Skip to content

cloud-kernel
cloud-kernel

openanolis / cloud-kernel
1 年多 前同步成功

通知 163
Star 36
Fork 7
cloud-kernel
cloud-kernel
切换分支/标签
  1. 04 7月, 2013 2 次提交
    • J
      mm/x86: use free_reserved_area() to simplify code · c88442ec
      由 Jiang Liu 提交于 
      Use common help function free_reserved_area() to simplify code.
Signed-off-by: NJiang Liu <jiang.liu@huawei.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Jianguo Wu <wujianguo@huawei.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: <sworddragon2@aol.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Michel Lespinasse <walken@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <tj@kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c88442ec
    • P
      mm: soft-dirty bits for user memory changes tracking · 0f8975ec
      由 Pavel Emelyanov 提交于 
      The soft-dirty is a bit on a PTE which helps to track which pages a task
writes to.  In order to do this tracking one should

  1. Clear soft-dirty bits from PTEs ("echo 4 > /proc/PID/clear_refs)
  2. Wait some time.
  3. Read soft-dirty bits (55'th in /proc/PID/pagemap2 entries)

To do this tracking, the writable bit is cleared from PTEs when the
soft-dirty bit is.  Thus, after this, when the task tries to modify a
page at some virtual address the #PF occurs and the kernel sets the
soft-dirty bit on the respective PTE.

Note, that although all the task's address space is marked as r/o after
the soft-dirty bits clear, the #PF-s that occur after that are processed
fast.  This is so, since the pages are still mapped to physical memory,
and thus all the kernel does is finds this fact out and puts back
writable, dirty and soft-dirty bits on the PTE.

Another thing to note, is that when mremap moves PTEs they are marked
with soft-dirty as well, since from the user perspective mremap modifies
the virtual memory at mremap's new address.
Signed-off-by: NPavel Emelyanov <xemul@parallels.com>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      0f8975ec
  3. 29 6月, 2013 1 次提交
  5. 28 6月, 2013 3 次提交
  7. 27 6月, 2013 3 次提交
  9. 26 6月, 2013 9 次提交
  11. 23 6月, 2013 6 次提交
    • B
      x86/platform: Add kvmconfig to the phony targets · fc58be75
      由 Borislav Petkov 提交于 
      ... so as not to disable it with a file of the same name in the
toplevel build directory.
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1371801891-23618-1-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      fc58be75
    • D
      x86: Add NMI duration tracepoints · 0c4df02d
      由 Dave Hansen 提交于 
      This patch has been invaluable in my adventures finding
issues in the perf NMI handler.  I'm as big a fan of
printk() as anybody is, but using printk() in NMIs is
deadly when they're happening frequently.

Even hacking in trace_printk() ended up eating enough
CPU to throw off some of the measurements I was making.
Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus@samba.org
Cc: acme@ghostprotocols.net
Cc: Dave Hansen <dave@sr71.net>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
      0c4df02d
    • D
      perf: Drop sample rate when sampling is too slow · 14c63f17
      由 Dave Hansen 提交于 
      This patch keeps track of how long perf's NMI handler is taking,
and also calculates how many samples perf can take a second.  If
the sample length times the expected max number of samples
exceeds a configurable threshold, it drops the sample rate.

This way, we don't have a runaway sampling process eating up the
CPU.

This patch can tend to drop the sample rate down to level where
perf doesn't work very well.  *BUT* the alternative is that my
system hangs because it spends all of its time handling NMIs.

I'll take a busted performance tool over an entire system that's
busted and undebuggable any day.

BTW, my suspicion is that there's still an underlying bug here.
Using the HPET instead of the TSC is definitely a contributing
factor, but I suspect there are some other things going on.
But, I can't go dig down on a bug like that with my machine
hanging all the time.
Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus@samba.org
Cc: acme@ghostprotocols.net
Cc: Dave Hansen <dave@sr71.net>
[ Prettified it a bit. ]
Signed-off-by: NIngo Molnar <mingo@kernel.org>
      14c63f17
    • D
      x86: Warn when NMI handlers take large amounts of time · 2ab00456
      由 Dave Hansen 提交于 
      I have a system which is causing all kinds of problems.  It has
8 NUMA nodes, and lots of cores that can fight over cachelines.
If things are not working _perfectly_, then NMIs can take longer
than expected.

