pandora-kernel.git
11 years agoperf tools: Move all users of event_name to perf_evsel__name
Arnaldo Carvalho de Melo [Tue, 12 Jun 2012 15:34:58 +0000 (12:34 -0300)]
perf tools: Move all users of event_name to perf_evsel__name

So that we don't use global variables that could make us misreport event
names when having a multi window top, for instance.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-mccancovi1u0wdkg8ncth509@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
11 years agoperf evsel: Handle all event types in perf_evsel__name
Arnaldo Carvalho de Melo [Tue, 12 Jun 2012 13:29:12 +0000 (10:29 -0300)]
perf evsel: Handle all event types in perf_evsel__name

Now to convert all event_name users to perf_evsel__name.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-buuz0j0gynseglxa76r01rdn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
11 years agoperf tools: Reconstruct sw event with modifiers from perf_event_attr
Arnaldo Carvalho de Melo [Mon, 11 Jun 2012 17:36:20 +0000 (14:36 -0300)]
perf tools: Reconstruct sw event with modifiers from perf_event_attr

  [root@sandy ~]# perf record -e task-clock:u -a usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.482 MB perf.data (~21073 samples) ]
  [root@sandy ~]#

Before:

  [root@sandy ~]# perf evlist
  task-clock
  [root@sandy ~]#

After:

  [root@sandy ~]# perf evlist
  task-clock:u
  [root@sandy ~]#

Ditto for other tools.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-97ltkmj7v23kyhflltf6iz5n@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
11 years agoperf tools: Reconstruct hw cache event with modifiers from perf_event_attr
Arnaldo Carvalho de Melo [Mon, 11 Jun 2012 17:08:07 +0000 (14:08 -0300)]
perf tools: Reconstruct hw cache event with modifiers from perf_event_attr

  [root@sandy ~]# perf record -a -e dTLB-load-misses:u usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.486 MB perf.data (~21216 samples) ]

Before:

  [root@sandy ~]# perf evlist
  dTLB-load-misses
  [root@sandy ~]#

After:

  [root@sandy ~]# perf evlist
  dTLB-load-misses:u
  [root@sandy ~]#

Ditto for other tools.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-7x1b0e6jthkr93lfjzsuakk5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
11 years agoperf evsel: Carve out event modifier formatting
Arnaldo Carvalho de Melo [Mon, 11 Jun 2012 16:33:09 +0000 (13:33 -0300)]
perf evsel: Carve out event modifier formatting

From perf_evsel__hw_name, so that we can use it for the other kinds of
events (tracepoints, software, hw cache, etc).

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-9gmd5wewsrvtny8tzxjfp471@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
11 years agoperf hists browser: Implement printing snapshots to files
Arnaldo Carvalho de Melo [Thu, 7 Jun 2012 22:31:28 +0000 (19:31 -0300)]
perf hists browser: Implement printing snapshots to files

To avoid having to resort to --stdio, that expands everything, instead
allow the user to go on expanding the relevant callchains and then press
'P' to print that view.

As the hists browser is used for both static (report) and dynamic (top)
views, it prints to a 'perf.hists.N' sequence, i.e. multiple snapshots
can be taken in report and top.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-wr9xx4ba0utrynu5j6wotd79@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
11 years agoperf lib: Introduce rtrim
Arnaldo Carvalho de Melo [Thu, 7 Jun 2012 21:23:31 +0000 (18:23 -0300)]
perf lib: Introduce rtrim

Remove the trailing whitespaces.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-8bxozh5lyixgjmziqaxo9675@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
11 years agoperf ui/gtk: Use struct perf_error_ops
Namhyung Kim [Tue, 29 May 2012 04:23:02 +0000 (13:23 +0900)]
perf ui/gtk: Use struct perf_error_ops

Define and use perf_gtk_eops to provide a GTK2 message dialog for error
reporting and a info_bar for warning.

As GtkInfoBar requires recent GTK+ libraries, provides a fallback
implementation using statusbar widget too.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338265382-6872-8-git-send-email-namhyung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
11 years agoperf ui/gtk: Add GTK info_bar widget to browser window
Namhyung Kim [Tue, 29 May 2012 04:23:01 +0000 (13:23 +0900)]
perf ui/gtk: Add GTK info_bar widget to browser window

The GtkInfoBar is a modern UI component to display messages without
bothering the main window. It'll be used for showing a warning message.

As the GtkInfoBar requires 2.18 (or newer) version of GTK+ library, add
availability check to Makefile too.

Suggested-by: Sunjin Yang <fan4326@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338265382-6872-7-git-send-email-namhyung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
11 years agoperf ui/gtk: Add GTK statusbar widget to browser window
Namhyung Kim [Tue, 29 May 2012 04:23:00 +0000 (13:23 +0900)]
perf ui/gtk: Add GTK statusbar widget to browser window

Add statusbar widget to display non-critical messages at the bottom of
the window. This can be used for showing a status change, warning or
help message.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338265382-6872-6-git-send-email-namhyung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
11 years agoperf ui/gtk: Introduce struct perf_gtk_context
Namhyung Kim [Tue, 29 May 2012 04:22:59 +0000 (13:22 +0900)]
perf ui/gtk: Introduce struct perf_gtk_context

The struct perf_gtk_context is for tracking current state of GTK window
and/or other things. This is a preparation of next changes.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338265382-6872-5-git-send-email-namhyung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
11 years agoperf ui: Introduce struct perf_error_ops
Namhyung Kim [Tue, 29 May 2012 04:22:58 +0000 (13:22 +0900)]
perf ui: Introduce struct perf_error_ops

The struct perf_error_ops is for flexible error logging.

We can register appropriate functions based on front-end.

Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338265382-6872-4-git-send-email-namhyung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
11 years agoperf tools: Add sort by src line/number
Arnaldo Carvalho de Melo [Wed, 30 May 2012 13:33:24 +0000 (10:33 -0300)]
perf tools: Add sort by src line/number

Using addr2line for now, requires debuginfo, needs more work to support
detached debuginfo, aka foo-debuginfo packages.

Example:

[root@sandy ~]# perf record -a sleep 3
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.555 MB perf.data (~24236 samples) ]
[root@sandy ~]# perf report -s dso,srcline 2>&1 | grep -v ^# | head -5
    22.41%  [kernel.kallsyms]  /home/git/linux/drivers/idle/intel_idle.c:280
     4.79%  [kernel.kallsyms]  /home/git/linux/drivers/cpuidle/cpuidle.c:148
     4.78%  [kernel.kallsyms]  /home/git/linux/arch/x86/include/asm/atomic64_64.h:121
     4.49%  [kernel.kallsyms]  /home/git/linux/kernel/sched/core.c:1690
     4.30%  [kernel.kallsyms]  /home/git/linux/include/linux/seqlock.h:90
[root@sandy ~]#

[root@sandy ~]# perf top -U -s dso,symbol,srcline
Samples: 1K of event 'cycles', Event count (approx.): 589617389
 18.66%  [kernel]  [k] copy_user_generic_unrolled   /home/git/linux/arch/x86/lib/copy_user_64.S:143
  7.83%  [kernel]  [k] clear_page                   /home/git/linux/arch/x86/lib/clear_page_64.S:39
  6.59%  [kernel]  [k] clear_page                   /home/git/linux/arch/x86/lib/clear_page_64.S:38
  3.66%  [kernel]  [k] page_fault                   /home/git/linux/arch/x86/kernel/entry_64.S:1379
  3.25%  [kernel]  [k] clear_page                   /home/git/linux/arch/x86/lib/clear_page_64.S:40
  3.12%  [kernel]  [k] clear_page                   /home/git/linux/arch/x86/lib/clear_page_64.S:37
  2.74%  [kernel]  [k] clear_page                   /home/git/linux/arch/x86/lib/clear_page_64.S:36
  2.39%  [kernel]  [k] clear_page                   /home/git/linux/arch/x86/lib/clear_page_64.S:43
  2.12%  [kernel]  [k] ioread32                     /home/git/linux/lib/iomap.c:90
  1.51%  [kernel]  [k] copy_user_generic_unrolled   /home/git/linux/arch/x86/lib/copy_user_64.S:144
  1.19%  [kernel]  [k] copy_user_generic_unrolled   /home/git/linux/arch/x86/lib/copy_user_64.S:154

Suggested-by: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-pdmqbng9twz06jzkbgtuwbp8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
11 years agouprobes: Remove the unnecessary initialization in add_utask()
Oleg Nesterov [Fri, 15 Jun 2012 15:44:01 +0000 (17:44 +0200)]
uprobes: Remove the unnecessary initialization in add_utask()

Trivial cleanup. No need to nullify ->active_uprobe after
kzalloc().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120615154401.GA9633@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: __copy_insn() needs "loff_t offset"
Oleg Nesterov [Fri, 15 Jun 2012 15:43:59 +0000 (17:43 +0200)]
uprobes: __copy_insn() needs "loff_t offset"

1. __copy_insn() needs "loff_t offset", not "unsigned long",
   to read the file.

