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powerpc/xmon: Don't print hashed pointers in xmon
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Since commit ad67b74 ("printk: hash addresses printed with %p")
pointers printed with %p are hashed, ie. you don't see the actual
pointer value but rather a cryptographic hash of its value.

In xmon we want to see the actual pointer values, because xmon is a
debugger, so replace %p with %px which prints the actual pointer
value.

We justify doing this in xmon because 1) xmon is a kernel crash
debugger, it's only accessible via the console 2) xmon doesn't print
to dmesg, so the pointers it prints are not able to be leaked that
way.

Signed-off-by: Michael Ellerman <[email protected]>
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mpe committed Dec 6, 2017
1 parent 371b804 commit d810418
Showing 1 changed file with 5 additions and 5 deletions.
10 changes: 5 additions & 5 deletions arch/powerpc/xmon/xmon.c
Original file line number Diff line number Diff line change
Expand Up @@ -1590,7 +1590,7 @@ static void print_bug_trap(struct pt_regs *regs)
printf("kernel BUG at %s:%u!\n",
bug->file, bug->line);
#else
printf("kernel BUG at %p!\n", (void *)bug->bug_addr);
printf("kernel BUG at %px!\n", (void *)bug->bug_addr);
#endif
#endif /* CONFIG_BUG */
}
Expand Down Expand Up @@ -2329,7 +2329,7 @@ static void dump_one_paca(int cpu)

p = &paca[cpu];

printf("paca for cpu 0x%x @ %p:\n", cpu, p);
printf("paca for cpu 0x%x @ %px:\n", cpu, p);

printf(" %-*s = %s\n", 20, "possible", cpu_possible(cpu) ? "yes" : "no");
printf(" %-*s = %s\n", 20, "present", cpu_present(cpu) ? "yes" : "no");
Expand Down Expand Up @@ -2945,7 +2945,7 @@ static void show_task(struct task_struct *tsk)
(tsk->exit_state & EXIT_DEAD) ? 'E' :
(tsk->state & TASK_INTERRUPTIBLE) ? 'S' : '?';

printf("%p %016lx %6d %6d %c %2d %s\n", tsk,
printf("%px %016lx %6d %6d %c %2d %s\n", tsk,
tsk->thread.ksp,
tsk->pid, tsk->parent->pid,
state, task_thread_info(tsk)->cpu,
Expand Down Expand Up @@ -2988,7 +2988,7 @@ static void show_pte(unsigned long addr)

if (setjmp(bus_error_jmp) != 0) {
catch_memory_errors = 0;
printf("*** Error dumping pte for task %p\n", tsk);
printf("*** Error dumping pte for task %px\n", tsk);
return;
}

Expand Down Expand Up @@ -3074,7 +3074,7 @@ static void show_tasks(void)

if (setjmp(bus_error_jmp) != 0) {
catch_memory_errors = 0;
printf("*** Error dumping task %p\n", tsk);
printf("*** Error dumping task %px\n", tsk);
return;
}

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