From 00c2cae6b66a913e8d9a39073988e4aa5baff0d8 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Fri, 16 Jun 2023 11:06:56 +0200 Subject: scsi: lpfc: Fix lpfc_name struct packing clang points out that the lpfc_name structure has an 8-byte alignment requirement on most architectures, but is embedded in a number of other structures that are forced to be only 1-byte aligned: drivers/scsi/lpfc/lpfc_hw.h:1516:30: error: field pe within 'struct lpfc_fdmi_reg_port_list' is less aligned than 'struct lpfc_fdmi_port_entry' and is usually due to 'struct lpfc_fdmi_reg_port_list' being packed, which can lead to unaligned accesses [-Werror,-Wunaligned-access] struct lpfc_fdmi_port_entry pe; drivers/scsi/lpfc/lpfc_hw.h:850:19: error: field portName within 'struct _ADISC' is less aligned than 'struct lpfc_name' and is usually due to 'struct _ADISC' being packed, which can lead to unaligned accesses [-Werror,-Wunaligned-access] drivers/scsi/lpfc/lpfc_hw.h:851:19: error: field nodeName within 'struct _ADISC' is less aligned than 'struct lpfc_name' and is usually due to 'struct _ADISC' being packed, which can lead to unaligned accesses [-Werror,-Wunaligned-access] drivers/scsi/lpfc/lpfc_hw.h:922:19: error: field portName within 'struct _RNID' is less aligned than 'struct lpfc_name' and is usually due to 'struct _RNID' being packed, which can lead to unaligned accesses [-Werror,-Wunaligned-access] drivers/scsi/lpfc/lpfc_hw.h:923:19: error: field nodeName within 'struct _RNID' is less aligned than 'struct lpfc_name' and is usually due to 'struct _RNID' being packed, which can lead to unaligned accesses [-Werror,-Wunaligned-access] From the git history, I can see that all the __packed annotations were done specifically to avoid introducing implicit padding around the lpfc_name instances, though this was probably the wrong approach. To improve this, only annotate the one uint64_t field inside of lpfc_name as packed, with an explicit 4-byte alignment, as is the default already on the 32-bit x86 ABI but not on most others. With this, the other __packed annotations can be removed again, as this avoids the incorrect padding. Two other structures change their layout as a result of this change: - struct _LOGO never gained a __packed annotation even though it has the same alignment problem as the others but is not used anywhere in the driver today. - struct serv_param similarly has this issue, and it is used, my guess is that this is only an internal structure rather than part of a binary interface, so the padding has no negative effect here. Signed-off-by: Arnd Bergmann Link: https://lore.kernel.org/r/20230616090705.2623408-1-arnd@kernel.org Reviewed-by: Justin Tee Signed-off-by: Martin K. Petersen --- drivers/scsi/lpfc/lpfc_hw.h | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'drivers/scsi') diff --git a/drivers/scsi/lpfc/lpfc_hw.h b/drivers/scsi/lpfc/lpfc_hw.h index 663755842e4a..aaea3e31944d 100644 --- a/drivers/scsi/lpfc/lpfc_hw.h +++ b/drivers/scsi/lpfc/lpfc_hw.h @@ -365,7 +365,7 @@ struct lpfc_name { uint8_t IEEE[6]; /* FC IEEE address */ } s; uint8_t wwn[8]; - uint64_t name; + uint64_t name __packed __aligned(4); } u; }; @@ -850,7 +850,7 @@ typedef struct _ADISC { /* Structure is in Big Endian format */ struct lpfc_name portName; struct lpfc_name nodeName; uint32_t DID; -} __packed ADISC; +} ADISC; typedef struct _FARP { /* Structure is in Big Endian format */ uint32_t Mflags:8; @@ -880,7 +880,7 @@ typedef struct _FAN { /* Structure is in Big Endian format */ uint32_t Fdid; struct lpfc_name FportName; struct lpfc_name FnodeName; -} __packed FAN; +} FAN; typedef struct _SCR { /* Structure is in Big Endian format */ uint8_t resvd1; @@ -924,7 +924,7 @@ typedef struct _RNID { /* Structure is in Big Endian format */ union { RNID_TOP_DISC topologyDisc; /* topology disc (0xdf) */ } un; -} __packed RNID; +} RNID; struct RLS { /* Structure is in Big Endian format */ uint32_t rls; @@ -1514,7 +1514,7 @@ struct lpfc_fdmi_hba_ident { struct lpfc_fdmi_reg_port_list { __be32 EntryCnt; struct lpfc_fdmi_port_entry pe; -} __packed; +}; /* * Register HBA(RHBA) -- cgit v1.2.3