serial: cpm_uart: Avoid suspicious locking

Browse source

CHECK   drivers/tty/serial/cpm_uart/cpm_uart_core.c
drivers/tty/serial/cpm_uart/cpm_uart_core.c:1271:39: warning: context imbalance in 'cpm_uart_console_write' - unexpected unlock

Allthough 'nolock' is not expected to change, sparse find the following
form suspicious:

	if (unlikely(nolock)) {
		local_irq_save(flags);
	} else {
		spin_lock_irqsave(&pinfo->port.lock, flags);
	}

	cpm_uart_early_write(pinfo, s, count, true);

	if (unlikely(nolock)) {
		local_irq_restore(flags);
	} else {
		spin_unlock_irqrestore(&pinfo->port.lock, flags);
	}

Rewrite it a more obvious form:

	if (unlikely(oops_in_progress)) {
		local_irq_save(flags);
		cpm_uart_early_write(pinfo, s, count, true);
		local_irq_restore(flags);
	} else {
		spin_lock_irqsave(&pinfo->port.lock, flags);
		cpm_uart_early_write(pinfo, s, count, true);
		spin_unlock_irqrestore(&pinfo->port.lock, flags);
	}

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/f7da5cdc9287960185829cfef681a7d8614efa1f.1691068700.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

...

This commit is contained in:

Christophe Leroy 2023-08-03 15:56:42 +02:00 • committed by Greg Kroah-Hartman

parent 06b64930dc

commit 36ef11d311

1 changed files with 4 additions and 9 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

13

drivers/tty/serial/cpm_uart/cpm_uart_core.c

View file