diff options
Diffstat (limited to '0001-redhat-rh_kabi-introduce-RH_KABI_EXTEND_WITH_SIZE.patch')
| -rw-r--r-- | 0001-redhat-rh_kabi-introduce-RH_KABI_EXTEND_WITH_SIZE.patch | 101 |
1 files changed, 0 insertions, 101 deletions
diff --git a/0001-redhat-rh_kabi-introduce-RH_KABI_EXTEND_WITH_SIZE.patch b/0001-redhat-rh_kabi-introduce-RH_KABI_EXTEND_WITH_SIZE.patch deleted file mode 100644 index 518de15cd..000000000 --- a/0001-redhat-rh_kabi-introduce-RH_KABI_EXTEND_WITH_SIZE.patch +++ /dev/null @@ -1,101 +0,0 @@ -From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 -From: Jiri Benc <jbenc@redhat.com> -Date: Wed, 19 Feb 2020 11:52:19 +0100 -Subject: [PATCH] redhat: rh_kabi: introduce RH_KABI_EXTEND_WITH_SIZE -MIME-Version: 1.0 -Content-Type: text/plain; charset=UTF-8 -Content-Transfer-Encoding: 8bit - -RH-Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> -RH-Acked-by: Hangbin Liu <haliu@redhat.com> - -Upstream status: RHEL only - -This allows addition of a struct into struct while reserving extra space. -See the documentation in rh_kabi.h for details. - -The check for size is automatically disabled in -debug kernels that have -many fields larger than the production kernels (mutexes etc.) and that are -not under kABI guarantee. - -I'm also moving a misplaced comment for RH_KABI_FILL_HOLE. - -(Pointed out by Sabrina:) We need to force align the added field to 8 byte -offset. Otherwise, if the required alignment of the added field changed -later (e.g. it was a structure with only a single field that was changed -from int to char) and the previous field was smaller than long, it could -lead to the whole union shifting position and offsets of the following -fields could change. It's also safer to align the size, too. - -Let the 'size' parameter specify number of longs to be added and not number -of bytes. Note we assume a 64 bit architecture, which is the case for RHEL. - -Upstream Status: RHEL only -Signed-off-by: Jiri Benc <jbenc@redhat.com> ---- - include/linux/rh_kabi.h | 29 ++++++++++++++++++++++++++++- - 1 file changed, 28 insertions(+), 1 deletion(-) - -diff --git a/include/linux/rh_kabi.h b/include/linux/rh_kabi.h -index cdc636d3013d..4debb7aaad48 100644 ---- a/include/linux/rh_kabi.h -+++ b/include/linux/rh_kabi.h -@@ -45,11 +45,24 @@ - * RH_KABI_EXTEND - * Simple macro for adding a new element to a struct. - * -- * Warning: only use if a hole exists for _all_ arches. Use pahole to verify. -+ * RH_KABI_EXTEND_WITH_SIZE -+ * Adds a new element (usually a struct) to a struct and reserves extra -+ * space for the new element. The provided 'size' is the total space to -+ * be added in longs (i.e. it's 8 * 'size' bytes), including the size of -+ * the added element. It is automatically checked that the new element -+ * does not overflow the reserved space, now nor in the future. However, -+ * no attempt is done to check the content of the added element (struct) -+ * for kABI conformance - kABI checking inside the added element is -+ * effectively switched off. -+ * For any struct being added by RH_KABI_EXTEND_WITH_SIZE, it is -+ * recommended its content to be documented as not covered by kABI -+ * guarantee. - * - * RH_KABI_FILL_HOLE - * Simple macro for filling a hole in a struct. - * -+ * Warning: only use if a hole exists for _all_ arches. Use pahole to verify. -+ * - * RH_KABI_RENAME - * Simple macro for renaming an element without changing its type. This - * macro can be used in bitfields, for example. -@@ -133,8 +146,12 @@ - _Static_assert(__alignof__(struct{_new;}) <= __alignof__(struct{_orig;}), \ - __FILE__ ":" __stringify(__LINE__) ": " __stringify(_orig) " is not aligned the same as " __stringify(_new) RH_KABI_ALIGN_WARNING); \ - } -+# define __RH_KABI_CHECK_SIZE(_item, _size) \ -+ _Static_assert(sizeof(struct{_item;}) <= _size, \ -+ __FILE__ ":" __stringify(__LINE__) ": " __stringify(_item) " is larger than the reserved size (" __stringify(_size) " bytes)" RH_KABI_ALIGN_WARNING) - #else - # define __RH_KABI_CHECK_SIZE_ALIGN(_orig, _new) -+# define __RH_KABI_CHECK_SIZE(_item, _size) - #endif - - # define _RH_KABI_DEPRECATE(_type, _orig) _type rh_reserved_##_orig -@@ -186,6 +203,16 @@ - - #define RH_KABI_EXCLUDE(_elem) _RH_KABI_EXCLUDE(_elem); - -+/* -+ * Extending a struct while reserving extra space. -+ */ -+#define RH_KABI_EXTEND_WITH_SIZE(_new, _size) \ -+ RH_KABI_EXTEND(union { \ -+ _new; \ -+ unsigned long __UNIQUE_ID(rh_kabi_reserved)[_size]; \ -+ __RH_KABI_CHECK_SIZE(_new, 8 * (_size)); \ -+ }) -+ - /* - * RHEL macros to extend structs. - * --- -2.26.2 - |