From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A856435BDC3 for ; Fri, 14 Nov 2025 21:35:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763156127; cv=none; b=SkrC1eHlbonJc4OF5oWuhMJWA1JrG5lnByGqyZ2i5lvbDr+90rVm2GKJuaracgCPzxj1l4/ACEttGdF1DhGtSxGYsuW+v15Ij7Nr+OPtTTTRFmYm9SZjHTfcdN+a/7Moj2X0YrYI4b1CAF88K6E1qJfPOA9n+skkioEsQxNhgJU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763156127; c=relaxed/simple; bh=hO4vl0pTADgAddeQFb60oPdrL8IX+Je9XNTvEDMOOWw=; h=Date:To:From:Subject:Message-Id; b=pwcynhqO+30UZopXXNSIomU8YllzpM8lkUMw/y4DaWAJTP62Z6dsJM6wJoi5lwk5GA2v4mpGbmwJMWhJl8EVk9/Ww92qvGVClPvs+LWJKbvSmqyxpIc8tcmpJA4gzj/KWtXi5Dkoj+B3yiSyKpQVV2zU/yFCKJmcORP4idppOBE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=jUa9cj3D; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="jUa9cj3D" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 38858C4CEF1; Fri, 14 Nov 2025 21:35:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1763156127; bh=hO4vl0pTADgAddeQFb60oPdrL8IX+Je9XNTvEDMOOWw=; h=Date:To:From:Subject:From; b=jUa9cj3Daw1gqNjPca3I44aaXvksFJevpTEND1bDEqtMTpMAc9Uzkc0qLONmo7x1r UNL6aloKcsG8DUPWJ2+reYS/GDxhlV5i6XDEuCYTj2zkv3jFBIB8ui8Arx9YppU3Qx y/X2YJWV0bRYsfnRZqVAfIpJNandTBavRnCSXvdI= Date: Fri, 14 Nov 2025 13:35:26 -0800 To: mm-commits@vger.kernel.org,rppt@kernel.org,pratyush@kernel.org,kees@kernel.org,graf@amazon.com,ebiggers@google.com,dave@vasilevsky.ca,coxu@redhat.com,bhe@redhat.com,arnd@arndb.de,pasha.tatashin@soleen.com,akpm@linux-foundation.org From: Andrew Morton Subject: + kho-remove-global-preserved_mem_map-and-store-state-in-fdt.patch added to mm-nonmm-unstable branch Message-Id: <20251114213527.38858C4CEF1@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: kho: remove global preserved_mem_map and store state in FDT has been added to the -mm mm-nonmm-unstable branch. Its filename is kho-remove-global-preserved_mem_map-and-store-state-in-fdt.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kho-remove-global-preserved_mem_map-and-store-state-in-fdt.patch This patch will later appear in the mm-nonmm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Pasha Tatashin Subject: kho: remove global preserved_mem_map and store state in FDT Date: Fri, 14 Nov 2025 13:59:57 -0500 Currently, the serialized memory map is tracked via kho_out.preserved_mem_map and copied to the FDT during finalization. This double tracking is redundant. Remove preserved_mem_map from kho_out. Instead, maintain the physical address of the head chunk directly in the preserved-memory-map FDT property. Introduce kho_update_memory_map() to manage this property. This function handles: 1. Retrieving and freeing any existing serialized map (handling the abort/retry case). 2. Updating the FDT property with the new chunk address. This establishes the FDT as the single source of truth for the handover state. Link: https://lkml.kernel.org/r/20251114190002.3311679-9-pasha.tatashin@soleen.com Signed-off-by: Pasha Tatashin Reviewed-by: Mike Rapoport (Microsoft) Reviewed-by: Pratyush Yadav Cc: Alexander Graf Cc: Arnd Bergmann Cc: Baoquan He Cc: Coiby Xu Cc: Dave Vasilevsky Cc: Eric Biggers Cc: Kees Cook Signed-off-by: Andrew Morton --- kernel/liveupdate/kexec_handover.c | 43 ++++++++++++++++----------- 1 file changed, 26 insertions(+), 17 deletions(-) --- a/kernel/liveupdate/kexec_handover.c~kho-remove-global-preserved_mem_map-and-store-state-in-fdt +++ a/kernel/liveupdate/kexec_handover.c @@ -119,9 +119,6 @@ struct kho_out { struct mutex fdts_lock; struct kho_mem_track track; - /* First chunk of serialized preserved memory map */ - struct khoser_mem_chunk *preserved_mem_map; - struct kho_debugfs dbg; }; @@ -382,6 +379,27 @@ static void kho_mem_ser_free(struct khos } } +/* + * Update memory map property, if old one is found discard it via + * kho_mem_ser_free(). + */ +static void kho_update_memory_map(struct khoser_mem_chunk *first_chunk) +{ + void *ptr; + u64 phys; + + ptr = fdt_getprop_w(kho_out.fdt, 0, PROP_PRESERVED_MEMORY_MAP, NULL); + + /* Check and discard previous memory map */ + phys = get_unaligned((u64 *)ptr); + if (phys) + kho_mem_ser_free((struct khoser_mem_chunk *)phys_to_virt(phys)); + + /* Update with the new value */ + phys = first_chunk ? (u64)virt_to_phys(first_chunk) : 0; + put_unaligned(phys, (u64 *)ptr); +} + static int kho_mem_serialize(struct kho_out *kho_out) { struct khoser_mem_chunk *first_chunk = NULL; @@ -422,7 +440,7 @@ static int kho_mem_serialize(struct kho_ } } - kho_out->preserved_mem_map = first_chunk; + kho_update_memory_map(first_chunk); return 0; @@ -1223,8 +1241,7 @@ int kho_abort(void) if (!kho_out.finalized) return -ENOENT; - kho_mem_ser_free(kho_out.preserved_mem_map); - kho_out.preserved_mem_map = NULL; + kho_update_memory_map(NULL); kho_out.finalized = false; return 0; @@ -1234,21 +1251,15 @@ static int __kho_finalize(void) { void *root = kho_out.fdt; struct kho_sub_fdt *fdt; - u64 *preserved_mem_map; + u64 empty_mem_map = 0; int err; err = fdt_create(root, PAGE_SIZE); err |= fdt_finish_reservemap(root); err |= fdt_begin_node(root, ""); err |= fdt_property_string(root, "compatible", KHO_FDT_COMPATIBLE); - /** - * Reserve the preserved-memory-map property in the root FDT, so - * that all property definitions will precede subnodes created by - * KHO callers. - */ - err |= fdt_property_placeholder(root, PROP_PRESERVED_MEMORY_MAP, - sizeof(*preserved_mem_map), - (void **)&preserved_mem_map); + err |= fdt_property(root, PROP_PRESERVED_MEMORY_MAP, &empty_mem_map, + sizeof(empty_mem_map)); if (err) goto err_exit; @@ -1271,8 +1282,6 @@ static int __kho_finalize(void) if (err) goto err_exit; - *preserved_mem_map = (u64)virt_to_phys(kho_out.preserved_mem_map); - return 0; err_exit: _ Patches currently in -mm which might be from pasha.tatashin@soleen.com are lib-test_kho-check-if-kho-is-enabled.patch kho-make-debugfs-interface-optional.patch kho-add-interfaces-to-unpreserve-folios-page-ranges-and-vmalloc.patch memblock-unpreserve-memory-in-case-of-error.patch test_kho-unpreserve-memory-in-case-of-error.patch kho-dont-unpreserve-memory-during-abort.patch liveupdate-kho-move-to-kernel-liveupdate.patch liveupdate-kho-move-to-kernel-liveupdate-fix.patch maintainers-update-kho-maintainers.patch kho-fix-misleading-log-message-in-kho_populate.patch kho-convert-__kho_abort-to-return-void.patch kho-introduce-high-level-memory-allocation-api.patch kho-preserve-fdt-folio-only-once-during-initialization.patch kho-verify-deserialization-status-and-fix-fdt-alignment-access.patch kho-always-expose-output-fdt-in-debugfs.patch kho-simplify-serialization-and-remove-__kho_abort.patch kho-remove-global-preserved_mem_map-and-store-state-in-fdt.patch kho-remove-abort-functionality-and-support-state-refresh.patch kho-update-fdt-dynamically-for-subtree-addition-removal.patch kho-allow-kexec-load-before-kho-finalization.patch kho-allow-memory-preservation-state-updates-after-finalization.patch kho-add-kconfig-option-to-enable-kho-by-default.patch liveupdate-luo_core-luo_ioctl-live-update-orchestrator.patch liveupdate-luo_core-integrate-with-kho.patch reboot-call-liveupdate_reboot-before-kexec.patch liveupdate-luo_session-add-sessions-support.patch liveupdate-luo_ioctl-add-user-interface.patch liveupdate-luo_file-implement-file-systems-callbacks.patch liveupdate-luo_session-add-ioctls-for-file-preservation-and-state-management.patch liveupdate-luo_flb-introduce-file-lifecycle-bound-global-state.patch docs-add-luo-documentation.patch maintainers-add-liveupdate-entry.patch selftests-liveupdate-add-userspace-api-selftests.patch selftests-liveupdate-add-kexec-based-selftest-for-session-lifecycle.patch selftests-liveupdate-add-kexec-test-for-multiple-and-empty-sessions.patch tests-liveupdate-add-in-kernel-liveupdate-test.patch