Aw: Re: [External] : nfsd: memory leak when client does many file operations

[Jan Schunk]

Inside the VM I was not able to reproduce the issue on v6.5.x so I keep concentrating on v6.6.x.

Current status:

$ git bisect start v6.6 v6.5
Bisecting: 7882 revisions left to test after this (roughly 13 steps)
[a1c19328a160c80251868dbd80066dce23d07995] Merge tag 'soc-arm-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

--
$ git bisect good
Bisecting: 3935 revisions left to test after this (roughly 12 steps)
[e4f1b8202fb59c56a3de7642d50326923670513f] Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

--
$ git bisect bad
Bisecting: 2014 revisions left to test after this (roughly 11 steps)
[e0152e7481c6c63764d6ea8ee41af5cf9dfac5e9] Merge tag 'riscv-for-linus-6.6-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

--
$ git bisect bad
Bisecting: 975 revisions left to test after this (roughly 10 steps)
[4a3b1007eeb26b2bb7ae4d734cc8577463325165] Merge tag 'pinctrl-v6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl

--
$ git bisect good
Bisecting: 476 revisions left to test after this (roughly 9 steps)
[4debf77169ee459c46ec70e13dc503bc25efd7d2] Merge tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd

--
$ git bisect good
Bisecting: 237 revisions left to test after this (roughly 8 steps)
[e7e9423db459423d3dcb367217553ad9ededadc9] Merge tag 'v6.6-vfs.super.fixes.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

> Gesendet: Montag, den 25.03.2024 um 21:36 Uhr
> Von: "Chuck Lever III" <chuck.lever@xxxxxxxxxx>
> An: "Jan Schunk" <scpcom@xxxxxx>
> Cc: "Jeff Layton" <jlayton@xxxxxxxxxx>, "Neil Brown" <neilb@xxxxxxx>, "Olga Kornievskaia" <kolga@xxxxxxxxxx>, "Dai Ngo" <dai.ngo@xxxxxxxxxx>, "Tom Talpey" <tom@xxxxxxxxxx>, "Linux NFS Mailing List" <linux-nfs@xxxxxxxxxxxxxxx>, "linux-kernel@xxxxxxxxxxxxxxx" <linux-kernel@xxxxxxxxxxxxxxx>
> Betreff: Re: [External] : nfsd: memory leak when client does many file operations
> 
> 
> 
> > On Mar 25, 2024, at 4:26 PM, Jan Schunk <scpcom@xxxxxx> wrote:
> > 
> > I am building my own kernels, but I never tried kmemleak, is this just a Kconfig option?
> 
>   Location:
>     -> Kernel hacking
>       -> Memory Debugging
> (1)     -> Kernel memory leak detector (DEBUG_KMEMLEAK [=n])
> 
> 
> > What do you mean with "bisect between v6.3 and v6.4"?
> 
> After you "git clone" the kernel source:
> 
> $ git bisect start v6.4 v6.3
> 
> Build the kernel and test. If the test fails:
> 
> $ cd <your kernel source tree>; git bisect bad
> 
> If the test succeeds:
> 
> $ cd <your kernel source tree>; git bisect good
> 
> Rebuild and try again until it lands on the first broken commit.
> 
> 
> > Everything including v6.4 is OK, the problem starts at v6.5.
> 
> I misremembered. Use "$ git bisect start v6.5 v6.4" then.
> 
> 
> > I also looked at some code already but there are huge changes to mm that happened in v6.5 and v6.6 so for me it is heavy to compare it with older versions to find one or more commits that may cause the issue.
> 
> Bisection is a mechanical test-based process. You don't need
> to look at code until you've reached the first bad commit.
> 
> --
> Chuck Lever
> 
>