Russell King [Tue, 19 Oct 2004 17:11:22 +0000 (18:11 +0100)]
[SERIAL] Keep trying to register our console device.
Some serial drivers receive their serial port device information via
the device model. This unfortunately means that the selected port
may not be available when the console subsystem initialises, so we
must keep trying to register the console after each port is added.
Russell King [Tue, 19 Oct 2004 16:50:24 +0000 (17:50 +0100)]
[SERIAL] Add new port registration/unregistration functions.
serial8250_register_port()/serial8250_unregister_port() has the
capability of registering ports with their struct device nodes,
which allows sysfs to indicate which tty devices belong to which
hardware devices.
We also add a serial8250 platform device driver in an initial
attempt at PM for ISA ports. However, I'm leaving out the
platform device for the time being since adding that would cause
potential oops issues.
Russell King [Tue, 19 Oct 2004 16:22:21 +0000 (17:22 +0100)]
[SERIAL] Make port autoprobing set up->capabilities.
Convert port autoprobing to set up->capabilities as it discovers
various capabilities of the port. Warn when the detected
capabilities do not match those in the uart_config table.
Russell King [Tue, 19 Oct 2004 16:00:01 +0000 (17:00 +0100)]
[SERIAL] Clean up handling of LSR in receive function.
It's pointless accessing the LSR value via a pointer all the time -
it prevents the compiler optimising it. Also, ensure that we
recognise a break sent during a kernel printk correctly.
I've been informed that /proc/profile livelocks some systems in the timer
interrupt, usually at boot. The following patch attempts to amortize the
atomic operations done on the profile buffer to address this stability
concern. This patch has nothing to do with performance; kernels using
periodic timer interrupts are under realtime constraints to complete
whatever work they perform within timer interrupts before the next timer
interrupt arrives lest they livelock, performing no work whatsoever apart
from servicing timer interrupts. The latency of the cacheline bounce for
prof_buffer contributes to the time spent in the timer interrupt, hence it
must be amortized when remote access latencies or deviations from fair
exclusive cacheline acquisition may cause cacheline bounces to take longer
than the interval between timer ticks.
What this patch does is to create a pair of per-cpu open-addressed
hashtables indexed by profile buffer slot holding values representing the
number of pending profile buffer hits for the profile buffer slot. When
this hashtable overflows, one iterates over the hashtable accounting each
of the pairs of profile buffer slots and hit counts to the global profile
buffer. Zero is a legitimate profile buffer slot, so zero hit counts
represent unused hashtable entries. The hashtable is furthermore protected
from flush IPI's by interrupt disablement.
In order to flush the pending profile hits for read_profile(), this patch
flips betweeen the pairs of per-cpu profile buffer by signalling all cpus
to flip via IPI at the time of read_profile(), followed by doing all the
work to flush the profile hits from the older per-cpu buffers in the
context of the caller of read_profile(), with exclusion provided by a
semaphore ensuring that only one caller of profile_flip_buffers() may
execute at a time, and using interrupt disablement to prevent buffer flip
IPI's from altering the hashtables or flip state while an update is in
progress. The flip state is per-cpu so that remote cpus need only disable
interrupts locally for synchronization, which is both simple and
busywait-free for remote cpus. The flip states all change in tandem when
some cpu requests the hashtables be flipped, and the requester waits for
the completion of smp_call_function() for notification that all cpus have
finished flipping between their hashtables. The IPI handler merely toggles
the flip state (which is an array index) between 0 and 1.
This is expected to be a much stronger amortization than merely reducing
the frequency of profile buffer access by a factor of the size of the
hashtable because numerous hits may be held for each of its entries. This
reduces what was before the patch a number of atomic increments equal to
what after the patch becomes the sum of the hits held for each entry in the
hashtable, to a number of atomic_add()'s equal to the number of entries in
the per_cpu hashtable. This is nondeterministic, but as the profile hits
tend to be concentrated in a very small number of profile buffer slots
during any given timing interval, is likely to represent a very large
number of atomic increments. This amortization of atomic increments does
not depend on the hash function, only the sharp peakedness of the
distribution of profile buffer hits.
This algorithm has two advantages over full-size per-cpu profile buffers.
The first is that the space footprint is much smaller. Per-cpu profile
buffers would increase the space requirements by a factor of
num_online_cpus(), where this algorithm only requires one page per cpu.
The second is that reading the profile state is much faster, because the
state that must be traversed is exactly the above space consumers, and the
relative reduction in size concomitantly reduces the time required for a
read operation.
