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 9FC614EA367 for ; Thu, 9 Jul 2026 17:39:05 +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=1783618746; cv=none; b=FcFDcuUYpifcvGI9tTZJWjsvpc8jFlYXmZkEuZrIi55mQt/P0fx/HadgoVO1cuEWnKA9TNTnXnbm+rwscPqeyntBGMh+Is0rGGmAk4HXra2W5xT4zFWJgLUnnAVLAbFYDVmaJgaPOy6iN5fAo0FZYvDlH+LYM/IktKbdMnyyNVg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783618746; c=relaxed/simple; bh=dETmxWj74arIztuU4ZsUo0Nyxl81pttYd0U8+4gnE8o=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Re6q8hNzXmunA3B60pfBLZxsVdGg7aY18mrV7BVoXefafT8KAGBSLZyYi/9alK92GnE25dVRJR/Fmporgyq8rMfDLx/MXtz2GI0MFmFLnCMCVTh5wzzIbVKPP0MsSoYCJOOFOa5qcq5sadDwQIcy3l/QpW1brmOONBdebEO469U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IccSNhjY; 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="IccSNhjY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 55D501F00AC4; Thu, 9 Jul 2026 17:39:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783618745; bh=Mc07LIN06reXb1mRXRVR0d4cmBqcpz+nSq+c6qEbD74=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=IccSNhjYeJaqPSf8ag53sGrW6ORxiXj47H8CbBQoNXzqKwasA711GRVEy5o5lXvK6 IZek62dhMYpXoIAy4GQQEHSpmu3hHrC9BgXIxcD/+hquTUAS1cMK5wM0QvHqAJ9YS6 XwnwBbpn+uvulYUwB/M2Z4dogeA4NehcezY3B+/xgHbIxIxNGadJyIBVcHMY3pFQMZ Cjlt7sAJGLAyTqwLVcvYdH2kg2XEQU9PV7xBzsudHhO/bzkQErmpLztm00PA+I1hqH SZ3vF0SWv5S3XlHxCmhaf1rtKRYzyjObVdrWFdJyufjt3u3+AgTG6gnaffS/z7afSA nlZ5Nq0yx2sxQ== From: Pratyush Yadav To: Mike Rapoport , Pasha Tatashin , Pratyush Yadav , Alexander Graf , Muchun Song , Oscar Salvador , David Hildenbrand , Andrew Morton , Jason Miu , Jork Loeser Cc: kexec@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 13/21] kho: expose kho_scratch_overlap() to kexec_handover.h Date: Thu, 9 Jul 2026 19:38:02 +0200 Message-ID: <20260709173821.429921-14-pratyush@kernel.org> X-Mailer: git-send-email 2.55.0.141.g00534a21ce-goog In-Reply-To: <20260709173821.429921-1-pratyush@kernel.org> References: <20260709173821.429921-1-pratyush@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: "Pratyush Yadav (Google)" Support for discovering memory blocks with no preserved memory will be added in coming patches. These areas will also be marked as scratch to allow allocations from them. Memblock will switch to looking through the scratch array to decide the right migratetype. Expose kho_scratch_overlap() to KHO users. Since it is now used by non-debug code, move it out of kexec_handover_debug.c and into kexec_handover.c. Gate the overlap checks in kho_preserve_folio() and kho_preserve_pages() by IS_ENABLED(CONFIG_KEXEC_HANDOVER_DEBUG) instead. Since kexec_handover_debug.c is now empty, delete it. No functional changes. Signed-off-by: Pratyush Yadav (Google) --- include/linux/kexec_handover.h | 7 ++++++ kernel/liveupdate/Makefile | 1 - kernel/liveupdate/kexec_handover.c | 22 ++++++++++++++++-- kernel/liveupdate/kexec_handover_debug.c | 25 --------------------- kernel/liveupdate/kexec_handover_internal.h | 9 -------- 5 files changed, 27 insertions(+), 37 deletions(-) delete mode 100644 kernel/liveupdate/kexec_handover_debug.c diff --git a/include/linux/kexec_handover.h b/include/linux/kexec_handover.h index 48a9793c2b76..40cb95a80981 100644 --- a/include/linux/kexec_handover.h +++ b/include/linux/kexec_handover.h @@ -36,6 +36,8 @@ void kho_memory_init(void); void kho_populate(phys_addr_t fdt_phys, u64 fdt_len, phys_addr_t scratch_phys, u64 scratch_len); + +bool kho_scratch_overlap(phys_addr_t phys, size_t size); #else static inline bool kho_is_enabled(void) { @@ -112,6 +114,11 @@ static inline void kho_populate(phys_addr_t fdt_phys, u64 fdt_len, phys_addr_t scratch_phys, u64 scratch_len) { } + +static