The list macros use LIST_POISON1 and LIST_POISON2 as undereferencable
pointers in order to trap erronous use of freed list_heads. Unfortunately
userspace can arrange for those pointers to actually be dereferencable,
potentially turning an oops to an expolit.
To avoid this allow architectures (currently x86_64 only) to override
the default values for these pointers with truly-undereferencable values.
This is easy on x86_64 as the virtual address space is large and contains
areas that cannot be mapped.
Other 64-bit architectures will likely find similar unmapped ranges.
[ingo: switch to 0xdead000000000000 as the unmapped area]
[ingo: add comments, cleanup]
[jaswinder: eliminate sparse warnings]
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch series adds generic support for creating and extracting
LZO-compressed kernel images, as well as support for using such images on
the x86 and ARM architectures, and support for creating and using
LZO-compressed initrd and initramfs images.
Russell King said:
: Testing on a Cortex A9 model:
: - lzo decompressor is 65% of the time gzip takes to decompress a kernel
: - lzo kernel is 9% larger than a gzip kernel
:
: which I'm happy to say confirms your figures when comparing the two.
:
: However, when comparing your new gzip code to the old gzip code:
: - new is 99% of the size of the old code
: - new takes 42% of the time to decompress than the old code
:
: What this means is that for a proper comparison, the results get even better:
: - lzo is 7.5% larger than the old gzip'd kernel image
: - lzo takes 28% of the time that the old gzip code took
:
: So the expense seems definitely worth the effort. The only reason I
: can think of ever using gzip would be if you needed the additional
: compression (eg, because you have limited flash to store the image.)
:
: I would argue that the default for ARM should therefore be LZO.
This patch:
The lzo compressor is worse than gzip at compression, but faster at
extraction. Here are some figures for an ARM board I'm working on:
Uncompressed size: 3.24Mo
gzip 1.61Mo 0.72s
lzo 1.75Mo 0.48s
So for a compression ratio that is still relatively close to gzip, it's
much faster to extract, at least in that case.
This part contains:
- Makefile routine to support lzo compression
- Fixes to the existing lzo compressor so that it can be used in
compressed kernels
- wrapper around the existing lzo1x_decompress, as it only extracts one
block at a time, while we need to extract a whole file here
- config dialog for kernel compression
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Tested-by: Wu Zhangjin <wuzhangjin@gmail.com>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Russell King <rmk@arm.linux.org.uk>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
kgdb: Fix kernel-doc format error in kgdb.h
blackfin,kgdb: Do not put PC in gdb_regs into retx.
blackfin,kgdb,probe_kernel: Cleanup probe_kernel_read/write
maccess,probe_kernel: Allow arch specific override probe_kernel_(read|write)
linux-next-20081022//include/linux/kgdb.h:308): duplicate section name 'Description'
and fix typos in that file's kernel-doc comments.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Some archs such as blackfin, would like to have an arch specific
probe_kernel_read() and probe_kernel_write() implementation which can
fall back to the generic implementation if no special operations are
needed.
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
When working with FDPIC, there are many shared mappings of read-only
code regions between applications (the C library, applet packages like
busybox, etc.), but the current do_mmap_pgoff() function will issue an
icache flush whenever a VMA is added to an MM instead of only doing it
when the map is initially created.
The flush can instead be done when a region is first mmapped PROT_EXEC.
Note that we may not rely on the first mapping of a region being
executable - it's possible for it to be PROT_READ only, so we have to
remember whether we've flushed the region or not, and then flush the
entire region when a bit of it is made executable.
However, this also affects the brk area. That will no longer be
executable. We can mprotect() it to PROT_EXEC on MPU-mode kernels, but
for NOMMU mode kernels, when it increases the brk allocation, making
sys_brk() flush the extra from the icache should suffice. The brk area
probably isn't used by NOMMU programs since the brk area can only use up
the leavings from the stack allocation, where the stack allocation is
larger than requested.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It turns out that some PCI devices require extra delays when changing
power state from D3 to D0 (and the other way around). Although this
is against the PCI specification, we can handle it quite easily by
allowing drivers to define arbitrary D3 delays for devices known to
require extra time for switching power states.
