Commit Graph

8281 Commits

Author SHA1 Message Date
Linus Torvalds
a66a50054e Merge branch 'core-iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (59 commits)
  x86/gart: Do not select AGP for GART_IOMMU
  x86/amd-iommu: Initialize passthrough mode when requested
  x86/amd-iommu: Don't detach device from pt domain on driver unbind
  x86/amd-iommu: Make sure a device is assigned in passthrough mode
  x86/amd-iommu: Align locking between attach_device and detach_device
  x86/amd-iommu: Fix device table write order
  x86/amd-iommu: Add passthrough mode initialization functions
  x86/amd-iommu: Add core functions for pd allocation/freeing
  x86/dma: Mark iommu_pass_through as __read_mostly
  x86/amd-iommu: Change iommu_map_page to support multiple page sizes
  x86/amd-iommu: Support higher level PTEs in iommu_page_unmap
  x86/amd-iommu: Remove old page table handling macros
  x86/amd-iommu: Use 2-level page tables for dma_ops domains
  x86/amd-iommu: Remove bus_addr check in iommu_map_page
  x86/amd-iommu: Remove last usages of IOMMU_PTE_L0_INDEX
  x86/amd-iommu: Change alloc_pte to support 64 bit address space
  x86/amd-iommu: Introduce increase_address_space function
  x86/amd-iommu: Flush domains if address space size was increased
  x86/amd-iommu: Introduce set_dte_entry function
  x86/amd-iommu: Add a gneric version of amd_iommu_flush_all_devices
  ...
2009-09-11 13:16:37 -07:00
Linus Torvalds
989aa44a5f Merge branch 'core-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  debug lockups: Improve lockup detection, fix generic arch fallback
  debug lockups: Improve lockup detection
2009-09-11 13:15:55 -07:00
Linus Torvalds
332a339218 Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (102 commits)
  crypto: sha-s390 - Fix warnings in import function
  crypto: vmac - New hash algorithm for intel_txt support
  crypto: api - Do not displace newly registered algorithms
  crypto: ansi_cprng - Fix module initialization
  crypto: xcbc - Fix alignment calculation of xcbc_tfm_ctx
  crypto: fips - Depend on ansi_cprng
  crypto: blkcipher - Do not use eseqiv on stream ciphers
  crypto: ctr - Use chainiv on raw counter mode
  Revert crypto: fips - Select CPRNG
  crypto: rng - Fix typo
  crypto: talitos - add support for 36 bit addressing
  crypto: talitos - align locks on cache lines
  crypto: talitos - simplify hmac data size calculation
  crypto: mv_cesa - Add support for Orion5X crypto engine
  crypto: cryptd - Add support to access underlaying shash
  crypto: gcm - Use GHASH digest algorithm
  crypto: ghash - Add GHASH digest algorithm for GCM
  crypto: authenc - Convert to ahash
  crypto: api - Fix aligned ctx helper
  crypto: hmac - Prehash ipad/opad
  ...
2009-09-11 09:38:37 -07:00
Linus Torvalds
1b195b170d Merge branch 'kmemleak' of git://linux-arm.org/linux-2.6
* 'kmemleak' of git://linux-arm.org/linux-2.6:
  kmemleak: Improve the "Early log buffer exceeded" error message
  kmemleak: fix sparse warning for static declarations
  kmemleak: fix sparse warning over overshadowed flags
  kmemleak: move common painting code together
  kmemleak: add clear command support
  kmemleak: use bool for true/false questions
  kmemleak: Do no create the clean-up thread during kmemleak_disable()
  kmemleak: Scan all thread stacks
  kmemleak: Don't scan uninitialized memory when kmemcheck is enabled
  kmemleak: Ignore the aperture memory hole on x86_64
  kmemleak: Printing of the objects hex dump
  kmemleak: Do not report alloc_bootmem blocks as leaks
  kmemleak: Save the stack trace for early allocations
  kmemleak: Mark the early log buffer as __initdata
  kmemleak: Dump object information on request
  kmemleak: Allow rescheduling during an object scanning
2009-09-11 09:16:22 -07:00
James Morris
a3c8b97396 Merge branch 'next' into for-linus 2009-09-11 08:04:49 +10:00
Pekka Enberg
8e019366ba kmemleak: Don't scan uninitialized memory when kmemcheck is enabled
Ingo Molnar reported the following kmemcheck warning when running both
kmemleak and kmemcheck enabled:

  PM: Adding info for No Bus:vcsa7
  WARNING: kmemcheck: Caught 32-bit read from uninitialized memory
  (f6f6e1a4)
  d873f9f600000000c42ae4c1005c87f70000000070665f666978656400000000
   i i i i u u u u i i i i i i i i i i i i i i i i i i i i i u u u
           ^

  Pid: 3091, comm: kmemleak Not tainted (2.6.31-rc7-tip #1303) P4DC6
  EIP: 0060:[<c110301f>] EFLAGS: 00010006 CPU: 0
  EIP is at scan_block+0x3f/0xe0
  EAX: f40bd700 EBX: f40bd780 ECX: f16b46c0 EDX: 00000001
  ESI: f6f6e1a4 EDI: 00000000 EBP: f10f3f4c ESP: c2605fcc
   DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
  CR0: 8005003b CR2: e89a4844 CR3: 30ff1000 CR4: 000006f0
  DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
  DR6: ffff4ff0 DR7: 00000400
   [<c110313c>] scan_object+0x7c/0xf0
   [<c1103389>] kmemleak_scan+0x1d9/0x400
   [<c1103a3c>] kmemleak_scan_thread+0x4c/0xb0
   [<c10819d4>] kthread+0x74/0x80
   [<c10257db>] kernel_thread_helper+0x7/0x3c
   [<ffffffff>] 0xffffffff
  kmemleak: 515 new suspected memory leaks (see
  /sys/kernel/debug/kmemleak)
  kmemleak: 42 new suspected memory leaks (see /sys/kernel/debug/kmemleak)

The problem here is that kmemleak will scan partially initialized
objects that makes kmemcheck complain. Fix that up by skipping
uninitialized memory regions when kmemcheck is enabled.

Reported-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2009-09-04 16:05:55 +01:00
Ingo Molnar
695a461296 Merge branch 'amd-iommu/2.6.32' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/linux-2.6-iommu into core/iommu 2009-09-04 14:44:16 +02:00
Joerg Roedel
2b681fafcc Merge branch 'amd-iommu/pagetable' into amd-iommu/2.6.32
Conflicts:
	arch/x86/kernel/amd_iommu.c
2009-09-03 17:14:57 +02:00
Joerg Roedel
03362a05c5 Merge branch 'amd-iommu/passthrough' into amd-iommu/2.6.32
Conflicts:
	arch/x86/kernel/amd_iommu.c
	arch/x86/kernel/amd_iommu_init.c
2009-09-03 16:34:23 +02:00
Joerg Roedel
85da07c409 Merge branches 'gart/fixes', 'amd-iommu/fixes+cleanups' and 'amd-iommu/fault-handling' into amd-iommu/2.6.32 2009-09-03 16:32:00 +02:00
Pavel Vasilyev
6ac162d6c0 x86/gart: Do not select AGP for GART_IOMMU
There is no dependency from the gart code to the agp code.
And since a lot of systems today do not have agp anymore
remove this dependency from the kernel configuration.