inline bool kho_scratch_overlap(phys_addr_t phys, size_t size) +{ + return false; +} #endif /* CONFIG_KEXEC_HANDOVER */ #endif /* LINUX_KEXEC_HANDOVER_H */ diff --git a/kernel/liveupdate/Makefile b/kernel/liveupdate/Makefile index eec9d3ae07eb..d9f469462556 100644 --- a/kernel/liveupdate/Makefile +++ b/kernel/liveupdate/Makefile @@ -8,7 +8,6 @@ luo-y := \ luo_session.o obj-$(CONFIG_KEXEC_HANDOVER) += kexec_handover.o -obj-$(CONFIG_KEXEC_HANDOVER_DEBUG) += kexec_handover_debug.o obj-$(CONFIG_KEXEC_HANDOVER_DEBUGFS) += kexec_handover_debugfs.o obj-$(CONFIG_LIVEUPDATE) += luo.o diff --git a/kernel/liveupdate/kexec_handover.c b/kernel/liveupdate/kexec_handover.c index 04bfcbf9cc55..b3b97a6ff9c8 100644 --- a/kernel/liveupdate/kexec_handover.c +++ b/kernel/liveupdate/kexec_handover.c @@ -765,6 +765,22 @@ static phys_addr_t __init scratch_size_node(int nid) return round_up(size, CMA_MIN_ALIGNMENT_BYTES); } +bool kho_scratch_overlap(phys_addr_t phys, size_t size) +{ + phys_addr_t scratch_start, scratch_end; + unsigned int i; + + for (i = 0; i < kho_scratch_cnt; i++) { + scratch_start = kho_scratch[i].addr; + scratch_end = kho_scratch[i].addr + kho_scratch[i].size; + + if (phys < scratch_end && (phys + size) > scratch_start) + return true; + } + + return false; +} + /** * kho_reserve_scratch - Reserve a contiguous chunk of memory for kexec * @@ -962,7 +978,8 @@ int kho_preserve_folio(struct folio *folio) const unsigned long pfn = folio_pfn(folio); const unsigned int order = folio_order(folio); - if (WARN_ON(kho_scratch_overlap(pfn << PAGE_SHIFT, PAGE_SIZE << order))) + if (IS_ENABLED(CONFIG_KEXEC_HANDOVER_DEBUG) && + WARN_ON(kho_scratch_overlap(pfn << PAGE_SHIFT, PAGE_SIZE << order))) return -EINVAL; return kho_radix_add_key(tree, kho_encode_radix_key(PFN_PHYS(pfn), @@ -1039,7 +1056,8 @@ int kho_preserve_pages(struct page *page, unsigned long nr_pages) unsigned long failed_pfn = 0; int err = 0; - if (WARN_ON(kho_scratch_overlap(start_pfn << PAGE_SHIFT, + if (IS_ENABLED(CONFIG_KEXEC_HANDOVER_DEBUG) && + WARN_ON(kho_scratch_overlap(start_pfn << PAGE_SHIFT, nr_pages << PAGE_SHIFT))) { return -EINVAL; } diff --git a/kernel/liveupdate/kexec_handover_debug.c b/kernel/liveupdate/kexec_handover_debug.c deleted file mode 100644 index 6efb696f5426..000000000000 --- a/kernel/liveupdate/kexec_handover_debug.c +++ /dev/null @@ -1,25 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * kexec_handover_debug.c - kexec handover optional debug functionality - * Copyright (C) 2025 Google LLC, Pasha Tatashin - */ - -#define pr_fmt(fmt) "KHO: " fmt - -#include "kexec_handover_internal.h" - -bool kho_scratch_overlap(phys_addr_t phys, size_t size) -{ - phys_addr_t scratch_start, scratch_end; - unsigned int i; - - for (i = 0; i < kho_scratch_cnt; i++) { - scratch_start = kho_scratch[i].addr; - scratch_end = kho_scratch[i].addr + kho_scratch[i].size; - - if (phys < scratch_end && (phys + size) > scratch_start) - return true; - } - - return false; -} diff --git a/kernel/liveupdate/kexec_handover_internal.h b/kernel/liveupdate/kexec_handover_internal.h index 0399ff107775..805d2a76c388 100644 --- a/kernel/liveupdate/kexec_handover_internal.h +++ b/kernel/liveupdate/kexec_handover_internal.h @@ -41,13 +41,4 @@ static inline void kho_debugfs_blob_remove(struct kho_debugfs *dbg, void *blob) { } #endif /* CONFIG_KEXEC_HANDOVER_DEBUGFS */ -#ifdef CONFIG_KEXEC_HANDOVER_DEBUG -bool kho_scratch_overlap(phys_addr_t phys, size_t size); -#else -static inline bool kho_scratch_overlap(phys_addr_t phys, size_t size) -{ - return false; -} -#endif /* CONFIG_KEXEC_HANDOVER_DEBUG */ - #endif /* LINUX_KEXEC_HANDOVER_INTERNAL_H */ -- 2.55.0.141.g00534a21ce-goog