Introduce additional field d3_delay in struct pci_dev and use it to
store the value of the device's D0->D3 delay, in miliseconds. Make
the PCI PM core code use the per-device d3_delay unless
pci_pm_d3_delay is greater (in which case the latter is used).
[This also allows the driver to specify d3_delay shorter than the
10 ms required by the PCI standard if the device is known to be able
to handle that.]
Make the sky2 driver set d3_delay to 150 for devices handled by it.
Fixes http://bugzilla.kernel.org/show_bug.cgi?id=14730 which is a
listed regression from 2.6.30.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We want to be sure that compiler fetches the limit variable only
once, so add helpers for fetching current and maximal resource
limits which do that.
Add them to sched.h (instead of resource.h) due to circular dependency
sched.h->resource.h->task_struct
Alternative would be to create a separate res_access.h or similar.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: James Morris <jmorris@namei.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
It is an internal function. Move it inside __KERNEL__ ifdef, along
with task_struct declaration.
Then we get:
--- /usr/include/linux/resource.h 2009-09-14 15:09:29.000000000 +0200
+++ usr/include/linux/resource.h 2010-01-04 11:30:54.000000000 +0100
@@ -3,8 +3,6 @@
#include <linux/time.h>
-struct task_struct;
-
/*
* Resource control/accounting header file for linux
*/
@@ -70,6 +68,5 @@
*/
#include <asm/resource.h>
-int getrusage(struct task_struct *p, int who, struct rusage *ru);
#endif
***********
include/linux/Kbuild is untouched, since unifdef is run even on
headers-y nowadays.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
When we relax the reiserfs lock to avoid creating unwanted
dependencies against others locks while grabbing these,
we want to ensure it has not been taken recursively, otherwise
the lock won't be really relaxed. Only its depth will be decreased.
The unwanted dependency would then actually happen.
To prevent from that, add a reiserfs_lock_check_recursive() call
in the places that need it.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Alexander Beregalov <a.beregalov@gmail.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Ingo Molnar <mingo@elte.hu>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
firewire, ieee1394: update Kconfig help
firewire, ieee1394: update MAINTAINERS entries
firewire: ohci: always use packet-per-buffer mode for isochronous reception
firewire: cdev: fix another memory leak in an error path
firewire: fix use of multiple AV/C devices, allow multiple FCP listeners
Comments from Stefan:
Distributors who still ship the old stack (ieee1394, ohci1394,
raw1394, sbp2, eth1394 and more) should now switch to the new one
(firewire-core, firewire-ohci, firewire-sbp2, firewire-net). In the
first iteration, those distributors might want to ship the old stack
also (but blacklisted) as a fallback for their users if unforeseen
problems with the newer replacement drivers are encountered.
The older FireWire stack contains several known problems which are
not going to be fixed; instead, those issues are addressed by the new
stack. An incomplete list of these issues is kept in bugzilla:
http://bugzilla.kernel.org/show_bug.cgi?id=10046
We have a guide on migration from the older to the newer stack:
http://ieee1394.wiki.kernel.org/index.php/Juju_Migration
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing: Fix sign fields in ftrace_define_fields_##call()
tracing/syscalls: Fix typo in SYSCALL_DEFINE0
tracing/kprobe: Show sign of fields in trace_kprobe format files
ksym_tracer: Remove trace_stat
ksym_tracer: Fix race when incrementing count
ksym_tracer: Fix to allow writing newline to ksym_trace_filter
ksym_tracer: Fix to make the tracer work
tracing: Kconfig spelling fixes and cleanups
tracing: Fix setting tracer specific options
Documentation: Update ftrace-design.txt
Documentation: Update tracepoint-analysis.txt
Documentation: Update mmiotrace.txt
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6:
ACPI: introduce kernel parameter acpi_sleep=sci_force_enable
ACPI: WMI: Survive BIOS with duplicate GUIDs
dell-wmi - fix condition to abort driver loading
wmi: check find_guid() return value to prevent oops
dell-wmi, hp-wmi, msi-wmi: check wmi_get_event_data() return value
ACPI: hp-wmi, msi-wmi: clarify that wmi_install_notify_handler() returns an acpi_status
dell-wmi: sys_init_module: 'dell_wmi'->init suspiciously returned 21, it should
ACPI video: correct error-handling code
ACPI video: no warning message if "acpi_backlight=vendor" is used
ACPI: fix ACPI=n allmodconfig build
thinkpad-acpi: improve Kconfig help text
thinkpad-acpi: update volume subdriver documentation
thinkpad-acpi: make volume subdriver optional
thinkpad-acpi: don't fail to load the entire module due to ALSA problems
thinkpad-acpi: don't take the first ALSA slot by default
Introduce kernel parameter acpi_sleep=sci_force_enable
some laptop requires SCI_EN being set directly on resume,
or else they hung somewhere in the resume code path.
