On (09/25/18 14:23), Petr Mladek wrote:
> The 32GB was mentioned as an example one year ego. This is not enough
> for a new syscall from my point of view.
I agree. I didn't think of syslog(); was merely thinking about logbuf
and flushing it to the consoles. syslog() stuff is a bit complex. We
sort of don't expect user space to allocate 64G to read all log_buf
messages, do we.
I'm wondering if we can do something like this
---
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index cf275f4d7912..1b48b61da8fe 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -1110,9 +1110,15 @@ static void __init log_buf_len_update(unsigned size)
/* save requested log_buf_len since it's too early to process it */
static int __init log_buf_len_setup(char *str)
{
- unsigned size = memparse(str, &str);
+ u64 size = memparse(str, &str);
- log_buf_len_update(size);
+ if (size > UINT_MAX) {
+ size = UINT_MAX;
+ pr_err("log_buf over 4G is not supported. "
+ "Please contact printk maintainers.\n");
+ }
+
+ log_buf_len_update((unsigned int)size);
return 0;
}
---
So we could know that "the day has come".
-ss
