From: Alexey Gladkov <gladkov.alexey@gmail.com>
To: Jens Axboe <axboe@kernel.dk>
Cc: Kees Cook <keescook@chromium.org>,
Kernel Hardening <kernel-hardening@lists.openwall.com>,
Linux Containers <containers@lists.linux-foundation.org>,
Jann Horn <jannh@google.com>, LKML <linux-kernel@vger.kernel.org>,
Oleg Nesterov <oleg@redhat.com>,
linux-mm@kvack.org, "Eric W . Biederman" <ebiederm@xmission.com>,
Andrew Morton <akpm@linux-foundation.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
io-uring@vger.kernel.org
Subject: Re: [PATCH v6 3/7] Reimplement RLIMIT_NPROC on top of ucounts
Date: Mon, 22 Feb 2021 11:11:41 +0100 [thread overview]
Message-ID: <20210222101141.uve6hnftsakf4u7n@example.org> (raw)
In-Reply-To: <72214339-57fc-e47f-bb57-d1b39c69e38e@kernel.dk>
On Sun, Feb 21, 2021 at 04:38:10PM -0700, Jens Axboe wrote:
> On 2/15/21 5:41 AM, Alexey Gladkov wrote:
> > diff --git a/fs/io-wq.c b/fs/io-wq.c
> > index a564f36e260c..5b6940c90c61 100644
> > --- a/fs/io-wq.c
> > +++ b/fs/io-wq.c
> > @@ -1090,10 +1091,7 @@ struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data)
> > wqe->node = alloc_node;
> > wqe->acct[IO_WQ_ACCT_BOUND].max_workers = bounded;
> > atomic_set(&wqe->acct[IO_WQ_ACCT_BOUND].nr_running, 0);
> > - if (wq->user) {
> > - wqe->acct[IO_WQ_ACCT_UNBOUND].max_workers =
> > - task_rlimit(current, RLIMIT_NPROC);
> > - }
> > + wqe->acct[IO_WQ_ACCT_UNBOUND].max_workers = task_rlimit(current, RLIMIT_NPROC);
>
> This doesn't look like an equivalent transformation. But that may be
> moot if we merge the io_uring-worker.v3 series, as then you would not
> have to touch io-wq at all.
In the current code the wq->user is always set to current_user():
io_uring_create [1]
`- io_sq_offload_create
`- io_init_wq_offload [2]
`-io_wq_create [3]
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/fs/io_uring.c#n9752
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/fs/io_uring.c#n8107
[3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/fs/io-wq.c#n1070
So, specifying max_workers always happens.
--
Rgrds, legion
_______________________________________________
Containers mailing list
Containers@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/containers
WARNING: multiple messages have this Message-ID (diff)
From: Alexey Gladkov <gladkov.alexey@gmail.com>
To: Jens Axboe <axboe@kernel.dk>
Cc: LKML <linux-kernel@vger.kernel.org>,
io-uring@vger.kernel.org,
Kernel Hardening <kernel-hardening@lists.openwall.com>,
Linux Containers <containers@lists.linux-foundation.org>,
linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
Christian Brauner <christian.brauner@ubuntu.com>,
"Eric W . Biederman" <ebiederm@xmission.com>,
Jann Horn <jannh@google.com>, Kees Cook <keescook@chromium.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
Oleg Nesterov <oleg@redhat.com>
Subject: Re: [PATCH v6 3/7] Reimplement RLIMIT_NPROC on top of ucounts
Date: Mon, 22 Feb 2021 11:11:41 +0100 [thread overview]
Message-ID: <20210222101141.uve6hnftsakf4u7n@example.org> (raw)
In-Reply-To: <72214339-57fc-e47f-bb57-d1b39c69e38e@kernel.dk>
On Sun, Feb 21, 2021 at 04:38:10PM -0700, Jens Axboe wrote:
> On 2/15/21 5:41 AM, Alexey Gladkov wrote:
> > diff --git a/fs/io-wq.c b/fs/io-wq.c
> > index a564f36e260c..5b6940c90c61 100644
> > --- a/fs/io-wq.c
> > +++ b/fs/io-wq.c
> > @@ -1090,10 +1091,7 @@ struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data)
> > wqe->node = alloc_node;
> > wqe->acct[IO_WQ_ACCT_BOUND].max_workers = bounded;
> > atomic_set(&wqe->acct[IO_WQ_ACCT_BOUND].nr_running, 0);
> > - if (wq->user) {
> > - wqe->acct[IO_WQ_ACCT_UNBOUND].max_workers =
> > - task_rlimit(current, RLIMIT_NPROC);
> > - }
> > + wqe->acct[IO_WQ_ACCT_UNBOUND].max_workers = task_rlimit(current, RLIMIT_NPROC);
>
> This doesn't look like an equivalent transformation. But that may be
> moot if we merge the io_uring-worker.v3 series, as then you would not
> have to touch io-wq at all.
