This is an automated email from Gerrit. "Antonio Borneo <[email protected]>" just uploaded a new patch set to Gerrit, which you can find at https://review.openocd.org/c/openocd/+/9139
-- gerrit commit 48c26383e3e103987a266ec008d4387e85c2639b Author: Antonio Borneo <[email protected]> Date: Mon Sep 22 09:53:43 2025 +0200 target: cortex_m: add comment for breakpoint of length 3 Add a comment in the breakpoint code to clarify the check for the odd breakpoint length of 3 bytes, introduced by [1]. [1]: commit 0a5e03c12aff ("cortex_m.c: Use two byte breakpoint for 32bit Thumb-2 request"). Change-Id: I024863d10078b5d9062c876aa59ccf70a81bf641 Signed-off-by: Antonio Borneo <[email protected]> diff --git a/src/target/cortex_m.c b/src/target/cortex_m.c index 83fcd4c8f3..e8163c2163 100644 --- a/src/target/cortex_m.c +++ b/src/target/cortex_m.c @@ -2041,6 +2041,15 @@ int cortex_m_unset_breakpoint(struct target *target, struct breakpoint *breakpoi int cortex_m_add_breakpoint(struct target *target, struct breakpoint *breakpoint) { + /* + * GDB packets Z0 and z0 provide the 'kind' parameter that is target-specific + * and typically indicates the size in bytes of the breakpoint. + * But for 32-bit Thumb mode (Thumb-2) breakpoint, GDB provides 'kind = 3' to + * be used to derive the length information. See: + * https://sourceware.org/gdb/current/onlinedocs/gdb.html/ARM-Breakpoint-Kinds.html + * Since a four byte breakpoint could be unaligned, potentially requiring two + * memory accesses to set or remove it, always use two bytes breakpoint. + */ if (breakpoint->length == 3) { LOG_TARGET_DEBUG(target, "Using a two byte breakpoint for 32bit Thumb-2 request"); breakpoint->length = 2; --
