J. Bruce Fields <bfields@xxxxxxxxxxxx> wrote: > > > > No. I started bisecting, and it does appear to be a regression from the > > > > cred patches, but at some point in the middle there it hangs on boot (a > > > > softlockup report blames a spinlock in set_groups). > > > > > > Do you remember which patch you were at? > > More precisely: > - The last working commit is b6dff3ec... "CRED: Separate task > security context from task_struct". > - The first commit exhibiting the permissions problem is > a6f76f2... "CRED: Make execve() take advantage of > copy-on-write credentials". I presume by 'first' you mean 'latest'. > - The 9 commits in between (from f1752eec to d84f4f9) result in > a soft lookup on boot. I think the problem may be that f1752eec removes the lock initialisation for init_cred from the INIT_CRED() macro: - .lock = __SPIN_LOCK_UNLOCKED(p.lock), \ but doesn't add it to the out of line init_cred: +struct cred init_cred = { + .usage = ATOMIC_INIT(3), + .securebits = SECUREBITS_DEFAULT, + .cap_inheritable = CAP_INIT_INH_SET, + .cap_permitted = CAP_FULL_SET, + .cap_effective = CAP_INIT_EFF_SET, + .cap_bset = CAP_INIT_BSET, + .user = INIT_USER, + .group_info = &init_groups, +}; Can you try adding: .lock = __SPIN_LOCK_UNLOCKED(init_cred.lock), to that and also add: spin_lock_init(&pcred->lock); into copy_creds() see if the problem goes away? I'm a bit surprised that lockdep doesn't bark at this one - I thought it checked for lock initialisation. David -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html