I also took the liberty of adding some commentary to the comments at the
beginning of the file reflecting the major work done on profile.c in recent
months and describing what the file implements.
The reporters of this issue have verified that this resolves their timer
interrupt livelock on 512x Altixen. In my own testing on 4x logical
x86-64, this patch saw a rate of about 18 flushes per minute under load, or
about one flush every 3 seconds, for about 38.4 atomic accesses to the
profile buffer per second per cpu in one of the algorithm's worst cases,
about 3.84% of the number of atomic profile buffer accesses per second per
cpu as a normal kernel would commit. This represents a twenty-six-fold
increase in the scalability on SMP systems with 4KB PAGE_SIZE, i.e. with a
4KB PAGE_SIZE, the number of atomic profile buffer accesses per second per
cpu is reduced by a factor of 26, thereby increasing the number of cpus a
system must have before it would experience a timer interrupt livelock by a
factor of 26, with the proviso that cacheline bounces must take the same
amount of time to service. This increase in the scalability of the kernel
is expected to be much larger for ia64, which has a large PAGE_SIZE,
because the distribution of profile buffer hits is so sharply peaked that
doubling the hashtable size will much more than double the amortization
factor. In fact, only 19 flushes were observed on a 64x Altix over an
approximately 10 minute AIM7 run, and 1 flush on a 512x Altix over the
course of an entire AIM7 run, for truly vast effective amortization
factors.
A prior version of this patch, which did not include the node-local
hashtable allocation and bounded collision chains has been successfully
tested on 64x and 512x ia64 vs 2.6.9-rc2, 8x ia64 vs. 2.6.9-rc2-mm1, 4x
x86-64 vs. 2.6.9-rc2-mm1, and 6x sparc64 vs. 2.6.9-rc2-mm1. This patch
minus the hashtable initialization fix has been successfully tested on 2x
ppc64, 2x alpha, 8x ia64, 6x sparc64, and 4x x86-64, all vs.
2.6.9-rc2-mm1. This precise version of the patch has been successfully
tested on 8x ia32 against 2.6.9-rc2-mm1 and 6x sparc64 vs. both
2.6.9-rc2-mm1 and 2.6.9-rc2-mm2.
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
James Morris [Tue, 19 Oct 2004 01:17:18 +0000 (18:17 -0700)]
[PATCH] SELinux: allow all filesystems to specify fscreate mount option
The patch below allows all types of filesystems to specify the fscreate
mount option (which is used to specify the security context of the
filesystem itself). This was previously only available for filesystems
with full xattr security labeling, but is also potentially required for
filesystems with e.g. psuedo xattr labeling such as devpts and tmpfs.
An example of use is to specify at mount time the fs security context of a
tmpfs filesystem, overriding the default specified in policy for that
filesystem.
This patch has been in the Fedora kernel for some weeks with no problems.
Signed-off-by: James Morris <jmorris@redhat.com> Signed-off-by: Stephen Smalley <sds@epoch.ncsc.mil> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] xattr: re-introduce validity check before xattr cache insert
* ext[23]_xattr_list():
- Before inserting an xattr block into the cache, make sure that the
block is not corrupted. The check got moved after inserting into the
cache in the xattr consolidation patches, so corrupted blocks could become
visible to cache users.
- Take a variable out of the loop that calls the ->list handlers.
* A few cosmetic changes.
Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
James Morris [Tue, 19 Oct 2004 01:16:53 +0000 (18:16 -0700)]
[PATCH] xattr consolidation v3 - tmpfs
This patch adds xattr support to tmpfs, and a security xattr handler. The
purpose of this is to allow udev to be mounted on tmpfs, as used currently by
Fedora.
Original patch from: Luke Kenneth Casson Leighton <lkcl@lkcl.net>.
Signed-off-by: James Morris <jmorris@redhat.com> Signed-off-by: Stephen Smalley <sds@epoch.ncsc.mil> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
James Morris [Tue, 19 Oct 2004 01:16:03 +0000 (18:16 -0700)]
[PATCH] xattr consolidation v3 - LSM
This patch replaces the dentry parameter with an inode in the LSM
inode_{set|get|list}security hooks, in keeping with the ext2/ext3 code.
dentries are not needed here.