2. use pgoff_t for "idx" and remove the unnecessary typecast.

3. fix the typo, "&=" is not what we want

4. can't resist, rename off1 to off.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154359.GA9625@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Don't use loff_t for the valid virtual address
Oleg Nesterov [Fri, 15 Jun 2012 15:43:55 +0000 (17:43 +0200)]
uprobes: Don't use loff_t for the valid virtual address

loff_t looks confusing when it is used for the virtual address.
Change map_info and install_breakpoint/remove_breakpoint paths
to use "unsigned long".

The patch doesn't change vma_address(), it can't return "long"
because it is used to verify the mapping. But probably this
needs some cleanups too.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Arapov <anton@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154355.GA9622@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Simplify the usage of uprobe->pending_list
Oleg Nesterov [Fri, 15 Jun 2012 15:43:53 +0000 (17:43 +0200)]
uprobes: Simplify the usage of uprobe->pending_list

uprobe->pending_list is only used to create the temporary list,
it has no meaning after we drop uprobes_mmap_hash(inode).

No need to initialize this node or remove it from tmp_list, and
we can use list_for_each_entry().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120615154353.GA9614@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Move BUG_ON(UPROBE_SWBP_INSN_SIZE) from write_opcode() to install_breakpoint()
Oleg Nesterov [Fri, 15 Jun 2012 15:43:50 +0000 (17:43 +0200)]
uprobes: Move BUG_ON(UPROBE_SWBP_INSN_SIZE) from write_opcode() to install_breakpoint()

write_opcode() ensures that UPROBE_SWBP_INSN doesn't cross the
page boundary. This looks a bit confusing, the check does not
depend on vaddr and it is enough to do it only once right after
install_breakpoint()->arch_uprobe_analyze_insn().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154350.GA9611@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: No need to re-check vma_address() in write_opcode()
Oleg Nesterov [Fri, 15 Jun 2012 15:43:47 +0000 (17:43 +0200)]
uprobes: No need to re-check vma_address() in write_opcode()

write_opcode() is called by register_for_each_vma() and
uprobe_mmap() paths. In both cases the caller has already
verified this vaddr under mmap_sem, no need to re-check.

Note also that this check is wrong anyway, we should not
truncate loff_t returned by vma_address() if we do not trust
this mapping.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154347.GA9604@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Copy_insn() should not return -ENOMEM if __copy_insn() fails
Oleg Nesterov [Fri, 15 Jun 2012 15:43:44 +0000 (17:43 +0200)]
uprobes: Copy_insn() should not return -ENOMEM if __copy_insn() fails

copy_insn() returns -ENOMEM if the first __copy_insn() fails,
it should return the correct error code.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154344.GA9601@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Copy_insn() shouldn't depend on mm/vma/vaddr
Oleg Nesterov [Fri, 15 Jun 2012 15:43:42 +0000 (17:43 +0200)]
uprobes: Copy_insn() shouldn't depend on mm/vma/vaddr

1. copy_insn() doesn't need "addr", it can use uprobe->offset.
   Remove this argument.

2. Change copy_insn/__copy_insn to accept "struct file*" instead
   of vma.

copy_insn() is called only once and mm/vma/vaddr are random, it
shouldn't depend on them.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154342.GA9598@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Document uprobe_register() vs uprobe_mmap() race
Peter Zijlstra [Fri, 15 Jun 2012 15:43:39 +0000 (17:43 +0200)]
uprobes: Document uprobe_register() vs uprobe_mmap() race

Because the mind is treacherous and makes us forget we need to
write stuff down.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120615154339.GA9591@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Change build_map_info() to try kmalloc(GFP_NOWAIT) first
Oleg Nesterov [Fri, 15 Jun 2012 15:43:36 +0000 (17:43 +0200)]
uprobes: Change build_map_info() to try kmalloc(GFP_NOWAIT) first

build_map_info() doesn't allocate the memory under i_mmap_mutex
to avoid the deadlock with page reclaim. But it can try
GFP_NOWAIT first, it should work in the likely case and thus we
almost never need the pre-alloc-and-retry path.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Link: http://lkml.kernel.org/r/20120615154336.GA9588@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Rework register_for_each_vma() to make it O(n)
Oleg Nesterov [Fri, 15 Jun 2012 15:43:33 +0000 (17:43 +0200)]
uprobes: Rework register_for_each_vma() to make it O(n)

Currently register_for_each_vma() is O(n ** 2) + O(n ** 3),
every time find_next_vma_info() "restarts" the
vma_prio_tree_foreach() loop and each iteration rechecks the
whole try_list. This also means that try_list can grow
"indefinitely" if register/unregister races with munmap/mmap
activity even if the number of mapping is bounded at any time.

With this patch register_for_each_vma() builds the list of
mm/vaddr structures only once and does install_breakpoint() for
each entry.

We do not care about the new mappings which can be created after
build_map_info() drops mapping->i_mmap_mutex, uprobe_mmap()
should do its work.

Note that we do not allocate map_info under i_mmap_mutex, this
can deadlock with page reclaim (but see the next patch). So we
use 2 lists, "curr" which we are going to return, and "prev"
which holds the already allocated memory. The main loop deques
the entry from "prev" (initially it is empty), and if "prev"
becomes empty again it counts the number of entries we need to
pre-allocate outside of i_mmap_mutex.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Link: http://lkml.kernel.org/r/20120615154333.GA9581@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Install_breakpoint() should fail if is_swbp_insn() == T
Oleg Nesterov [Fri, 15 Jun 2012 15:43:31 +0000 (17:43 +0200)]
uprobes: Install_breakpoint() should fail if is_swbp_insn() == T

install_breakpoint() returns -EEXIST if is_swbp_insn(orig_insn)
== T, the caller treats this code as success.

This is doubly wrong. The successful return should set
UPROBE_COPY_INSN, but the real problem is that it shouldn't
succeed. If the probed insn is int3 the application should get
SIGTRAP, this won't happen with uprobe.

Probably we can fix this, we can add the UPROBE_SHARED_BP flag
and teach handle_swbp/set_orig_insn to handle this case
correctly. But this needs some complications and we have other
insns which can't be probed, lets make a simple fix for now.

I think this needs a cleanup. UPROBE_COPY_INSN should die,
copy_insn() should be called by alloc_uprobe().
arch_uprobe_analyze_insn() depends on ->mm (ia32_compat) but it
is called only once.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154331.GA9578@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Write_opcode()->__replace_page() can race with try_to_unmap()
Oleg Nesterov [Fri, 15 Jun 2012 15:43:28 +0000 (17:43 +0200)]
uprobes: Write_opcode()->__replace_page() can race with try_to_unmap()

write_opcode() gets old_page via get_user_pages() and then calls
__replace_page() which assumes that this old_page is still
mapped after pte_offset_map_lock().

This is not true if this old_page was already try_to_unmap()'ed,
and in this case everything __replace_page() does with old_page
is wrong. Just for example, put_page() is not balanced.

I think it is possible to teach __replace_page() to handle this
unlikely case correctly, but this patch simply changes it to use
page_check_address() and return -EAGAIN if it fails. The caller
should notice this error code and retry.

Note: write_opcode() asks for the cleanups, I'll try to do this
in a separate patch.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154328.GA9571@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: __copy_insn() should ensure a_ops->readpage != NULL
Oleg Nesterov [Fri, 15 Jun 2012 15:43:25 +0000 (17:43 +0200)]
uprobes: __copy_insn() should ensure a_ops->readpage != NULL

__copy_insn() blindly calls read_mapping_page(), this will crash
the kernel if ->readpage == NULL, add the necessary check. For
example, hugetlbfs_aops->readpage is NULL. Perhaps we should
change read_mapping_page() instead.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154325.GA9568@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Valid_vma() should reject VM_HUGETLB
Oleg Nesterov [Fri, 15 Jun 2012 15:43:22 +0000 (17:43 +0200)]
uprobes: Valid_vma() should reject VM_HUGETLB

__replace_page() obviously can't work with the hugetlbfs
mappings, uprobe_register() will likely crash the kernel. Change
valid_vma() to check VM_HUGETLB as well.

As for PageTransHuge() no need to worry, vma->vm_file != NULL.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154322.GA9561@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agoperf/x86: Convert obsolete simple_strtoul() usage to kstrtoul()
Shuah Khan [Mon, 11 Jun 2012 03:13:41 +0000 (21:13 -0600)]
perf/x86: Convert obsolete simple_strtoul() usage to kstrtoul()

Signed-off-by: Shuah Khan <shuahkhan@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1339384421.3025.8.camel@lorien2
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agoMerge tag 'v3.5-rc2' into perf/core
Ingo Molnar [Mon, 11 Jun 2012 08:51:35 +0000 (10:51 +0200)]
Merge tag 'v3.5-rc2' into perf/core

Merge in Linux 3.5-rc2 - to pick up fixes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agoLinux 3.5-rc2 v3.5-rc2
Linus Torvalds [Sat, 9 Jun 2012 01:40:09 +0000 (18:40 -0700)]
Linux 3.5-rc2

11 years agomm, oom: fix badness score underflow
David Rientjes [Fri, 8 Jun 2012 20:21:26 +0000 (13:21 -0700)]
mm, oom: fix badness score underflow

If the privileges given to root threads (3% of allowable memory) or a
negative value of /proc/pid/oom_score_adj happen to exceed the amount of
rss of a thread, its badness score overflows as a result of commit
a7f638f999ff ("mm, oom: normalize oom scores to oom_score_adj scale only
for userspace").

