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charset="UTF-8" X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: E39F640002 X-Stat-Signature: 8b7xaio7d43jcedmatx8yowm7zdrjsgy X-Rspam-User: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=4.0.1 X-HE-Tag: 1794286927-153695 X-HE-Meta: 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 S/QZ4eae 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 All structures in include/linux/kho/abi/block.h (struct kho_block_header_ser), include/linux/kho/abi/luo.h (struct luo_ser, struct luo_file_ser, struct luo_file_set_ser, struct luo_session_ser, struct luo_flb_header_ser, struct luo_flb_ser) and include/linux/kho/abi/memfd.h (struct memfd_luo_folio_ser, struct memfd_luo_ser) have naturally aligned fields on 64-bit architectures, with no padding holes between fields or tail padding. Assert both the structure size and 8-byte alignment under CONFIG_64BIT at compile time. Any future unaligned field addition should come with reserved field to keep the structure aligned. Signed-off-by: Tarun Sahu --- include/linux/kho/abi/block.h | 10 +++++++-- include/linux/kho/abi/luo.h | 38 +++++++++++++++++++++++++++++------ include/linux/kho/abi/memfd.h | 16 ++++++++++++--- 3 files changed, 53 insertions(+), 11 deletions(-) diff --git a/include/linux/kho/abi/block.h b/include/linux/kho/abi/block.h index d06d64b963be..36bdbaf9b3b8 100644 --- a/include/linux/kho/abi/block.h +++ b/include/linux/kho/abi/block.h @@ -12,7 +12,7 @@ * pre-update kernel to a post-update kernel. * * This interface is a contract. Any modification to the structure fields, - * compatible strings, or the layout of the `__packed` serialization + * compatible strings, or the layout of the serialization * structures defined here constitutes a breaking change. Such changes require * incrementing the version number in the `KHO_FDT_COMPATIBLE` string to * prevent a new kernel from misinterpreting data from an old kernel. @@ -26,6 +26,8 @@ #define _LINUX_KHO_ABI_BLOCK_H #include +#include +#include #include /** @@ -49,6 +51,10 @@ struct kho_block_header_ser { u64 next; u64 count; -} __packed; +}; + +static_assert(sizeof(struct kho_block_header_ser) == 16); +static_assert(!IS_ENABLED(CONFIG_64BIT) || + __alignof__(struct kho_block_header_ser) == 8); #endif /* _LINUX_KHO_ABI_BLOCK_H */ diff --git a/include/linux/kho/abi/luo.h b/include/linux/kho/abi/luo.h index 288076de6d4a..721949374fa1 100644 --- a/include/linux/kho/abi/luo.h +++ b/include/linux/kho/abi/luo.h @@ -58,6 +58,8 @@ #define _LINUX_KHO_ABI_LUO_H #include +#include +#include #include #include @@ -82,7 +84,11 @@ struct luo_ser { u64 liveupdate_num; u64 sessions_pa; u64 flbs_pa; -} __packed; +}; + +static_assert(sizeof(struct luo_ser) == 32); +static_assert(!IS_ENABLED(CONFIG_64BIT) || + __alignof__(struct luo_ser) == 8); #define LIVEUPDATE_HNDL_COMPAT_LENGTH 48 @@ -98,7 +104,11 @@ struct luo_file_ser { char compatible[LIVEUPDATE_HNDL_COMPAT_LENGTH]; u64 data; u64 token; -} __packed; +}; + +static_assert(sizeof(struct luo_file_ser) == 64); +static_assert(!IS_ENABLED(CONFIG_64BIT) || + __alignof__(struct luo_file_ser) == 8); /** * struct luo_file_set_ser - Represents the serialized metadata for file set @@ -113,7 +123,11 @@ struct luo_file_ser { struct luo_file_set_ser { u64 files; u64 count; -} __packed; +}; + +static_assert(sizeof(struct luo_file_set_ser) == 16); +static_assert(!IS_ENABLED(CONFIG_64BIT) || + __alignof__(struct luo_file_set_ser) == 8); /** * struct luo_session_ser - Represents the serialized metadata for a LUO session. @@ -131,7 +145,11 @@ struct luo_file_set_ser { struct luo_session_ser { char name[LIVEUPDATE_SESSION_NAME_LENGTH]; struct luo_file_set_ser file_set_ser; -} __packed; +}; + +static_assert(sizeof(struct luo_session_ser) == 80); +static_assert(!IS_ENABLED(CONFIG_64BIT) || + __alignof__(struct luo_session_ser) == 8); /* The max size is set so it can be reliably used during in serialization */ #define LIVEUPDATE_FLB_COMPAT_LENGTH 48 @@ -152,7 +170,11 @@ struct luo_session_ser { struct luo_flb_header_ser { u64 pgcnt; u64 count; -} __packed; +}; + +static_assert(sizeof(struct luo_flb_header_ser) == 16); +static_assert(!IS_ENABLED(CONFIG_64BIT) || + __alignof__(struct luo_flb_header_ser) == 8); /** * struct luo_flb_ser - Represents the serialized state of a single FLB object. @@ -175,7 +197,11 @@ struct luo_flb_ser { char name[LIVEUPDATE_FLB_COMPAT_LENGTH]; u64 data; u64 count; -} __packed; +}; + +static_assert(sizeof(struct luo_flb_ser) == 64); +static_assert(!IS_ENABLED(CONFIG_64BIT) || + __alignof__(struct luo_flb_ser) == 8); /* Kernel Live Update Test ABI */ #ifdef CONFIG_LIVEUPDATE_TEST diff --git a/include/linux/kho/abi/memfd.h b/include/linux/kho/abi/memfd.h index 08b10fea2afc..376a724a1d8c 100644 --- a/include/linux/kho/abi/memfd.h +++ b/include/linux/kho/abi/memfd.h @@ -11,6 +11,8 @@ #ifndef _LINUX_KHO_ABI_MEMFD_H #define _LINUX_KHO_ABI_MEMFD_H +#include +#include #include #include @@ -20,7 +22,7 @@ * memfd uses the ABI defined below for preserving its state across a kexec * reboot using the LUO. * - * The state is serialized into a packed structure `struct memfd_luo_ser` + * The state is serialized into `struct memfd_luo_ser` * which is handed over to the next kernel via the KHO mechanism. * * This interface is a contract. Any modification to the structure layout @@ -54,7 +56,11 @@ struct memfd_luo_folio_ser { u64 pfn:52; u64 flags:12; u64 index; -} __packed; +}; + +static_assert(sizeof(struct memfd_luo_folio_ser) == 16); +static_assert(!IS_ENABLED(CONFIG_64BIT) || + __alignof__(struct memfd_luo_folio_ser) == 8); /* * The set of seals this version supports preserving. If support for any new @@ -85,7 +91,11 @@ struct memfd_luo_ser { u32 flags; u64 nr_folios; struct kho_vmalloc folios; -} __packed; +}; + +static_assert(sizeof(struct memfd_luo_ser) == 48); +static_assert(!IS_ENABLED(CONFIG_64BIT) || + __alignof__(struct memfd_luo_ser) == 8); /* The compatibility string for memfd file handler */ #define MEMFD_LUO_FH_COMPATIBLE "memfd-v2" -- 2.56.0.506.g506a7eabc5-goog