Commit Graph

5762 Commits

Author SHA1 Message Date
Jeremy Fitzhardinge
777cba16aa x86: unify pgd_page
Impact: cleanup

Unify and demacro pgd_page.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-06 12:31:48 -08:00
Jeremy Fitzhardinge
f476961cb1 x86: unify pud_page
Impact: cleanup

Unify and demacro pud_page.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-06 12:31:48 -08:00
Jeremy Fitzhardinge
aca159dbb1 x86: include pgtable_SIZE.h earlier
We'll need the definitions sooner.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-06 12:31:48 -08:00
Jeremy Fitzhardinge
6fff47e3ac x86: unify pud_page_vaddr
Impact: cleanup

Unify and demacro pud_page_vaddr.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-06 12:31:48 -08:00
Jeremy Fitzhardinge
c5f040b12b x86: unify pgd_page_vaddr
Impact: cleanup

Unify and demacro pgd_page_vaddr.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-06 12:31:48 -08:00
Jeremy Fitzhardinge
4fea801ac9 x86: unify pmd_none
Impact: cleanup

Unify and demacro pmd_none.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-06 12:31:48 -08:00
Jeremy Fitzhardinge
649e8ef60f x86: unify pmd_present
Impact: cleanup

Unify and demacro pmd_present.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-06 12:31:47 -08:00
Jeremy Fitzhardinge
9f38d7e85e x86: unify pgd_present
Impact: cleanup

Unify and demacro pgd_present.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-06 12:31:07 -08:00
Jeremy Fitzhardinge
5ba7c91341 x86: unify pud_present
Impact: cleanup

Unify and demacro pud_present.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-06 12:31:07 -08:00
Jeremy Fitzhardinge
7c683851d9 x86: unify pte_present
Impact: cleanup

Unify and demacro pte_present.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-06 12:28:37 -08:00
Jeremy Fitzhardinge
8de01da35e x86: unify pte_same
Impact: cleanup

Unify and demacro pte_same.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-06 12:26:08 -08:00
Jeremy Fitzhardinge
a034a010f4 x86: unify pte_none
Impact: cleanup

Unify and demacro pte_none.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-06 12:26:08 -08:00
Linus Torvalds
45c82b5a77 Merge branch 'header-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'header-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (90 commits)
  headers_check fix: x86, swab.h
  headers_check fix: x86, sigcontext32.h
  headers_check fix: x86, sigcontext.h
  headers_check fix: x86, ptrace-abi.h
  headers_check fix: x86, mtrr.h
  headers_check fix: x86, mce.h
  headers_check fix: x86, kvm.h
  headers_check fix: x86, e820.h
  headers_check fix: linux/rtnetlink.h
  headers_check fix: linux/nubus.h
  headers_check fix: video/uvesafb.h
  headers_check fix: video/sisfb.h
  headers_check fix: sound/hdsp.h
  headers_check fix: mtd/inftl-user.h
  headers_check fix: linux/virtio_net.h
  headers_check fix: linux/virtio_console.h
  headers_check fix: linux/virtio_blk.h
  headers_check fix: linux/videodev.h
  headers_check fix: linux/video_encoder.h
  headers_check fix: linux/video_decoder.h
  ...
2009-01-31 15:56:23 -08:00
Linus Torvalds
f6490438fc Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, ds, bts: cleanup/fix DS configuration
  ring-buffer: reset timestamps when ring buffer is reset
  trace: set max latency variable to zero on default
  trace: stop all recording to ring buffer on ftrace_dump
  trace: print ftrace_dump at KERN_EMERG log level
  ring_buffer: reset write when reserve buffer fail
  tracing/function-graph-tracer: fix a regression while suspend to disk
  ring-buffer: fix alignment problem
2009-01-31 15:53:30 -08:00
Linus Torvalds
e81cfd214f 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 setup: fix asm constraints in vesa_store_edid
  xen: make sysfs files behave as their names suggest
  x86: tone down mtrr_trim_uncached_memory() warning
  x86: correct the CPUID pattern for MSR_IA32_MISC_ENABLE availability
2009-01-31 15:52:46 -08:00
Andreas Schwab
7fc49f1981 x86 setup: fix asm constraints in vesa_store_edid
Impact: fix potential miscompile (currently believed non-manifest)

As the comment explains, the VBE DDC call can clobber any register.
Tell the compiler about that fact.