Fix this by making the type signed and return 1, meaning the thread is
still eligible for kill, if the value is negative.

Reported-by: Dave Jones <davej@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoMerge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Fri, 8 Jun 2012 21:59:29 +0000 (14:59 -0700)]
Merge branch 'sched-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull scheduler fixes from Ingo Molnar.

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Fix the relax_domain_level boot parameter
  sched: Validate assumptions in sched_init_numa()
  sched: Always initialize cpu-power
  sched: Fix domain iteration
  sched/rt: Fix lockdep annotation within find_lock_lowest_rq()
  sched/numa: Load balance between remote nodes
  sched/x86: Calculate booted cores after construction of sibling_mask

11 years agosched/fair: fix lots of kernel-doc warnings
Randy Dunlap [Fri, 8 Jun 2012 20:18:33 +0000 (13:18 -0700)]
sched/fair: fix lots of kernel-doc warnings

Fix lots of new kernel-doc warnings in kernel/sched/fair.c:

  Warning(kernel/sched/fair.c:3625): No description found for parameter 'env'
  Warning(kernel/sched/fair.c:3625): Excess function parameter 'sd' description in 'update_sg_lb_stats'
  Warning(kernel/sched/fair.c:3735): No description found for parameter 'env'
  Warning(kernel/sched/fair.c:3735): Excess function parameter 'sd' description in 'update_sd_pick_busiest'
  Warning(kernel/sched/fair.c:3735): Excess function parameter 'this_cpu' description in 'update_sd_pick_busiest'
  .. more warnings

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoRevert "drm/i915/crt: Do not rely upon the HPD presence pin"
Linus Torvalds [Fri, 8 Jun 2012 21:53:06 +0000 (14:53 -0700)]
Revert "drm/i915/crt: Do not rely upon the HPD presence pin"

This reverts commit 9e612a008fa7fe493a473454def56aa321479495.

It incorrectly finds VGA connectors where none are attached, apparently
not noticing that nothing replied to the EDID queries, and happily using
the default EDID modes that have nothing to do with actual hardware.

That in turn then causes X to fall down to the lowest common
denominator, which is usually the default 1024x768 mode that is in the
default EDID and pretty much anything supports).

I'd suggest that if not relying on the HDP pin, the code should at least
check whether it gets valid EDID data back, rather than just assume
there's something on the VGA connector.

Cc: Dave Airlie <airlied@linux.ie>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoMerge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso...
Linus Torvalds [Fri, 8 Jun 2012 18:15:31 +0000 (11:15 -0700)]
Merge tag 'ext4_for_linus' of git://git./linux/kernel/git/tytso/ext4

Pull ext4 bug fixes from Theodore Ts'o:
 "This update contains two bug fixes, both destined for the stable tree.
  Perhaps the most important is one which fixes ext4 when used with file
  systems originally formatted for use with ext3, but then later
  converted to take advantage of ext4."

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: don't set i_flags in EXT4_IOC_SETFLAGS
  ext4: fix the free blocks calculation for ext3 file systems w/ uninit_bg

11 years agoMerge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
Linus Torvalds [Fri, 8 Jun 2012 18:06:01 +0000 (11:06 -0700)]
Merge branch 'merge' of git://git./linux/kernel/git/paulus/powerpc

Pull powerpc fixes from Paul Mackerras:
 "Two small fixes for powerpc:
   - a fix for a regression since 3.2 that causes 4-second (or longer)
     pauses
   - a fix for a potential oops when loading kernel modules on 32-bit
     embedded systems."

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
  powerpc: Fix kernel panic during kernel module load
  powerpc/time: Sanity check of decrementer expiration is necessary

11 years agoMerge tag 'upstream-3.5-rc2' of git://git.infradead.org/linux-ubifs
Linus Torvalds [Fri, 8 Jun 2012 18:04:06 +0000 (11:04 -0700)]
Merge tag 'upstream-3.5-rc2' of git://git.infradead.org/linux-ubifs

Pull UBI/UBIFS fixes from Artem Bityutskiy:
 "Fix UBI and UBIFS - they refuse to work without debugfs.  This was
  broken by the 3.5-rc1 UBI/UBIFS changes when we removed the debugging
  Kconfig switches.

  Also, correct locking in 'ubi_wl_flush()' - it was extended to support
  flushing a specific LEB in 3.5-rc1, and the locking was sub-optimal."

* tag 'upstream-3.5-rc2' of git://git.infradead.org/linux-ubifs:
  UBI: correct ubi_wl_flush locking
  UBIFS: fix debugfs-less systems support
  UBI: fix debugfs-less systems support

11 years agoRevert "vfs: stop d_splice_alias creating directory aliases"
Linus Torvalds [Fri, 8 Jun 2012 17:34:03 +0000 (10:34 -0700)]
Revert "vfs: stop d_splice_alias creating directory aliases"

This reverts commit 7732a557b1342c6e6966efb5f07effcf99f56167 (and commit
3f50fff4dace23d3cfeb195d5cd4ee813cee68b7, which was a follow-up
cleanup).

We're chasing an elusive bug that Dave Jones can apparently reproduce
using his system call fuzzer tool, and that looks like some kind of
locking ordering problem on the directory i_mutex chain.  Our i_mutex
locking is rather complex, and depends on the topological ordering of
the directories, which is why we have been very wary of splicing
directory entries around.

Of course, we really don't want to ever see aliased unconnected
directories anyway, so none of this should ever happen, but this revert
aims to basically get us back to a known older state.

Bruce points to some of the previous discussion at

       http://marc.info/?i=<20110310105821.GE22723@ZenIV.linux.org.uk>

and in particular a long post from Neil:

       http://marc.info/?i=<20110311150749.2fa2be66@notabene.brown>

It should be noted that it's possible that Dave's problems come from
other changes altohgether, including possibly just the fact that Dave
constantly is teachning his fuzzer new tricks.  So what appears to be a
new bug could in fact be an old one that just gets newly triggered, but
reverting these patches as "still under heavy discussion" is the right
thing regardless.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoMerge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Fri, 8 Jun 2012 16:26:55 +0000 (09:26 -0700)]
Merge branch 'x86-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull x86 fixes from Ingo Molnar.

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/nmi: Fix section mismatch warnings on 32-bit
  x86/uv: Fix UV2 BAU legacy mode
  x86/mm: Only add extra pages count for the first memory range during pre-allocation early page table space
  x86, efi stub: Add .reloc section back into image
  x86/ioapic: Fix NULL pointer dereference on CPU hotplug after disabling irqs
  x86/reboot: Fix a warning message triggered by stop_other_cpus()
  x86/intel/moorestown: Change intel_scu_devices_create() to __devinit
  x86/numa: Set numa_nodes_parsed at acpi_numa_memory_affinity_init()
  x86/gart: Fix kmemleak warning
  x86: mce: Add the dropped timer interval init back
  x86/mce: Fix the MCE poll timer logic

11 years agoMerge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Fri, 8 Jun 2012 16:14:46 +0000 (09:14 -0700)]
Merge branch 'perf-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull perf fixes from Ingo Molnar:
 "A bit larger than what I'd wish for - half of it is due to hw driver
  updates to Intel Ivy-Bridge which info got recently released,
  cycles:pp should work there now too, amongst other things.  (but we
  are generally making exceptions for hardware enablement of this type.)

  There are also callchain fixes in it - responding to mostly
  theoretical (but valid) concerns.  The tooling side sports perf.data
  endianness/portability fixes which did not make it for the merge
  window - and various other fixes as well."

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
  perf/x86: Check user address explicitly in copy_from_user_nmi()
  perf/x86: Check if user fp is valid
  perf: Limit callchains to 127
  perf/x86: Allow multiple stacks
  perf/x86: Update SNB PEBS constraints
  perf/x86: Enable/Add IvyBridge hardware support
  perf/x86: Implement cycles:p for SNB/IVB
  perf/x86: Fix Intel shared extra MSR allocation
  x86/decoder: Fix bsr/bsf/jmpe decoding with operand-size prefix
  perf: Remove duplicate invocation on perf_event_for_each
  perf uprobes: Remove unnecessary check before strlist__delete
  perf symbols: Check for valid dso before creating map
  perf evsel: Fix 32 bit values endianity swap for sample_id_all header
  perf session: Handle endianity swap on sample_id_all header data
  perf symbols: Handle different endians properly during symbol load
  perf evlist: Pass third argument to ioctl explicitly
  perf tools: Update ioctl documentation for PERF_IOC_FLAG_GROUP
  perf tools: Make --version show kernel version instead of pull req tag
  perf tools: Check if callchain is corrupted
  perf callchain: Make callchain cursors TLS
  ...