If we get too many of them backed up to each other, we can
easily end up in a situation where we are doing nothing *but*
running NMIs.  The biggest problem, though, is that this happens
_silently_.  You might be lucky to get an hrtimer warning, but
most of the time system simply hangs.

This patch should at least give us some warning before we fall
off the cliff.  the warnings look like this:

	nmi_handle: perf_event_nmi_handler() took: 26095071 ns

The message is triggered whenever we notice the longest NMI
we've seen to date.  You can always view and reset this value
via the debugfs interface if you like.
Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus@samba.org
Cc: acme@ghostprotocols.net
Cc: Dave Hansen <dave@sr71.net>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
      2ab00456
    • S
      x86/tracing: Add config option checking to the definitions of mce handlers · 33e5ff63
      由 Seiji Aguchi 提交于 
      In case CONFIG_X86_MCE_THRESHOLD and CONFIG_X86_THERMAL_VECTOR
are disabled, kernel build fails as follows.

   arch/x86/built-in.o: In function `trace_threshold_interrupt':
   (.entry.text+0x122b): undefined reference to `smp_trace_threshold_interrupt'
   arch/x86/built-in.o: In function `trace_thermal_interrupt':
   (.entry.text+0x132b): undefined reference to `smp_trace_thermal_interrupt'

In this case, trace_threshold_interrupt/trace_thermal_interrupt
are not needed to define.

So, add config option checking to their definitions in entry_64.S.
Signed-off-by: NSeiji Aguchi <seiji.aguchi@hds.com>
Cc: rostedt@goodmis.org
Link: http://lkml.kernel.org/r/51C58B8A.2080808@hds.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      33e5ff63
    • S
      trace,x86: Do not call local_irq_save() in load_current_idt() · 2b4bc789
      由 Steven Rostedt (Red Hat) 提交于 
      As load_current_idt() is now what is used to update the IDT for the
switches needed for NMI, lockdep debug, and for tracing, it must not
call local_irq_save(). This is because one of the users of this is
lockdep, which does tracing of local_irq_save() and when the debug
trap is hit, we need to update the IDT before tracing interrupts
being disabled. As load_current_idt() is used to do this, calling
local_irq_save() which lockdep traces, defeats the point of calling
load_current_idt().

As interrupts are already disabled when used by lockdep and NMI, the
only other user is tracing that can disable interrupts itself. Simply
have the tracing update disable interrupts before calling load_current_idt()
instead of breaking the other users.

Here's the dump that happened:

------------[ cut here ]------------
WARNING: at /work/autotest/nobackup/linux-test.git/kernel/fork.c:1196 copy_process+0x2c3/0x1398()
DEBUG_LOCKS_WARN_ON(!p->hardirqs_enabled)
Modules linked in:
CPU: 1 PID: 4570 Comm: gdm-simple-gree Not tainted 3.10.0-rc3-test+ #5
Hardware name:                  /DG965MQ, BIOS MQ96510J.86A.0372.2006.0605.1717 06/05/2006
 ffffffff81d2a7a5 ffff88006ed13d50 ffffffff8192822b ffff88006ed13d90
 ffffffff81035f25 ffff8800721c6000 ffff88006ed13da0 0000000001200011
 0000000000000000 ffff88006ed5e000 ffff8800721c6000 ffff88006ed13df0
Call Trace:
 [<ffffffff8192822b>] dump_stack+0x19/0x1b
 [<ffffffff81035f25>] warn_slowpath_common+0x67/0x80
 [<ffffffff81035fe1>] warn_slowpath_fmt+0x46/0x48
 [<ffffffff812bfc5d>] ? __raw_spin_lock_init+0x31/0x52
 [<ffffffff810341f7>] copy_process+0x2c3/0x1398
 [<ffffffff8103539d>] do_fork+0xa8/0x260
 [<ffffffff810ca7b1>] ? trace_preempt_on+0x2a/0x2f
 [<ffffffff812afb3e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
 [<ffffffff81937fe7>] ? sysret_check+0x1b/0x56
 [<ffffffff81937fe7>] ? sysret_check+0x1b/0x56
 [<ffffffff810355cf>] SyS_clone+0x16/0x18
 [<ffffffff81938369>] stub_clone+0x69/0x90
 [<ffffffff81937fc2>] ? system_call_fastpath+0x16/0x1b
---[ end trace 8b157a9d20ca1aa2 ]---

in fork.c:

