Re: [PATCH v11 2/3] tty: hvc: pass DMA capable memory to put_chars()

[Jiri Slaby]

On 15. 10. 21, 4:46, Xianting Tian wrote:
@@ -151,9 +142,11 @@ static uint32_t vtermnos[MAX_NR_HVC_CONSOLES] =
  static void hvc_console_print(struct console *co, const char *b,
                              unsigned count)
  {
-       char c[N_OUTBUF] __ALIGNED__;
+       char *c;
        unsigned i = 0, n = 0;
        int r, donecr = 0, index = co->index;
+       unsigned long flags;
+       struct hvc_struct *hp;
  
  	/* Console access attempt outside of acceptable console range. */
        if (index >= MAX_NR_HVC_CONSOLES)
@@ -163,6 +156,13 @@ static void hvc_console_print(struct console *co, const 
char *b,
        if (vtermnos[index] == -1)
                return;
  
+	hp = cons_hvcs[index];
+       if (!hp)
+               return;

You effectively make the console unusable until someone calls 
hvc_alloc() for this device, correct? This doesn't look right. Neither 
you describe this change of behaviour in the commit log.

regards,
--
js
suse labs