From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) (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 8D00740FDAA for ; Thu, 9 Jul 2026 11:13:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.180.131 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783595588; cv=none; b=qOG3GeNV7f2/+PuJrAWw0QQ1jLRelNscs9BTbO1/GO4iNivYABes+1UMlMLsy8vk1bXhxI437qxz1FaztTLo8tu/brN6pYN0c4P6KVW7fuAl8HOzpyYM0U5sfcsoazWZMl1MeM06iazvjVMq3/nwIuU5QExipqEIUj2TzVMb7to= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783595588; c=relaxed/simple; bh=HqXh4BfYQkZLyAofgdtRXqw9mAcQUWbFiU48fKsf49U=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Izl91W+p4p/RdPICEiSYwn84UtiqwSCqCOrO7vuqrdZquo5F/9JcPgrLnsRSfUFOiQ5hPLPQDdzFN64dqV7v0JntLz9kHK0sJE6m235LqB0UYA/wixApw9GlFgBNqDMmjlQH5LFGi3X/FB9CHVpvcGxELde1d2Q2YX5XurSTwaQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com; spf=pass smtp.mailfrom=oss.qualcomm.com; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b=jqvWJK8P; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b=iG0CDJi3; arc=none smtp.client-ip=205.220.180.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b="jqvWJK8P"; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b="iG0CDJi3" Received: from pps.filterd (m0279869.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 669B03vW1620682 for ; Thu, 9 Jul 2026 11:13:03 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qualcomm.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=qcppdkim1; bh= Tx1kSZXz579iItxHsi1/8Nt3maK8vpLohSpfVXF4Ysw=; b=jqvWJK8PLEi8s+Po PkAhOcF1EZ0TGn8umnL5kgryJ/tFquXm2xFzKz63mEvAAckXJG2v/bBhmyd/J+vv w606gHPQkOOhu8auM9bbQnd68PLYN5DhMVRn/TQO3SYM9ZXEOEAB8F2FTaHvyyzL /gj6GXZOaZ7Kqn5MccKMlGU9Y/8NaD7WUS1XOInbClq4x0wSv71WFJfHopsmfL88 joRiOO1NBxKuiVXV4p/tSPunQ9pAf4nwUwhwVoGhXqa2d3YUXy3NiFuuL84Sr5z0 sFBM3VIfsHX5R32LvKrkWCid7sj7it6qPECFAQp6EaOHyXV68SwSVXRcZbVTi1ag vIF6OQ== Received: from mail-qt1-f198.google.com (mail-qt1-f198.google.com [209.85.160.198]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 4f9sqsbx0h-1 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NOT) for ; Thu, 09 Jul 2026 11:13:03 +0000 (GMT) Received: by mail-qt1-f198.google.com with SMTP id d75a77b69052e-51a8c689b5fso13213181cf.0 for ; Thu, 09 Jul 2026 04:13:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oss.qualcomm.com; s=google; t=1783595583; x=1784200383; darn=vger.kernel.org; h=content-transfer-encoding:content-type:in-reply-to:from:references :cc:to:content-language:subject:user-agent:mime-version:date :message-id:from:to:cc:subject:date:message-id:reply-to:content-type; bh=Tx1kSZXz579iItxHsi1/8Nt3maK8vpLohSpfVXF4Ysw=; b=iG0CDJi3fEdX0+CvpLHa3ZPfVRJBQiHYA56w/vMcyBgF2+hpy32q3CU1HZq6nPC6xy UmjDZFf4CwiqV+QRBUVkridGTJW9uiQzqQdFVGemCQ+fVOre4X736H4qF6HV/I/Mg0mm 4mQQgA3UOxLee/+tn5H8iVMGP5DDnyDMYlMIM9yoA1vaqRiHEh4xDXOiyTrPenIWL3Xv eEl3zNhexfGNgmBPVd+rnFNzwmYjP+AaruVL6dHO/2bvZ+hVBZIQCV8e7So3Wmx1wRIW WODuJ0vTVTLLQ2w4X1BNziAAkXp95D3RtzBpcq8BLOHS2Nfw+jtRug1n/63Y//6MSIFB fkwA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1783595583; x=1784200383; h=content-transfer-encoding:content-type:in-reply-to:from:references :cc:to:content-language:subject:user-agent:mime-version:date :message-id:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=Tx1kSZXz579iItxHsi1/8Nt3maK8vpLohSpfVXF4Ysw=; b=ZCq1y/j5K0mGWFLgqIaGgUEnOLrAZn6RlRdM7ErgKT7vukzaF3wTrDOcmjWAVJW8Ml c/H25UX+umN2k029e0TTiuMNgY/NIO+h1MICBuV8J4URLTwh9OdsPLoYBoG0W0s4OAk4 8QYMzqXOrXTq8A2Ir6kabMzVuJqdZH51YyEt6AQDoBrce29PtGtVtMOXOnGxeAFAfNng SucyMFU/iFLo9ABk43mtwvWjXkIxoIeM5pvphWOBWQMpg1w4x5RJx+/zvaehZKt4LhwA OyO6yPRCxwLDGdilHu1q8zteKR3owQrNMBS+NTOvsS6hyuC2dblaFvw917MvL4EE6TWY bTTg== X-Forwarded-Encrypted: i=1; AHgh+RqwOfY268YHnU2ZLcIm3LnRCT/Fa1og8ujNU/r/rmBGX05WxQoyrfhRprx05quChtVTPBn1gMfwsgPz9Q==@vger.kernel.org X-Gm-Message-State: AOJu0YwKALJJbSaYI4JrCzo96sSze6W6Y1cNfGYKMaDCAlERRIXhR0zH TixiGCvBNgL/c6+31BVnBqWJKt/eEZG5riE5MS9DTRPnTgkrYaelFtjJVvcmM0cjeBpgWqVhbsA Tj9HHUrUvgSmSECu7e14TYbPUgMcalPJ65N3ZWzFryuBQECuKDqi97IZiiqDKcTZUjA== X-Gm-Gg: AfdE7ck1jwd1yBm8xhJRqjZbGwKqfwz4Fi47sQournoRqL2JM+KDi9JMY2lBqvDFVDT 9yT5nV0CqQ0l88rmmmU+G3MWrSm5IOkmsj4VEQYJ6moRmOgBRMBTLfVfYpsF2uGCyyr9kfXCOYX 58+NAaAEpaTNt8CLqlK8zcMz9KTuSX1ebL/7mgYKiaSh2aSo+CBYXRjPKm45AqqnVvy2QDkRxDv uI3Hti772VXIb3PkH4BY2yER+ATmk0u8gnp9AYA1Io2m/c/hkqhSp2QhrOam50bwbF64qchEJRl 2oo8HNU0FbFZ1C4bXexPc999p8UkGchLqkWh08zsH9hISsBaaFqiMMoB3mF8veXi9W4EGsBAg37 n9+1cEyPvPFxDHUyRStqA3u2qb2mGK31NrlGPjRzQbaOvqMpAJu/Cr7t2JarmlQ== X-Received: by 2002:ac8:7d14:0:b0:517:61d5:2f7b with SMTP id d75a77b69052e-51c8b4d596amr63974311cf.56.1783595582872; Thu, 09 Jul 2026 04:13:02 -0700 (PDT) X-Received: by 2002:ac8:7d14:0:b0:517:61d5:2f7b with SMTP id d75a77b69052e-51c8b4d596amr63973951cf.56.1783595582395; Thu, 09 Jul 2026 04:13:02 -0700 (PDT) Received: from [192.168.69.219] (88-187-86-199.subs.proxad.net. [88.187.86.199]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-47aa0f213e8sm48543085f8f.34.2026.07.09.04.12.58 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 09 Jul 2026 04:13:01 -0700 (PDT) Message-ID: <835e2f62-3b66-45d4-a614-dc2198a715ad@oss.qualcomm.com> Date: Thu, 9 Jul 2026 13:12:57 +0200 Precedence: bulk X-Mailing-List: linux-alpha@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [patch 01/18] powerpc: Move stack randomization after syscall_enter_from_user_mode() Content-Language: en-US To: Thomas Gleixner , LKML Cc: Peter Zijlstra , Michael Ellerman , Shrikanth Hegde , linuxppc-dev@lists.ozlabs.org, Kees Cook , Huacai Chen , loongarch@lists.linux.dev, Paul Walmsley , Palmer Dabbelt , linux-riscv@lists.infradead.org, Sven Schnelle , linux-s390@vger.kernel.org, x86@kernel.org, Mark Rutland , Jinjie Ruan , Andy Lutomirski , Oleg Nesterov , Richard Henderson , Russell King , Catalin Marinas , Guo Ren , Geert Uytterhoeven , Thomas Bogendoerfer , Helge Deller , Yoshinori Sato , Richard Weinberger , Chris Zankel , linux-arm-kernel@lists.infradead.org, linux-alpha@vger.kernel.