Re: [RESEND PATCH 2/2] staging/olpc_docn: reorder the lock sequence to avoid potential dead lock
On Tue, Nov 05, 2013 at 06:01:00PM +0800, Gu Zheng wrote: The lock sequence of dcon_blank_fb(fb_info-lock --- console_lock) is against with the one of console_callback(console_lock --- fb_info-lock), it'll lead to a potential dead lock, so reorder the lock sequence of dcon_blank_fb to avoid the potential dead lock. Signed-off-by: Gu Zheng guz.f...@cn.fujitsu.com Relax, Greg isn't taking new patches for another three weeks because the merge window is open. Also what happened to [PATCH 1/2]? regards, dan carpenter ___ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
Re: [RESEND PATCH 2/2] staging/olpc_docn: reorder the lock sequence to avoid potential dead lock
Hi Dan, On 11/05/2013 07:02 PM, Dan Carpenter wrote: On Tue, Nov 05, 2013 at 06:01:00PM +0800, Gu Zheng wrote: The lock sequence of dcon_blank_fb(fb_info-lock --- console_lock) is against with the one of console_callback(console_lock --- fb_info-lock), it'll lead to a potential dead lock, so reorder the lock sequence of dcon_blank_fb to avoid the potential dead lock. Signed-off-by: Gu Zheng guz.f...@cn.fujitsu.com Relax, Greg isn't taking new patches for another three weeks because the merge window is open. Got it, I just want to gain some comments about this patch. Also what happened to [PATCH 1/2]? It fixes the similar issue of fb subsystem. https://patchwork.kernel.org/patch/3140121/ Regards, Gu regards, dan carpenter -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ ___ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
[PATCH 2/2] staging/olpc_docn: reorder the lock sequence to avoid potential dead lock
The lock sequence of dcon_blank_fb(fb_info-lock --- console_lock) is against
with the one of console_callback(console_lock --- fb_info-lock), it'll
lead to a potential dead lock, so reorder the lock sequence of dcon_blank_fb
to avoid the potential dead lock.
Signed-off-by: Gu Zheng guz.f...@cn.fujitsu.com
---
drivers/staging/olpc_dcon/olpc_dcon.c |6 --
1 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/olpc_dcon/olpc_dcon.c
b/drivers/staging/olpc_dcon/olpc_dcon.c
index 198595e..9db88d9 100644
--- a/drivers/staging/olpc_dcon/olpc_dcon.c
+++ b/drivers/staging/olpc_dcon/olpc_dcon.c
@@ -255,17 +255,19 @@ static bool dcon_blank_fb(struct dcon_priv *dcon, bool
blank)
{
int err;
+ console_lock();
if (!lock_fb_info(dcon-fbinfo)) {
+ console_unlock();
dev_err(dcon-client-dev, unable to lock framebuffer\n);
return false;
}
- console_lock();
+
dcon-ignore_fb_events = true;
err = fb_blank(dcon-fbinfo,
blank ? FB_BLANK_POWERDOWN : FB_BLANK_UNBLANK);
dcon-ignore_fb_events = false;
- console_unlock();
unlock_fb_info(dcon-fbinfo);
+ console_unlock();
if (err) {
dev_err(dcon-client-dev, couldn't %sblank framebuffer\n,
--
1.7.7
___
devel mailing list
de...@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