 #ifdef CONFIG_PROVE_LOCKING
	DEBUG_LOCKS_WARN_ON(!p->hardirqs_enabled); <-- bug here
	DEBUG_LOCKS_WARN_ON(!p->softirqs_enabled);
 #endif

Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
      2b4bc789
  13. 22 6月, 2013 1 次提交
    • A
      aout32 coredump compat fix · 945fb136
      由 Al Viro 提交于 
      dump_seek() does SEEK_CUR, not SEEK_SET; native binfmt_aout
handles it correctly (seeks by PAGE_SIZE - sizeof(struct user),
getting the current position to PAGE_SIZE), compat one seeks
by PAGE_SIZE and ends up at PAGE_SIZE + already written...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      945fb136
  15. 21 6月, 2013 10 次提交
    • S
      trace,x86: Move creation of irq tracepoints from apic.c to irq.c · 83ab8514
      由 Steven Rostedt (Red Hat) 提交于 
      Compiling without CONFIG_X86_LOCAL_APIC set, apic.c will not be
compiled, and the irq tracepoints will not be created via the
CREATE_TRACE_POINTS macro. When CONFIG_X86_LOCAL_APIC is not set,
we get the following build error:

  LD      init/built-in.o
arch/x86/built-in.o: In function `trace_x86_platform_ipi_entry':
linux-test.git/arch/x86/include/asm/trace/irq_vectors.h:66: undefined reference to `__tracepoint_x86_platform_ipi_entry'
arch/x86/built-in.o: In function `trace_x86_platform_ipi_exit':
linux-test.git/arch/x86/include/asm/trace/irq_vectors.h:66: undefined reference to `__tracepoint_x86_platform_ipi_exit'
arch/x86/built-in.o: In function `trace_irq_work_entry':
linux-test.git/arch/x86/include/asm/trace/irq_vectors.h:72: undefined reference to `__tracepoint_irq_work_entry'
arch/x86/built-in.o: In function `trace_irq_work_exit':
linux-test.git/arch/x86/include/asm/trace/irq_vectors.h:72: undefined reference to `__tracepoint_irq_work_exit'
arch/x86/built-in.o:(__jump_table+0x8): undefined reference to `__tracepoint_x86_platform_ipi_entry'
arch/x86/built-in.o:(__jump_table+0x14): undefined reference to `__tracepoint_x86_platform_ipi_exit'
arch/x86/built-in.o:(__jump_table+0x20): undefined reference to `__tracepoint_irq_work_entry'
arch/x86/built-in.o:(__jump_table+0x2c): undefined reference to `__tracepoint_irq_work_exit'
make[1]: *** [vmlinux] Error 1
make: *** [sub-make] Error 2

As irq.c is always compiled for x86, it is a more appropriate location
to create the irq tracepoints.

Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
      83ab8514
    • B
      x86/efi: Fix dummy variable buffer allocation · b8cb62f8
      由 Ben Hutchings 提交于 
      1. Check for allocation failure
2. Clear the buffer contents, as they may actually be written to flash
3. Don't leak the buffer

Compile-tested only.

[ Tested successfully on my buggy ASUS machine - Matt ]
Signed-off-by: NBen Hutchings <ben@decadent.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
      b8cb62f8
    • S
      x86, trace: Add irq vector tracepoints · cf910e83
      由 Seiji Aguchi 提交于 
      [Purpose of this patch]

As Vaibhav explained in the thread below, tracepoints for irq vectors
are useful.

http://www.spinics.net/lists/mm-commits/msg85707.html

<snip>
The current interrupt traces from irq_handler_entry and irq_handler_exit
provide when an interrupt is handled.  They provide good data about when
the system has switched to kernel space and how it affects the currently
running processes.

There are some IRQ vectors which trigger the system into kernel space,
which are not handled in generic IRQ handlers.  Tracing such events gives
us the information about IRQ interaction with other system events.