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linux-sh@vger.kernel.org, linux-um@lists.infradead.org, Arnd Bergmann , Vineet Gupta , Will Deacon , Brian Cain , Michal Simek , Dinh Nguyen , "David S. Miller" , Andreas Larsson , linux-snps-arc@lists.infradead.org, linux-hexagon@vger.kernel.org, linux-openrisc@vger.kernel.org, sparclinux@vger.kernel.org, linux-arch@vger.kernel.org, =?UTF-8?Q?Michal_Such=C3=A1nek?= , Jonathan Corbet , linux-doc@vger.kernel.org References: <20260707181957.433213175@kernel.org> <20260707190253.718191130@kernel.org> From: =?UTF-8?Q?Philippe_Mathieu-Daud=C3=A9?= In-Reply-To: <20260707190253.718191130@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Proofpoint-Spam-Info: AW1haW4tMjYwNzA5MDEwOCBTYWx0ZWRfXxGIdCI59PDQb 8lazPtaNLxPA4o7n3wagRaGiwoUF4XpkQwuqp7FbCSJ+vGKcyjH+TI7UJBLcKOb4MdsTHg2oVIz jh/IXAwdUcQu2zCcpKFB23WJMGe6jrk= X-Proofpoint-GUID: yri4SZtncjH5hx_yIulLEX0SWSP9bJXT X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNzA5MDEwOCBTYWx0ZWRfX5y+3xW+0b6Wp YfKOha+XTaDMjvw3rhApR2Wu+OnBV6W1Ui1Cx3/o3/wg7NxDCbZmSnUMbBr7apUhNBNi7PaXW+6 jfdbenFcAQhuQL/os+iSso3H3W6orZUxBK18/VCrcy15hbBFuNNQUBkvPFNinMuNVR8mPLXj2qf Ca5fDyg1D50vbEzi2SDcEzVYVl8Vp47frKh9ZSc5+EfAYZxFlGgYOoOORU70puUjnF5itnmwtBb JkXBsgxGONf03CWRzOGqnREcjDACRle3gJckMmSCGCmHOfxdNHyzcjBbXjM+pW+JvglqNHgEPMl 9qP0fqfFmiILSZm/73po9fUME1yBgq1FpBtwW7C8vRSa3f3Y9fwTFcK6HHRZUiYyu0STXGOp2eE oqBXevnNXoQWdV8FjmiydheOHAtaOy25l+oWVhUtaHEJlusFIqhzU4WBCjG9aReKlpM8OpdO4rB D4FQkVNbUa77SeL+J7Q== X-Authority-Analysis: v=2.4 cv=Sv2gLvO0 c=1 sm=1 tr=0 ts=6a4f823f cx=c_pps a=mPf7EqFMSY9/WdsSgAYMbA==:117 a=4s3hRJSeHn4rkQlkrse1kQ==:17 a=IkcTkHD0fZMA:10 a=RAioF0-LDSMA:10 a=M51BFTxLslgA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=_glEPmIy2e8OvE2BGh3C:22 a=VwQbUJbxAAAA:8 a=VnNF1IyMAAAA:8 a=voM4FWlXAAAA:8 a=EUspDBNiAAAA:8 a=63ny2n9c4_t8xnV3ltYA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=dawVfQjAaf238kedN5IG:22 a=IC2XNlieTeVoXbcui8wp:22 X-Proofpoint-ORIG-GUID: yri4SZtncjH5hx_yIulLEX0SWSP9bJXT X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-07-09_02,2026-07-09_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 adultscore=0 priorityscore=1501 suspectscore=0 malwarescore=0 impostorscore=0 lowpriorityscore=0 clxscore=1011 bulkscore=0 phishscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2607090108 On 7/7/26 21:05, Thomas Gleixner wrote: > add_random_kstack_offset() is invoked before syscall_enter_from_user_mode() > establishes state. That's wrong because add_random_kstack_offset() calls > into instrumentable code. > > Move it after syscall_enter_from_user_mode() to ensure that state is > correctly established. > > Signed-off-by: Thomas Gleixner > Cc: Michael Ellerman > Cc: Shrikanth Hegde > Cc: linuxppc-dev@lists.ozlabs.org > --- > arch/powerpc/kernel/syscall.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > --- a/arch/powerpc/kernel/syscall.c > +++ b/arch/powerpc/kernel/syscall.c > @@ -19,8 +19,8 @@ notrace long system_call_exception(struc > long ret; > syscall_fn f; > > - add_random_kstack_offset(); > r0 = syscall_enter_from_user_mode(regs, r0); > + add_random_kstack_offset(); > > if (unlikely(r0 >= NR_syscalls)) { > if (unlikely(trap_is_unsupported_scv(regs))) { > Reviewed-by: Philippe Mathieu-Daudé