diff options
Diffstat (limited to 'arch/x86/kernel/unwind_orc.c')
| -rw-r--r-- | arch/x86/kernel/unwind_orc.c | 39 |
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; |