11 years agoMerge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Linus Torvalds [Fri, 8 Jun 2012 16:12:21 +0000 (09:12 -0700)]
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux

Pull drm intel and exynos fixes from Dave Airlie:
 "A bunch of fixes for Intel and exynos, nothing too major, a new intel
  PCI ID, and a fix for CRT detection."

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/i915: pch_irq_handler -> {ibx, cpt}_irq_handler
  char/agp: add another Ironlake host bridge
  drm/i915: fix up ivb plane 3 pageflips
  drm/exynos: fixed blending for hdmi graphic layer
  drm/exynos: Remove dummy encoder get_crtc operation implementation
  drm/exynos: Keep a reference to frame buffer GEM objects
  drm/exynos: Don't cast GEM object to Exynos GEM object when not needed
  drm/exynos: DRIVER_BUS_PLATFORM is not a driver feature
  drm/exynos: fixed size type.
  drm/exynos: Use DRM_FORMAT_{NV12, YUV420} instead of DRM_FORMAT_{NV12M, YUV420M}
  drm/i915: hold forcewake around ring hw init
  drm/i915: Mark the ringbuffers as being in the GTT domain
  drm/i915/crt: Do not rely upon the HPD presence pin
  drm/i915: Reset last_retired_head when resetting ring

11 years agoMerge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Fri, 8 Jun 2012 16:11:33 +0000 (09:11 -0700)]
Merge branch 'timers-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull leap second timer fix from Thomas Gleixner.

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timekeeping: Fix CLOCK_MONOTONIC inconsistency during leapsecond

11 years agoMerge tag 'moduleparam-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Fri, 8 Jun 2012 16:10:35 +0000 (09:10 -0700)]
Merge tag 'moduleparam-for-linus' of git://git./linux/kernel/git/rusty/linux-2.6-for-linus

Pull minor module param fixes from Rusty Russell:
 "One bugfix for multiple moduleparam levels, one removal of overzealous
  printk."

* tag 'moduleparam-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  init: Drop initcall level output
  module_param: stop double-calling parameters.

11 years agouprobes: Pass probed vaddr to arch_uprobe_analyze_insn()
Ananth N Mavinakayanahalli [Fri, 8 Jun 2012 09:32:57 +0000 (15:02 +0530)]
uprobes: Pass probed vaddr to arch_uprobe_analyze_insn()

On RISC architectures like powerpc, instructions are fixed size.
Instruction analysis on such platforms is just a matter of
(insn % 4). Pass the vaddr at which the uprobe is to be inserted so
that arch_uprobe_analyze_insn() can flag misaligned registration
requests.

Signed-off-by: Ananth N Mavinakaynahalli <ananth@in.ibm.com>
Cc: michael@ellerman.id.au
Cc: antonb@thinktux.localdomain
Cc: Paul Mackerras <paulus@samba.org>
Cc: benh@kernel.crashing.org
Cc: peterz@infradead.org
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: oleg@redhat.com
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/20120608093257.GG13409@in.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agox86/nmi: Fix section mismatch warnings on 32-bit
Don Zickus [Wed, 6 Jun 2012 14:05:42 +0000 (10:05 -0400)]
x86/nmi: Fix section mismatch warnings on 32-bit

It was reported that compiling for 32-bit caused a bunch of
section mismatch warnings:

 VDSOSYM arch/x86/vdso/vdso32-syms.lds
  LD      arch/x86/vdso/built-in.o
  LD      arch/x86/built-in.o

 WARNING: arch/x86/built-in.o(.data+0x5af0): Section mismatch in
 reference from the variable test_nmi_ipi_callback_na.10451 to
 the function .init.text:test_nmi_ipi_callback() [...]

 WARNING: arch/x86/built-in.o(.data+0x5b04): Section mismatch in
 reference from the variable nmi_unk_cb_na.10399 to the function
 .init.text:nmi_unk_cb() The variable nmi_unk_cb_na.10399
 references the function __init nmi_unk_cb() [...]

Both of these are attributed to the internal representation of
the nmiaction struct created during register_nmi_handler.  The
reason for this is that those structs are not defined in the
init section whereas the rest of the code in nmi_selftest.c is.

To resolve this, I created a new #define,
register_nmi_handler_initonly, that tags the struct as
__initdata to resolve the mismatch.  This #define should only be
used in rare situations where the register/unregister is called
during init of the kernel.

Big thanks to Jan Beulich for decoding this for me as I didn't
have a clue what was going on.

Reported-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
Tested-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
Cc: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/1338991542-23000-1-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agopowerpc: Fix kernel panic during kernel module load
Steffen Rumler [Wed, 6 Jun 2012 14:37:17 +0000 (16:37 +0200)]
powerpc: Fix kernel panic during kernel module load

This fixes a problem which can causes kernel oopses while loading
a kernel module.

According to the PowerPC EABI specification, GPR r11 is assigned
the dedicated function to point to the previous stack frame.
In the powerpc-specific kernel module loader, do_plt_call()
(in arch/powerpc/kernel/module_32.c), GPR r11 is also used
to generate trampoline code.

This combination crashes the kernel, in the case where the compiler
chooses to use a helper function for saving GPRs on entry, and the
module loader has placed the .init.text section far away from the
.text section, meaning that it has to generate a trampoline for
functions in the .init.text section to call the GPR save helper.
Because the trampoline trashes r11, references to the stack frame
using r11 can cause an oops.

The fix just uses GPR r12 instead of GPR r11 for generating the
trampoline code.  According to the statements from Freescale, this is
safe from an EABI perspective.

I've tested the fix for kernel 2.6.33 on MPC8541.

Cc: stable@vger.kernel.org
Signed-off-by: Steffen Rumler <steffen.rumler.ext@nsn.com>
[paulus@samba.org: reworded the description]
Signed-off-by: Paul Mackerras <paulus@samba.org>
11 years agox86/uv: Fix UV2 BAU legacy mode
Cliff Wickman [Thu, 7 Jun 2012 13:31:40 +0000 (08:31 -0500)]
x86/uv: Fix UV2 BAU legacy mode

The SGI Altix UV2 BAU (Broadcast Assist Unit) as used for
tlb-shootdown (selective broadcast mode) always uses UV2
broadcast descriptor format. There is no need to clear the
'legacy' (UV1) mode, because the hardware always uses UV2 mode
for selective broadcast.

But the BIOS uses general broadcast and legacy mode, and the
hardware pays attention to the legacy mode bit for general
broadcast. So the kernel must not clear that mode bit.

Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/E1SccoO-0002Lh-Cb@eag09.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agox86/mm: Only add extra pages count for the first memory range during pre-allocation...
Yinghai Lu [Wed, 6 Jun 2012 17:55:40 +0000 (10:55 -0700)]
x86/mm: Only add extra pages count for the first memory range during pre-allocation early page table space

Robin found this regression:

| I just tried to boot an 8TB system.  It fails very early in boot with:
| Kernel panic - not syncing: Cannot find space for the kernel page tables

git bisect commit 722bc6b16771ed80871e1fd81c86d3627dda2ac8.

A git revert of that commit does boot past that point on the 8TB
configuration.

That commit will add up extra pages for all memory range even
above 4g.

Try to limit that extra page count adding to first entry only.

Bisected-by: Robin Holt <holt@sgi.com>
Tested-by: Robin Holt <holt@sgi.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/CAE9FiQUj3wyzQxtq9yzBNc9u220p8JZ1FYHG7t%3DMOzJ%3D9BZMYA@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agoMerge branch 'exynos-drm-fixes' of git://git.infradead.org/users/kmpark/linux-samsung...
Dave Airlie [Fri, 8 Jun 2012 08:42:51 +0000 (09:42 +0100)]
Merge branch 'exynos-drm-fixes' of git://git.infradead.org/users/kmpark/linux-samsung into drm-fixes

* 'exynos-drm-fixes' of git://git.infradead.org/users/kmpark/linux-samsung:
  drm/exynos: fixed blending for hdmi graphic layer
  drm/exynos: Remove dummy encoder get_crtc operation implementation
  drm/exynos: Keep a reference to frame buffer GEM objects
  drm/exynos: Don't cast GEM object to Exynos GEM object when not needed
  drm/exynos: DRIVER_BUS_PLATFORM is not a driver feature
  drm/exynos: fixed size type.
  drm/exynos: Use DRM_FORMAT_{NV12, YUV420} instead of DRM_FORMAT_{NV12M, YUV420M}

11 years agoMerge branch 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel...
Dave Airlie [Fri, 8 Jun 2012 08:42:35 +0000 (09:42 +0100)]
Merge branch 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel into drm-fixes

* 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel:
  drm/i915: pch_irq_handler -> {ibx, cpt}_irq_handler
  char/agp: add another Ironlake host bridge
  drm/i915: fix up ivb plane 3 pageflips
  drm/i915: hold forcewake around ring hw init
  drm/i915: Mark the ringbuffers as being in the GTT domain
  drm/i915/crt: Do not rely upon the HPD presence pin
  drm/i915: Reset last_retired_head when resetting ring

11 years agoinit: Drop initcall level output
Borislav Petkov [Fri, 1 Jun 2012 16:56:00 +0000 (18:56 +0200)]
init: Drop initcall level output

9fb48c744ba6a ("params: add 3rd arg to option handler callback
signature") added similar lines to dmesg:

initlevel:0=early, 4 registered initcalls
initlevel:1=core, 31 registered initcalls
initlevel:2=postcore, 11 registered initcalls
initlevel:3=arch, 7 registered initcalls
initlevel:4=subsys, 40 registered initcalls
initlevel:5=fs, 30 registered initcalls
initlevel:6=device, 250 registered initcalls
initlevel:7=late, 35 registered initcalls

but they don't contain any info for the general user staring at dmesg.
I'm very doubtful the count of initcalls registered per level helps
anyone so drop that output completely.

