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Diffstat (limited to 'arch/x86/kernel/unwind_orc.c')
-rw-r--r--arch/x86/kernel/unwind_orc.c39
1 files changed, 27 insertions, 12 deletions
diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
index 977ee75e047c..f610fde2d5c4 100644
--- a/arch/x86/kernel/unwind_orc.c
+++ b/arch/x86/kernel/unwind_orc.c
@@ -2,6 +2,7 @@
#include <linux/objtool.h>
#include <linux/module.h>
#include <linux/sort.h>
+#include <linux/bpf.h>
#include <asm/ptrace.h>
#include <asm/stacktrace.h>
#include <asm/unwind.h>
@@ -172,6 +173,25 @@ static struct orc_entry *orc_ftrace_find(unsigned long ip)
}
#endif
+/* Fake frame pointer entry -- used as a fallback for generated code */
+static struct orc_entry orc_fp_entry = {
+ .type = ORC_TYPE_CALL,
+ .sp_reg = ORC_REG_BP,
+ .sp_offset = 16,
+ .bp_reg = ORC_REG_PREV_SP,
+ .bp_offset = -16,
+};
+
+static struct orc_entry *orc_bpf_find(unsigned long ip)
+{
+#ifdef CONFIG_BPF_JIT
+ if (bpf_has_frame_pointer(ip))
+ return &orc_fp_entry;
+#endif
+
+ return NULL;
+}
+
/*
* If we crash with IP==0, the last successfully executed instruction
* was probably an indirect function call with a NULL function pointer,
@@ -186,15 +206,6 @@ static struct orc_entry null_orc_entry = {
.type = ORC_TYPE_CALL
};
-/* Fake frame pointer entry -- used as a fallback for generated code */
-static struct orc_entry orc_fp_entry = {
- .type = ORC_TYPE_CALL,
- .sp_reg = ORC_REG_BP,
- .sp_offset = 16,
- .bp_reg = ORC_REG_PREV_SP,
- .bp_offset = -16,
-};
-
static struct orc_entry *orc_find(unsigned long ip)
{
static struct orc_entry *orc;
@@ -238,6 +249,11 @@ static struct orc_entry *orc_find(unsigned long ip)
if (orc)
return orc;
+ /* BPF lookup: */
+ orc = orc_bpf_find(ip);
+ if (orc)
+ return orc;
+
return orc_ftrace_find(ip);
}
@@ -495,9 +511,8 @@ bool unwind_next_frame(struct unwind_state *state)
if (!orc) {
/*
* As a fallback, try to assume this code uses a frame pointer.
- * This is useful for generated code, like BPF, which ORC
- * doesn't know about. This is just a guess, so the rest of
- * the unwind is no longer considered reliable.
+ * This is just a guess, so the rest of the unwind is no longer
+ * considered reliable.
*/
orc = &orc_fp_entry;
state->error = true;