Signed-off-by: Pavel Vasilyev <pavel@pavlinux.ru>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:20:55 +02:00
Joerg Roedel
4751a95134 x86/amd-iommu: Initialize passthrough mode when requested
This patch enables the passthrough mode for AMD IOMMU by
running the initialization function when iommu=pt is passed
on the kernel command line.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:15:46 +02:00
Joerg Roedel
a1ca331c8a x86/amd-iommu: Don't detach device from pt domain on driver unbind
This patch makes sure a device is not detached from the
passthrough domain when the device driver is unloaded or
does otherwise release the device.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:15:46 +02:00
Joerg Roedel
21129f786f x86/amd-iommu: Make sure a device is assigned in passthrough mode
When the IOMMU driver runs in passthrough mode it has to
make sure that every device not assigned to an IOMMU-API
domain must be put into the passthrough domain instead of
keeping it unassigned.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:15:45 +02:00
Joerg Roedel
eba6ac60ba x86/amd-iommu: Align locking between attach_device and detach_device
This patch makes the locking behavior between the functions
attach_device and __attach_device consistent with the
locking behavior between detach_device and __detach_device.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:15:44 +02:00
Joerg Roedel
aa879fff5d x86/amd-iommu: Fix device table write order
The V bit of the device table entry has to be set after the
rest of the entry is written to not confuse the hardware.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:15:43 +02:00
Joerg Roedel
0feae533dd x86/amd-iommu: Add passthrough mode initialization functions
When iommu=pt is passed on kernel command line the devices
should run untranslated. This requires the allocation of a
special domain for that purpose. This patch implements the
allocation and initialization path for iommu=pt.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:15:42 +02:00
Joerg Roedel
2650815fb0 x86/amd-iommu: Add core functions for pd allocation/freeing
This patch factors some code of protection domain allocation
into seperate functions. This way the logic can be used to
allocate the passthrough domain later. As a side effect this
patch fixes an unlikely domain id leakage bug.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:15:34 +02:00
Joerg Roedel
ac0101d396 x86/dma: Mark iommu_pass_through as __read_mostly
This variable is read most of the time. This patch marks it
as such. It also documents the meaning the this variable
while at it.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:13:46 +02:00
Joerg Roedel
abdc5eb3d6 x86/amd-iommu: Change iommu_map_page to support multiple page sizes
This patch adds a map_size parameter to the iommu_map_page
function which makes it generic enough to handle multiple
page sizes. This also requires a change to alloc_pte which
is also done in this patch.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:11:17 +02:00
Joerg Roedel
a6b256b413 x86/amd-iommu: Support higher level PTEs in iommu_page_unmap
This patch changes fetch_pte and iommu_page_unmap to support
different page sizes too.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:11:08 +02:00
Joerg Roedel
674d798a80 x86/amd-iommu: Remove old page table handling macros
These macros are not longer required. So remove them.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:03:49 +02:00
Joerg Roedel
8f7a017ce0 x86/amd-iommu: Use 2-level page tables for dma_ops domains
The driver now supports a dynamic number of levels for IO
page tables. This allows to reduce the number of levels for
dma_ops domains by one because a dma_ops domain has usually
an address space size between 128MB and 4G.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:03:49 +02:00
Joerg Roedel
bad1cac28a x86/amd-iommu: Remove bus_addr check in iommu_map_page
The driver now supports full 64 bit device address spaces.
So this check is not longer required.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:03:48 +02:00
Joerg Roedel
8c8c143cdc x86/amd-iommu: Remove last usages of IOMMU_PTE_L0_INDEX
This change allows to remove these old macros later.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:03:47 +02:00
Joerg Roedel
8bc3e12742 x86/amd-iommu: Change alloc_pte to support 64 bit address space
This patch changes the alloc_pte function to be able to map
pages into the whole 64 bit address space supported by AMD
IOMMU hardware from the old limit of 2**39 bytes.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:03:46 +02:00
Joerg Roedel
50020fb632 x86/amd-iommu: Introduce increase_address_space function
This function will be used to increase the address space
size of a protection domain.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:03:46 +02:00
Joerg Roedel
04bfdd8406 x86/amd-iommu: Flush domains if address space size was increased
Thist patch introduces the update_domain function which
propagates the larger address space of a protection domain
to the device table and flushes all relevant DTEs and the
domain TLB.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:03:45 +02:00
Joerg Roedel
407d733e30 x86/amd-iommu: Introduce set_dte_entry function
This function factors out some logic of attach_device to a
seperate function. This new function will be used to update
device table entries when necessary.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:03:44 +02:00
Joerg Roedel
6a0dbcbe4e x86/amd-iommu: Add a gneric version of amd_iommu_flush_all_devices
This patch adds a generic variant of
amd_iommu_flush_all_devices function which flushes only the
DTEs for a given protection domain.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:03:43 +02:00
Joerg Roedel
a6d41a4027 x86/amd-iommu: Use fetch_pte in amd_iommu_iova_to_phys
Don't reimplement the page table walker in this function.
Use the generic one.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:03:42 +02:00
Joerg Roedel
38a76eeeaf x86/amd-iommu: Use fetch_pte in iommu_unmap_page
Instead of reimplementing existing logic use fetch_pte to
walk the page table in iommu_unmap_page.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:03:41 +02:00
Joerg Roedel
9355a08186 x86/amd-iommu: Make fetch_pte aware of dynamic mapping levels
This patch changes the fetch_pte function in the AMD IOMMU
driver to support dynamic mapping levels.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 16:03:34 +02:00
Joerg Roedel
6a1eddd2f9 x86/amd-iommu: Reset command buffer if wait loop fails
Instead of a panic on an comletion wait loop failure, try to
recover from that event from resetting the command buffer.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 15:56:19 +02:00
Joerg Roedel
b26e81b871 x86/amd-iommu: Panic if IOMMU command buffer reset fails
To prevent the driver from doing recursive command buffer
resets, just panic when that recursion happens.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 15:55:35 +02:00
Joerg Roedel
a345b23b79 x86/amd-iommu: Reset command buffer on ILLEGAL_COMMAND_ERROR
On an ILLEGAL_COMMAND_ERROR the IOMMU stops executing
further commands. This patch changes the code to handle this
case better by resetting the command buffer in the IOMMU.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 15:55:34 +02:00
Joerg Roedel
93f1cc67cf x86/amd-iommu: Add reset function for command buffers
This patch factors parts of the command buffer
initialization code into a seperate function which can be
used to reset the command buffer later.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 15:55:34 +02:00
Joerg Roedel
d586d7852c x86/amd-iommu: Add function to flush all DTEs on one IOMMU
This function flushes all DTE entries on one IOMMU for all
devices behind this IOMMU. This is required for command
buffer resetting later.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 15:55:23 +02:00
Joerg Roedel
e0faf54ee8 x86/amd-iommu: fix broken check in amd_iommu_flush_all_devices
The amd_iommu_pd_table is indexed by protection domain
number and not by device id. So this check is broken and
must be removed.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 15:49:56 +02:00
Joerg Roedel
ae908c22aa x86/amd-iommu: Remove redundant 'IOMMU' string
The 'IOMMU: ' prefix is not necessary because the
DUMP_printk macro already prints its own prefix.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 15:49:56 +02:00
Joerg Roedel
4c6f40d4e0 x86/amd-iommu: replace "AMD IOMMU" by "AMD-Vi"
This patch replaces the "AMD IOMMU" printk strings with the
official name for the hardware: "AMD-Vi".