Signed-off-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-30 23:55:25 +01:00
Jaswinder Singh Rajput
7cff3608d2 headers_check fix: x86, swab.h
fix the following 'make headers_check' warnings:

  usr/include/asm/swab.h:4: include of <linux/types.h> is preferred over <asm/types.h>
  usr/include/asm/swab.h:7: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-01-31 00:19:32 +05:30
Jaswinder Singh Rajput
2de548faa7 headers_check fix: x86, sigcontext32.h
fix the following 'make headers_check' warning:

  usr/include/asm/sigcontext32.h:20: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-01-31 00:18:58 +05:30
Jaswinder Singh Rajput
e59afe6a21 headers_check fix: x86, sigcontext.h
fix the following 'make headers_check' warnings:

  usr/include/asm/sigcontext.h:5: include of <linux/types.h> is preferred over <asm/types.h>
  usr/include/asm/sigcontext.h:24: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-01-31 00:18:30 +05:30
Jaswinder Singh Rajput
420ab35eef headers_check fix: x86, ptrace-abi.h
fix the following 'make headers_check' warnings:

  usr/include/asm/ptrace-abi.h:86: include of <linux/types.h> is preferred over <asm/types.h>
  usr/include/asm/ptrace-abi.h:93: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-01-31 00:18:03 +05:30
Jaswinder Singh Rajput
d122072cc0 headers_check fix: x86, mtrr.h
fix the following 'make headers_check' warning:

  usr/include/asm/mtrr.h:61: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-01-31 00:17:39 +05:30
Jaswinder Singh Rajput
999b697b9d headers_check fix: x86, mce.h
fix the following 'make headers_check' warnings:

  usr/include/asm/mce.h:7: include of <linux/types.h> is preferred over <asm/types.h>
  usr/include/asm/mce.h:29: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-01-31 00:17:13 +05:30
Jaswinder Singh Rajput
cef3767852 headers_check fix: x86, kvm.h
fix the following 'make headers_check' warnings:

  usr/include/asm/kvm.h:9: include of <linux/types.h> is preferred over <asm/types.h>
  usr/include/asm/kvm.h:16: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-01-31 00:16:44 +05:30
Jaswinder Singh Rajput
999721ca6d headers_check fix: x86, e820.h
fix the following 'make headers_check' warning:

  usr/include/asm/e820.h:44: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-01-31 00:16:22 +05:30
Randy Dunlap
5872fb94f8 Documentation: move DMA-mapping.txt to Doc/PCI/
Move DMA-mapping.txt to Documentation/PCI/.

DMA-mapping.txt was supposed to be moved from Documentation/ to
Documentation/PCI/.  The 00-INDEX files in those two directories
were updated, along with a few other text files, but the file
itself somehow escaped being moved, so move it and update more
text files and source files with its new location.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
cc:	Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-29 18:19:29 -08:00
Atsushi SAKAI
72410af921 lguest: typos fix
3 points

lguest_asm.S => i386_head.S
LHCALL_BREAK => LHREQ_BREAK
perferred    => preferred

Signed-off-by: Atsushi SAKAI <sakaia@jp.fujitsu.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-30 11:34:10 +10:30
Ingo Molnar
bf3647c44b x86: tone down mtrr_trim_uncached_memory() warning
kerneloops.org is reporting a lot of these warnings that come due to
vmware not setting up any MTRRs for emulated CPUs:

| Reported 709 times (14696 total reports)
| BIOS bug (often in VMWare) where the MTRR's are set up incorrectly
| or not at all
|
| This warning was last seen in version 2.6.29-rc2-git1, and first
| seen in 2.6.24.
|
| More info:
|   http://www.kerneloops.org/searchweek.php?search=mtrr_trim_uncached_memory

