Re: [OT] Major Clock Drift

From: Alan Cox (
Date: Mon Feb 12 2001 - 04:48:47 EST

> > Why are interrupts being disabled for vesafb scrolling anyway ?
> Console writes happen under spin_lock_irq(console_lock).
> The only reason for this which I can see: the kernel
> can call printk() from interrupt context.

We certainly need to be able to call printk from interrupt context so that
bit is in itself reasonable, but not the cost.

Suppose vesafb did something like this, dropping the printk lock

        if(test_and_set_bit(0, &vesafb_lock))
                        // remember which bit of the dmesg ring to queue
        /* for the re-entry case this will block */
        do the usual stuff
                goto again;
        clear_bit(0, &vesafb_lock);

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
Please read the FAQ at

This archive was generated by hypermail 2b29 : Thu Feb 15 2001 - 21:00:18 EST