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 2DC0025B090 for ; Tue, 11 Aug 2026 04:59:03 +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=1786424345; cv=none; b=ccFKDo7u9MqUVTzFfNb1njCCjfh+55av7z2jpjzfnYUGmAc2zEwNePxoaDw4xnZW6Ll6jqRTw87FTHcpRYfoEU/k7ImNqKASy310IVAPmamo2LlGvBsGeVQRFr6PoJLRmYnqmKaThDADmzkDg5B0HRBD3tVA+XKGoGhuZJZ6Zlw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786424345; c=relaxed/simple; bh=Q/ckhMFHaG4jkOsTFPTJcttDH1WgXfHkeAbbxj6oSiw=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=KSO6ZxP89Rq9NLVTAcZXRLePstUaPqv80ThvXbFjmsF8uZwJVZrz6djzCrL/okaIub6RIjqd3Q8kMogS5OfxqKxu6vqG01mQnfpbj7g1PSjrbmAv6Lmz/KqdngED+UKHb5eI+tKTd6ck7tXsbOSBTjgoj9cf5sK9NRIqp5AnCto= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Gx25TPM0; 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="Gx25TPM0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A56CC1F000E9; Tue, 11 Aug 2026 04:59:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786424343; bh=VpmP0/V/f3nYUUeEX4OZFCdq3p8rw9FlptRhR3LAYSI=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=Gx25TPM0IQQuJ6Jt9Y43E/IQ6dVfolSgn1TdiB0fleynDN7oPw4YRKYboFKtHg0NQ EEX2jrLsp9v7+TlvUug+fBMqZzhfA83Cq+U5WQmeChknJ8ifPDPeSHFC2vPHKut2UZ Oi5FQmgTR3oHER0N/FVFX/uzLCzJWNlEVEBk5HWg04NUwj8iVsiv0pPd/GKgED8J+J fAzQaSFMzQfJRQGSIjIIR5aKOVyEbltgSQ0S6UrTEvqyMalGkxVwPmGllSBpk3iu5u WHMes8RO1gPlhZ941IvwOV5zoYeCQFQZyhmvNwqornTBtjS24uPtHpDWfPaJ93zjRF bXnBuiQdQYHNA== Message-ID: Date: Tue, 11 Aug 2026 06:58:57 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [BUG] powerpc: userspace processes crash in ld64.so.2 when running recent linux-next kernels To: Venkat Rao Bagalkote , Madhavan Srinivasan , Ritesh Harjani , linuxppc-dev , ajd@linux.ibm.com Cc: LKML , Christian Brauner , "linux-mm@kvack.org" References: <75419f88-eab9-444b-bf97-28a9765819ad@linux.ibm.com> <627c5c2f-a0b3-4fba-811f-7b4ed4c74dbb@linux.ibm.com> Content-Language: fr-FR From: "Christophe Leroy (CS GROUP)" In-Reply-To: <627c5c2f-a0b3-4fba-811f-7b4ed4c74dbb@linux.ibm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Le 11/08/2026 à 06:23, Venkat Rao Bagalkote a écrit : > > As part of debugging and suggested by Maddy, I reverted the following > commit: > >   263e5159e00a ("powerpc: Fix exit_flags field placement in pt_regs for > ptrace") > > and rebuilt/booted linux-next with only that change reverted. > > After booting the reverted kernel, I rebuilt the latest upstream kernel > using the same userspace and toolchain. The build completed > successfully and I did not observe any of the ld64.so.2 userspace > segfaults that were previously seen during kernel compilation. > > Kernel used for testing: > >   7.2.0-rc5-next-20260731-00001-g79d9c1ce90a9 > > Top of tree: > >   commit 79d9c1ce90a9873422ca4d6d0124a1d1c10a098c >   Revert "powerpc: Fix exit_flags field placement in pt_regs for ptrace" > > The upstream kernel build completed successfully: > >   INSTALL /lib/modules/7.2.0-rc7/kernel/net/openvswitch/vport-gre.ko >   DEPMOD  /lib/modules/7.2.0-rc7 >   INSTALL /boot > > Based on this testing, reverting commit 263e5159e00a appears to > eliminate the random userspace crashes observed during kernel builds, > suggesting that the issue may be related to that change. But commit 263e5159e00a fixes commit d7a6797e0bc1 ("powerpc: add exit_flags field in pt_regs"), by reverting commit 263e5159e00a you re-introduce other bugs. It's a bit difficult to see what commit 263e5159e00a is doing exactly, most of it is a revert of commit d7a6797e0bc1 but it does something instead. Need to see what remains with both commits applied. Christophe