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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F3A55F46C78 for ; Mon, 6 Apr 2026 19:55:36 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [127.0.0.1]) by lists.ozlabs.org (Postfix) with ESMTP id 4fqKnM3NXzz2ySS; Tue, 07 Apr 2026 05:55:35 +1000 (AEST) Authentication-Results: lists.ozlabs.org; arc=none smtp.remote-ip=148.163.158.5 ARC-Seal: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1775505335; cv=none; b=oQ7WWPicHC1ubh3vP1fAjrlb9hXiQ6Fr4YDgGq+0v7P6tXasDpwedUbeANKVa1h/Uq/IU7fdyMstlnHhx4AekE+Fk7+XvrL6epjY0RPiM5XOyTZFfW029suTlx9pc67JJQrrUyx2BybGaeSH4zj9hM8UJpBR3sB8BWs0mKRb7SqV1OG1dM8EPn0l6lAy2zNKP/+YK45SoCdT/vyVWW9AdI76Z5KdjO68UPe2iWvE5/8AiJkUiUBlTyGAJ3BDNhkjByBL7mkGwSvMSjk4YwtR0Ach1Caz31kWnJwyUMZiFniaKHc83ulNG6wkRGYJGTXLAfgb3xr0lWuKR2nwwkBLKw== ARC-Message-Signature: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1775505335; c=relaxed/relaxed; bh=0tUd9BeLjceswPNauAQU18mD/3V/V6pMUOu6B8z8WBs=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=MqG12grqFrrF5aS2w31pLirgC3FmsE3fYxqib062OWG19hfZ09KNbhyniPx+06E6xNJLbXFCUgrF8MJ8i6+xE37goxC4wqADI36pbvi7gPRqE/7yhiEmbCXu/XF2RhiRstiKf+/l8gLSdoa1efqM0iWoEvnECt454aaPXDo3b9DVuAKRm9O+N9x25G/0L+OBGiGUGzgMgjQUAQ7YBxLwYhuwZ0q2u7addUmmx2mzk1YRfgpaPnItMRNsws28mFCN/QqLGWblTRMQaYVoCZMWFI9lLZ+796plfBJzYvKB6Wxu3YZgEui1YW/hOOyt6gcIZtTyC5/rbYZwBWrXV7pZJw== ARC-Authentication-Results: i=1; lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com; dkim=pass (2048-bit key; unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256 header.s=pp1 header.b=bfM4DGIV; dkim-atps=neutral; spf=pass (client-ip=148.163.158.5; helo=mx0b-001b2d01.pphosted.com; envelope-from=aboorvad@linux.ibm.com; receiver=lists.ozlabs.org) smtp.mailfrom=linux.ibm.com Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256 header.s=pp1 header.b=bfM4DGIV; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.ibm.com (client-ip=148.163.158.5; helo=mx0b-001b2d01.pphosted.com; envelope-from=aboorvad@linux.ibm.com; receiver=lists.ozlabs.org) Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4fqKnL4JxSz2xHX for ; Tue, 07 Apr 2026 05:55:34 +1000 (AEST) Received: from pps.filterd (m0353725.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 636IYkVg3869782; Mon, 6 Apr 2026 19:55:25 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=pp1; bh=0tUd9B eLjceswPNauAQU18mD/3V/V6pMUOu6B8z8WBs=; b=bfM4DGIV53QLNQx7T4jaQS 4Pg6ErhfPTasfBBqCkrdELEZhTNe2rstNuZsSiVUj8e8hZJBdW8zxXTD5nFh9Hi4 zx4xi+KeegeP0zYSzuaAczCTe4xFT/4WLS+kMXxInnDmVJoMfeKpFs/xWmPhxDmi kqu91P2VNif0/jOtMfvsFqP4qvDcUk/3V3aahccH44YZcD/jD3hYfXQjHfDhL2OL 8mJRxotRDYovIHPgHuqFC3vTO7EeNq96JC4MXS3wW1+v8Gaek2Ojo5gx7buLiV8+ J3jQKDnPh8E4PaJKpq/HkuIXAg/WZKKyDDURI3osm4s6vAnR6UIdnRabkHYX1mWA == Received: from ppma12.dal12v.mail.ibm.com (dc.9e.1632.ip4.static.sl-reverse.com [50.22.158.220]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4das2bynf7-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 06 Apr 2026 19:55:24 +0000 (GMT) Received: from pps.filterd (ppma12.dal12v.mail.ibm.com [127.0.0.1]) by ppma12.dal12v.mail.ibm.com (8.18.1.2/8.18.1.2) with ESMTP id 636EvJsH018529; Mon, 6 Apr 2026 19:55:23 GMT Received: from smtprelay05.fra02v.mail.ibm.com ([9.218.2.225]) by ppma12.dal12v.mail.ibm.com (PPS) with ESMTPS id 4dbcysx32q-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 06 Apr 2026 19:55:23 +0000 Received: from smtpav05.fra02v.mail.ibm.com (smtpav05.fra02v.mail.ibm.com [10.20.54.104]) by smtprelay05.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 636JtKFl34537750 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 6 Apr 2026 19:55:20 GMT Received: from smtpav05.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E438C20043; Mon, 6 Apr 2026 19:55:19 +0000 (GMT) Received: from smtpav05.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4226E20040; Mon, 6 Apr 2026 19:55:17 +0000 (GMT) Received: from aboo.ibm.com (unknown [9.43.87.37]) by smtpav05.fra02v.mail.ibm.com (Postfix) with ESMTP; Mon, 6 Apr 2026 19:55:17 +0000 (GMT) Message-ID: Subject: Re: [PATCH v2 1/2] powerpc/kdump: fix KASAN sanitization flag for core_$(BITS).o From: Aboorva Devarajan To: Sourabh Jain , linuxppc-dev@lists.ozlabs.org Cc: Venkat Rao Bagalkote , Aditya Gupta , Daniel Axtens , Hari Bathini , Madhavan Srinivasan , Michael Ellerman , Shivang Upadhyay , "Ritesh Harjani (IBM)" , Mahesh Salgaonkar , aboorvad@linux.ibm.com Date: Tue, 07 Apr 2026 01:25:16 +0530 In-Reply-To: <20260403190123.1383198-1-sourabhjain@linux.ibm.com> References: <20260403190123.1383198-1-sourabhjain@linux.ibm.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.3 (3.58.3-1.fc43) X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Proofpoint-ORIG-GUID: H7EsrUocxTZU86TPNp5260s1F0uaQNfo X-Proofpoint-GUID: R3LFBTfCDvSdoyB1M20XZOJRNFE2ZmBs X-Authority-Analysis: v=2.4 cv=U9qfzOru c=1 sm=1 tr=0 ts=69d40fac cx=c_pps a=bLidbwmWQ0KltjZqbj+ezA==:117 a=bLidbwmWQ0KltjZqbj+ezA==:17 a=IkcTkHD0fZMA:10 a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=V8glGbnc2Ofi9Qvn3v5h:22 a=VwQbUJbxAAAA:8 a=VnNF1IyMAAAA:8 a=JuTF4qcAAAAA:8 a=pGLkceISAAAA:8 a=ZSZbnnKFPOSW3gtc0DAA:9 a=QEXdDO2ut3YA:10 a=WlT8qwTXB_Kj6um4hl3b:22 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNDA2MDE5NCBTYWx0ZWRfX0PSIwCDSZuSV YsMfQARySkO8Ngk/XfizU31S71HkYJ36qBK0LCAXAVkksGUa7YORYc3piUWExhWQzFee5xjQR+E oIafnMYzvdoITVg3JSSt5/OMUjsedUHKvTOHydUJxUPdRka86BUTtl5l80hVV7gsVH6WOGPd8cy PcVaVqJKy3i97Xx2xQxY/7gA3eKKbBLLyP2ZmSboQ89NzdknfBNgTZHKRPaqY+efZScRM12ovZf 9FVwCBRHXUQLyBVxUVCC6T2NBE4uJYIdeV/H7cUqetXkicTnYNG9TYS0twvZIA2rVYFsDl4Wybm uF6IOob1Pse0W4GMCFN6bn46FlNwjMymrryHUX8j7qkO/hppFL7ge8Fd2zbW337j2Bmc78DsKhr