From: Roman Penyaev <rpenyaev@suse.de>
To: Jens Axboe <axboe@kernel.dk>
Cc: linux-fsdevel@vger.kernel.org, linux-aio@kvack.org,
linux-block@vger.kernel.org, hch@lst.de, jmoyer@redhat.com,
avi@scylladb.com, linux-block-owner@vger.kernel.org
Subject: Re: [PATCH 05/17] Add io_uring IO interface
Date: Mon, 21 Jan 2019 10:13:32 +0100 [thread overview]
Message-ID: <20204806b30147da55990e639586cce1@suse.de> (raw)
In-Reply-To: <20190118161225.4545-6-axboe@kernel.dk>
On 2019-01-18 17:12, Jens Axboe wrote:
[...]
> +
> +static int io_uring_create(unsigned entries, struct io_uring_params
> *p,
> + bool compat)
> +{
> + struct user_struct *user = NULL;
> + struct io_ring_ctx *ctx;
> + int ret;
> +
> + if (entries > IORING_MAX_ENTRIES)
> + return -EINVAL;
> +
> + /*
> + * Use twice as many entries for the CQ ring. It's possible for the
> + * application to drive a higher depth than the size of the SQ ring,
> + * since the sqes are only used at submission time. This allows for
> + * some flexibility in overcommitting a bit.
> + */
> + p->sq_entries = roundup_pow_of_two(entries);
> + p->cq_entries = 2 * p->sq_entries;
> +
> + if (!capable(CAP_IPC_LOCK)) {
> + user = get_uid(current_user());
> + ret = __io_account_mem(user, ring_pages(p->sq_entries,
> + p->cq_entries));
> + if (ret) {
> + free_uid(user);
> + return ret;
> + }
> + }
> +
> + ctx = io_ring_ctx_alloc(p);
> + if (!ctx)
> + return -ENOMEM;
Hi Jens,
It seems pages should be "unaccounted" back here and uid freed if path
with "if (!capable(CAP_IPC_LOCK))" above was taken.
But really, could please someone explain me what is wrong with
allocating
all urings in mmap() without touching RLIMIT_MEMLOCK at all? Thus all
memory will be accounted to the caller app and if app is greedy it will
be killed by oom. What I'm missing?
--
Roman
next prev parent reply other threads:[~2019-01-21 9:13 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-18 16:12 [PATCHSET v6] io_uring IO interface Jens Axboe
2019-01-18 16:12 ` [PATCH 01/17] fs: add an iopoll method to struct file_operations Jens Axboe
2019-01-18 16:12 ` [PATCH 02/17] block: wire up block device iopoll method Jens Axboe
2019-01-18 16:12 ` [PATCH 03/17] block: add bio_set_polled() helper Jens Axboe
2019-01-18 16:12 ` [PATCH 04/17] iomap: wire up the iopoll method Jens Axboe
2019-01-18 16:12 ` [PATCH 05/17] Add io_uring IO interface Jens Axboe
2019-01-21 9:13 ` Roman Penyaev [this message]
2019-01-21 15:30 ` Jens Axboe
2019-01-21 15:58 ` Roman Penyaev
2019-01-21 16:23 ` Jens Axboe
2019-01-21 16:49 ` Roman Penyaev
2019-01-22 16:11 ` Jens Axboe
2019-01-18 16:12 ` [PATCH 06/17] io_uring: add fsync support Jens Axboe
2019-01-18 16:12 ` [PATCH 07/17] io_uring: support for IO polling Jens Axboe
2019-01-18 16:12 ` [PATCH 08/17] fs: add fget_many() and fput_many() Jens Axboe
2019-01-18 16:12 ` [PATCH 09/17] io_uring: use fget/fput_many() for file references Jens Axboe
2019-01-18 16:12 ` [PATCH 10/17] io_uring: batch io_kiocb allocation Jens Axboe
2019-01-18 16:12 ` [PATCH 11/17] block: implement bio helper to add iter bvec pages to bio Jens Axboe
2019-01-18 16:12 ` [PATCH 12/17] io_uring: add support for pre-mapped user IO buffers Jens Axboe
2019-01-18 16:12 ` [PATCH 13/17] io_uring: add file set registration Jens Axboe
2019-01-18 16:12 ` [PATCH 14/17] io_uring: add submission polling Jens Axboe
2019-01-18 16:12 ` [PATCH 15/17] io_uring: add io_kiocb ref count Jens Axboe
2019-01-18 16:12 ` [PATCH 16/17] io_uring: add support for IORING_OP_POLL Jens Axboe
2019-01-18 16:12 ` [PATCH 17/17] io_uring: add io_uring_event cache hit information Jens Axboe
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