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-rw-r--r--kernel/debug/kdb/kdb_private.h2
-rw-r--r--kernel/futex.c7
-rw-r--r--kernel/module.c21
-rw-r--r--kernel/tracepoint.c80
4 files changed, 87 insertions, 23 deletions
diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h
index 533e04e75a9c..f51b762d6886 100644
--- a/kernel/debug/kdb/kdb_private.h
+++ b/kernel/debug/kdb/kdb_private.h
@@ -234,7 +234,7 @@ extern struct task_struct *kdb_curr_task(int);
#define kdb_do_each_thread(g, p) do_each_thread(g, p)
#define kdb_while_each_thread(g, p) while_each_thread(g, p)
-#define GFP_KDB (in_interrupt() ? GFP_ATOMIC : GFP_KERNEL)
+#define GFP_KDB (in_dbg_master() ? GFP_ATOMIC : GFP_KERNEL)
extern void *debug_kmalloc(size_t size, gfp_t flags);
extern void debug_kfree(void *);
diff --git a/kernel/futex.c b/kernel/futex.c
index 199e63c5b612..70ad21bbb1d5 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2248,10 +2248,6 @@ static int __fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
oldowner = pi_state->owner;
- /* Owner died? */
- if (!pi_state->owner)
- newtid |= FUTEX_OWNER_DIED;
-
/*
* We are here because either:
*
@@ -2309,6 +2305,9 @@ retry:
}
newtid = task_pid_vnr(newowner) | FUTEX_WAITERS;
+ /* Owner died? */
+ if (!pi_state->owner)
+ newtid |= FUTEX_OWNER_DIED;
if (get_futex_value_locked(&uval, uaddr))
goto handle_fault;
diff --git a/kernel/module.c b/kernel/module.c
index e6afc950357a..d84f5e38456f 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2107,6 +2107,21 @@ static int verify_export_symbols(struct module *mod)
return 0;
}
+static bool ignore_undef_symbol(Elf_Half emachine, const char *name)
+{
+ /*
+ * On x86, PIC code and Clang non-PIC code may have call foo@PLT. GNU as
+ * before 2.37 produces an unreferenced _GLOBAL_OFFSET_TABLE_ on x86-64.
+ * i386 has a similar problem but may not deserve a fix.
+ *
+ * If we ever have to ignore many symbols, consider refactoring the code to
+ * only warn if referenced by a relocation.
+ */
+ if (emachine == EM_386 || emachine == EM_X86_64)
+ return !strcmp(name, "_GLOBAL_OFFSET_TABLE_");
+ return false;
+}
+
/* Change all symbols so that st_value encodes the pointer directly. */
static int simplify_symbols(struct module *mod, const struct load_info *info)
{
@@ -2148,8 +2163,10 @@ static int simplify_symbols(struct module *mod, const struct load_info *info)
break;
}
- /* Ok if weak. */
- if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
+ /* Ok if weak or ignored. */
+ if (!ksym &&
+ (ELF_ST_BIND(sym[i].st_info) == STB_WEAK ||
+ ignore_undef_symbol(info->hdr->e_machine, name)))
break;
pr_warn("%s: Unknown symbol %s (err %li)\n",
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index eda85bbf1c2e..a1f9be703002 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -59,6 +59,12 @@ struct tp_probes {
struct tracepoint_func probes[0];
};
+/* Called in removal of a func but failed to allocate a new tp_funcs */
+static void tp_stub_func(void)
+{
+ return;
+}
+
static inline void *allocate_probes(int count)
{
struct tp_probes *p = kmalloc(count * sizeof(struct tracepoint_func)
@@ -97,6 +103,7 @@ func_add(struct tracepoint_func **funcs, struct tracepoint_func *tp_func,
{