Cc: Jim Cromie <jim.cromie@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jason Baron <jbaron@redhat.com>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
11 years agomodule_param: stop double-calling parameters.
Rusty Russell [Fri, 8 Jun 2012 05:28:13 +0000 (14:58 +0930)]
module_param: stop double-calling parameters.

Commit 026cee0086fe1df4cf74691cf273062cc769617d "params:
<level>_initcall-like kernel parameters" set old-style module
parameters to level 0.  And we call those level 0 calls where we used
to, early in start_kernel().

We also loop through the initcall levels and call the levelled
module_params before the corresponding initcall.  Unfortunately level
0 is early_init(), so we call the standard module_param calls twice.

(Turns out most things don't care, but at least ubi.mtd does).

Change the level to -1 for standard module_param calls.

Reported-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org
11 years agopowerpc/time: Sanity check of decrementer expiration is necessary
Paul Mackerras [Fri, 1 Jun 2012 08:13:43 +0000 (18:13 +1000)]
powerpc/time: Sanity check of decrementer expiration is necessary

This reverts 68568add2c ("powerpc/time: Remove unnecessary sanity check
of decrementer expiration").  We do need to check whether we have reached
the expiration time of the next event, because we sometimes get an early
decrementer interrupt, most notably when we set the decrementer to 1 in
arch_irq_work_raise().  The effect of not having the sanity check is that
if timer_interrupt() gets called early, we leave the decrementer set to
its maximum value, which means we then don't get any more decrementer
interrupts for about 4 seconds (or longer, depending on timebase
frequency).  I saw these pauses as a consequence of getting a stray
hypervisor decrementer interrupt left over from exiting a KVM guest.

This isn't quite a straight revert because of changes to the surrounding
code, but it restores the same algorithm as was previously used.

Cc: stable@vger.kernel.org
Acked-by: Anton Blanchard <anton@samba.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
11 years agoRevert "mm: correctly synchronize rss-counters at exit/exec"
Linus Torvalds [Fri, 8 Jun 2012 00:54:07 +0000 (17:54 -0700)]
Revert "mm: correctly synchronize rss-counters at exit/exec"

This reverts commit 40af1bbdca47e5c8a2044039bb78ca8fd8b20f94.

It's horribly and utterly broken for at least the following reasons:

 - calling sync_mm_rss() from mmput() is fundamentally wrong, because
   there's absolutely no reason to believe that the task that does the
   mmput() always does it on its own VM.  Example: fork, ptrace, /proc -
   you name it.

 - calling it *after* having done mmdrop() on it is doubly insane, since
   the mm struct may well be gone now.

 - testing mm against NULL before you call it is insane too, since a
NULL mm there would have caused oopses long before.

.. and those are just the three bugs I found before I decided to give up
looking for me and revert it asap.  I should have caught it before I
even took it, but I trusted Andrew too much.

Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoext4: don't set i_flags in EXT4_IOC_SETFLAGS
Tao Ma [Thu, 7 Jun 2012 23:04:19 +0000 (19:04 -0400)]
ext4: don't set i_flags in EXT4_IOC_SETFLAGS

Commit 7990696 uses the ext4_{set,clear}_inode_flags() functions to
change the i_flags automatically but fails to remove the error setting
of i_flags.  So we still have the problem of trashing state flags.
Fix this by removing the assignment.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
11 years agoext4: fix the free blocks calculation for ext3 file systems w/ uninit_bg
Theodore Ts'o [Thu, 7 Jun 2012 22:56:06 +0000 (18:56 -0400)]
ext4: fix the free blocks calculation for ext3 file systems w/ uninit_bg

Ext3 filesystems that are converted to use as many ext4 file system
features as possible will enable uninit_bg to speed up e2fsck times.
These file systems will have a native ext3 layout of inode tables and
block allocation bitmaps (as opposed to ext4's flex_bg layout).
Unfortunately, in these cases, when first allocating a block in an
uninitialized block group, ext4 would incorrectly calculate the number
of free blocks in that block group, and then errorneously report that
the file system was corrupt:

EXT4-fs error (device vdd): ext4_mb_generate_buddy:741: group 30, 32254 clusters in bitmap, 32258 in gd

This problem can be reproduced via:

    mke2fs -q -t ext4 -O ^flex_bg /dev/vdd 5g
    mount -t ext4 /dev/vdd /mnt
    fallocate -l 4600m /mnt/test

The problem was caused by a bone headed mistake in the check to see if a
particular metadata block was part of the block group.

Many thanks to Kees Cook for finding and bisecting the buggy commit
which introduced this bug (commit fd034a84e1, present since v3.2).

Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Reported-by: Kees Cook <keescook@chromium.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Tested-by: Kees Cook <keescook@chromium.org>
Cc: stable@kernel.org
11 years agoMerge branch 'akpm' (Andrew's fixups)
Linus Torvalds [Thu, 7 Jun 2012 22:05:43 +0000 (15:05 -0700)]
Merge branch 'akpm' (Andrew's fixups)

Merge random fixes from Andrew Morton.

* emailed from Andrew Morton <akpm@linux-foundation.org>: (11 patches)
  mm: correctly synchronize rss-counters at exit/exec
  btree: catch NULL value before it does harm
  btree: fix tree corruption in btree_get_prev()
  ipc: shm: restore MADV_REMOVE functionality on shared memory segments
  drivers/platform/x86/acerhdf.c: correct Boris' mail address
  c/r: prctl: drop VMA flags test on PR_SET_MM_ stack data assignment
  c/r: prctl: add ability to get clear_tid_address
  c/r: prctl: add minimal address test to PR_SET_MM
  c/r: prctl: update prctl_set_mm_exe_file() after mm->num_exe_file_vmas removal
  MAINTAINERS: whitespace fixes
  shmem: replace_page must flush_dcache and others

11 years agomm: correctly synchronize rss-counters at exit/exec
Konstantin Khlebnikov [Thu, 7 Jun 2012 21:21:14 +0000 (14:21 -0700)]
mm: correctly synchronize rss-counters at exit/exec

mm->rss_stat counters have per-task delta: task->rss_stat.  Before
changing task->mm pointer the kernel must flush this delta with
sync_mm_rss().

do_exit() already calls sync_mm_rss() to flush the rss-counters before
committing the rss statistics into task->signal->maxrss, taskstats,
audit and other stuff.  Unfortunately the kernel does this before
calling mm_release(), which can call put_user() for processing
task->clear_child_tid.  So at this point we can trigger page-faults and
task->rss_stat becomes non-zero again.  As a result mm->rss_stat becomes
inconsistent and check_mm() will print something like this:

| BUG: Bad rss-counter state mm:ffff88020813c380 idx:1 val:-1
| BUG: Bad rss-counter state mm:ffff88020813c380 idx:2 val:1

This patch moves sync_mm_rss() into mm_release(), and moves mm_release()
out of do_exit() and calls it earlier.  After mm_release() there should
be no pagefaults.

[akpm@linux-foundation.org: tweak comment]
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@vger.kernel.org> [3.4.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agobtree: catch NULL value before it does harm
Joern Engel [Thu, 7 Jun 2012 21:21:14 +0000 (14:21 -0700)]
btree: catch NULL value before it does harm

Storing NULL values in the btree is illegal and can lead to memory
corruption and possible other fun as well.  Catch it on insert, instead
of waiting for the inevitable.

Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agobtree: fix tree corruption in btree_get_prev()
Roland Dreier [Thu, 7 Jun 2012 21:21:13 +0000 (14:21 -0700)]
btree: fix tree corruption in btree_get_prev()

The memory the parameter __key points to is used as an iterator in
btree_get_prev(), so if we save off a bkey() pointer in retry_key and
then assign that to __key, we'll end up corrupting the btree internals
when we do eg

longcpy(__key, bkey(geo, node, i), geo->keylen);

to return the key value.  What we should do instead is use longcpy() to
copy the key value that retry_key points to __key.