Keep a one-liner KERN_INFO about it - so that we have so notice if empty
MTRRs are caused by native hardware/BIOS weirdness.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-29 11:45:35 +01:00
Linus Torvalds
cfb901bf84 Merge branch 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6
* 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6:
  i2c: Warn on deprecated binding model use
  eeprom: More consistent symbol names
  eeprom: Move 93cx6 eeprom driver to /drivers/misc/eeprom
  spi: Move at25 (for SPI eeproms) to /drivers/misc/eeprom
  i2c: Move old eeprom driver to /drivers/misc/eeprom
  i2c: Move at24 to drivers/misc/eeprom
  i2c: Quilt tree has moved
  i2c: Delete many unused adapter IDs
  i2c: Delete 10 unused driver IDs
2009-01-26 15:11:41 -08:00
Linus Torvalds
2034563ca3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fixes
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fixes:
  kbuild: fix kbuild.txt typos
  kbuild: print usage with no arguments in scripts/config
  Revert "kbuild: strip generated symbols from *.ko"
2009-01-26 15:10:37 -08:00
Jean Delvare
dd7f8dbe2b eeprom: More consistent symbol names
Now that all EEPROM drivers live in the same place, let's harmonize
their symbol names.

Also fix eeprom's dependencies, it definitely needs sysfs, and is no
longer experimental after many years in the kernel tree.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
2009-01-26 21:19:57 +01:00
Linus Torvalds
3386c05bdb Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  debugobjects: add and use INIT_WORK_ON_STACK
  rcu: remove duplicate CONFIG_RCU_CPU_STALL_DETECTOR
  relay: fix lock imbalance in relay_late_setup_files
  oprofile: fix uninitialized use of struct op_entry
  rcu: move Kconfig menu
  softlock: fix false panic which can occur if softlockup_thresh is reduced
  rcu: add __cpuinit to rcu_init_percpu_data()
2009-01-26 09:47:56 -08:00
Linus Torvalds
1e70c7f7a9 Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  hrtimers: fix inconsistent lock state on resume in hres_timers_resume
  time-sched.c: tick_nohz_update_jiffies should be static
  locking, hpet: annotate false positive warning
  kernel/fork.c: unused variable 'ret'
  itimers: remove the per-cpu-ish-ness
2009-01-26 09:47:43 -08:00
Linus Torvalds
810ee58de2 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: (29 commits)
  xen: unitialised return value in xenbus_write_transaction
  x86: fix section mismatch warning
  x86: unmask CPUID levels on Intel CPUs, fix
  x86: work around PAGE_KERNEL_WC not getting WC in iomap_atomic_prot_pfn.
  x86: use standard PIT frequency
  xen: handle highmem pages correctly when shrinking a domain
  x86, mm: fix pte_free()
  xen: actually release memory when shrinking domain
  x86: unmask CPUID levels on Intel CPUs
  x86: add MSR_IA32_MISC_ENABLE bits to <asm/msr-index.h>
  x86: fix PTE corruption issue while mapping RAM using /dev/mem
  x86: mtrr fix debug boot parameter
  x86: fix page attribute corruption with cpa()
  Revert "x86: signal: change type of paramter for sys_rt_sigreturn()"
  x86: use early clobbers in usercopy*.c
  x86: remove kernel_physical_mapping_init() from init section
  fix: crash: IP: __bitmap_intersects+0x48/0x73
  cpufreq: use work_on_cpu in acpi-cpufreq.c for drv_read and drv_write
  work_on_cpu: Use our own workqueue.
  work_on_cpu: don't try to get_online_cpus() in work_on_cpu.
  ...
2009-01-26 09:47:28 -08:00
H. Peter Anvin
30a0fb947a x86: correct the CPUID pattern for MSR_IA32_MISC_ENABLE availability
Impact: re-enable CPUID unmasking on affected processors

As far as I am capable of discerning from the documentation,
MSR_IA32_MISC_ENABLE should be available for all family 0xf CPUs, as
well as family 6 for model >= 0xd (newer Pentium M).

