From: Greg KH <greg@kroah.com>
To: "孙世龙 sunshilong" <sunshilong369@gmail.com>
Cc: Kernelnewbies@kernelnewbies.org
Subject: Re: Are there some potential problems that I should be aware of if I allocate the memory which doesn't have any relation to peripheral hardwares(i.e. DMA, PCI, serial port and etc) by vmalloc() instead of kmalloc()?
Date: Sat, 27 Jun 2020 07:05:46 +0200 [thread overview]
Message-ID: <20200627050546.GC226238@kroah.com> (raw)
In-Reply-To: <CAAvDm6aZc5js0NKJZPdcTjNkKgg+3QGXLPyYaVosjgdvJcZq5w@mail.gmail.com>
On Fri, Jun 26, 2020 at 11:36:05PM +0800, 孙世龙 sunshilong wrote:
> Thank you for your attention to this matter.
>
> >Why are you having so many issues in allocating memory?
> I often saw the page allocation failure recently. I must resolve this problem.
What code is causing that failure by asking for memory that you do not
have? Please fix that up, the core kernel should be fine.
> I have no choice other than disabling these options
> (i.e. CONFIG-MIGRATION and CONFIG-COMPACTION)
> since I am using a real-time OS.
As was already stated, the use of "real-time" has nothing to do with
those options, or memory allocation, or anything else here. Please do
not get confused about the determinisitic operation of
interrupts/scheduling vs. anything else.
> It's easier to encounter such a problem since the said options are disabled.
Then fix your broken driver that is asking for so much memory on a
system that does not have it. Do you have a pointer to your driver
anywhere so we can review it?
good luck!
greg k-h
_______________________________________________
Kernelnewbies mailing list
Kernelnewbies@kernelnewbies.org
https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
next prev parent reply other threads:[~2020-06-27 5:06 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-26 8:30 Are there some potential problems that I should be aware of if I allocate the memory which doesn't have any relation to peripheral hardwares(i.e. DMA, PCI, serial port and etc) by vmalloc() instead of kmalloc()? 孙世龙 sunshilong
2020-06-26 14:13 ` Greg KH
2020-06-26 15:36 ` 孙世龙 sunshilong
2020-06-26 17:22 ` Valdis Klētnieks
2020-06-27 5:16 ` 孙世龙 sunshilong
2020-06-27 5:23 ` Greg KH
2020-06-27 6:00 ` 孙世龙 sunshilong
2020-06-27 7:05 ` Greg KH
2020-06-27 5:05 ` Greg KH [this message]
-- strict thread matches above, loose matches on Subject: below --
2020-06-26 12:40 Are there some potential problems that I should be aware of if I allocate the memory which doesn't have any relation to peripheral hardwares(i.e. DMA,PCI,serial " 孙世龙 sunshilong
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=20200627050546.GC226238@kroah.com \
--to=greg@kroah.com \
--cc=Kernelnewbies@kernelnewbies.org \
--cc=sunshilong369@gmail.com \
/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.