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 15:49:56 +02:00
Joerg Roedel
f2430bd104 x86/amd-iommu: Remove some merge helper code
This patch removes some left-overs which where put into the code to
simplify merging code which also depends on changes in other trees.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 15:49:55 +02:00
Joerg Roedel
e394d72aa8 x86/amd-iommu: Introduce function for iommu-local domain flush
This patch introduces a function to flush all domain tlbs
for on one given IOMMU. This is required later to reset the
command buffer on one IOMMU.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 15:41:34 +02:00
Joerg Roedel
945b4ac44e x86/amd-iommu: Dump illegal command on ILLEGAL_COMMAND_ERROR
This patch adds code to dump the command which caused an
ILLEGAL_COMMAND_ERROR raised by the IOMMU hardware.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 14:28:04 +02:00
Joerg Roedel
e3e59876e8 x86/amd-iommu: Dump fault entry on DTE error
This patch adds code to dump the content of the device table
entry which caused an ILLEGAL_DEV_TABLE_ENTRY error from the
IOMMU hardware.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-09-03 14:17:08 +02:00
David Howells
ee18d64c1f KEYS: Add a keyctl to install a process's session keyring on its parent [try #6]
Add a keyctl to install a process's session keyring onto its parent.  This
replaces the parent's session keyring.  Because the COW credential code does
not permit one process to change another process's credentials directly, the
change is deferred until userspace next starts executing again.  Normally this
will be after a wait*() syscall.

To support this, three new security hooks have been provided:
cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in
the blank security creds and key_session_to_parent() - which asks the LSM if
the process may replace its parent's session keyring.

The replacement may only happen if the process has the same ownership details
as its parent, and the process has LINK permission on the session keyring, and
the session keyring is owned by the process, and the LSM permits it.

Note that this requires alteration to each architecture's notify_resume path.
This has been done for all arches barring blackfin, m68k* and xtensa, all of
which need assembly alteration to support TIF_NOTIFY_RESUME.  This allows the
replacement to be performed at the point the parent process resumes userspace
execution.

This allows the userspace AFS pioctl emulation to fully emulate newpag() and
the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to
alter the parent process's PAG membership.  However, since kAFS doesn't use
PAGs per se, but rather dumps the keys into the session keyring, the session
keyring of the parent must be replaced if, for example, VIOCSETTOK is passed
the newpag flag.