This can cause a btree to get corrupted by seemingly read-only
operations such as btree_for_each_safe.

[akpm@linux-foundation.org: avoid the double longcpy()]
Signed-off-by: Roland Dreier <roland@purestorage.com>
Acked-by: Joern Engel <joern@logfs.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoipc: shm: restore MADV_REMOVE functionality on shared memory segments
Will Deacon [Thu, 7 Jun 2012 21:21:13 +0000 (14:21 -0700)]
ipc: shm: restore MADV_REMOVE functionality on shared memory segments

Commit 17cf28afea2a ("mm/fs: remove truncate_range") removed the
truncate_range inode operation in favour of the fallocate file
operation.

When using SYSV IPC shared memory segments, calling madvise with the
MADV_REMOVE advice on an area of shared memory will attempt to invoke
the .fallocate function for the shm_file_operations, which is NULL and
therefore returns -EOPNOTSUPP to userspace.  The previous behaviour
would inherit the inode_operations from the underlying tmpfs file and
invoke truncate_range there.

This patch restores the previous behaviour by wrapping the underlying
fallocate function in shm_fallocate, as we do for fsync.

[hughd@google.com: use -ENOTSUPP in shm_fallocate()]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agodrivers/platform/x86/acerhdf.c: correct Boris' mail address
Borislav Petkov [Thu, 7 Jun 2012 21:21:12 +0000 (14:21 -0700)]
drivers/platform/x86/acerhdf.c: correct Boris' mail address

Correct mail address reference to a mail account which I actually read.

Signed-off-by: Borislav Petkov <bp@alien8.de>
Cc: Peter Feuerer <peter@piie.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoc/r: prctl: drop VMA flags test on PR_SET_MM_ stack data assignment
Cyrill Gorcunov [Thu, 7 Jun 2012 21:21:12 +0000 (14:21 -0700)]
c/r: prctl: drop VMA flags test on PR_SET_MM_ stack data assignment

In commit b76437579d13 ("procfs: mark thread stack correctly in
proc/<pid>/maps") the stack allocated via clone() is marked in
/proc/<pid>/maps as [stack:%d] thus it might be out of the former
mm->start_stack/end_stack values (and even has some custom VMA flags
set).

So to be able to restore mm->start_stack/end_stack drop vma flags test,
but still require the underlying VMA to exist.

As always note this feature is under CONFIG_CHECKPOINT_RESTORE and
requires CAP_SYS_RESOURCE to be granted.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoc/r: prctl: add ability to get clear_tid_address
Cyrill Gorcunov [Thu, 7 Jun 2012 21:21:12 +0000 (14:21 -0700)]
c/r: prctl: add ability to get clear_tid_address

Zero is written at clear_tid_address when the process exits.  This
functionality is used by pthread_join().

We already have sys_set_tid_address() to change this address for the
current task but there is no way to obtain it from user space.

Without the ability to find this address and dump it we can't restore
pthread'ed apps which call pthread_join() once they have been restored.

This patch introduces the PR_GET_TID_ADDRESS prctl option which allows
the current process to obtain own clear_tid_address.

This feature is available iif CONFIG_CHECKPOINT_RESTORE is set.

[akpm@linux-foundation.org: fix prctl numbering]
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pedro Alves <palves@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Tejun Heo <tj@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoc/r: prctl: add minimal address test to PR_SET_MM
Cyrill Gorcunov [Thu, 7 Jun 2012 21:21:11 +0000 (14:21 -0700)]
c/r: prctl: add minimal address test to PR_SET_MM

Make sure the address being set is greater than mmap_min_addr (as
suggested by Kees Cook).

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoc/r: prctl: update prctl_set_mm_exe_file() after mm->num_exe_file_vmas removal
Konstantin Khlebnikov [Thu, 7 Jun 2012 21:21:11 +0000 (14:21 -0700)]
c/r: prctl: update prctl_set_mm_exe_file() after mm->num_exe_file_vmas removal

A fix for commit b32dfe377102 ("c/r: prctl: add ability to set new
mm_struct::exe_file").

After removing mm->num_exe_file_vmas kernel keeps mm->exe_file until
final mmput(), it never becomes NULL while task is alive.

We can check for other mapped files in mm instead of checking
mm->num_exe_file_vmas, and mark mm with flag MMF_EXE_FILE_CHANGED in
order to forbid second changing of mm->exe_file.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoMAINTAINERS: whitespace fixes
Joe Perches [Thu, 7 Jun 2012 21:21:10 +0000 (14:21 -0700)]
MAINTAINERS: whitespace fixes

Remove trailing spaces at EOL.
Always use a tab after the type :

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoshmem: replace_page must flush_dcache and others
Hugh Dickins [Thu, 7 Jun 2012 21:21:09 +0000 (14:21 -0700)]
shmem: replace_page must flush_dcache and others

Commit bde05d1ccd51 ("shmem: replace page if mapping excludes its zone")
is not at all likely to break for anyone, but it was an earlier version
from before review feedback was incorporated.  Fix that up now.

* shmem_replace_page must flush_dcache_page after copy_highpage [akpm]
* Expand comment on why shmem_unuse_inode needs page_swapcount [akpm]
* Remove excess of VM_BUG_ONs from shmem_replace_page [wangcong]
* Check page_private matches swap before calling shmem_replace_page [hughd]
* shmem_replace_page allow for unexpected race in radix_tree lookup [hughd]

Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Stephane Marchesin <marcheu@chromium.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Dave Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Rob Clark <rob.clark@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agox86, efi stub: Add .reloc section back into image
Jordan Justen [Thu, 7 Jun 2012 16:05:21 +0000 (09:05 -0700)]
x86, efi stub: Add .reloc section back into image

Some UEFI firmware will not load a .efi with a .reloc section
with a size of 0.

Therefore, we create a .efi image with 4 main areas and 3 sections.
1. PE/COFF file header
2. .setup section (covers all setup code following the first sector)
3. .reloc section (contains 1 dummy reloc entry, created in build.c)
4. .text section (covers the remaining kernel image)

To make room for the new .setup section data, the header
bugger_off_msg had to be shortened.

Reported-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Link: http://lkml.kernel.org/r/1339085121-12760-1-git-send-email-jordan.l.justen@intel.com
Tested-by: Lee G Rosenbaum <lee.g.rosenbaum@intel.com>
Tested-by: Henrik Rydberg <rydberg@euromail.se>
Cc: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
11 years agoMerge tag 'parisc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6
Linus Torvalds [Thu, 7 Jun 2012 16:06:54 +0000 (09:06 -0700)]
Merge tag 'parisc-fixes' of git://git./linux/kernel/git/jejb/parisc-2.6

Pull PARISC fixes from James Bottomley:
 "This is a set of three bug fixes for minor build breakages that got
  introduced just before 3.5-rc1 was released."

* tag 'parisc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6:
  [PARISC] fix code to find libgcc
  [PARISC] fix compile break in use of lib/strncopy_from_user.c
  [PARISC] fix missing TAINT_WARN problem

11 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile
Linus Torvalds [Thu, 7 Jun 2012 16:06:13 +0000 (09:06 -0700)]
Merge git://git./linux/kernel/git/cmetcalf/linux-tile

Pull tile fixes from Chris Metcalf:
 "These two minor bug fixes fix build failures from some changes that
  were merged in during the 3.5 merge window."

* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  tile: add #include to unbreak build after generic init_task conversion
  tile: remove cpu_idle_on_new_stack

11 years agoUBI: correct ubi_wl_flush locking
Artem Bityutskiy [Thu, 7 Jun 2012 12:15:30 +0000 (15:15 +0300)]
UBI: correct ubi_wl_flush locking

Commit "62f38455 UBI: modify ubi_wl_flush function to clear work queue for a lnum"
takes the 'work_sem' semaphore in write mode for the entire loop, which is not
very good because it will block other workers for potentially long time. We do
not need to have it in write mode - read mode is enough, and we do not need to
hole it over the entire loop. So this patch turns changes the locking: takes
'work_sem' in read mode and pushes it down to the loop.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
11 years agoUBIFS: fix debugfs-less systems support
Artem Bityutskiy [Wed, 6 Jun 2012 13:03:10 +0000 (16:03 +0300)]
UBIFS: fix debugfs-less systems support

Commit "f70b7e5 UBIFS: remove Kconfig debugging option" broke UBIFS and it
refuses to initialize if debugfs (CONFIG_DEBUG_FS) is disabled. I incorrectly
assumed that debugfs files creation function will return success if debugfs
is disabled, but they actually return -ENODEV. This patch fixes the issue.

