Possible tty VT1 disallocate regression

PATCH In review Ross Lagerwall 4 participants 7 messages Jun 14, 2013 – Jun 16, 2013 TTY layer and serial drivers

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Ross Lagerwall

author

2013-06-14 20:47 UTC #0 lore raw

Hi,

Ever since commit 421b40a6286e ("tty/vt: Fix vc_deallocate() lock order"), the first VT does not clear when I log out. AFAIK, this means that disallocation is not working? The problem only affects the first VT, the others clear when logging out.

Regards

Signature · 1 line

Ross Lagerwall

Greg KH

maintainer

2013-06-14 21:35 UTC #1 lore raw

Quoted 6 lines · Ross Lagerwall

Hi,
Ever since commit 421b40a6286e ("tty/vt: Fix vc_deallocate() lock order"), the first VT does not clear when I log out. AFAIK, this means that disallocation is not working? The problem only affects the first VT, the others clear when logging out.

And if you revert that patch, does it all start working again?

thanks,

greg k-h

p.s. In the future, please cc: the people who handled the patch you are asking about, otherwise stuff like this often gets missed in the noise of lkml.

Peter Hurley

2013-06-14 22:02 UTC #2 lore raw

Quoted 10 lines · Greg KH

Quoted 6 lines · Ross Lagerwall
Hi,
Ever since commit 421b40a6286e ("tty/vt: Fix vc_deallocate() lock order"), the first VT does not clear when I log out. AFAIK, this means that disallocation is not working? The problem only affects the first VT, the others clear when logging out.
And if you revert that patch, does it all start working again?

Quoted 7 lines

thanks,
greg k-h
p.s. In the future, please cc: the people who handled the patch you are asking about, otherwise stuff like this often gets missed in the noise of lkml.

I've already been re-reviewing the VT indexing to see if or what I missed.

Thanks,
Peter Hurley

Ross Lagerwall

author

2013-06-14 22:24 UTC #3 lore raw

PATCH 1/1 tty/vt: Return EBUSY if deallocating VT1 and it is busy

In reply to Greg KH

Commit 421b40a6286e ("tty/vt: Fix vc_deallocate() lock order") changed the behavior when deallocating VT 1. Previously if trying to deallocate VT1 and it is busy, we would return EBUSY. The commit changed this to return 0 (success).

This commit restores the old behavior.

Signed-off-by Ross Lagerwall <[email protected]>

---

Quoted 3 lines · Greg KH

p.s. In the future, please cc: the people who handled the patch you are asking about, otherwise stuff like this often gets missed in the noise of lkml.

Yes, sorry about that. I only remembered after I sent the email.

 drivers/tty/vt/vt_ioctl.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

drivers/tty/vt/vt_ioctl.c +1 -4

index fc2c06c..2bd78e2 100644
@@ -289,13 +289,10 @@ static int vt_disallocate(unsigned int vc_num)
 	struct vc_data *vc = NULL;
 	int ret = 0;
 
-	if (!vc_num)
-		return 0;
-
 	console_lock();
 	if (VT_BUSY(vc_num))
 		ret = -EBUSY;
-	else
+	else if (vc_num)
 		vc = vc_deallocate(vc_num);
 	console_unlock();

Signature · 1 line

1.8.3.1

Peter Hurley

Acked-by on v1 1/1

2013-06-14 23:02 UTC #4 lore raw

Re: [PATCH] tty/vt: Return EBUSY if deallocating VT1 and it is busy

Quoted 8 lines · Ross Lagerwall

Commit 421b40a6286e ("tty/vt: Fix vc_deallocate() lock order") changed the behavior when deallocating VT 1. Previously if trying to deallocate VT1 and it is busy, we would return EBUSY. The commit changed this to return 0 (success).
This commit restores the old behavior.
Signed-off-by Ross Lagerwall <[email protected]>

Thanks.

Acked-by Peter Hurley <[email protected]>

Greg KH

maintainer

2013-06-15 04:47 UTC #5 lore raw

Re: [PATCH] tty/vt: Return EBUSY if deallocating VT1 and it is busy

Quoted 6 lines · Peter Hurley

Quoted 5 lines · Ross Lagerwall
Commit 421b40a6286e ("tty/vt: Fix vc_deallocate() lock order") changed the behavior when deallocating VT 1. Previously if trying to deallocate VT1 and it is busy, we would return EBUSY. The commit changed this to return 0 (success).

Quoted 7 lines

Quoted 3 lines
This commit restores the old behavior.
Signed-off-by Ross Lagerwall <[email protected]>
Thanks.
Acked-by Peter Hurley <[email protected]>

Thanks for this, I'll queue it up for Linus soon.

greg k-h

Mikael Pettersson

Tested-by on v1 1/1

2013-06-16 17:35 UTC #6 lore raw

Re: [PATCH] tty/vt: Return EBUSY if deallocating VT1 and it is busy

In reply to Ross Lagerwall

Quoted 8 lines · Ross Lagerwall

Commit 421b40a6286e ("tty/vt: Fix vc_deallocate() lock order") changed the behavior when deallocating VT 1. Previously if trying to deallocate VT1 and it is busy, we would return EBUSY. The commit changed this to return 0 (success).
This commit restores the old behavior.
Signed-off-by Ross Lagerwall <[email protected]>

This solves the VT blanking regression I've seen with the 3.10-rc kernels.

Tested-by Mikael Pettersson <[email protected]>

Quoted 39 lines

---

Quoted 3 lines · Greg KH

p.s. In the future, please cc: the people who handled the patch you are asking about, otherwise stuff like this often gets missed in the noise of lkml.

Yes, sorry about that. I only remembered after I sent the email.

 drivers/tty/vt/vt_ioctl.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

drivers/tty/vt/vt_ioctl.c +1 -4

index fc2c06c..2bd78e2 100644
@@ -289,13 +289,10 @@ static int vt_disallocate(unsigned int vc_num)
 	struct vc_data *vc = NULL;
 	int ret = 0;
 
-	if (!vc_num)
-		return 0;
-
 	console_lock();
 	if (VT_BUSY(vc_num))
 		ret = -EBUSY;
-	else
+	else if (vc_num)
 		vc = vc_deallocate(vc_num);
 	console_unlock();

Signature · 7 lines

1.8.3.1

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