linux-toradex.git/arch/x86/kernel/jump_label.c, branch v3.14.37

x86/jump_label: expect default_nop if static_key gets enabled on boot-up

2013-10-19T23:45:35+00:00

net_get_random_once(intrduced in the next patch) uses static_keys in
a way that they get enabled on boot-up instead of replaced with an
ideal_nop. So check for default_nop on initial enabling.

Other architectures don't check for this.

Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: "H. Peter Anvin" 
Cc: Steven Rostedt 
Cc: Jason Baron 
Cc: Peter Zijlstra 
Cc: Eric Dumazet 
Cc: "David S. Miller" 
Cc: x86@kernel.org
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller

Merge branch 'x86/jumplabel' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2013-09-11T02:43:23+00:00

Pull x86 jumplabel changes from Peter Anvin:
 "One more x86 tree for this merge window.  This tree improves the
  handling of jump labels, so that most of the time we don't have to do
  a massive initial patching run.

  Furthermore, we will error out of the jump label is not what is
  expected, eg if it has been corrupted or tampered with"

* 'x86/jumplabel' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/jump-label: Show where and what was wrong on errors
  x86/jump-label: Add safety checks to jump label conversions
  x86/jump-label: Do not bother updating nops if they are correct
  x86/jump-label: Use best default nops for inital jump label calls

x86/jump-label: Show where and what was wrong on errors

2013-08-07T01:54:33+00:00

When modifying text sections for jump labels, a paranoid check is
performed. If the check fails, the system "bugs". But why it failed
is not shown.

The BUG_ON()s in the jump label update code is replaced with bug_at(ip).
This is a function that will show what pointer failed, and what was
at the location of the failure that made jump label panic.

Signed-off-by: Steven Rostedt

x86/jump-label: Add safety checks to jump label conversions

2013-08-07T01:43:20+00:00

As with all modifying of kernel text, we need to be very paranoid.

When converting the jump label locations to and from nops to jumps
a check has been added to make sure what we are replacing is what we
expect, otherwise we bug.

Cc: H. Peter Anvin 
Cc: Jason Baron 
Signed-off-by: Steven Rostedt

x86/jump-label: Do not bother updating nops if they are correct

2013-08-07T01:43:18+00:00

On boot up, the jump label init function scans all the jump label locations
and converts them to the best nop for the machine. If the nop is already
the ideal nop, do not bother with changing it.

Cc: Jason Baron 
Cc: H. Peter Anvin 
Signed-off-by: Steven Rostedt

x86: Make jump_label use int3-based patching

2013-07-17T00:55:37+00:00

Make jump labels use text_poke_bp() for text patching instead of
text_poke_smp(), avoiding the need for stop_machine().

Reviewed-by: Steven Rostedt 
Reviewed-by: Masami Hiramatsu 
Signed-off-by: Jiri Kosina 
Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1307121120250.29788@pobox.suse.cz
Signed-off-by: H. Peter Anvin

jump_label, x86: Fix section mismatch

2011-12-06T19:41:02+00:00

WARNING: arch/x86/kernel/built-in.o(.text+0x4c71): Section mismatch in
reference from the function arch_jump_label_transform_static() to the
function .init.text:text_poke_early()
The function arch_jump_label_transform_static() references
the function __init text_poke_early().
This is often because arch_jump_label_transform_static lacks a __init
annotation or the annotation of text_poke_early is wrong.

Signed-off-by: Peter Zijlstra 
Cc: Jason Baron 
Link: http://lkml.kernel.org/n/tip-9lefe89mrvurrwpqw5h8xm8z@git.kernel.org
Signed-off-by: Ingo Molnar

x86/jump_label: add arch_jump_label_transform_static()

2011-10-25T18:54:42+00:00

This allows jump-label entries to be cheaply updated on code which is
not yet live.

Signed-off-by: Jeremy Fitzhardinge 
Acked-by: Jason Baron 
Acked-by: Peter Zijlstra

x86/jump_label: drop arch_jump_label_text_poke_early()

2011-10-25T18:54:21+00:00

It is no longer used.

Signed-off-by: Jeremy Fitzhardinge 
Acked-by: Jason Baron 
Acked-by: Peter Zijlstra

x86, cpu: Clean up and unify the NOP selection infrastructure

2011-04-18T23:40:21+00:00

Clean up and unify the NOP selection infrastructure:

- Make the atomic 5-byte NOP a part of the selection system.
- Pick NOPs once during early boot and then be done with it.

Signed-off-by: H. Peter Anvin 
Cc: Tejun Heo 
Cc: Steven Rostedt 
Cc: Frederic Weisbecker 
Cc: Jason Baron 
Link: http://lkml.kernel.org/r/1303166160-10315-3-git-send-email-hpa@linux.intel.com