diff mbox series

xen/console: add comment about external console lock helper

Message ID 20240321110503.72916-1-roger.pau@citrix.com (mailing list archive)
State New
Headers show
Series xen/console: add comment about external console lock helper | expand

Commit Message

Roger Pau Monne March 21, 2024, 11:05 a.m. UTC 
The current console_lock_recursive_irqsave() implementation is not speculation
safe, however it's only used to prevent interleaved output.  Note this in the
function declaration in order for callers to be aware of the limitation.

No functional change.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
---
 xen/include/xen/console.h | 1 +
 1 file changed, 1 insertion(+)

Comments

Jan Beulich March 21, 2024, 12:10 p.m. UTC | #1 
On 21.03.2024 12:05, Roger Pau Monne wrote:
> The current console_lock_recursive_irqsave() implementation is not speculation
> safe, however it's only used to prevent interleaved output.  Note this in the
> function declaration in order for callers to be aware of the limitation.
> 
> No functional change.
> 
> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>

Acked-by: Jan Beulich <jbeulich@suse.com>
diff mbox series

Patch

diff --git a/xen/include/xen/console.h b/xen/include/xen/console.h
index 68759862e88d..6dfbade3ece3 100644
--- a/xen/include/xen/console.h
+++ b/xen/include/xen/console.h
@@ -20,6 +20,7 @@  void console_init_postirq(void);
 void console_endboot(void);
 int console_has(const char *device);
 
+/* Not speculation safe - only used to prevent interleaving of output. */
 unsigned long console_lock_recursive_irqsave(void);
 void console_unlock_recursive_irqrestore(unsigned long flags);
 void console_force_unlock(void);