The documentation on this isn't ideal, so we need to be on the lookout
for errors, still.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-01-26 09:40:58 -08:00
Rakib Mullick
659d2618b3 x86: fix section mismatch warning
Here function vmi_activate calls a init function activate_vmi , which
causes the following section mismatch warnings:

  LD      arch/x86/kernel/built-in.o
WARNING: arch/x86/kernel/built-in.o(.text+0x13ba9): Section mismatch
in reference from the function vmi_activate() to the function
.init.text:vmi_time_init()
The function vmi_activate() references
the function __init vmi_time_init().
This is often because vmi_activate lacks a __init
annotation or the annotation of vmi_time_init is wrong.

WARNING: arch/x86/kernel/built-in.o(.text+0x13bd1): Section mismatch
in reference from the function vmi_activate() to the function
.devinit.text:vmi_time_bsp_init()
The function vmi_activate() references
the function __devinit vmi_time_bsp_init().
This is often because vmi_activate lacks a __devinit
annotation or the annotation of vmi_time_bsp_init is wrong.

WARNING: arch/x86/kernel/built-in.o(.text+0x13bdb): Section mismatch
in reference from the function vmi_activate() to the function
.devinit.text:vmi_time_ap_init()
The function vmi_activate() references
the function __devinit vmi_time_ap_init().
This is often because vmi_activate lacks a __devinit
annotation or the annotation of vmi_time_ap_init is wrong.

Fix it by marking vmi_activate() as __init too.

Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-26 14:27:18 +01:00
Ingo Molnar
99fb4d349d x86: unmask CPUID levels on Intel CPUs, fix
Impact: fix boot hang on pre-model-15 Intel CPUs

rdmsrl_safe() does not work in very early bootup code yet, because we
dont have the pagefault handler installed yet so exception section
does not get parsed. rdmsr_safe() will just crash and hang the bootup.

So limit the MSR_IA32_MISC_ENABLE MSR read to those CPU types that
support it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-26 12:36:24 +01:00
Eric Anholt
ef5fa0ab24 x86: work around PAGE_KERNEL_WC not getting WC in iomap_atomic_prot_pfn.
In the absence of PAT, PAGE_KERNEL_WC ends up mapping to a memory type that
gets UC behavior even in the presence of a WC MTRR covering the area in
question.  By swapping to PAGE_KERNEL_UC_MINUS, we can get the actual
behavior the caller wanted (WC if you can manage it, UC otherwise).

This recovers the 40% performance improvement of using WC in the DRM
to upload vertex data.

Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-01-26 11:14:27 +01:00
Ingo Molnar
e1b4d11436 x86: use standard PIT frequency
the RDC and ELAN platforms use slighly different PIT clocks, resulting in
a timex.h hack that changes PIT_TICK_RATE during build time. But if a
tester enables any of these platform support .config options, the PIT
will be miscalibrated on standard PC platforms.

