netdev - Re: [PATCH rdma-next 01/10] RDMA: Add access flags to ib_alloc_mr() and ib_mr_pool

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 6 Apr 2021 16:15:52 +0200
From:   Christoph Hellwig <hch@....de>
To:     Jason Gunthorpe <jgg@...dia.com>
Cc:     Christoph Hellwig <hch@....de>, Leon Romanovsky <leon@...nel.org>,
        Bart Van Assche <bvanassche@....org>,
        Doug Ledford <dledford@...hat.com>,
        Avihai Horon <avihaih@...dia.com>,
        Adit Ranadive <aditr@...are.com>,
        Anna Schumaker <anna.schumaker@...app.com>,
        Ariel Elior <aelior@...vell.com>,
        Bernard Metzler <bmt@...ich.ibm.com>,
        Chuck Lever <chuck.lever@...cle.com>,
        "David S. Miller" <davem@...emloft.net>,
        Dennis Dalessandro <dennis.dalessandro@...nelisnetworks.com>,
        Devesh Sharma <devesh.sharma@...adcom.com>,
        Faisal Latif <faisal.latif@...el.com>,
        Jack Wang <jinpu.wang@...os.com>,
        Jakub Kicinski <kuba@...nel.org>,
        "J. Bruce Fields" <bfields@...ldses.org>,
        Jens Axboe <axboe@...com>,
        Karsten Graul <kgraul@...ux.ibm.com>,
        Keith Busch <kbusch@...nel.org>, Lijun Ou <oulijun@...wei.com>,
        linux-cifs@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-nfs@...r.kernel.org, linux-nvme@...ts.infradead.org,
        linux-rdma@...r.kernel.org, linux-s390@...r.kernel.org,
        Max Gurtovoy <maxg@...lanox.com>,
        Max Gurtovoy <mgurtovoy@...dia.com>,
        "Md. Haris Iqbal" <haris.iqbal@...os.com>,
        Michael Guralnik <michaelgur@...dia.com>,
        Michal Kalderon <mkalderon@...vell.com>,
        Mike Marciniszyn <mike.marciniszyn@...nelisnetworks.com>,
        Naresh Kumar PBS <nareshkumar.pbs@...adcom.com>,
        netdev@...r.kernel.org, Potnuri Bharat Teja <bharat@...lsio.com>,
        rds-devel@....oracle.com, Sagi Grimberg <sagi@...mberg.me>,
        samba-technical@...ts.samba.org,
        Santosh Shilimkar <santosh.shilimkar@...cle.com>,
        Selvin Xavier <selvin.xavier@...adcom.com>,
        Shiraz Saleem <shiraz.saleem@...el.com>,
        Somnath Kotur <somnath.kotur@...adcom.com>,
        Sriharsha Basavapatna <sriharsha.basavapatna@...adcom.com>,
        Steve French <sfrench@...ba.org>,
        Trond Myklebust <trond.myklebust@...merspace.com>,
        VMware PV-Drivers <pv-drivers@...are.com>,
        Weihang Li <liweihang@...wei.com>,
        Yishai Hadas <yishaih@...dia.com>,
        Zhu Yanjun <zyjzyj2000@...il.com>
Subject: Re: [PATCH rdma-next 01/10] RDMA: Add access flags to
 ib_alloc_mr() and ib_mr_pool_init()

On Tue, Apr 06, 2021 at 11:04:37AM -0300, Jason Gunthorpe wrote:
> It might be idiodic, but I have to keep the uverbs thing working
> too.
> 
> There is a lot of assumption baked in to all the drivers that
> user/kernel is the same thing, we'd have to go in and break this.
> 
> Essentially #2 ends up as deleting IB_ACCESS_RELAXED_ORDERING kernel
> side and instead doing some IB_ACCESS_DISABLE_RO in kernel,
> translating uverbs IBV_ACCESS_* to this then finding and inverting all
> the driver logic and also finding and unblocking all the places that
> enforce valid access flags in the drivers. It is complicated enough

Inverting the polarity of a flag at the uapi boundary is pretty
trivial and we already do it all over the kernel.

Do we actually ever need the strict ordering semantics in the kernel?