Reported-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Tested-by: Paul Parsons <lost.distance@yahoo.com>
11 years agoUBI: fix debugfs-less systems support
Artem Bityutskiy [Wed, 6 Jun 2012 12:22:41 +0000 (15:22 +0300)]
UBI: fix debugfs-less systems support

Commit "aa44d1d UBI: remove Kconfig debugging option" broke UBI and it
refuses to initialize if debugfs (CONFIG_DEBUG_FS) is disabled. I incorrectly
assumed that debugfs files creation function will return success if debugfs
is disabled, but they actually return -ENODEV. This patch fixes the issue.

Reported-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Tested-by: Paul Parsons <lost.distance@yahoo.com>
11 years agodrm/i915: pch_irq_handler -> {ibx, cpt}_irq_handler
Adam Jackson [Wed, 6 Jun 2012 19:45:44 +0000 (15:45 -0400)]
drm/i915: pch_irq_handler -> {ibx, cpt}_irq_handler

Cougar/Panther Point redefine the bits in SDEIIR pretty completely.
This function is just debugging, but if we're debugging we probably want
to be told accurate things instead of lies.

I'm told Lynx Point changes this yet more, but I have no idea how...

Note from Eugeni's review:

"For the record and for future enabling efforts, for LPT, bits 28-31
and 1-14 are gone since CPT/PPT (e.g., those must be zero). And there
is the bit 15 as a new addition, but we are not using it yet and
probably won't be using in foreseeable future."

Signed-off-by: Adam Jackson <ajax@redhat.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=35103
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
11 years agoMerge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck...
Linus Torvalds [Wed, 6 Jun 2012 18:56:45 +0000 (11:56 -0700)]
Merge tag 'hwmon-for-linus' of git://git./linux/kernel/git/groeck/linux-staging

Pull hwmon fix from Guenter Roeck:
 "Update e-mail address in MAINTAINERS"

* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  MAINTAINERS: Update my e-mail address

11 years agoMerge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux
Linus Torvalds [Wed, 6 Jun 2012 17:47:15 +0000 (10:47 -0700)]
Merge branch 'release' of git://git./linux/kernel/git/lenb/linux

Pull ACPI and Power Management changes from Len Brown.

This does an evil merge to fix up what I think is a mismerge by Len to
the gma500 driver, and restore it to the mainline state.

In that driver, both branches had commented out the call to
acpi_video_register(), and Len resolved the merge to that commented-out
version.

However, in mainline, further changes by Alan (commit d839ede47a56:
"gma500: opregion and ACPI" to be exact) had re-enabled the ACPI video
registration, so the current state of the driver seems to want it.

Alan is apparently still feeling the effects of partying with the Queen,
so he didn't reply to my query, but I'll do the evil merge anyway.

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
  ACPI: fix acpi_bus.h build warnings when ACPI is not enabled
  drivers: acpi: Fix dependency for ACPI_HOTPLUG_CPU
  tools/power turbostat: fix IVB support
  tools/power turbostat: fix un-intended affinity of forked program
  ACPI video: use after input_unregister_device()
  gma500: don't register the ACPI video bus
  acpi_video: Intel video is not always i915
  acpi_video: fix leaking PCI references
  ACPI: Ignore invalid _PSS entries, but use valid ones
  ACPI battery: only refresh the sysfs files when pertinent information changes

11 years agoMerge tag 'rdma-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
Linus Torvalds [Wed, 6 Jun 2012 17:45:21 +0000 (10:45 -0700)]
Merge tag 'rdma-fixes' of git://git./linux/kernel/git/roland/infiniband

Pull InfiniBand/RDMA fixes from Roland Dreier:
 "All in hardware drivers:
   - Fix crash in cxgb4
   - Fixes to new ocrdma driver
   - Regression fixes for mlx4"

* tag 'rdma-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
  IB/mlx4: Fix max_wqe capacity reported from query device
  mlx4_core: Fix setting VL_cap in mlx4_SET_PORT wrapper flow
  IB/mlx4: Fix EQ deallocation in legacy mode
  RDMA/cxgb4: Fix crash when peer address is 0.0.0.0
  RDMA/ocrdma: Remove unnecessary version.h includes
  RDMA/ocrdma: Fix signaled event for SRQ_LIMIT_REACHED
  RDMA/ocrdma: Correct queue free count math

11 years agoMerge branches 'cxgb4', 'mlx4' and 'ocrdma' into for-linus
Roland Dreier [Wed, 6 Jun 2012 17:08:11 +0000 (10:08 -0700)]
Merge branches 'cxgb4', 'mlx4' and 'ocrdma' into for-linus

11 years agoIB/mlx4: Fix max_wqe capacity reported from query device
Sagi Grimberg [Thu, 24 May 2012 13:08:08 +0000 (16:08 +0300)]
IB/mlx4: Fix max_wqe capacity reported from query device

1. Limit the max number of WQEs per QP reported when querying the
   device, so that ib_create_qp() will not fail for a QP size that the
   device claimed to support due to additional headroom WQEs being
   allocated.

2. Limit qp resources accepted for ib_create_qp() to the limits
   reported in ib_query_device().  In kernel space, make sure that the
   limits returned to the caller following qp creation also lie within
   the reported device limits. For userspace, report as before, and do
   adjustment in libmlx4 (so as not to break ABI).

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Sagi Grimberg <sagig@mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
11 years agomlx4_core: Fix setting VL_cap in mlx4_SET_PORT wrapper flow
Jack Morgenstein [Thu, 24 May 2012 13:08:09 +0000 (16:08 +0300)]
mlx4_core: Fix setting VL_cap in mlx4_SET_PORT wrapper flow

Commit 096335b3f983 ("mlx4_core: Allow dynamic MTU configuration for
IB ports") modifies the port VL setting.  This exposes a bug in
mlx4_common_set_port(), where the VL cap value passed in (inside the
command mailbox) is incorrectly zeroed-out:

mlx4_SET_PORT modifies the VL_cap field (byte 3 of the mailbox).
Since the SET_PORT command is paravirtualized on the master as well as
on the slaves, mlx4_SET_PORT_wrapper() is invoked on the master.  This
calls mlx4_common_set_port() where mailbox byte 3 gets overwritten by
code which should only set a single bit in that byte (for the reset
qkey counter flag) -- but instead overwrites the entire byte.

The result is that when running in SR-IOV mode, the VL_cap will be set
to zero -- fix this.

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
11 years agoMerge tag 'md-3.5-fixes' of git://neil.brown.name/md
Linus Torvalds [Wed, 6 Jun 2012 16:49:28 +0000 (09:49 -0700)]
Merge tag 'md-3.5-fixes' of git://neil.brown.name/md

Pull two md fixes from NeilBrown:
 "One sparse-warning fix, one bugfix for 3.4-stable"

* tag 'md-3.5-fixes' of git://neil.brown.name/md:
  md: raid1/raid10: fix problem with merge_bvec_fn
  lib/raid6: fix sparse warnings in recovery functions

11 years agoMerge tag 'iommu-fixes-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Wed, 6 Jun 2012 16:47:57 +0000 (09:47 -0700)]
Merge tag 'iommu-fixes-3.5-rc1' of git://git./linux/kernel/git/joro/iommu

Pull IOMMU fixes from Joerg Roedel:
 "Two patches are in here which fix AMD IOMMU specific issues.  One
  patch fixes a long-standing warning on resume because the
  amd_iommu_resume function enabled interrupts.  The other patch fixes a
  deadlock in an error-path of the page-fault request handling code of
  the IOMMU driver.

* tag 'iommu-fixes-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/amd: Fix deadlock in ppr-handling error path
  iommu/amd: Cache pdev pointer to root-bridge

11 years agotile: add #include to unbreak build after generic init_task conversion
Chris Metcalf [Wed, 6 Jun 2012 15:23:19 +0000 (11:23 -0400)]
tile: add #include to unbreak build after generic init_task conversion

Some code was moved from init_task.c to setup.c but the appropriate
header needed to be moved as well.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
11 years agotile: remove cpu_idle_on_new_stack
Chris Metcalf [Wed, 6 Jun 2012 15:21:44 +0000 (11:21 -0400)]
tile: remove cpu_idle_on_new_stack

This routine isn't used unless CONFIG_HOMECACHE is enabled, which
isn't even available as a public configuration option yet.
Since it no longer links correctly in 3.4, just remove it for now.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
11 years agoperf/x86: Don't assume there can be only 4 PEBS events
Andi Kleen [Wed, 6 Jun 2012 00:56:48 +0000 (17:56 -0700)]
perf/x86: Don't assume there can be only 4 PEBS events

On Sandy Bridge in non HT mode there are 8 counters available.
Since every counter can write a PEBS record assuming there are
4 max is incorrect. Use the reported counter number -- with an
upper limit for a static array -- instead.

Also I made the warning messages a bit more informational.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338944211-28275-2-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agoperf/x86: Use rdpmc() rather than rdmsr() when possible in the kernel
Vince Weaver [Thu, 1 Mar 2012 22:28:14 +0000 (17:28 -0500)]
perf/x86: Use rdpmc() rather than rdmsr() when possible in the kernel

The rdpmc instruction is faster than the equivelant rdmsr call,
so use it when possible in the kernel.