In the current code the wq->user is always set to current_user():
io_uring_create [1]
`- io_sq_offload_create
`- io_init_wq_offload [2]
`-io_wq_create [3]
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/fs/io_uring.c#n9752
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/fs/io_uring.c#n8107
[3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/fs/io-wq.c#n1070
So, specifying max_workers always happens.
--
Rgrds, legion
next prev parent reply other threads:[~2021-02-22 10:11 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-15 12:41 [PATCH v6 0/7] Count rlimits in each user namespace Alexey Gladkov
2021-02-15 12:41 ` Alexey Gladkov
2021-02-15 12:41 ` [PATCH v6 1/7] Increase size of ucounts to atomic_long_t Alexey Gladkov
2021-02-15 12:41 ` Alexey Gladkov
2021-02-15 12:41 ` [PATCH v6 2/7] Add a reference to ucounts for each cred Alexey Gladkov
2021-02-15 12:41 ` Alexey Gladkov
2021-02-15 12:41 ` [PATCH v6 3/7] Reimplement RLIMIT_NPROC on top of ucounts Alexey Gladkov
2021-02-15 12:41 ` Alexey Gladkov
2021-02-21 23:38 ` Jens Axboe
2021-02-21 23:38 ` Jens Axboe
2021-02-22 10:11 ` Alexey Gladkov [this message]
2021-02-22 10:11 ` Alexey Gladkov
2021-02-22 14:09 ` Jens Axboe
2021-02-22 14:09 ` Jens Axboe
2021-02-15 12:41 ` [PATCH v6 4/7] Reimplement RLIMIT_MSGQUEUE " Alexey Gladkov
2021-02-15 12:41 ` Alexey Gladkov
2021-02-15 12:41 ` [PATCH v6 5/7] Reimplement RLIMIT_SIGPENDING " Alexey Gladkov
2021-02-15 12:41 ` Alexey Gladkov
2021-02-15 12:41 ` [PATCH v6 6/7] Reimplement RLIMIT_MEMLOCK " Alexey Gladkov
2021-02-15 12:41 ` Alexey Gladkov
2021-02-15 15:09 ` kernel test robot
2021-02-15 15:09 ` kernel test robot
2021-02-15 15:09 ` kernel test robot
2021-02-15 17:49 ` kernel test robot
2021-02-15 17:49 ` kernel test robot
2021-02-15 17:49 ` kernel test robot
2021-02-16 11:12 ` [PATCH v7 " Alexey Gladkov
2021-02-16 11:12 ` Alexey Gladkov
2021-02-17 16:07 ` f009495a8d: BUG:KASAN:use-after-free_in_user_shm_unlock kernel test robot
2021-02-17 16:07 ` kernel test robot
2021-02-17 16:07 ` kernel test robot
2021-02-15 12:41 ` [PATCH v6 7/7] kselftests: Add test to check for rlimit changes in different user namespaces Alexey Gladkov
2021-02-15 12:41 ` Alexey Gladkov
2021-02-21 22:20 ` [PATCH v6 0/7] Count rlimits in each user namespace Linus Torvalds
2021-02-21 22:20 ` Linus Torvalds
2021-02-21 22:20 ` Linus Torvalds
2021-02-22 10:27 ` Alexey Gladkov
2021-02-22 10:27 ` Alexey Gladkov
2021-02-23 5:30 ` Eric W. Biederman
2021-02-23 5:30 ` Eric W. Biederman
2021-02-23 5:30 ` Eric W. Biederman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210222101141.uve6hnftsakf4u7n@example.org \
--to=gladkov.alexey@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=axboe@kernel.dk \
--cc=containers@lists.linux-foundation.org \
--cc=ebiederm@xmission.com \
--cc=io-uring@vger.kernel.org \
--cc=jannh@google.com \
--cc=keescook@chromium.org \
--cc=kernel-hardening@lists.openwall.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=oleg@redhat.com \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.