This can be tested with the following program:

	#include <stdio.h>
	#include <stdlib.h>
	#include <keyutils.h>

	#define KEYCTL_SESSION_TO_PARENT	18

	#define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0)

	int main(int argc, char **argv)
	{
		key_serial_t keyring, key;
		long ret;

		keyring = keyctl_join_session_keyring(argv[1]);
		OSERROR(keyring, "keyctl_join_session_keyring");

		key = add_key("user", "a", "b", 1, keyring);
		OSERROR(key, "add_key");

		ret = keyctl(KEYCTL_SESSION_TO_PARENT);
		OSERROR(ret, "KEYCTL_SESSION_TO_PARENT");

		return 0;
	}

Compiled and linked with -lkeyutils, you should see something like:

	[dhowells@andromeda ~]$ keyctl show
	Session Keyring
	       -3 --alswrv   4043  4043  keyring: _ses
	355907932 --alswrv   4043    -1   \_ keyring: _uid.4043
	[dhowells@andromeda ~]$ /tmp/newpag
	[dhowells@andromeda ~]$ keyctl show
	Session Keyring
	       -3 --alswrv   4043  4043  keyring: _ses
	1055658746 --alswrv   4043  4043   \_ user: a
	[dhowells@andromeda ~]$ /tmp/newpag hello
	[dhowells@andromeda ~]$ keyctl show
	Session Keyring
	       -3 --alswrv   4043  4043  keyring: hello
	340417692 --alswrv   4043  4043   \_ user: a

Where the test program creates a new session keyring, sticks a user key named
'a' into it and then installs it on its parent.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-09-02 21:29:22 +10:00
Catalin Marinas
acde31dc46 kmemleak: Ignore the aperture memory hole on x86_64
This block is allocated with alloc_bootmem() and scanned by kmemleak but
the kernel direct mapping may no longer exist. This patch tells kmemleak
to ignore this memory hole. The dma32_bootmem_ptr in
dma32_reserve_bootmem() is also ignored.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
2009-09-01 11:12:32 +01:00
Yinghai Lu
295594e9cf x86: Fix vSMP boot crash
2.6.31-rc7 does not boot on vSMP systems:

[    8.501108] CPU31: Thermal monitoring enabled (TM1)
[    8.501127] CPU 31 MCA banks SHD:2 SHD:3 SHD:5 SHD:6 SHD:8
[    8.650254] CPU31: Intel(R) Xeon(R) CPU           E5540  @ 2.53GHz stepping 04
[    8.710324] Brought up 32 CPUs
[    8.713916] Total of 32 processors activated (162314.96 BogoMIPS).
[    8.721489] ERROR: parent span is not a superset of domain->span
[    8.727686] ERROR: domain->groups does not contain CPU0
[    8.733091] ERROR: groups don't span domain->span
[    8.737975] ERROR: domain->cpu_power not set
[    8.742416]

Ravikiran Thirumalai bisected it to:

| commit 2759c3287d
| x86: don't call read_apic_id if !cpu_has_apic

The problem is that on vSMP systems the CPUID derived
initial-APICIDs are overlapping - so we need to fall
back on hard_smp_processor_id() which reads the local
APIC.

Both come from the hardware (influenced by firmware
though) so it's a tough call which one to trust.

Doing the quirk expresses the vSMP property properly
and also does not affect other systems, so we go for
this solution instead of a revert.

Reported-and-Tested-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shai Fultheim <shai@scalex86.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <4A944D3C.5030100@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-26 10:13:17 +02:00
H. Peter Anvin
7adb4df410 x86, xen: Initialize cx to suppress warning
Initialize cx before calling xen_cpuid(), in order to suppress the
"may be used uninitialized in this function" warning.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
2009-08-25 21:10:32 -07:00
Jeremy Fitzhardinge
d560bc6157 x86, xen: Suppress WP test on Xen
Xen always runs on CPUs which properly support WP enforcement in
privileged mode, so there's no need to test for it.

This also works around a crash reported by Arnd Hannemann, though I
think its just a band-aid for that case.

Reported-by: Arnd Hannemann <hannemann@nets.rwth-aachen.de>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-25 21:10:32 -07:00