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  1. 11 Feb, 2009 3 commits
    • Ingo Molnar's avatar
      Merge branch 'master' of... · ffc04672
      Ingo Molnar authored 
      Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/perfcounters into perfcounters/core
      ffc04672
    • Ingo Molnar's avatar
      Merge commit 'v2.6.29-rc4' into perfcounters/core · 95fd4845
      Ingo Molnar authored 
      Conflicts:
	arch/x86/kernel/setup_percpu.c
	arch/x86/mm/fault.c
	drivers/acpi/processor_idle.c
	kernel/irq/handle.c
      95fd4845
    • Paul Mackerras's avatar
      perf_counters: allow users to count user, kernel and/or hypervisor events · 0475f9ea
      Paul Mackerras authored 
      Impact: new perf_counter feature

This extends the perf_counter_hw_event struct with bits that specify
that events in user, kernel and/or hypervisor mode should not be
counted (i.e. should be excluded), and adds code to program the PMU
mode selection bits accordingly on x86 and powerpc.

For software counters, we don't currently have the infrastructure to
distinguish which mode an event occurs in, so we currently fail the
counter initialization if the setting of the hw_event.exclude_* bits
would require us to distinguish.  Context switches and CPU migrations
are currently considered to occur in kernel mode.

On x86, this changes the previous policy that only root can count
kernel events.  Now non-root users can count kernel events or exclude
them.  Non-root users still can't use NMI events, though.  On x86 we
don't appear to have any way to control whether hypervisor events are
counted or not, so hw_event.exclude_hv is ignored.

On powerpc, the selection of whether to count events in user, kernel
and/or hypervisor mode is PMU-wide, not per-counter, so this adds a
check that the hw_event.exclude_* settings are the same as other events
on the PMU.  Counters being added to a group have to have the same
settings as the other hardware counters in the group.  Counters and
groups can only be enabled in hw_perf_group_sched_in or power_perf_enable
if they have the same settings as any other counters already on the
PMU.  If we are not running on a hypervisor, the exclude_hv setting
is ignored (by forcing it to 0) since we can't ever get any
hypervisor events.
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      0475f9ea
  3. 09 Feb, 2009 2 commits
    • Mike Galbraith's avatar
      perf_counters: account NMI interrupts · d278c484
      Mike Galbraith authored 
      I noticed that kerneltop interrupts were accounted as NMI, but not their
perf counter origin.

Account NMI performance counter interrupts.
Signed-off-by: default avatarMike Galbraith  <efault@gmx.de>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>

 arch/x86/kernel/cpu/perf_counter.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
      d278c484
    • Paul Mackerras's avatar
      perf_counters: make software counters work as per-cpu counters · 23a185ca
      Paul Mackerras authored 
      Impact: kernel crash fix

Yanmin Zhang reported that using a PERF_COUNT_TASK_CLOCK software
counter as a per-cpu counter would reliably crash the system, because
it calls __task_delta_exec with a null pointer.  The page fault,
context switch and cpu migration counters also won't function
correctly as per-cpu counters since they reference the current task.

This fixes the problem by redirecting the task_clock counter to the
cpu_clock counter when used as a per-cpu counter, and by implementing
per-cpu page fault, context switch and cpu migration counters.

Along the way, this:

- Initializes counter->ctx earlier, in perf_counter_alloc, so that
  sw_perf_counter_init can use it
- Adds code to kernel/sched.c to count task migrations into each
  cpu, in rq->nr_migrations_in
- Exports the per-cpu context switch and task migration counts
  via new functions added to kernel/sched.c
- Makes sure that if sw_perf_counter_init fails, we don't try to
  initialize the counter as a hardware counter.  Since the user has
  passed a negative, non-raw event type, they clearly don't intend
  for it to be interpreted as a hardware event.
Reported-by: default avatar"Zhang Yanmin" <yanmin_zhang@linux.intel.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      23a185ca
  5. 08 Feb, 2009 10 commits
  7. 07 Feb, 2009 18 commits
  9. 06 Feb, 2009 7 commits
    • David Howells's avatar
      CRED: Fix SUID exec regression · 0bf2f3ae
      David Howells authored 
      The patch:

	commit a6f76f23
	CRED: Make execve() take advantage of copy-on-write credentials

moved the place in which the 'safeness' of a SUID/SGID exec was performed to
before de_thread() was called.  This means that LSM_UNSAFE_SHARE is now
calculated incorrectly.  This flag is set if any of the usage counts for
fs_struct, files_struct and sighand_struct are greater than 1 at the time the
determination is made.  All of which are true for threads created by the
pthread library.

However, since we wish to make the security calculation before irrevocably
damaging the process so that we can return it an error code in the case where
we decide we want to reject the exec request on this basis, we have to make the
determination before calling de_thread().

So, instead, we count up the number of threads (CLONE_THREAD) that are sharing
our fs_struct (CLONE_FS), files_struct (CLONE_FILES) and sighand_structs
(CLONE_SIGHAND/CLONE_THREAD) with us.  These will be killed by de_thread() and
so can be discounted by check_unsafe_exec().

We do have to be careful because CLONE_THREAD does not imply FS or FILES.

We _assume_ that there will be no extra references to these structs held by the
threads we're going to kill.

