diff options
| author | Pedro Alves <pedro@palves.net> | 2023-12-01 13:31:00 +0000 |
|---|---|---|
| committer | Pedro Alves <pedro@palves.net> | 2023-12-20 21:18:55 +0000 |
| commit | 249d08128787e4e0a977079aa09516d73f196f77 (patch) | |
| tree | 45bc735bae678089f08110cbdbbf7cc7ace28440 | |
| parent | d0b591497952db37ed7a5545ced7aad64433f79a (diff) | |
| download | gdb-249d08128787e4e0a977079aa09516d73f196f77.zip gdb-249d08128787e4e0a977079aa09516d73f196f77.tar.gz gdb-249d08128787e4e0a977079aa09516d73f196f77.tar.bz2 | |
displaced_step_finish: Don't fetch the regcache of exited threads
displaced_step_finish can be called with event_status.kind ==
TARGET_WAITKIND_THREAD_EXITED, and in that case it is not possible to
get at the already-exited thread's registers.
This patch moves the get_thread_regcache calls to branches that
actually need it, where we know the thread is still alive.
It also adds an assertion to get_thread_regcache, to help catching
these broken cases sooner.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Change-Id: I63b5eacb3e02a538fc5087c270d8025adfda88c3
| -rw-r--r-- | gdb/infrun.c | 19 | ||||
| -rw-r--r-- | gdb/regcache.c | 2 |
2 files changed, 14 insertions, 7 deletions
diff --git a/gdb/infrun.c b/gdb/infrun.c index 6dc0a2b..76693a3 100644 --- a/gdb/infrun.c +++ b/gdb/infrun.c @@ -2021,8 +2021,6 @@ displaced_step_finish (thread_info *event_thread, const target_waitstatus &event_status) { /* Check whether the parent is displaced stepping. */ - struct regcache *regcache = get_thread_regcache (event_thread); - struct gdbarch *gdbarch = regcache->arch (); inferior *parent_inf = event_thread->inf; /* If this was a fork/vfork/clone, this event indicates that the @@ -2040,10 +2038,15 @@ displaced_step_finish (thread_info *event_thread, gdbarch_displaced_step_restore_all_in_ptid. This is not enforced during gdbarch validation to support architectures which support displaced stepping but not forks. */ - if (event_status.kind () == TARGET_WAITKIND_FORKED - && gdbarch_supports_displaced_stepping (gdbarch)) - gdbarch_displaced_step_restore_all_in_ptid - (gdbarch, parent_inf, event_status.child_ptid ()); + if (event_status.kind () == TARGET_WAITKIND_FORKED) + { + struct regcache *parent_regcache = get_thread_regcache (event_thread); + struct gdbarch *gdbarch = parent_regcache->arch (); + + if (gdbarch_supports_displaced_stepping (gdbarch)) + gdbarch_displaced_step_restore_all_in_ptid + (gdbarch, parent_inf, event_status.child_ptid ()); + } displaced_step_thread_state *displaced = &event_thread->displaced_step_state; @@ -2082,11 +2085,13 @@ displaced_step_finish (thread_info *event_thread, child hasn't been added to the inferior list yet at this point. */ + struct regcache *parent_regcache = get_thread_regcache (event_thread); + struct gdbarch *gdbarch = parent_regcache->arch (); struct regcache *child_regcache = get_thread_arch_regcache (parent_inf, event_status.child_ptid (), gdbarch); /* Read PC value of parent. */ - CORE_ADDR parent_pc = regcache_read_pc (regcache); + CORE_ADDR parent_pc = regcache_read_pc (parent_regcache); displaced_debug_printf ("write child pc from %s to %s", paddress (gdbarch, diff --git a/gdb/regcache.c b/gdb/regcache.c index 6140a05..1217fe7 100644 --- a/gdb/regcache.c +++ b/gdb/regcache.c @@ -430,6 +430,8 @@ get_thread_regcache (process_stratum_target *target, ptid_t ptid) struct regcache * get_thread_regcache (thread_info *thread) { + gdb_assert (thread->state != THREAD_EXITED); + return get_thread_regcache (thread->inf->process_target (), thread->ptid); } |