From: Lev Olshvang <levonshe@yandex.com>
To: "valdis.kletnieks@vt.edu" <valdis.kletnieks@vt.edu>
Cc: kernelnewbies <kernelnewbies@kernelnewbies.org>
Subject: Re: In a process context kernel_read returns -EINTR, how to proceed?
Date: Fri, 21 Dec 2018 16:51:29 +0300 [thread overview]
Message-ID: <764811545400289@myt2-dc4bba9bb23c.qloud-c.yandex.net> (raw)
In-Reply-To: <9348.1545324048@turing-police.cc.vt.edu>
Hi Valdis,
I need to read file inside LSM hook and I can not do it in user space
I forgot o mention that same error occurried both in 4.4 and 4.13 kernels
What alternative you can recommend to read file in kernel and avoid -EINTR?
Is vfs_read() different from kernel_read() ?
ThanX
Lev
20.12.2018, 23:09, "valdis.kletnieks@vt.edu" <valdis.kletnieks@vt.edu>:
> On Thu, 20 Dec 2018 13:33:09 +0300, Lev Olshvang said:
>> I use kernel_read to read file in chunks of 4K size in a process context
>> On several files, like libc, libm, I got -EINTR error.
>
> What are you trying to accomplish? This is not a recommended way to do things.
>
>> I do not understand who may interrupt such a small read, I suppose these
>> libraries are already mapped in other processes so no real I/O should be done.
>
> That should be a hint....
>
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next prev parent reply other threads:[~2018-12-21 13:51 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-12-20 10:33 In a process context kernel_read returns -EINTR, how to proceed? Lev Olshvang
2018-12-20 16:40 ` valdis.kletnieks
2018-12-21 13:51 ` Lev Olshvang [this message]
2018-12-21 14:00 ` Greg KH
2018-12-21 16:15 ` valdis.kletnieks
2018-12-23 8:41 ` Lev Olshvang
2018-12-23 8:53 ` valdis.kletnieks
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