Hi, (add lkml)
On 12/06, Ben Hutchings wrote: > > On Wed, 2012-12-05 at 14:13 -0500, Joseph Salisbury wrote: > > > Hi Oleg, > > > > A bug was opened against the Ubuntu kernel[0]. It was found that > > reverting commit b40a79591ca918e7b91b0d9b6abd5d00f2e88c19 resolved this > > bug, and allowed suspend/resume to work properly. > > > > I see that you are the author of this patch, so I wanted to run it by > > you. I was thinking of requesting a revert for 3.2 stable, but I wanted > > to get your feedback first. > > > > Thanks, > > > > Joe > > > > > > [0] https://bugs.launchpad.net/ubuntu/+source/v86d/+bug/1080530 > > If I understand this rightly: > 1. Suspend is aborted because the v86d usermodehelper cannot be frozen. > 2. Before this fix, usermodehelpers could inherit PF_NOFREEZE (what > could possibly go wrong with that?!), which is why this didn't > previously happen. Yes, try_to_freeze_tasks() ignores PF_NOFREEZE tasks > 3. However, usermodehelpers are supposed to be disabled while the > freezer is running. Why is this one still running? __usermodehelper_disable() doesn't try to kill/stop/whatever the already spawned tasks... The question is, why v86d refuses to freeze? It sleeps in TASK_INTERRUPTIBLE. Oh... I seem to understand. This is 3.2 kernel, it also has PF_FREEZER_NOSIG. which should be cleared along with PF_NOFREEZE. This flag was removed upstream, but the older kernel need the fix. Could you test the patch below? Oleg. --- a/fs/exec.c +++ b/fs/exec.c @@ -1084,7 +1084,7 @@ int flush_old_exec(struct linux_binprm * set_fs(USER_DS); current->flags &= - ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD | PF_NOFREEZE); + ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD | PF_NOFREEZE | PF_FREEZER_NOSIG); flush_thread(); current->personality &= ~bprm->per_clear; -- 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/