The trace also tells where the system is spending its time.  We want to
know which cores are handling interrupts and how they are affecting other
processes in the system.  Also, the trace provides information about when
the cores are idle and which interrupts are changing that state.
<snip>

On the other hand, my usecase is tracing just local timer event and
getting a value of instruction pointer.

I suggested to add an argument local timer event to get instruction pointer before.
But there is another way to get it with external module like systemtap.
So, I don't need to add any argument to irq vector tracepoints now.

[Patch Description]

Vaibhav's patch shared a trace point ,irq_vector_entry/irq_vector_exit, in all events.
But there is an above use case to trace specific irq_vector rather than tracing all events.
In this case, we are concerned about overhead due to unwanted events.

So, add following tracepoints instead of introducing irq_vector_entry/exit.
so that we can enable them independently.
   - local_timer_vector
   - reschedule_vector
   - call_function_vector
   - call_function_single_vector
   - irq_work_entry_vector
   - error_apic_vector
   - thermal_apic_vector
   - threshold_apic_vector
   - spurious_apic_vector
   - x86_platform_ipi_vector

Also, introduce a logic switching IDT at enabling/disabling time so that a time penalty
makes a zero when tracepoints are disabled. Detailed explanations are as follows.
 - Create trace irq handlers with entering_irq()/exiting_irq().
 - Create a new IDT, trace_idt_table, at boot time by adding a logic to
   _set_gate(). It is just a copy of original idt table.
 - Register the new handlers for tracpoints to the new IDT by introducing
   macros to alloc_intr_gate() called at registering time of irq_vector handlers.
 - Add checking, whether irq vector tracing is on/off, into load_current_idt().
   This has to be done below debug checking for these reasons.
   - Switching to debug IDT may be kicked while tracing is enabled.
   - On the other hands, switching to trace IDT is kicked only when debugging
     is disabled.

In addition, the new IDT is created only when CONFIG_TRACING is enabled to avoid being
used for other purposes.
Signed-off-by: NSeiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/51C323ED.5050708@hds.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
      cf910e83
    • S
      x86: Rename variables for debugging · 629f4f9d
      由 Seiji Aguchi 提交于 
      Rename variables for debugging to describe meaning of them precisely.

Also, introduce a generic way to switch IDT by checking a current state,
debug on/off.
Signed-off-by: NSeiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/51C323A8.7050905@hds.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
      629f4f9d
    • S
      x86, trace: Introduce entering/exiting_irq() · eddc0e92
      由 Seiji Aguchi 提交于 
      When implementing tracepoints in interrupt handers, if the tracepoints are
simply added in the performance sensitive path of interrupt handers,
it may cause potential performance problem due to the time penalty.

To solve the problem, an idea is to prepare non-trace/trace irq handers and
switch their IDTs at the enabling/disabling time.

So, let's introduce entering_irq()/exiting_irq() for pre/post-
processing of each irq handler.

A way to use them is as follows.

Non-trace irq handler:
smp_irq_handler()
{
	entering_irq();		/* pre-processing of this handler */
	__smp_irq_handler();	/*
				 * common logic between non-trace and trace handlers
				 * in a vector.
				 */
	exiting_irq();		/* post-processing of this handler */

}

Trace irq_handler:
smp_trace_irq_handler()
{
	entering_irq();		/* pre-processing of this handler */
	trace_irq_entry();	/* tracepoint for irq entry */
	__smp_irq_handler();	/*
				 * common logic between non-trace and trace handlers
				 * in a vector.
				 */
	trace_irq_exit();	/* tracepoint for irq exit */
	exiting_irq();		/* post-processing of this handler */

}

If tracepoints can place outside entering_irq()/exiting_irq() as follows,
it looks cleaner.

smp_trace_irq_handler()
{
	trace_irq_entry();
	smp_irq_handler();
	trace_irq_exit();
}

But it doesn't work.
The problem is with irq_enter/exit() being called. They must be called before
trace_irq_enter/exit(),  because of the rcu_irq_enter() must be called before
any tracepoints are used, as tracepoints use  rcu to synchronize.

