From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Berg Subject: Re: [BUG] NULL pointer de-ref when setting io.cost.qos on LUKS devices Date: Tue, 03 Mar 2020 15:40:38 +0100 Message-ID: <24bd31cdaa3ea945908bc11cea05d6aae6929240.camel@sipsolutions.net> References: <1dbdcbb0c8db70a08aac467311a80abcf7779575.camel@sipsolutions.net> <20200303141902.GB189690@mtj.thefacebook.com> (sfid-20200303_151905_302479_14795E89) Mime-Version: 1.0 Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-j4uCKWQWPoDS0sEousKX" Return-path: In-Reply-To: <20200303141902.GB189690-146+VewaZzwNjtGbbfXrCEEOCMrvLtNR@public.gmane.org> (sfid-20200303_151905_302479_14795E89) Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: To: Tejun Heo Cc: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org --=-j4uCKWQWPoDS0sEousKX Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Tue, 2020-03-03 at 09:19 -0500, Tejun Heo wrote: > Hello, >=20 > On Tue, Mar 03, 2020 at 03:13:10PM +0100, Benjamin Berg wrote: > > so, I tried to set io.latency for some cgroups for the root device, > > which is ext4 inside LVM inside LUKS. >=20 > It's pointless on compound devices. I think the right thing to do here > is disallowing to enable it on those devices. I believe systemd tries to resolve to /dev/sda but that seems to fail for me. So I think there is a bug in that code; I'll verify that and submit a fix if so. Which device should actually be selected? Is it /dev/sda or the mapper device that / is mounted from? Benjamin --=-j4uCKWQWPoDS0sEousKX Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEED2NO4vMS33W8E4AFq6ZWhpmFY3AFAl5ebGYACgkQq6ZWhpmF Y3DTFw//VcGWBCbgwz1EKl5qv3UCTAc1Ra0D+vtWN6PD21vXyMF+gU4yrxIF5ZO4 aW4FwhM0MgmrBRsgew/6pH1TkIsE8bIlh1h8fi921ISOVYygvu0QRKuQ6Gll1trA +yS+J9e9NrDAio1xPkopG/Lf/ZiyO9a88aeiGckEQ7j3xXEW4pCM42gttYoLugh3 qVI8vTvj1Ns0SCQ/qq25UH2Tk5h7IUA4efmNbeZElDGRBBAKhSGNg4r9zLZFVdU9 4PPQ69jBTXjK5uB2x6DuroH5vYHOlJcRb0yaZpFOMqbk5QoaXfi094gKBVllqdLB hAI0P3lR64xQhmSkP7J4Y8zkhDQMKiCFxbJDAk6a/HQmYSb3fc7tX7yBljZWI2HK Cthf7MGU3+ElqevQ8a/bglssB8Rw1ufoxOgh1TDDRSRVXmRm2szUY2V/EVQYqlT/ aqpogxLDCYKluvn6N6wAGLV1hPIeuUo6Ld34f0lcA69c/dccdBQ+CCM6ToAHvfMl +YQAN6cN2mV1iRKzjq3O3beVV1ueoOtaHDKbuHy22c7SqRx1mwZUuyydfuGpLNSv djo9Y9LPMBVL+hHkDNNtHFmV7vguTEqirD6nnoKj/HtUofyS9o/Ylh9EOhkr1eMi 9Q4cjZG2ydksugCidpVDL1ZbkeeFNH5OnJ4ZIWH0lvCy3y0dzHo= =NGp6 -----END PGP SIGNATURE----- --=-j4uCKWQWPoDS0sEousKX--