From: linux@arm.linux.org.uk (Russell King - ARM Linux)
To: linux-arm-kernel@lists.infradead.org
Subject: [RFC PATCH] kernel/kallsyms.c: only show legal kernel symbol
Date: Thu, 24 Oct 2013 09:45:59 +0100 [thread overview]
Message-ID: <20131024084559.GD16735@n2100.arm.linux.org.uk> (raw)
In-Reply-To: <87eh7bfoq9.fsf@rustcorp.com.au>
On Thu, Oct 24, 2013 at 11:51:18AM +1030, Rusty Russell wrote:
> Ming Lei <tom.leiming@gmail.com> writes:
> > Address of non-module kernel symbol should always be located
> > from CONFIG_PAGE_OFFSET on, so only show these legal kernel
> > symbols in /proc/kallsyms.
> >
> > On ARM, some symbols(see below) may drop in relocatable code, so
> > perf can't parse kernel symbols any more from /proc/kallsyms, this
> > patch fixes the problem.
> >
> > 00000000 t __vectors_start
> > 00000020 A cpu_v7_suspend_size
> > 00001000 t __stubs_start
> > 00001004 t vector_rst
> > 00001020 t vector_irq
> > 000010a0 t vector_dabt
> > 00001120 t vector_pabt
> > 000011a0 t vector_und
> > 00001220 t vector_addrexcptn
> > 00001224 t vector_fiq
> > 00001224 T vector_fiq_offset
> >
> > The issue can be fixed in scripts/kallsyms.c too, but looks this
> > approach is easier.
>
> This fix looks hacky; if these symbols are not available, don't just
> remove them from /proc/kallsyms, but don't put them in the kernel at
> all.
How do you "don't put them in the kernel at all" when they're used by
the kernel internally as offsets?
If you mean, just get rid of them, shall I just add these as magic
numbers instead based on the values in this email? Is that really a
sane solution?
No, we have to keep these symbols IMHO.
WARNING: multiple messages have this Message-ID (diff)
From: Russell King - ARM Linux <linux@arm.linux.org.uk>
To: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ming Lei <tom.leiming@gmail.com>,
Andrew Morton <akpm@linux-foundation.org>,
linux-kernel@vger.kernel.org, Chen Gang <gang.chen@asianux.com>,
linux-arm-kernel@lists.infradead.org
Subject: Re: [RFC PATCH] kernel/kallsyms.c: only show legal kernel symbol
Date: Thu, 24 Oct 2013 09:45:59 +0100 [thread overview]
Message-ID: <20131024084559.GD16735@n2100.arm.linux.org.uk> (raw)
In-Reply-To: <87eh7bfoq9.fsf@rustcorp.com.au>
On Thu, Oct 24, 2013 at 11:51:18AM +1030, Rusty Russell wrote:
> Ming Lei <tom.leiming@gmail.com> writes:
> > Address of non-module kernel symbol should always be located
> > from CONFIG_PAGE_OFFSET on, so only show these legal kernel
> > symbols in /proc/kallsyms.
> >
> > On ARM, some symbols(see below) may drop in relocatable code, so
> > perf can't parse kernel symbols any more from /proc/kallsyms, this
> > patch fixes the problem.
> >
> > 00000000 t __vectors_start
> > 00000020 A cpu_v7_suspend_size
> > 00001000 t __stubs_start
> > 00001004 t vector_rst
> > 00001020 t vector_irq
> > 000010a0 t vector_dabt
> > 00001120 t vector_pabt
> > 000011a0 t vector_und
> > 00001220 t vector_addrexcptn
> > 00001224 t vector_fiq
> > 00001224 T vector_fiq_offset
> >
> > The issue can be fixed in scripts/kallsyms.c too, but looks this
> > approach is easier.
>
> This fix looks hacky; if these symbols are not available, don't just
> remove them from /proc/kallsyms, but don't put them in the kernel at
> all.
How do you "don't put them in the kernel at all" when they're used by
the kernel internally as offsets?
If you mean, just get rid of them, shall I just add these as magic
numbers instead based on the values in this email? Is that really a
sane solution?
No, we have to keep these symbols IMHO.
next prev parent reply other threads:[~2013-10-24 8:45 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-23 3:18 [RFC PATCH] kernel/kallsyms.c: only show legal kernel symbol Ming Lei
2013-10-23 3:18 ` Ming Lei
2013-10-24 1:21 ` Rusty Russell
2013-10-24 1:21 ` Rusty Russell
2013-10-24 5:42 ` Ming Lei
2013-10-24 5:42 ` Ming Lei
2013-10-24 8:45 ` Russell King - ARM Linux [this message]
2013-10-24 8:45 ` Russell King - ARM Linux
2013-10-24 9:10 ` Ming Lei
2013-10-24 9:10 ` Ming Lei
2013-10-24 23:08 ` Rusty Russell
2013-10-24 23:08 ` Rusty Russell
2013-10-25 1:29 ` Ming Lei
2013-10-25 1:29 ` Ming Lei
2013-10-25 5:50 ` Rusty Russell
2013-10-25 5:50 ` Rusty Russell
2013-10-25 7:01 ` Ming Lei
2013-10-25 7:01 ` Ming Lei
2013-10-25 11:58 ` Rusty Russell
2013-10-25 11:58 ` Rusty Russell
2013-10-26 12:31 ` Ming Lei
2013-10-26 12:31 ` Ming Lei
2013-10-28 3:14 ` Rusty Russell
2013-10-28 3:14 ` Rusty Russell
2013-10-28 5:23 ` Ming Lei
2013-10-28 5:23 ` Ming Lei
2013-10-28 5:50 ` Rusty Russell
2013-10-28 5:50 ` Rusty Russell
2013-10-30 23:09 ` Russell King - ARM Linux
2013-10-30 23:09 ` Russell King - ARM Linux
2013-10-31 3:14 ` Rusty Russell
2013-10-31 3:14 ` Rusty Russell
2013-10-31 4:55 ` Ming Lei
2013-10-31 4:55 ` Ming Lei
2013-11-01 2:28 ` Rusty Russell
2013-11-01 2:28 ` Rusty Russell
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=20131024084559.GD16735@n2100.arm.linux.org.uk \
--to=linux@arm.linux.org.uk \
--cc=linux-arm-kernel@lists.infradead.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.