As a possible alternative, we may be able to call irq_enter() first as follows
if irq_enter() can nest.

smp_trace_irq_hander()
{
	irq_entry();
	trace_irq_entry();
	smp_irq_handler();
	trace_irq_exit();
	irq_exit();
}

But it doesn't work, either.
If irq_enter() is nested, it may have a time penalty because it has to check if it
was already called or not. The time penalty is not desired in performance sensitive
paths even if it is tiny.
Signed-off-by: NSeiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/51C3238D.9040706@hds.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
      eddc0e92
    • H
      x86, reloc: Use xorl instead of xorq in relocate_kernel_64.S · f037e416
      由 H. Peter Anvin 提交于 
      There is no point in using "xorq" to clear a register... use "xorl" to
clear the bottom 32 bits, and the upper 32 bits get cleared by virtue
of zero extension.
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/n/tip-b76zi1gep39c0zs8fbvkhie9@git.kernel.org
      f037e416
    • B
      x86, fpu: Use static_cpu_has_safe before alternatives · 5f8c4218
      由 Borislav Petkov 提交于 
      The call stack below shows how this happens: basically eager_fpu_init()
calls __thread_fpu_begin(current) which then does if (!use_eager_fpu()),
which, in turn, uses static_cpu_has.

And we're executing before alternatives so static_cpu_has doesn't work
there yet.

Use the safe variant in this path which becomes optimal after
alternatives have run.

WARNING: at arch/x86/kernel/cpu/common.c:1368 warn_pre_alternatives+0x1e/0x20()
You're using static_cpu_has before alternatives have run!
Modules linked in:
Pid: 0, comm: swapper Not tainted 3.9.0-rc8+ #1
Call Trace:
 warn_slowpath_common
 warn_slowpath_fmt
 ? fpu_finit
 warn_pre_alternatives
 eager_fpu_init
 fpu_init
 cpu_init
 trap_init
 start_kernel
 ? repair_env_string
 x86_64_start_reservations
 x86_64_start_kernel
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1370772454-6106-6-git-send-email-bp@alien8.deSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
      5f8c4218
    • B
      x86: Add a static_cpu_has_safe variant · 4a90a99c
      由 Borislav Petkov 提交于 
      We want to use this in early code where alternatives might not have run
yet and for that case we fall back to the dynamic boot_cpu_has.

For that, force a 5-byte jump since the compiler could be generating
differently sized jumps for each label.
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1370772454-6106-5-git-send-email-bp@alien8.deSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
      4a90a99c
    • B
      x86: Sanity-check static_cpu_has usage · 5700f743
      由 Borislav Petkov 提交于 
      static_cpu_has may be used only after alternatives have run. Before that
it always returns false if constant folding with __builtin_constant_p()
doesn't happen. And you don't want that.

This patch is the result of me debugging an issue where I overzealously
put static_cpu_has in code which executed before alternatives have run
and had to spend some time with scratching head and cursing at the
monitor.

So add a jump to a warning which screams loudly when we use this
function too early. The alternatives patch that check away in
conjunction with patching the rest of the kernel image.

[ hpa: factored this into its own configuration option.  If we want to
  have an overarching option, it should be an option which selects
  other options, not as a group option in the source code. ]
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1370772454-6106-4-git-send-email-bp@alien8.deSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
      5700f743
    • B
      x86, cpu: Add a synthetic, always true, cpu feature · c3b83598
      由 Borislav Petkov 提交于 
      This will be used in alternatives later as an always-replace flag.
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1370772454-6106-2-git-send-email-bp@alien8.deSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
      c3b83598
  17. 20 6月, 2013 4 次提交
    • M
      kprobes: Fix arch_prepare_kprobe to handle copy insn failures · 003002e0
      由 Masami Hiramatsu 提交于 
      Fix arch_prepare_kprobe() to handle failures in copy instruction
correctly. This fix is related to the previous fix: 8101376d
which made __copy_instruction return an error result if failed,
but caller site was not updated to handle it. Thus, this is the
other half of the bugfix.

