbuDxrZIlY6HdvDkrqZ7ii1cJPt2qe0rPW4l274eyZWFNDngTPJjQ9Ws+DMdE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783325832; c=relaxed/simple; bh=2gFskhsb6RmAA5VINJrK/A8SJPhRd6tZO5gS28To3ts=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=Uwquj7ZNECsM+RLjAtk6r2AXRRdFKarzGPCrn/1Hnf3G7w6d16wjhIQ/t+26H0PuwGzb7Zkzln0QX2iisu1TYgCodoYAYURO/sy5oU8dIGiS9zgwREEMUjXXwDqtGar4Nvfl0yP+RqhV1Ov8FjiCMLkxlwzEKMENvqlwKa3fnoU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=XfC9H2UV; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="XfC9H2UV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E7CF91F000E9; Mon, 6 Jul 2026 08:16:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783325820; bh=r7+ah1vbGAvQLsR+3yUG/Iv1avIrbLDskfWMmANIMpA=; h=From:To:Cc:Subject:In-Reply-To:References:Date; b=XfC9H2UVpNQGtHq/xKLEWuvy4dBFo+F8wnT4a3nMjIvGfHuzuoXWCWWpR3IRGACyX ddDWKGu9BP+PsJvxUDK2bd/p/KeWLd0czr6A1n2oiorGfYOAORf0VSj4p8BpzPNLGs Ks/289z7wkXWc1DnJ7LrjlkM5r3LLyPV2aysSVO7Va/BtZrxeY3rlf3iV2jR28XK6V xvP1325V2CnieiUAnTaDerFyvnvz3so5txLMmGU2XfJvoVLUklK5D8L7xrnfvcxkuk 3Zu/60IEr5IZRUAZ6W1jaKJhtWOhQgEXUqGG56v4UZ08TQLLk8BNUS0lXkVaayTddt u2lcP/zMPqcAw== From: Thomas Gleixner To: Michal =?utf-8?Q?Such=C3=A1nek?= , Peter Zijlstra Cc: Jonathan Corbet , Shuah Khan , Huacai Chen , WANG Xuerui , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Andy Lutomirski , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Andrew Donnellan , Mark Rutland , Michal =?utf-8?Q?Such=C3=A1nek?= , Arnd Bergmann , Jiaxun Yang , Ryan Roberts , Greg Kroah-Hartman , Mukesh Kumar Chaurasiya , Shrikanth Hegde , Zong Li , Nam Cao , Deepak Gupta , Lukas Gerlach , Rui Qi , Kees Cook , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org Subject: Re: [RFC] entry: Untangle the return value of syscall_enter_from_user_mode from syscall NR In-Reply-To: References: Date: Mon, 06 Jul 2026 10:16:57 +0200 Message-ID: <87ik6sjzwm.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=utf-8 Content-Transfer-Encoding: quoted-printable On Wed, Jul 01 2026 at 19:42, Michal Such=C3=A1nek wrote: >=20=20 > if (unlikely(work & SYSCALL_WORK_SYSCALL_TRACEPOINT)) > - syscall =3D trace_syscall_enter(regs, syscall); > + *syscall =3D trace_syscall_enter(regs, *syscall); >=20=20 > - syscall_enter_audit(regs, syscall); > + syscall_enter_audit(regs, *syscall); >=20=20 > - return ret ? : syscall; > + return 0; That breaks trace_syscall_enter() because the probes/BPF muck attached ot that can: 1) set the return code 2) set syscall to -1L That works correctly today, but with your sloppy hackery the low level x86 code falls into sys_ni_syscall() which sets the return code to -ENOSYS.