All of lore.kernel.org
 help / color / mirror / Atom feed
From: Pavel Machek <pavel@ucw.cz>
To: "Huang, Ying" <ying.huang@intel.com>
Cc: nigel@nigel.suspend2.net,
	Kexec Mailing List <kexec@lists.infradead.org>,
	linux-kernel@vger.kernel.org, "Rafael J. Wysocki" <rjw@sisk.pl>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-pm@lists.linux-foundation.org
Subject: Re: [PATCH 2/3 -mm] kexec jump -v8 : add write support to oldmem device
Date: Fri, 21 Dec 2007 11:17:10 +0100	[thread overview]
Message-ID: <20071221101710.GB10573@elf.ucw.cz> (raw)
In-Reply-To: <1198222420.1965.21.camel@caritas-dev.intel.com>

Hi!

> This patch adds writing support for /dev/oldmem. This can be used to
> 
> - Communicate between original kernel and kexeced kernel through write
>   to some pages in original kernel.
> 
> - Restore the memory contents of hibernated system in kexec based
>   hibernation.
> 
> Signed-off-by: Huang Ying <ying.huang@intel.com>
> 
> --- a/arch/x86/kernel/crash_dump_32.c
> +++ b/arch/x86/kernel/crash_dump_32.c
> +ssize_t write_oldmem_page(unsigned long pfn, const char *buf,
> +			  size_t csize, unsigned long offset, int
> userbuf)

> --- a/drivers/char/mem.c
> +++ b/drivers/char/mem.c
> @@ -348,6 +348,37 @@ static ssize_t read_oldmem(struct file *
>  	}
>  	return read;
>  }
> +
> +/*
> + * Write memory corresponding to the old kernel.
> + */
> +static ssize_t write_oldmem(struct file *file, const char __user *buf,
> +			    size_t count, loff_t *ppos)
> +{
...
> +		rc = write_oldmem_page(pfn, buf, csize, offset, 1);

I believe this is going to break compilation on non-32bit
machines. Or is crashdump only supported on i386?
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

_______________________________________________
kexec mailing list
kexec@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/kexec

WARNING: multiple messages have this Message-ID (diff)
From: Pavel Machek <pavel@ucw.cz>
To: "Huang, Ying" <ying.huang@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
	nigel@nigel.suspend2.net, "Rafael J. Wysocki" <rjw@sisk.pl>,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-kernel@vger.kernel.org,
	linux-pm@lists.linux-foundation.org,
	Kexec Mailing List <kexec@lists.infradead.org>
Subject: Re: [PATCH 2/3 -mm] kexec jump -v8 : add write support to oldmem device
Date: Fri, 21 Dec 2007 11:17:10 +0100	[thread overview]
Message-ID: <20071221101710.GB10573@elf.ucw.cz> (raw)
In-Reply-To: <1198222420.1965.21.camel@caritas-dev.intel.com>

Hi!

> This patch adds writing support for /dev/oldmem. This can be used to
> 
> - Communicate between original kernel and kexeced kernel through write
>   to some pages in original kernel.
> 
> - Restore the memory contents of hibernated system in kexec based
>   hibernation.
> 
> Signed-off-by: Huang Ying <ying.huang@intel.com>
> 
> --- a/arch/x86/kernel/crash_dump_32.c
> +++ b/arch/x86/kernel/crash_dump_32.c
> +ssize_t write_oldmem_page(unsigned long pfn, const char *buf,
> +			  size_t csize, unsigned long offset, int
> userbuf)

> --- a/drivers/char/mem.c
> +++ b/drivers/char/mem.c
> @@ -348,6 +348,37 @@ static ssize_t read_oldmem(struct file *
>  	}
>  	return read;
>  }
> +
> +/*
> + * Write memory corresponding to the old kernel.
> + */
> +static ssize_t write_oldmem(struct file *file, const char __user *buf,
> +			    size_t count, loff_t *ppos)
> +{
...
> +		rc = write_oldmem_page(pfn, buf, csize, offset, 1);

I believe this is going to break compilation on non-32bit
machines. Or is crashdump only supported on i386?
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

  reply	other threads:[~2007-12-21 10:18 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-12-21  7:33 [PATCH 2/3 -mm] kexec jump -v8 : add write support to oldmem device Huang, Ying
2007-12-21  7:33 ` Huang, Ying
2007-12-21 10:17 ` Pavel Machek [this message]
2007-12-21 10:17   ` Pavel Machek
2007-12-21 10:58   ` Bernhard Walle
2007-12-21 10:58   ` Bernhard Walle
2007-12-21 10:58     ` Bernhard Walle
2007-12-21 12:50   ` huang ying
2007-12-21 12:50   ` huang ying
2007-12-21 12:50     ` huang ying
2007-12-21 10:17 ` Pavel Machek
  -- strict thread matches above, loose matches on Subject: below --
2007-12-21  7:33 Huang, Ying

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=20071221101710.GB10573@elf.ucw.cz \
    --to=pavel@ucw.cz \
    --cc=akpm@linux-foundation.org \
    --cc=ebiederm@xmission.com \
    --cc=kexec@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@lists.linux-foundation.org \
    --cc=nigel@nigel.suspend2.net \
    --cc=rjw@sisk.pl \
    --cc=ying.huang@intel.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.