Re: [PATCH] locking/lockdep: Add CONFIG_LOCKDEP_AGGRESSIVE

2017-12-12 Thread Byungchul Park
On 12/13/2017 2:00 AM, Linus Torvalds wrote: On Mon, Dec 11, 2017 at 9:20 PM, Byungchul Park wrote: The *problem* is false positives, since locks and waiters in kernel are not classified properly So the problem is that those false positives apparently end up being a big deal for the filesyst

Re: [PATCH] locking/lockdep: Add CONFIG_LOCKDEP_AGGRESSIVE

2017-12-12 Thread Byungchul Park
On 12/12/2017 10:03 PM, Theodore Ts'o wrote: On Tue, Dec 12, 2017 at 02:20:32PM +0900, Byungchul Park wrote: The *problem* is false positives, since locks and waiters in kernel are not classified properly, at the moment, which is just a fact that is not related to cross-release stuff at all. IO

Re: [PATCH] locking/lockdep: Add CONFIG_LOCKDEP_AGGRESSIVE

2017-12-12 Thread Linus Torvalds
On Mon, Dec 11, 2017 at 9:20 PM, Byungchul Park wrote: > > The *problem* is false positives, since locks and waiters in > kernel are not classified properly So the problem is that those false positives apparently end up being a big deal for the filesystem people. I personally don't think the cod

Re: [PATCH] locking/lockdep: Add CONFIG_LOCKDEP_AGGRESSIVE

2017-12-12 Thread Matthew Wilcox
On Tue, Dec 12, 2017 at 08:03:43AM -0500, Theodore Ts'o wrote: > On Tue, Dec 12, 2017 at 02:20:32PM +0900, Byungchul Park wrote: > > The *problem* is false positives, since locks and waiters in > > kernel are not classified properly, at the moment, which is just > > a fact that is not related to cr

Re: [PATCH] locking/lockdep: Add CONFIG_LOCKDEP_AGGRESSIVE

2017-12-12 Thread Theodore Ts'o
On Tue, Dec 12, 2017 at 02:20:32PM +0900, Byungchul Park wrote: > > The *problem* is false positives, since locks and waiters in > kernel are not classified properly, at the moment, which is just > a fact that is not related to cross-release stuff at all. IOW, > that would be useful once all locks

Re: [PATCH] locking/lockdep: Add CONFIG_LOCKDEP_AGGRESSIVE

2017-12-11 Thread Byungchul Park
On 12/12/2017 6:06 AM, Linus Torvalds wrote: On Sun, Dec 10, 2017 at 7:50 PM, Theodore Ts'o wrote: CONFIG_LOCKDEP_CROSSRELEASE and CONFIG_LOCKDEP_COMPLETIONS can result in a large number of false positives because lockdep doesn't understand how to deal with multiple stacked loop or MD devices.

Re: [PATCH] locking/lockdep: Add CONFIG_LOCKDEP_AGGRESSIVE

2017-12-11 Thread Theodore Ts'o
On Mon, Dec 11, 2017 at 01:06:55PM -0800, Linus Torvalds wrote: > On Sun, Dec 10, 2017 at 7:50 PM, Theodore Ts'o wrote: > > CONFIG_LOCKDEP_CROSSRELEASE and CONFIG_LOCKDEP_COMPLETIONS can result > > in a large number of false positives because lockdep doesn't > > understand how to deal with multipl

Re: [PATCH] locking/lockdep: Add CONFIG_LOCKDEP_AGGRESSIVE

2017-12-11 Thread Linus Torvalds
On Sun, Dec 10, 2017 at 7:50 PM, Theodore Ts'o wrote: > CONFIG_LOCKDEP_CROSSRELEASE and CONFIG_LOCKDEP_COMPLETIONS can result > in a large number of false positives because lockdep doesn't > understand how to deal with multiple stacked loop or MD devices. Guys, can we just remove this nasty crud

Re: [PATCH] locking/lockdep: Add CONFIG_LOCKDEP_AGGRESSIVE

2017-12-10 Thread Theodore Ts'o
On Sun, Dec 10, 2017 at 10:50:17PM -0500, Theodore Ts'o wrote: > CONFIG_LOCKDEP_CROSSRELEASE and CONFIG_LOCKDEP_COMPLETIONS can result > in a large number of false positives because lockdep doesn't > understand how to deal with multiple stacked loop or MD devices. > > Until someone can figure out

[PATCH] locking/lockdep: Add CONFIG_LOCKDEP_AGGRESSIVE

2017-12-10 Thread Theodore Ts'o
CONFIG_LOCKDEP_CROSSRELEASE and CONFIG_LOCKDEP_COMPLETIONS can result in a large number of false positives because lockdep doesn't understand how to deal with multiple stacked loop or MD devices. Until someone can figure out how to automatically add annotations to all file system and storage devic