This can be tested with the attached pair of programs.  Build the two programs
using the Makefile supplied, and run ./test1 as a non-root user.  If
successful, you should see something like:

	[dhowells@andromeda tmp]$ ./test1
	--TEST1--
	uid=4043, euid=4043 suid=4043
	exec ./test2
	--TEST2--
	uid=4043, euid=0 suid=0
	SUCCESS - Correct effective user ID

and if unsuccessful, something like:

	[dhowells@andromeda tmp]$ ./test1
	--TEST1--
	uid=4043, euid=4043 suid=4043
	exec ./test2
	--TEST2--
	uid=4043, euid=4043 suid=4043
	ERROR - Incorrect effective user ID!

The non-root user ID you see will depend on the user you run as.

[test1.c]
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>

static void *thread_func(void *arg)
{
	while (1) {}
}

int main(int argc, char **argv)
{
	pthread_t tid;
	uid_t uid, euid, suid;

	printf("--TEST1--\n");
	getresuid(&uid, &euid, &suid);
	printf("uid=%d, euid=%d suid=%d\n", uid, euid, suid);

	if (pthread_create(&tid, NULL, thread_func, NULL) < 0) {
		perror("pthread_create");
		exit(1);
	}

	printf("exec ./test2\n");
	execlp("./test2", "test2", NULL);
	perror("./test2");
	_exit(1);
}

[test2.c]
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc, char **argv)
{
	uid_t uid, euid, suid;

	getresuid(&uid, &euid, &suid);
	printf("--TEST2--\n");
	printf("uid=%d, euid=%d suid=%d\n", uid, euid, suid);

	if (euid != 0) {
		fprintf(stderr, "ERROR - Incorrect effective user ID!\n");
		exit(1);
	}
	printf("SUCCESS - Correct effective user ID\n");
	exit(0);
}

[Makefile]
CFLAGS = -D_GNU_SOURCE -Wall -Werror -Wunused
all: test1 test2

test1: test1.c
	gcc $(CFLAGS) -o test1 test1.c -lpthread

test2: test2.c
	gcc $(CFLAGS) -o test2 test2.c
	sudo chown root.root test2
	sudo chmod +s test2
Reported-by: default avatarDavid Smith <dsmith@redhat.com>
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Acked-by: default avatarDavid Smith <dsmith@redhat.com>
Signed-off-by: default avatarJames Morris <jmorris@namei.org>
      0bf2f3ae
    • Dave Kleikamp's avatar
      vfs: Don't call attach_nobh_buffers() with an empty list · d4cf109f
      Dave Kleikamp authored 
      This is a modification of a patch by Bill Pemberton <wfp5p@virginia.edu>

nobh_write_end() could call attach_nobh_buffers() with head == NULL.
This would result in a trap when attach_nobh_buffers() attempted to
access bh->b_this_page.

This can be illustrated by running the writev01 testcase from LTP on jfs.

This error was introduced by commit 5b41e74a "vfs: fix data leak in
nobh_write_end()".  That patch did not take into account that if
PageMappedToDisk() is true upon entry to nobh_write_begin(), then no
buffers will be allocated for the page.  In that case, we won't have to
worry about a failed write leaving unitialized data in the page.

Of course, head != NULL implies !page_has_buffers(page), so no need to
test both.
Signed-off-by: default avatarDave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Dmitri Monakhov <dmonakhov@openvz.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      d4cf109f
    • Linus Torvalds's avatar
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6 · 6cec5083
      Linus Torvalds authored 
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
  ALSA: hda - Add missing COEF initialization for ALC887
  ALSA: hda - Add missing initialization for ALC272
  sound: usb-audio: handle wMaxPacketSize for FIXED_ENDPOINT devices
  ALSA: hda - Fix misc workqueue issues
  ALSA: hda - Add quirk for FSC Amilo Xi2550
      6cec5083
    • Len Brown's avatar
      ACPI: disable ACPI cleanly when bad RSDP found · 9e3a9d1e
      Len Brown authored 
      When ACPI is disabled in the BIOS of this VIA C3 box,
it invalidates the RSDP, which Linux notices:

ACPI Error (tbxfroot-0218): A valid RSDP was not found [20080926]

Bug Linux neglected to disable ACPI at that stage,
and later scribbled on smp_found_config:

ACPI: No APIC-table, disabling MPS

But this box doesn't run well in legacy PIC mode,
it needed IOAPIC mode to perform correctly:

http://lkml.org/lkml/2009/2/5/39

So exit ACPI mode cleanly when we first detect
that it is hopeless.
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
      9e3a9d1e
    • Len Brown's avatar
      ACPI: delete CPU_IDLE=n code · 9fdd54f2
      Len Brown authored 
      CPU_IDLE=y has been default for ACPI=y since Nov-2007,
and has shipped in many distributions since then.

Here we delete the CPU_IDLE=n ACPI idle code, since
nobody should be using it, and we don't want to
maintain two versions.
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
      9fdd54f2
    • Linus Torvalds's avatar
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6 · 5e3bd4e4
      Linus Torvalds authored 
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  ieee1394: dv1394: move deprecation message from module init to file open
  firewire: core: Remove card from list of cards when enable fails
      5e3bd4e4
    • Uwe Kleine-König's avatar
      Add Sascha Hauer to .mailmap · bcee402e
      Uwe Kleine-König authored 
      This fixes the shortlog attribution e.g. for 106757b3Signed-off-by: default avatarUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: default avatarSascha Hauer <s.hauer@pengutronix.de>
Acked-by: default avatarWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      bcee402e
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