So use one frequency - in a subsequent patch we'll add a quirk to allow
x86 platforms to define different PIT frequencies.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-25 16:57:47 +01:00
Peter Zijlstra
42ef73fe13 x86, mm: fix pte_free()
On -rt we were seeing spurious bad page states like:

Bad page state in process 'firefox'
page:c1bc2380 flags:0x40000000 mapping:c1bc2390 mapcount:0 count:0
Trying to fix it up, but a reboot is needed
Backtrace:
Pid: 503, comm: firefox Not tainted 2.6.26.8-rt13 #3
[<c043d0f3>] ? printk+0x14/0x19
[<c0272d4e>] bad_page+0x4e/0x79
[<c0273831>] free_hot_cold_page+0x5b/0x1d3
[<c02739f6>] free_hot_page+0xf/0x11
[<c0273a18>] __free_pages+0x20/0x2b
[<c027d170>] __pte_alloc+0x87/0x91
[<c027d25e>] handle_mm_fault+0xe4/0x733
[<c043f680>] ? rt_mutex_down_read_trylock+0x57/0x63
[<c043f680>] ? rt_mutex_down_read_trylock+0x57/0x63
[<c0218875>] do_page_fault+0x36f/0x88a

This is the case where a concurrent fault already installed the PTE and
we get to free the newly allocated one.

This is due to pgtable_page_ctor() doing the spin_lock_init(&page->ptl)
which is overlaid with the {private, mapping} struct.

union {
    struct {
        unsigned long private;
        struct address_space *mapping;
    };
    spinlock_t ptl;
    struct kmem_cache *slab;
    struct page *first_page;
};

Normally the spinlock is small enough to not stomp on page->mapping, but
PREEMPT_RT=y has huge 'spin'locks.

But lockdep kernels should also be able to trigger this splat, as the
lock tracking code grows the spinlock to cover page->mapping.

The obvious fix is calling pgtable_page_dtor() like the regular pte free
path __pte_free_tlb() does.

It seems all architectures except x86 and nm10300 already do this, and
nm10300 doesn't seem to use pgtable_page_ctor(), which suggests it
doesn't do SMP or simply doesnt do MMU at all or something.

Signed-off-by: Peter Zijlstra <a.p.zijlsta@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
2009-01-23 18:42:06 +01:00
Markus Metzger
ba2607fe9c x86, ds, bts: cleanup/fix DS configuration
Cleanup the cpuid check for DS configuration.

This also fixes a Corei7 CPUID enumeration bug.

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-22 14:35:00 +01:00
Thomas Gleixner
336f6c322d debugobjects: add and use INIT_WORK_ON_STACK
Impact: Fix debugobjects warning

debugobject enabled kernels spit out a warning in hpet code due to a
workqueue which is initialized on stack.

Add INIT_WORK_ON_STACK() which calls init_timer_on_stack() and use it
in hpet.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-01-22 10:02:07 +01:00
H. Peter Anvin
066941bd4e x86: unmask CPUID levels on Intel CPUs
Impact: Fixes crashes with misconfigured BIOSes on XSAVE hardware

Avuton Olrich reported early boot crashes with v2.6.28 and
bisected it down to dc1e35c6e9
("x86, xsave: enable xsave/xrstor on cpus with xsave support").

If the CPUID limit bit in MSR_IA32_MISC_ENABLE is set, clear it to
make all CPUID information available.  This is required for some
features to work, in particular XSAVE.

Reported-and-bisected-by: Avuton Olrich <avuton@gmail.com>
Tested-by: Avuton Olrich <avuton@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-01-22 09:24:02 +01:00
H. Peter Anvin
bdf21a49ba x86: add MSR_IA32_MISC_ENABLE bits to <asm/msr-index.h>
Impact: None (new bit definitions currently unused)

Add bit definitions for the MSR_IA32_MISC_ENABLE MSRs to
<asm/msr-index.h>.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-01-21 15:13:53 -08:00
Suresh Siddha
9597134218 x86: fix PTE corruption issue while mapping RAM using /dev/mem
Beschorner Daniel reported:
> hwinfo problem since 2.6.28, showing this in the oops:
>	Corrupted page table at address 7fd04de3ec00

Also, PaX Team reported a regression with this commit:

>	commit 9542ada803
>	Author: Suresh Siddha <suresh.b.siddha@intel.com>
>	Date:   Wed Sep 24 08:53:33 2008 -0700
>
>	    x86: track memtype for RAM in page struct

This commit breaks mapping any RAM page through /dev/mem, as the
reserve_memtype() was not initializing the return attribute type and as such
corrupting the PTE entry that was setup with the return attribute type.