struct tracepoint_func *old, *new;
int nr_probes = 0;
+ int stub_funcs = 0;
int pos = -1;
if (WARN_ON(!tp_func->func))
@@ -113,14 +120,34 @@ func_add(struct tracepoint_func **funcs, struct tracepoint_func *tp_func,
if (old[nr_probes].func == tp_func->func &&
old[nr_probes].data == tp_func->data)
return ERR_PTR(-EEXIST);
+ if (old[nr_probes].func == tp_stub_func)
+ stub_funcs++;
}
}
- /* + 2 : one for new probe, one for NULL func */
- new = allocate_probes(nr_probes + 2);
+ /* + 2 : one for new probe, one for NULL func - stub functions */
+ new = allocate_probes(nr_probes + 2 - stub_funcs);
if (new == NULL)
return ERR_PTR(-ENOMEM);
if (old) {
- if (pos < 0) {
+ if (stub_funcs) {
+ /* Need to copy one at a time to remove stubs */
+ int probes = 0;
+
+ pos = -1;
+ for (nr_probes = 0; old[nr_probes].func; nr_probes++) {
+ if (old[nr_probes].func == tp_stub_func)
+ continue;
+ if (pos < 0 && old[nr_probes].prio < prio)
+ pos = probes++;
+ new[probes++] = old[nr_probes];
+ }
+ nr_probes = probes;
+ if (pos < 0)
+ pos = probes;
+ else
+ nr_probes--; /* Account for insertion */
+
+ } else if (pos < 0) {
pos = nr_probes;
memcpy(new, old, nr_probes * sizeof(struct tracepoint_func));
} else {
@@ -154,8 +181,9 @@ static void *func_remove(struct tracepoint_func **funcs,
/* (N -> M), (N > 1, M >= 0) probes */
if (tp_func->func) {
for (nr_probes = 0; old[nr_probes].func; nr_probes++) {
- if (old[nr_probes].func == tp_func->func &&
- old[nr_probes].data == tp_func->data)
+ if ((old[nr_probes].func == tp_func->func &&
+ old[nr_probes].data == tp_func->data) ||
+ old[nr_probes].func == tp_stub_func)
nr_del++;
}
}
@@ -174,14 +202,32 @@ static void *func_remove(struct tracepoint_func **funcs,
/* N -> M, (N > 1, M > 0) */
/* + 1 for NULL */
new = allocate_probes(nr_probes - nr_del + 1);
- if (new == NULL)
- return ERR_PTR(-ENOMEM);
- for (i = 0; old[i].func; i++)
- if (old[i].func != tp_func->func
- || old[i].data != tp_func->data)
- new[j++] = old[i];
- new[nr_probes - nr_del].func = NULL;
- *funcs = new;
+ if (new) {
+ for (i = 0; old[i].func; i++)
+ if ((old[i].func != tp_func->func
+ || old[i].data != tp_func->data)
+ && old[i].func != tp_stub_func)
+ new[j++] = old[i];
+ new[nr_probes - nr_del].func = NULL;
+ *funcs = new;
+ } else {
+ /*
+ * Failed to allocate, replace the old function
+ * with calls to tp_stub_func.
+ */
+ for (i = 0; old[i].func; i++)
+ if (old[i].func == tp_func->func &&
+ old[i].data == tp_func->data) {
+ old[i].func = tp_stub_func;
+ /* Set the prio to the next event. */
+ if (old[i + 1].func)
+ old[i].prio =
+ old[i + 1].prio;
+ else
+ old[i].prio = -1;
+ }
+ *funcs = old;
+ }
}
debug_print_probes(*funcs);
return old;
@@ -234,10 +280,12 @@ static int tracepoint_remove_func(struct tracepoint *tp,
tp_funcs = rcu_dereference_protected(tp->funcs,
lockdep_is_held(&tracepoints_mutex));
old = func_remove(&tp_funcs, func);
- if (IS_ERR(old)) {
- WARN_ON_ONCE(PTR_ERR(old) != -ENOMEM);
+ if (WARN_ON_ONCE(IS_ERR(old)))
return PTR_ERR(old);
- }
+
+ if (tp_funcs == old)
+ /* Failed allocating new tp_funcs, replaced func with stub */
+ return 0;
if (!tp_funcs) {
/* Removed last function */
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-24 16:52:18 +0000