Q7dwA5KKvt8O8okbwXcHGk3fSRuLtqPp6/13CzL++KZr1F9y/SPasJU35WUSpOa+mmbOaN6uKqE 92eF1kaSz+VeMVFY4GA== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-04-06_04,2026-04-03_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 malwarescore=0 clxscore=1015 adultscore=0 suspectscore=0 spamscore=0 priorityscore=1501 impostorscore=0 lowpriorityscore=0 phishscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2603050001 definitions=main-2604060194 On Sat, 2026-04-04 at 00:31 +0530, Sourabh Jain wrote: > KASAN instrumentation is intended to be disabled for the kexec core > code, but the existing Makefile entry misses the object suffix. As a > result, the flag is not applied correctly to core_$(BITS).o. >=20 > So when KASAN is enabled, kexec_copy_flush and copy_segments in > kexec/core_64.c are instrumented, which can result in accesses to > shadow memory via normal address translation paths. Since these run > with the MMU disabled, such accesses may trigger page faults > (bad_page_fault) that cannot be handled in the kdump path, ultimately > causing a hang and preventing the kdump kernel from booting. The same > is true for kexec as well, since the same functions are used there. >=20 > Update the entry to include the =E2=80=9C.o=E2=80=9D suffix so that KASAN > instrumentation is properly disabled for this object file. >=20 > Fixes: 2ab2d5794f14 ("powerpc/kasan: Disable address sanitization in > kexec paths") > Reported-by: Venkat Rao Bagalkote > Closes: > https://lore.kernel.org/all/1dee8891-8bcc-46b4-93f3-fc3a774abd5b@linux.ib= m.com/ > Cc: Aboorva Devarajan > Cc: Aditya Gupta > Cc: Daniel Axtens > Cc: Hari Bathini > Cc: Madhavan Srinivasan > Cc: Michael Ellerman > Cc: Shivang Upadhyay > Reviewed-by: Ritesh Harjani (IBM) > Tested-by: Venkat Rao Bagalkote > Acked-by: Mahesh Salgaonkar > Signed-off-by: Sourabh Jain > --- > Changelog: >=20 > v2: > - Add Reviewed-by, Acked-by and Tested-by tags > - No functional changes > =C2=A0 > =C2=A0v1: > =C2=A0 > https://lore.kernel.org/all/20260321053121.614022-1-sourabhjain@linux. > ibm.com/ > --- > =C2=A0arch/powerpc/kexec/Makefile | 2 +- > =C2=A01 file changed, 1 insertion(+), 1 deletion(-) >=20 > diff --git a/arch/powerpc/kexec/Makefile > b/arch/powerpc/kexec/Makefile > index 470eb0453e17..ec7a0eed75dc 100644 > --- a/arch/powerpc/kexec/Makefile > +++ b/arch/powerpc/kexec/Makefile > @@ -16,4 +16,4 @@ GCOV_PROFILE_core_$(BITS).o :=3D n > =C2=A0KCOV_INSTRUMENT_core_$(BITS).o :=3D n > =C2=A0UBSAN_SANITIZE_core_$(BITS).o :=3D n > =C2=A0KASAN_SANITIZE_core.o :=3D n > -KASAN_SANITIZE_core_$(BITS) :=3D n > +KASAN_SANITIZE_core_$(BITS).o :=3D n With both the patches applied, kexec completes successfully with KASAN enabled. Reviewed-by: Aboorva Devarajan Tested-by: Aboorva Devarajan Thanks, Aboorva