Because of this bug, application mapping this RAM page through /dev/mem
will die with "Corrupted page table at address xxxx" message in the kernel
log and also the kernel identity mapping which maps the underlying RAM
page gets converted to UC.

Fix this by initializing the return attribute type before calling
reserve_ram_pages_type()

Reported-by: PaX Team <pageexec@freemail.hu>
Reported-and-tested-by: Beschorner Daniel <Daniel.Beschorner@facton.com>
Tested-and-Acked-by: PaX Team <pageexec@freemail.hu>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-21 18:42:32 +01:00
Thomas Renninger
731f1872f4 x86: mtrr fix debug boot parameter
while looking at:

  http://bugzilla.kernel.org/show_bug.cgi?id=11541

I realized that the mtrr.show param cannot work, because
the code is processed much too early.

This patch:
 - Declares mtrr.show as early_param
 - Stays consistent with the previous param (which I doubt
   that it ever worked), so mtrr.show=1 would still work
 - Declares mtrr_show as initdata

Signed-off-by: Thomas Renninger <trenn@suse.de>
Acked-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-21 12:26:42 +01:00
Suresh Siddha
a1e46212a4 x86: fix page attribute corruption with cpa()
Impact: fix sporadic slowdowns and warning messages

This patch fixes a performance issue reported by Linus on his
Nehalem system. While Linus reverted the PAT patch (commit
58dab916df) which exposed the issue,
existing cpa() code can potentially still cause wrong(page attribute
corruption) behavior.

This patch also fixes the "WARNING: at arch/x86/mm/pageattr.c:560" that
various people reported.

In 64bit kernel, kernel identity mapping might have holes depending
on the available memory and how e820 reports the address range
covering the RAM, ACPI, PCI reserved regions. If there is a 2MB/1GB hole
in the address range that is not listed by e820 entries, kernel identity
mapping will have a corresponding hole in its 1-1 identity mapping.

If cpa() happens on the kernel identity mapping which falls into these holes,
existing code fails like this:

	__change_page_attr_set_clr()
		__change_page_attr()
			returns 0 because of if (!kpte). But doesn't
			set cpa->numpages and cpa->pfn.
		cpa_process_alias()
			uses uninitialized cpa->pfn (random value)
			which can potentially lead to changing the page
			attribute of kernel text/data, kernel identity
			mapping of RAM pages etc. oops!

This bug was easily exposed by another PAT patch which was doing
cpa() more often on kernel identity mapping holes (physical range between
max_low_pfn_mapped and 4GB), where in here it was setting the
cache disable attribute(PCD) for kernel identity mappings aswell.

Fix cpa() to handle the kernel identity mapping holes. Retain
the WARN() for cpa() calls to other not present address ranges
(kernel-text/data, ioremap() addresses)

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-21 12:24:54 +01:00
Ingo Molnar
552b8aa4d1 Revert "x86: signal: change type of paramter for sys_rt_sigreturn()"
This reverts commit 4217458daf.

Justin Madru bisected this commit, it was causing weird Firefox
crashes.

The reason is that GCC mis-optimizes (re-uses) the on-stack parameters of
the calling frame, which corrupts the syscall return pt_regs state and
thus corrupts user-space register state.

So we go back to the slightly less clean but more optimization-safe
method of getting to pt_regs. Also add a comment to explain this.

Resolves: http://bugzilla.kernel.org/show_bug.cgi?id=12505

Reported-and-bisected-by: Justin Madru <jdm64@gawab.com>
Tested-by: Justin Madru <jdm64@gawab.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-21 09:43:18 +01:00
Andi Kleen
e0a96129db x86: use early clobbers in usercopy*.c
Impact: fix rare (but currently harmless) miscompile with certain configs and gcc versions

Hugh Dickins noticed that strncpy_from_user() was miscompiled
in some circumstances with gcc 4.3.