We already have a blacklist for these laptops but we still need
this option, especially when debugging some suspend/resume problems,
in case there are systems that need this workaround and are not yet
in the blacklist.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: Patch up how we claim metadata blocks for quota purposes
ext4: Ensure zeroout blocks have no dirty metadata
ext4: return correct wbc.nr_to_write in ext4_da_writepages
ext4: Update documentation to correct the inode_readahead_blks option name
jbd2: don't use __GFP_NOFAIL in journal_init_common()
ext4: flush delalloc blocks when space is low
fs-writeback: Add helper function to start writeback if idle
ext4: Eliminate potential double free on error path
ext4: fix unsigned long long printk warning in super.c
ext4, jbd2: Add barriers for file systems with exernal journals
ext4: replace BUG() with return -EIO in ext4_ext_get_blocks
ext4: add module aliases for ext2 and ext3
ext4: Don't ask about supporting ext2/3 in ext4 if ext4 is not configured
ext4: remove unused #include <linux/version.h>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI/cardbus: Add a fixup hook and fix powerpc
PCI: change PCI nomenclature in drivers/pci/ (non-comment changes)
PCI: change PCI nomenclature in drivers/pci/ (comment changes)
PCI: fix section mismatch on update_res()
PCI: add Intel 82599 Virtual Function specific reset method
PCI: add Intel USB specific reset method
PCI: support device-specific reset methods
PCI: Handle case when no pci device can provide cache line size hint
PCI/PM: Propagate wake-up enable for PCIe devices too
vgaarbiter: fix a typo in the vgaarbiter Documentation
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
block: blk_rq_err_sectors cleanup
block: Honor the gfp_mask for alloc_page() in blkdev_issue_discard()
block: Fix incorrect alignment offset reporting and update documentation
cfq-iosched: don't regard requests with long distance as close
aoe: switch to the new bio_flush_dcache_pages() interface
drivers/block/mg_disk.c: use resource_size()
drivers/block/DAC960.c: use DAC960_V2_Controller
block: Fix topology stacking for data and discard alignment
drbd: remove unused #include <linux/version.h>
drbd: remove duplicated #include
drbd: Fix test of unsigned in _drbd_fault_random()
drbd: Constify struct file_operations
cfq-iosched: Remove prio_change logic for workload selection
cfq-iosched: Get rid of nr_groups
cfq-iosched: Remove the check for same cfq group from allow_merge
drbd: fix test of unsigned in _drbd_fault_random()
block: remove Documentation/block/as-iosched.txt
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (74 commits)
Revert "b43: Enforce DMA descriptor memory constraints"
iwmc3200wifi: fix array out-of-boundary access
wl1251: timeout one too soon in wl1251_boot_run_firmware()
mac80211: fix propagation of failed hardware reconfigurations
mac80211: fix race with suspend and dynamic_ps_disable_work
ath9k: fix missed error codes in the tx status check
ath9k: wake hardware during AMPDU TX actions
ath9k: wake hardware for interface IBSS/AP/Mesh removal
ath9k: fix suspend by waking device prior to stop
cfg80211: fix error path in cfg80211_wext_siwscan
wl1271_cmd.c: cleanup char => u8
iwlwifi: Storage class should be before const qualifier
ath9k: Storage class should be before const qualifier
cfg80211: fix race between deauth and assoc response
wireless: remove remaining qual code
rt2x00: Add USB ID for Linksys WUSB 600N rev 2.
ath5k: fix SWI calibration interrupt storm
mac80211: fix ibss join with fixed-bssid
libertas: Remove carrier signaling from the scan code
orinoco: fix GFP_KERNEL in orinoco_set_key with interrupts disabled
...
