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charset="UTF-8" X-Rspamd-Queue-Id: 113E2180006 X-Stat-Signature: 7igqgdzr6imt4xa338kjdw1i5jzzix51 X-Rspamd-Server: rspam06 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=ham autolearn_force=no version=4.0.1 X-Rspam-User: X-HE-Tag: 1793036543-451912 X-HE-Meta: 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 J3tTE/ZC 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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/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. Any future unaligned field addition should come with reserved field to keep the structure aligned. Signed-off-by: Tarun Sahu --- include/linux/kho/abi/luo.h | 25 +++++++++++++++++++------ include/linux/kho/abi/memfd.h | 11 ++++++++--- 2 files changed, 27 insertions(+), 9 deletions(-) diff --git a/include/linux/kho/abi/luo.h b/include/linux/kho/abi/luo.h index 288076de6d4a..899943877e41 100644 --- a/include/linux/kho/abi/luo.h +++ b/include/linux/kho/abi/luo.h @@ -58,6 +58,7 @@ #define _LINUX_KHO_ABI_LUO_H #include +#include #include #include @@ -82,7 +83,9 @@ struct luo_ser { u64 liveupdate_num; u64 sessions_pa; u64 flbs_pa; -} __packed; +}; + +static_assert(sizeof(struct luo_ser) == 32); #define LIVEUPDATE_HNDL_COMPAT_LENGTH 48 @@ -98,7 +101,9 @@ struct luo_file_ser { char compatible[LIVEUPDATE_HNDL_COMPAT_LENGTH]; u64 data; u64 token; -} __packed; +}; + +static_assert(sizeof(struct luo_file_ser) == 64); /** * struct luo_file_set_ser - Represents the serialized metadata for file set @@ -113,7 +118,9 @@ struct luo_file_ser { struct luo_file_set_ser { u64 files; u64 count; -} __packed; +}; + +static_assert(sizeof(struct luo_file_set_ser) == 16); /** * struct luo_session_ser - Represents the serialized metadata for a LUO session. @@ -131,7 +138,9 @@ 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); /* The max size is set so it can be reliably used during in serialization */ #define LIVEUPDATE_FLB_COMPAT_LENGTH 48 @@ -152,7 +161,9 @@ struct luo_session_ser { struct luo_flb_header_ser { u64 pgcnt; u64 count; -} __packed; +}; + +static_assert(sizeof(struct luo_flb_header_ser) == 16); /** * struct luo_flb_ser - Represents the serialized state of a single FLB object. @@ -175,7 +186,9 @@ struct luo_flb_ser { char name[LIVEUPDATE_FLB_COMPAT_LENGTH]; u64 data; u64 count; -} __packed; +}; + +static_assert(sizeof(struct luo_flb_ser) == 64); /* 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..7115a8a77cfd 100644 --- a/include/linux/kho/abi/memfd.h +++ b/include/linux/kho/abi/memfd.h @@ -11,6 +11,7 @@ #ifndef _LINUX_KHO_ABI_MEMFD_H #define _LINUX_KHO_ABI_MEMFD_H +#include #include #include @@ -20,7 +21,7 @@ * 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 +55,9 @@ struct memfd_luo_folio_ser { u64 pfn:52; u64 flags:12; u64 index; -} __packed; +}; + +static_assert(sizeof(struct memfd_luo_folio_ser) == 16); /* * The set of seals this version supports preserving. If support for any new @@ -85,7 +88,9 @@ struct memfd_luo_ser { u32 flags; u64 nr_folios; struct kho_vmalloc folios; -} __packed; +}; + +static_assert(sizeof(struct memfd_luo_ser) == 48); /* The compatibility string for memfd file handler */ #define MEMFD_LUO_FH_COMPATIBLE "memfd-v2" -- 2.56.0.307.g5fe7bd680c-goog