From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) (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 1B5394C81; Fri, 31 Oct 2025 01:18:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=150.107.74.76 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761873502; cv=none; b=hM44bkb7miVETdzw3imDeOeIcIS6HL28doLV1LcVCb3Qwz7sPLuVEwbgXQD0YT1HNDGO9G0J04SIVtLBicEFjGM1iQCkQPz6nBVkiQZ6iyxhG7wz21kWXBgOXMEjxwU2G1g2CU0xuDlUfRnG5SfnIgvfGFMzqTxyiGTtlGIi6Xg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761873502; c=relaxed/simple; bh=hXMrFcsWoZiW5tMzpdbWSGzUtGF/9ammpOK9a2U3Ow4=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Sc+eqBpNAV996OQWUMGWnMqkQ0NE93T00I5w/FrWGruF20gAab1CCyo4CIkyFFTMKVnaeqHz7NrRQ6qqN8+aUo62l/4d6BkMeDsmqCO+SoX4wh3KYmuitkjEVZha7GkIzHEgyFgXbUBGAoZp2M4eOFybzdvcz5g2wciCGfiJu54= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=canb.auug.org.au; spf=pass smtp.mailfrom=canb.auug.org.au; dkim=pass (2048-bit key) header.d=canb.auug.org.au header.i=@canb.auug.org.au header.b=eAcaz765; arc=none smtp.client-ip=150.107.74.76 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=canb.auug.org.au Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=canb.auug.org.au Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=canb.auug.org.au header.i=@canb.auug.org.au header.b="eAcaz765" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canb.auug.org.au; s=202503; t=1761873493; bh=EnBz2xZ8wY++5A4DWATyj5lK5khc0mXCazXN4NiHVWY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=eAcaz765Wj3yx6dGSXxWVQuf3SQabeZcg5q5GAjbaBPl4k0DhFbH9U3AtENTMrtXA RxZmMy44rCOLrjQeoz6gOqfdUBo9jWQB9xFWKMnJsCO7CzddWVoAucaxlyWIcs5E/X eeohw2j9DL5s9gZClN9WrxEbasRJ4MQw2g6Bia7QQEBp3ktJvUS2P7XyUjsrglQONw hio3wl6VfEJP6ZccqOzAVxJ9hT/sLZQSfDIluktxo/KcBe+J8Fad6Okfixl//I+Vc7 2bl+Zm2OTHLdLqpOAHd6Jus+3/ASpM1EVrgfw4hkQCAQFYoewUOKRIoBLWxIBQTg21 qE4kpKDUJ4/jw== Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange secp256r1 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mail.ozlabs.org (Postfix) with ESMTPSA id 4cyNQY2PsKz4w9V; Fri, 31 Oct 2025 12:18:13 +1100 (AEDT) Date: Fri, 31 Oct 2025 12:18:12 +1100 From: Stephen Rothwell To: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Peter Zijlstra Cc: Linux Kernel Mailing List , Linux Next Mailing List Subject: Re: linux-next: build failure after merge of the tip tree Message-ID: <20251031121812.1db72425@canb.auug.org.au> In-Reply-To: <20251031120243.4394e6a8@canb.auug.org.au> References: <20251031120243.4394e6a8@canb.auug.org.au> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/+uRBJiK6h8/FNj=F3ab9OgG"; protocol="application/pgp-signature"; micalg=pgp-sha256 --Sig_/+uRBJiK6h8/FNj=F3ab9OgG Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Hi all, On Fri, 31 Oct 2025 12:02:43 +1100 Stephen Rothwell = wrote: > > After merging the tip tree, today's linux-next build (arm64 defconfig) > failed like this: >=20 > arch/arm64/kernel/entry-common.c: In function 'arm64_exit_to_user_mode': > arch/arm64/kernel/entry-common.c:103:9: error: implicit declaration of fu= nction 'exit_to_user_mode_prepare'; did you mean 'arch_exit_to_user_mode_pr= epare'? [-Wimplicit-function-declaration] > 103 | exit_to_user_mode_prepare(regs); > | ^~~~~~~~~~~~~~~~~~~~~~~~~ > | arch_exit_to_user_mode_prepare > In file included from arch/arm64/include/asm/current.h:5, > from include/linux/sched.h:12, > from include/linux/context_tracking.h:5, > from include/linux/irq-entry-common.h:5, > from kernel/entry/common.c:3: > kernel/entry/common.c: In function 'exit_to_user_mode_loop': > kernel/entry/common.c:77:29: error: implicit declaration of function 'rse= q_exit_to_user_mode_restart'; did you mean 'arch_exit_to_user_mode_prepare'= ? [-Wimplicit-function-declaration] > 77 | if (likely(!rseq_exit_to_user_mode_restart(regs, = ti_work))) > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > include/linux/compiler.h:76:45: note: in definition of macro 'likely' > 76 | # define likely(x) __builtin_expect(!!(x), 1) > | ^ >=20 > Caused by commit >=20 > d58930640310 ("entry: Split up exit_to_user_mode_prepare()") >=20 > and maybe following ones. >=20 > I have reverted these commits for today: >=20 > 69c8e3d16105 ("rseq: Switch to TIF_RSEQ if supported") > 1b3dd1c538a8 ("rseq: Split up rseq_exit_to_user_mode()") > d58930640310 ("entry: Split up exit_to_user_mode_prepare()") I also had to revert 84eeeb002035 ("rseq: Switch to fast path processing on exit to user") --=20 Cheers, Stephen Rothwell --Sig_/+uRBJiK6h8/FNj=F3ab9OgG Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEENIC96giZ81tWdLgKAVBC80lX0GwFAmkEDlQACgkQAVBC80lX 0Gzh7wf/ZbDgcyXwu5FQYhfZpWwEok9NUa8ezGcQ3p2/WliPo0x2TFcz//yk7JqH 9/TmBqdUo0C90PSEddCNwdBreeOhve+U+j0WhodNTZTw7j843nfI/LEOuLI6qkls zI6tI0+/VH/a+tSB7sFS+LzKoK9tGkVgUitePwDEj7Ax5l9oU6UUnSbGRz+Hh2cB RsliRjZquZboPDdayUVQ++Wk4mpn8JkmfvEbRr7iwFRmmrplyjmTCBUgaEN79/Gv R5rUBX23/fcoBoBsMWSPo6x+QybGzaRYt+1QwGnTMwZJmVkYUcxyA7L9oolApqhG bI5Fs28idY+JdFAbXf4Ez9eg+k5yCw== =c2C5 -----END PGP SIGNATURE----- --Sig_/+uRBJiK6h8/FNj=F3ab9OgG--