From: Pratyush Anand <pan...@redhat.com>

Entry symbols are not kprobe safe. So blacklist them for kprobing.

Signed-off-by: Pratyush Anand <pan...@redhat.com>
Signed-off-by: David A. Long <dave.l...@linaro.org>
Acked-by: Masami Hiramatsu <mhira...@kernel.org>
---
 arch/arm64/kernel/entry.S           |  3 +++
 arch/arm64/kernel/kprobes/kprobes.c | 26 ++++++++++++++++++++++++++
 arch/arm64/kernel/vmlinux.lds.S     |  1 +
 3 files changed, 30 insertions(+)

diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 12e8d2b..7d99bed 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -243,6 +243,7 @@ tsk .req    x28             // current thread_info
  * Exception vectors.
  */
 
+       .pushsection ".entry.text", "ax"
        .align  11
 ENTRY(vectors)
        ventry  el1_sync_invalid                // Synchronous EL1t
@@ -781,3 +782,5 @@ ENTRY(sys_rt_sigreturn_wrapper)
        mov     x0, sp
        b       sys_rt_sigreturn
 ENDPROC(sys_rt_sigreturn_wrapper)
+
+       .popsection
diff --git a/arch/arm64/kernel/kprobes/kprobes.c 
b/arch/arm64/kernel/kprobes/kprobes.c
index 189b0d2..ca0c0c9 100644
--- a/arch/arm64/kernel/kprobes/kprobes.c
+++ b/arch/arm64/kernel/kprobes/kprobes.c
@@ -30,6 +30,7 @@
 #include <asm/insn.h>
 #include <asm/uaccess.h>
 #include <asm/irq.h>
+#include <asm-generic/sections.h>
 
 #include "decode-insn.h"
 
@@ -519,6 +520,31 @@ int __kprobes longjmp_break_handler(struct kprobe *p, 
struct pt_regs *regs)
        return 1;
 }
 
+bool arch_within_kprobe_blacklist(unsigned long addr)
+{
+       extern char __idmap_text_start[], __idmap_text_end[];
+       extern char __hyp_idmap_text_start[], __hyp_idmap_text_end[];
+
+       if ((addr >= (unsigned long)__kprobes_text_start &&
+           addr < (unsigned long)__kprobes_text_end) ||
+           (addr >= (unsigned long)__entry_text_start &&
+           addr < (unsigned long)__entry_text_end) ||
+           (addr >= (unsigned long)__idmap_text_start &&
+           addr < (unsigned long)__idmap_text_end) ||
+           !!search_exception_tables(addr))
+               return true;
+
+       if (!is_kernel_in_hyp_mode()) {
+               if ((addr >= (unsigned long)__hyp_text_start &&
+                   addr < (unsigned long)__hyp_text_end) ||
+                   (addr >= (unsigned long)__hyp_idmap_text_start &&
+                   addr < (unsigned long)__hyp_idmap_text_end))
+                       return true;
+       }
+
+       return false;
+}
+
 int __init arch_init_kprobes(void)
 {
        return 0;
diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index 075ce32..9f59394 100644
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -118,6 +118,7 @@ SECTIONS
                        __exception_text_end = .;
                        IRQENTRY_TEXT
                        SOFTIRQENTRY_TEXT
+                       ENTRY_TEXT
                        TEXT_TEXT
                        SCHED_TEXT
                        LOCK_TEXT
-- 
2.5.0

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