diff options
Diffstat (limited to 'arch/arm64/kernel/ftrace.c')
| -rw-r--r-- | arch/arm64/kernel/ftrace.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c index c13b1fc..50986e3 100644 --- a/arch/arm64/kernel/ftrace.c +++ b/arch/arm64/kernel/ftrace.c @@ -76,7 +76,7 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) if (offset < -SZ_128M || offset >= SZ_128M) { #ifdef CONFIG_ARM64_MODULE_PLTS - unsigned long *trampoline; + struct plt_entry trampoline; struct module *mod; /* @@ -104,22 +104,24 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) * is added in the future, but for now, the pr_err() below * deals with a theoretical issue only. */ - trampoline = (unsigned long *)mod->arch.ftrace_trampoline; - if (trampoline[0] != addr) { - if (trampoline[0] != 0) { + trampoline = get_plt_entry(addr); + if (!plt_entries_equal(mod->arch.ftrace_trampoline, + &trampoline)) { + if (!plt_entries_equal(mod->arch.ftrace_trampoline, + &(struct plt_entry){})) { pr_err("ftrace: far branches to multiple entry points unsupported inside a single module\n"); return -EINVAL; } /* point the trampoline to our ftrace entry point */ module_disable_ro(mod); - trampoline[0] = addr; + *mod->arch.ftrace_trampoline = trampoline; module_enable_ro(mod, true); /* update trampoline before patching in the branch */ smp_wmb(); } - addr = (unsigned long)&trampoline[1]; + addr = (unsigned long)(void *)mod->arch.ftrace_trampoline; #else /* CONFIG_ARM64_MODULE_PLTS */ return -EINVAL; #endif /* CONFIG_ARM64_MODULE_PLTS */ |