The perfctr kernel patches did this, after extensive testing showed
rdpmc to always be faster (One can look in etc/costs in the perfctr-2.6
package to see a historical list of the overhead).

I have done some tests on a 3.2 kernel, the kernel module I used
was included in the first posting of this patch:

                   rdmsr           rdpmc
 Core2 T9900:      203.9 cycles     30.9 cycles
 AMD fam0fh:        56.2 cycles      9.8 cycles
 Atom 6/28/2:      129.7 cycles     50.6 cycles

The speedup of using rdpmc is large.

[ It's probably possible (and desirable) to do this without
  requiring a new field in the hw_perf_event structure, but
  the fixed events make this tricky. ]

Signed-off-by: Vince Weaver <vweaver1@eecs.utk.edu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/alpine.DEB.2.00.1203011724030.26934@cl320.eecs.utk.edu
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agox86: Add rdpmcl()
Andi Kleen [Wed, 6 Jun 2012 00:56:50 +0000 (17:56 -0700)]
x86: Add rdpmcl()

Add a version of rdpmc() that directly reads into a u64

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338944211-28275-4-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agoperf/x86: Fix wrmsrl() debug wrapper
Peter Zijlstra [Mon, 14 May 2012 13:25:34 +0000 (15:25 +0200)]
perf/x86: Fix wrmsrl() debug wrapper

Move the wrmslr() debug wrapper to the common header now that all the
include games are gone. Also clean it up a bit to avoid multiple
evaluation of the argument.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-l4gkfnivwv4yi5mqxjlovymx@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agoMerge branch 'perf/urgent' into perf/core
Ingo Molnar [Wed, 6 Jun 2012 15:00:37 +0000 (17:00 +0200)]
Merge branch 'perf/urgent' into perf/core

Eliminate a conflict in a patch I am going to apply.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agoperf/x86: Update SNB PEBS constraints
Peter Zijlstra [Tue, 5 Jun 2012 08:26:43 +0000 (10:26 +0200)]
perf/x86: Update SNB PEBS constraints

Afaict there's no need to (incompletely) iterate the
MEM_UOPS_RETIRED.* umask state.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1338884803.28282.153.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agoperf/x86: Enable/Add IvyBridge hardware support
Peter Zijlstra [Tue, 5 Jun 2012 08:26:43 +0000 (10:26 +0200)]
perf/x86: Enable/Add IvyBridge hardware support

Implement rudimentary IVB perf support. The SDM states its identical
to SNB with exception of the exact event tables, but a quick look
suggests they're similar enough.

Also mark SNB-EP as broken for now.

Requested-and-tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338884803.28282.153.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agoperf/x86: Implement cycles:p for SNB/IVB
Peter Zijlstra [Tue, 5 Jun 2012 08:26:43 +0000 (10:26 +0200)]
perf/x86: Implement cycles:p for SNB/IVB

Now that there's finally a chip with working PEBS (IvyBridge), we can
enable the hardware and implement cycles:p for SNB/IVB.

Cc: Stephane Eranian <eranian@google.com>
Requested-and-tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338884803.28282.153.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agoperf/x86: Fix Intel shared extra MSR allocation
Peter Zijlstra [Tue, 5 Jun 2012 13:30:31 +0000 (15:30 +0200)]
perf/x86: Fix Intel shared extra MSR allocation

Zheng Yan reported that event group validation can wreck event state
when Intel extra_reg allocation changes event state.

Validation shouldn't change any persistent state. Cloning events in
validate_{event,group}() isn't really pretty either, so add a few
special cases to avoid modifying the event state.

The code is restructured to minimize the special case impact.

Reported-by: Zheng Yan <zheng.z.yan@linux.intel.com>
Acked-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338903031.28282.175.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Kill uprobes_srcu/uprobe_srcu_id
Oleg Nesterov [Tue, 29 May 2012 19:30:08 +0000 (21:30 +0200)]
uprobes: Kill uprobes_srcu/uprobe_srcu_id

Kill the no longer needed uprobes_srcu/uprobe_srcu_id code.

It doesn't really work anyway. synchronize_srcu() can only
synchronize with the code "inside" the
srcu_read_lock/srcu_read_unlock section, while
uprobe_pre_sstep_notifier() does srcu_read_lock() _after_ we
already hit the breakpoint.

I guess this probably works "in practice". synchronize_srcu() is
slow and it implies synchronize_sched(), and the probed task
enters the non- preemptible section at the start of exception
handler. Still this is not right at least in theory, and
task->uprobe_srcu_id blows task_struct.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120529193008.GG8057@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Teach handle_swbp() to rely on "is_swbp" rather than uprobes_srcu
Oleg Nesterov [Tue, 29 May 2012 19:29:47 +0000 (21:29 +0200)]
uprobes: Teach handle_swbp() to rely on "is_swbp" rather than uprobes_srcu

Currently handle_swbp() assumes that it can't race with
unregister, so it roughly does:

if (find_uprobe(vaddr))
process_uprobe();
else
send_sig(SIGTRAP);

This relies on the not-really-working uprobes_srcu code we are
going to remove, see the next patch.

With this patch we rely on the result of
is_swbp_at_addr(bp_vaddr) if find_uprobe() fails.

If is_swbp == 1, then we hit the normal int3, we should send
SIGTRAP.

If is_swbp == 0, we raced with uprobe_unregister(), we simply
restart this insn again.

The "difficult" case is is_swbp == -EFAULT, when we can't read
this memory. In this case I think we should restart too, and
this is more correct compared to the current code which sends
SIGTRAP.

Ignoring ENOMEM/etc from get_user_pages(), this can only happen
if another thread unmaps this memory before find_active_uprobe()
takes mmap_sem. It would be better to pretend it was unmapped
before this insn was executed, restart, and get SIGSEGV.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120529192947.GF8057@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Change register_for_each_vma() to take mm->mmap_sem for writing
Oleg Nesterov [Tue, 29 May 2012 19:29:28 +0000 (21:29 +0200)]
uprobes: Change register_for_each_vma() to take mm->mmap_sem for writing

Change register_for_each_vma() to take mm->mmap_sem for writing.
This is a bit unfortunate but hopefully not too bad, this is the
slow path anyway.

This is needed to ensure that find_active_uprobe() can not race
with uprobe_register() which adds the new bp at the same
bp_vaddr, after find_uprobe() fails and before
is_swbp_at_addr_fast() checks the memory.

IOW, this is needed to ensure that if find_active_uprobe()
returns NULL but is_swbp == true, we can safely assume that it
was the "normal" int3 and we should send SIGTRAP.

There is another reason for this change. We are going to replace
uprobes_state->count with MMF_ flags set by register/unregister
and cleared by find_active_uprobe(), and set/clear shouldn't
race with each other.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120529192928.GE8057@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Teach find_active_uprobe() to provide the "is_swbp" info
Oleg Nesterov [Tue, 29 May 2012 19:29:14 +0000 (21:29 +0200)]
uprobes: Teach find_active_uprobe() to provide the "is_swbp" info

A separate patch to simplify the review, and for the
documentation.

The patch adds another "int *is_swbp" argument to
find_active_uprobe(), so far its only caller doesn't use this
info.

With this patch find_active_uprobe() additionally does:

- if find_vma() + ->vm_start check fails, *is_swbp = -EFAULT

- otherwise, if valid_vma() + find_uprobe() fails, it holds
  the result of is_swbp_at_addr(), can be negative too. The
  latter is only possible if we raced with another thread
  which did munmap/etc after we hit this bp.

IOW. If find_active_uprobe(&is_swbp) returns NULL, the caller
can look at is_swbp to figure out whether the current insn is bp
or not, or detect the race with another thread if it is
negative.

Note: I think that performance-wise this change is fine. This
adds is_swbp_at_addr(), but only if we raced with
uprobe_unregister() or if we hit the "normal" int3 but this mm
has uprobes as well. And even in this case the slow
read_opcode() path is very unlikely, this insn recently
triggered do_int3(), __copy_from_user_inatomic() shouldn't fail
in the likely case.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120529192914.GD8057@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
11 years agouprobes: Introduce find_active_uprobe() helper
Oleg Nesterov [Tue, 29 May 2012 19:28:57 +0000 (21:28 +0200)]
uprobes: Introduce find_active_uprobe() helper

No functional changes. Move the "find uprobe" code from
handle_swbp() to the new helper, find_active_uprobe().

Note: with or without this change, the find-active-uprobe logic
is not exactly right. We can race with another thread which
unmaps the memory with the valid uprobe before we take
mm->mmap_sem. We can't find this uprobe simply because
find_vma() fails. In this case we wrongly assume that this trap
was not caused by uprobe and send the erroneous SIGTRAP. See the
next changes.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120529192857.GC8057@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>