From nobody Sat Jun 20 20:52:54 2026 Received: from pdx-out-003.esa.us-west-2.outbound.mail-perimeter.amazon.com (pdx-out-003.esa.us-west-2.outbound.mail-perimeter.amazon.com [44.246.68.102]) (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 310103242AB for ; Fri, 10 Apr 2026 01:16:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=44.246.68.102 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775783787; cv=none; b=jU6nkp1s1SrdvoVgozPmjOADxqSl4F7xvJG0JAPjhmJ9HeXthNBfUnUhCVu7qlLCbBT39jlFWmnLNJbAJSi9SxMsrUb+CxcBpH489zNuZztIwenz+EtorWFG+hFsd/IZ8hqDf4tiZVT2ZEVSFy9Dn2piFmNW4t9mdSP3sOh6Lqs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775783787; c=relaxed/simple; bh=8vsG2dQyU2S4u1cdR9mbEQKdSPq/SMHOFDyMhTFQjWU=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=bJ6hOV5VVnyp1rEef/6S1AiBVs5exr99gBZ9myAddMIlpuFjqZqbd7JexDAU5iwgRi5MCXSxqH88AbcisT0W81wcCp7kwagg22sLHO+x5graeghER4LV6b+Px443QRaDUBilwOc4LFtw3alYrGj8/EuYtrx5awzPnkggHB7pe9U= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.de; spf=pass smtp.mailfrom=amazon.de; dkim=pass (2048-bit key) header.d=amazon.de header.i=@amazon.de header.b=bgTyExWE; arc=none smtp.client-ip=44.246.68.102 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=amazon.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=amazon.de header.i=@amazon.de header.b="bgTyExWE" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.de; i=@amazon.de; q=dns/txt; s=amazoncorp2; t=1775783786; x=1807319786; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=y+ewA8RjY6nMAFwnoN35zZbuD8YUej+hPFsz1UPCe10=; b=bgTyExWEoWIQ77MgORzQgVFJte6lLW7P4Snnj7W6IUPbtCTBUBunUzJC w5nSUxiaevESGPGKDLJyMuPwKuQvHdx57r/p6cFKHQVRmiaHasGg25Zfs N55+j/fyK9yCx4cMolzMfPbEEp3XZ8ig+u+oFeInNUvX+NHny8Vqj/4gj zwqwrUSz5/T02EExoW+N8t2R/YSiNVhWQK3Ug7ZsBnjP4Jk64ppCcfd0k 6sv7v9MBBrxffb3YPwrOXo+fnjTSjIPQqCdykWXUq3Zsvy8nuBrMSgl8h uuBaMC2JLXlKRoLjdHUkRBod5VEJqOMQSDl57lBmMOKk0U7QJQbqdSOhe w==; X-CSE-ConnectionGUID: DHa5mPRbRGqTlrLccv9+iA== X-CSE-MsgGUID: Y8/JvhHsQZG4LF/ImZPAFg== X-IronPort-AV: E=Sophos;i="6.23,170,1770595200"; d="scan'208";a="16989540" Received: from ip-10-5-0-115.us-west-2.compute.internal (HELO smtpout.naws.us-west-2.prod.farcaster.email.amazon.dev) ([10.5.0.115]) by internal-pdx-out-003.esa.us-west-2.outbound.mail-perimeter.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Apr 2026 01:16:23 +0000 Received: from EX19MTAUWC001.ant.amazon.com [205.251.233.105:31699] by smtpin.naws.us-west-2.prod.farcaster.email.amazon.dev [10.0.3.82:2525] with esmtp (Farcaster) id 0218addb-e3f2-4ce7-89d0-f199987a9e46; Fri, 10 Apr 2026 01:16:23 +0000 (UTC) X-Farcaster-Flow-ID: 0218addb-e3f2-4ce7-89d0-f199987a9e46 Received: from EX19D001UWA001.ant.amazon.com (10.13.138.214) by EX19MTAUWC001.ant.amazon.com (10.250.64.174) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.2562.37; Fri, 10 Apr 2026 01:16:22 +0000 Received: from dev-dsk-epetron-1c-1d4d9719.eu-west-1.amazon.com (10.253.109.105) by EX19D001UWA001.ant.amazon.com (10.13.138.214) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.2562.37; Fri, 10 Apr 2026 01:16:20 +0000 From: Evangelos Petrongonas To: "Mike Rapoport (Microsoft)" , Alexander Graf CC: Evangelos Petrongonas , Pasha Tatashin , Pratyush Yadav , "Rob Herring" , Saravana Kannan , Changyuan Lyu , Andrew Morton , , , , Subject: [PATCH v2] kho: skip KHO for crash kernel Date: Fri, 10 Apr 2026 01:16:05 +0000 Message-ID: <20260410011609.1103-1-epetron@amazon.de> X-Mailer: git-send-email 2.47.3 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: EX19D043UWC001.ant.amazon.com (10.13.139.202) To EX19D001UWA001.ant.amazon.com (10.13.138.214) Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" kho_fill_kimage() unconditionally populates the kimage with KHO metadata for every kexec image type. When the image is a crash kernel, this can be problematic as the crash kernel can run in a small reserved region and the KHO scratch areas can sit outside it. The crash kernel then faults during kho_memory_init() when it tries phys_to_virt() on the KHO FDT address: Unable to handle kernel paging request at virtual address xxxxxxxx ... fdt_offset_ptr+... fdt_check_node_offset_+... fdt_first_property_offset+... fdt_get_property_namelen_+... fdt_getprop+... kho_memory_init+... mm_core_init+... start_kernel+... kho_locate_mem_hole() already skips KHO logic for KEXEC_TYPE_CRASH images, but kho_fill_kimage() was missing the same guard. As kho_fill_kimage() is the single point that populates image->kho.fdt and image->kho.scratch, fixing it here is sufficient for both arm64 and x86 as the FDT and boot_params path are bailing out when these fields are unset. Fixes: d7255959b69a ("kho: allow kexec load before KHO finalization") Signed-off-by: Evangelos Petrongonas Reviewed-by: Mike Rapoport (Microsoft) --- v2: Per Mike's review [1], move the guard into kho_fill_kimage() instead of patching the arch-level producers and consumers. This fixes both arm64 and x86 in one place and avoids redundant checks. Tested aga= in. Note regarding backporting The offending commit was deployed with 6.19. The only other supported kernel version with 6.18, unless I miss someting uses ``` if (!kho_out.finalized) ``` which in the case of crash kernel it shouldn't be finalised. [1] https://lore.kernel.org/all/ade2ExpM8ROXV-vy@kernel.org/ kernel/liveupdate/kexec_handover.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/liveupdate/kexec_handover.c b/kernel/liveupdate/kexec_h= andover.c index cc68a3692905..1029fe8778f2 100644 --- a/kernel/liveupdate/kexec_handover.c +++ b/kernel/liveupdate/kexec_handover.c @@ -1551,7 +1551,7 @@ int kho_fill_kimage(struct kimage *image) int err =3D 0; struct kexec_buf scratch; =20 - if (!kho_enable) + if (!kho_enable || image->type =3D=3D KEXEC_TYPE_CRASH) return 0; =20 image->kho.fdt =3D virt_to_phys(kho_out.fdt); --=20 2.47.3 Amazon Web Services Development Center Germany GmbH Tamara-Danz-Str. 13 10243 Berlin Geschaeftsfuehrung: Christof Hellmis, Andreas Stieger Eingetragen am Amtsgericht Charlottenburg unter HRB 257764 B Sitz: Berlin Ust-ID: DE 365 538 597