Thanks to Hugh's excellent analysis it was easy to track down.

Hugh writes:

> Try building an x86_64 defconfig 2.6.29-rc1 kernel tree,
> except not quite defconfig, switch CONFIG_PREEMPT_NONE=y
> and CONFIG_PREEMPT_VOLUNTARY off (because it expands a
> might_fault() there, which hides the issue): using a
> gcc 4.3.2 (I've checked both openSUSE 11.1 and Fedora 10).
>
> It generates the following:
>
> 0000000000000000 <__strncpy_from_user>:
>    0:   48 89 d1                mov    %rdx,%rcx
>    3:   48 85 c9                test   %rcx,%rcx
>    6:   74 0e                   je     16 <__strncpy_from_user+0x16>
>    8:   ac                      lods   %ds:(%rsi),%al
>    9:   aa                      stos   %al,%es:(%rdi)
>    a:   84 c0                   test   %al,%al
>    c:   74 05                   je     13 <__strncpy_from_user+0x13>
>    e:   48 ff c9                dec    %rcx
>   11:   75 f5                   jne    8 <__strncpy_from_user+0x8>
>   13:   48 29 c9                sub    %rcx,%rcx
>   16:   48 89 c8                mov    %rcx,%rax
>   19:   c3                      retq
>
> Observe that "sub %rcx,%rcx; mov %rcx,%rax", whereas gcc 4.2.1
> (and many other configs) say "sub %rcx,%rdx; mov %rdx,%rax".
> Isn't it returning 0 when it ought to be returning strlen?

The asm constraints for the strncpy_from_user() result were missing an
early clobber, which tells gcc that the last output arguments
are written before all input arguments are read.

Also add more early clobbers in the rest of the file and fix 32-bit
usercopy.c in the same way.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
[ since this API is rarely used and no in-kernel user relies on a 'len'
  return value (they only rely on negative return values) this miscompile
  was never noticed in the field. But it's worth fixing it nevertheless. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-21 09:43:17 +01:00
Gary Hade
f5495506c3 x86: remove kernel_physical_mapping_init() from init section
Impact: fix crash with memory hotplug enabled

kernel_physical_mapping_init() is called during memory hotplug
so it does not belong in the init section.

If the kernel is built with CONFIG_DEBUG_SECTION_MISMATCH=y on
the make command line, arch/x86/mm/init_64.c is compiled with
the -fno-inline-functions-called-once gcc option defeating
inlining of kernel_physical_mapping_init() within init_memory_mapping().

When kernel_physical_mapping_init() is not inlined it is placed
in the .init.text section according to the __init in it's current
declaration.  A later call to kernel_physical_mapping_init() during
a memory hotplug operation encounters an int3 trap because the
.init.text section memory has been freed.

This patch eliminates the crash caused by the int3 trap by moving the
non-inlined kernel_physical_mapping_init() from .init.text to .meminit.text.

Signed-off-by: Gary Hade <garyhade@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-20 00:31:43 +01:00
Ingo Molnar
bfa318ad52 fix: crash: IP: __bitmap_intersects+0x48/0x73
-tip testing found this crash:

> [   35.258515] calling  acpi_cpufreq_init+0x0/0x127 @ 1
> [   35.264127] BUG: unable to handle kernel NULL pointer dereference at (null)
> [   35.267554] IP: [<ffffffff80478092>] __bitmap_intersects+0x48/0x73
> [   35.267554] PGD 0
> [   35.267554] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC

arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c is still broken: there's no
allocation of the variable mask, so we pass in an uninitialized cmd.mask
field to drv_read(), which then passes it to the scheduler which then
crashes ...

Switch it over to the much simpler constant-cpumask-pointers approach.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-20 00:17:01 +01:00