This fix is also related to the following bug-report:

   https://bugzilla.redhat.com/show_bug.cgi?id=910649Signed-off-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Tested-by: NJonathan Lebon <jlebon@redhat.com>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: systemtap@sourceware.org
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20130605031216.15285.2001.stgit@mhiramat-M0-7522Signed-off-by: NIngo Molnar <mingo@kernel.org>
      003002e0
    • M
      x86: Fix trigger_all_cpu_backtrace() implementation · b52e0a7c
      由 Michel Lespinasse 提交于 
      The following change fixes the x86 implementation of
trigger_all_cpu_backtrace(), which was previously (accidentally,
as far as I can tell) disabled to always return false as on
architectures that do not implement this function.

trigger_all_cpu_backtrace(), as defined in include/linux/nmi.h,
should call arch_trigger_all_cpu_backtrace() if available, or
return false if the underlying arch doesn't implement this
function.

x86 did provide a suitable arch_trigger_all_cpu_backtrace()
implementation, but it wasn't actually being used because it was
declared in asm/nmi.h, which linux/nmi.h doesn't include. Also,
linux/nmi.h couldn't easily be fixed by including asm/nmi.h,
because that file is not available on all architectures.

I am proposing to fix this by moving the x86 definition of
arch_trigger_all_cpu_backtrace() to asm/irq.h.

Tested via: echo l > /proc/sysrq-trigger

Before the change, this uses a fallback implementation which
shows backtraces on active CPUs (using
smp_call_function_interrupt() )

After the change, this shows NMI backtraces on all CPUs
Signed-off-by: NMichel Lespinasse <walken@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1370518875-1346-1-git-send-email-walken@google.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      b52e0a7c
    • B
      x86/intel/cacheinfo: Shut up last long-standing warning · 719038de
      由 Borislav Petkov 提交于 
      arch/x86/kernel/cpu/intel_cacheinfo.c: In function ‘init_intel_cacheinfo’:
arch/x86/kernel/cpu/intel_cacheinfo.c:642:28: warning: ‘this_leaf.size’ may be used uninitialized in this function [-Wmaybe-uninitialized] arch/x86/kernel/cpu/intel_cacheinfo.c:643:29: warning: ‘this_leaf.eax.split.num_threads_sharing’ may be used uninitialized in this function [-Wmaybe-uninitialized]

This keeps on happening during randbuilds and the compiler is
wrong here:

In the case where cpuid4_cache_lookup_regs() returns 0, both
this_leaf.size and this_leaf.eax get initialized. In the case
where the CPUID leaf doesn't contain valid cache info, we error
out which init_intel_cacheinfo() handles correctly without
touching the abovementioned fields.

So shut up the warning by clearing out the struct which we hand
down.

While at it, reverse error handling and gain one indentation
level.
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1370710095-20547-1-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      719038de
    • P
      x86: Fix section mismatch on load_ucode_ap · 94978599
      由 Paul Gortmaker 提交于 
      We are in the process of removing all the __cpuinit annotations.
While working on making that change, an existing problem was
made evident:

  WARNING: arch/x86/kernel/built-in.o(.text+0x198f2): Section mismatch
  in reference from the function cpu_init() to the function
  .init.text:load_ucode_ap()   The function cpu_init() references
  the function __init load_ucode_ap().  This is often because cpu_init
  lacks a __init annotation or the annotation of load_ucode_ap is wrong.

This now appears because in my working tree, cpu_init() is no longer
tagged as __cpuinit, and so the audit picks up the mismatch.  The 2nd
hypothesis from the audit is the correct one, as there was an incorrect
__init tag on the prototype in the header (but __cpuinit was used on
the function itself.)

The audit is telling us that the prototype's __init annotation took
effect and the function did land in the .init.text section.  Checking
with objdump on a mainline tree that still has __cpuinit shows that
the __cpuinit on the function takes precedence over the __init on the
prototype, but that won't be true once we make __cpuinit a no-op.

Even though we are removing __cpuinit, we temporarily align both
the function and the prototype on __cpuinit so that the changeset
can be applied to stable trees  if desired.

[ hpa: build fix only, no object code change ]

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: stable <stable@vger.kernel.org> # 3.9+
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Link: http://lkml.kernel.org/r/1371654926-11729-1-git-send-email-paul.gortmaker@windriver.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
      94978599
  19. 19 6月, 2013 1 次提交