From 216203bdc2280d8fc5baf60707eee2051de1426e Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Tue, 13 Aug 2024 16:15:02 -0600 Subject: [PATCH 1/2] UAPI: net/sched: Use __struct_group() in flex struct tc_u32_sel Use the `__struct_group()` helper to create a new tagged `struct tc_u32_sel_hdr`. This structure groups together all the members of the flexible `struct tc_u32_sel` except the flexible array. As a result, the array is effectively separated from the rest of the members without modifying the memory layout of the flexible structure. This new tagged struct will be used to fix problematic declarations of middle-flex-arrays in composite structs[1]. [1] https://git.kernel.org/linus/d88cabfd9abc Signed-off-by: Gustavo A. R. Silva Link: https://patch.msgid.link/e59fe833564ddc5b2cc83056a4c504be887d6193.1723586870.git.gustavoars@kernel.org Signed-off-by: Jakub Kicinski --- include/uapi/linux/pkt_cls.h | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h index d36d9cdf0c00..2c32080416b5 100644 --- a/include/uapi/linux/pkt_cls.h +++ b/include/uapi/linux/pkt_cls.h @@ -246,16 +246,19 @@ struct tc_u32_key { }; struct tc_u32_sel { - unsigned char flags; - unsigned char offshift; - unsigned char nkeys; + /* New members MUST be added within the __struct_group() macro below. */ + __struct_group(tc_u32_sel_hdr, hdr, /* no attrs */, + unsigned char flags; + unsigned char offshift; + unsigned char nkeys; - __be16 offmask; - __u16 off; - short offoff; + __be16 offmask; + __u16 off; + short offoff; - short hoff; - __be32 hmask; + short hoff; + __be32 hmask; + ); struct tc_u32_key keys[]; }; From 6c5cdabb3ec325f1846dad72f520814bbda79dca Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Tue, 13 Aug 2024 16:15:31 -0600 Subject: [PATCH 2/2] cxgb4: Avoid -Wflex-array-member-not-at-end warning -Wflex-array-member-not-at-end was introduced in GCC-14, and we are getting ready to enable it, globally. Change the type of the middle struct member currently causing trouble from `struct tc_u32_sel` to `struct tc_u32_sel_hdr`. Fix the following warning: drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h:245:27: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] Signed-off-by: Gustavo A. R. Silva Link: https://patch.msgid.link/97388e8a7990975aa56cf0ada211764c735c3432.1723586870.git.gustavoars@kernel.org Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h index 9050568a034c..64663112cad8 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h +++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h @@ -242,7 +242,7 @@ struct cxgb4_next_header { * field's value to jump to next header such as IHL field * in IPv4 header. */ - struct tc_u32_sel sel; + struct tc_u32_sel_hdr sel; struct tc_u32_key key; /* location of jump to make */ const struct cxgb4_match_field *jump;