Caught by UBSan:
../lib/eal/x86/include/rte_atomic_64.h:206:21: runtime error:
member access within misaligned address 0x7ffd9c67f228 for
type 'const rte_int128_t', which requires 16 byte alignment
0x7ffd9c67f228: note: pointer points here
00 00 00 00 c0 5d 3e 00 01 00 00 00 01 00 00 00 00 00 00 00
^
00 00 00 00 00 00 00 00 00 00 00 00
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior
../lib/eal/x86/include/rte_atomic_64.h:206:21 in
../lib/eal/x86/include/rte_atomic_64.h:206:21: runtime error:
member access within misaligned address 0x7ffd9c67f228 for type
'const union rte_int128_t::(anonymous at
../lib/eal/include/generic/rte_atomic.h:1102:2)', which requires
16 byte alignment
0x7ffd9c67f228: note: pointer points here
00 00 00 00 c0 5d 3e 00 01 00 00 00 01 00 00 00 00 00 00 00
^
00 00 00 00 00 00 00 00 00 00 00 00
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior
../lib/eal/x86/include/rte_atomic_64.h:206:21 in
../lib/eal/x86/include/rte_atomic_64.h:206:16: runtime error:
load of misaligned address 0x7ffd9c67f228 for type
'const uint64_t' (aka 'const unsigned long'), which requires
16 byte alignment
0x7ffd9c67f228: note: pointer points here
00 00 00 00 c0 5d 3e 00 01 00 00 00 01 00 00 00 00 00 00 00
^
00 00 00 00 00 00 00 00 00 00 00 00
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior
../lib/eal/x86/include/rte_atomic_64.h:206:21 in
Rather than explicitly set alignment in callers, mark the structure
itself with an alignment constraint.
Fixes: 3340202f5954 ("stack: add lock-free implementation")
Signed-off-by: David Marchand <david.march...@redhat.com>
Acked-by: Bruce Richardson <bruce.richard...@intel.com>
Acked-by: Konstantin Ananyev <konstantin.anan...@huawei.com>
---
Changes since v4:
- dropped ABI exception and updated RN,
Changes since v3:
- changed rte_stack_lf_head struct alignment,
---
doc/guides/rel_notes/release_25_11.rst | 3 +++
lib/stack/rte_stack.h | 4 ++--
2 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/doc/guides/rel_notes/release_25_11.rst
b/doc/guides/rel_notes/release_25_11.rst
index ccad6d89ff..aa9211dd60 100644
--- a/doc/guides/rel_notes/release_25_11.rst
+++ b/doc/guides/rel_notes/release_25_11.rst
@@ -100,6 +100,9 @@ ABI Changes
Also, make sure to start the actual text at the margin.
=======================================================
+* stack: The structure ``rte_stack_lf_head`` alignment has been updated to 16
bytes
+ to avoid unaligned accesses.
+
Known Issues
------------
diff --git a/lib/stack/rte_stack.h b/lib/stack/rte_stack.h
index 4439adfc42..fd17ac791d 100644
--- a/lib/stack/rte_stack.h
+++ b/lib/stack/rte_stack.h
@@ -33,14 +33,14 @@ struct rte_stack_lf_elem {
struct rte_stack_lf_elem *next; /**< Next pointer */
};
-struct rte_stack_lf_head {
+struct __rte_aligned(16) rte_stack_lf_head {
struct rte_stack_lf_elem *top; /**< Stack top */
uint64_t cnt; /**< Modification counter for avoiding ABA problem */
};
struct rte_stack_lf_list {
/** List head */
- alignas(16) struct rte_stack_lf_head head;
+ struct rte_stack_lf_head head;
/** List len */
RTE_ATOMIC(uint64_t) len;
};
--
2.50.0
