Marcelo,
The attached is a fix originally by Andrew Morton and discovered by the
preempt-kernel patch. It is in Alan's tree but was never merged into
Linus's.
There is a race between con_close and con_flush_chars.
n_tty_receive_buf writes to the tty queue and then flushes it via
con_flush_chars. If the console closes in between these operations,
con_flush_char barfs.
Please, for all that is righteous, apply.
Robert Love
diff -urN linux-2.4.17-pre7/drivers/char/console.c linux/drivers/char/console.c
--- linux-2.4.17-pre6/drivers/char/console.c Thu Dec 6 14:08:14 2001
+++ linux/drivers/char/console.c Thu Dec 6 14:09:06 2001
@@ -2356,8 +2356,14 @@
return;
pm_access(pm_con);
+
+ /*
+ * If we raced with con_close(), `vt' may be null.
+ * Hence this bandaid. - akpm
+ */
acquire_console_sem();
- set_cursor(vt->vc_num);
+ if (vt)
+ set_cursor(vt->vc_num);
release_console_sem();
}
-
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This archive was generated by hypermail 2b29 : Sat Dec 15 2001 - 21:00:15 EST