Signed-off-by: James Morris <jmorris@redhat.com> Signed-off-by: Stephen Smalley <sds@epoch.ncsc.mil> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
James Morris [Tue, 19 Oct 2004 01:15:51 +0000 (18:15 -0700)]
[PATCH] xattr consolidation v3 - generic xattr API
This patch consolidates common xattr handling logic into the core fs code,
with modifications suggested by Christoph Hellwig (hang off superblock, remove
locking, use generic code as methods), for use by ext2, ext3 and devpts, as
well as upcoming tmpfs xattr code.
Signed-off-by: James Morris <jmorris@redhat.com> Signed-off-by: Stephen Smalley <sds@epoch.ncsc.mil> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Ulrich Drepper [Tue, 19 Oct 2004 01:15:27 +0000 (18:15 -0700)]
[PATCH] Simplify last lib/idr.c change
The last change to alloc_layer in lib/idr.c unnecessarily complicates
the code and depending on the definition of spin_unlock will cause worse
code to be generated than necessary. The following patch should improve
the situation.
Haroldo Gamal [Tue, 19 Oct 2004 01:15:14 +0000 (18:15 -0700)]
[PATCH] smbfs does not honor uid, gid, file_mode and dir_mode supplied by user mount
This patch fixes "Samba Bugzilla Bug 999". The last version (2.6.8.1) of
smbfs kernel module do not honor uid, gid, file_mode and dir_mode supplied
by user during mount. This bug is also logged as "Kernel Bug Tracker Bug
3330".
To fully work, some modifications are needed to samba smbmount.c and
smbmnt.c files. Those patches are available at Samba and Kernel Bug
Tracker pages.
After those patches, if the user do not supply any of the parameters above,
the uid, gid, file_mode and dir_mode on the server will be used by the
client.
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Andi Kleen [Tue, 19 Oct 2004 01:14:38 +0000 (18:14 -0700)]
[PATCH] x86-64/i386: add mce tainting
This patch adds machine check tainting. When a handled machine check
occurs the oops gets a new 'M' flag. This is useful to ignore machines
with hardware problems in oops reports.
On i386 a thermal failure also sets this flag.
Done for x86-64 and i386 so far.
Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Dipankar Sarma [Tue, 19 Oct 2004 01:14:13 +0000 (18:14 -0700)]
[PATCH] Remove d_bucket
Tested using dcachebench and hevy rename test.
http://lse.sourceforge.net/locking/dcache/rename_test/
While going over dcache code, I realized that d_bucket which was introduced
to prevent hash chain traversals from going into an infinite loop earlier,
is no longer necessary. Originally, when RCU based lock-free lookup was
first introduced, dcache hash chains used list_head. Hash chain traversal
was terminated when dentry->next reaches the list_head in the hash bucket.
However, if renames happen during a lock-free lookup, a dentry may move to
different bucket and subsequent hash chain traversal from there onwards may
not see the list_head in the original bucket at all. In fact, this would
result in the list_head in the bucket interpreted as a list_head in dentry
and bad things will happen after that. Once hlist based hash chains were
introduced in dcache, the termination condition changed and lock-free
traversal would be safe with NULL pointer based termination of hlists.
This means that d_bucket check is no longer required.
There still exist some theoritical livelocks like a dentry getting
continuously moving and lock-free look-up never terminating. But that
isn't really any worse that what we have. In return for these changes, we
reduce the dentry size by the size of a pointer. That should make akpm and
mpm happy.
Dipankar Sarma [Tue, 19 Oct 2004 01:14:01 +0000 (18:14 -0700)]
[PATCH] Fix dcache lookup
__d_lookup() has leftover stuff from earlier code to protect it against
rename. The smp_rmb() there was needed for the sequence counter logic.
Original dcache_rcu had :
+ move_count = dentry->d_move_count;
+ smp_rmb();
+
if (dentry->d_name.hash != hash)
continue;
if (dentry->d_parent != parent)
continue;
This was to make sure that comparisons didn't happen before before the
sequence counter was snapshotted. This logic is now gone and memory
barrier is not needed. Removing this should also improve performance.
The other change is the leftover smp_read_barrier_depends(), later
converted to rcu_dereference(). Originally, the name comparison was not
protected against d_move() and there could have been a mismatch of
allocation size of the name string and dentry->d_name.len. This was
avoided by making the qstr update in dentry atomic using a d_qstr pointer.
Now, we do ->d_compare() or memcmp() with the d_lock held and it is safe
against d_move(). So, there is no need to rcu_dereference() anything. In
fact, the current code is meaningless.
[PATCH] cleanup: time.h, times.h, timex.h and jiffies.h
This patch moves some definitions among time.h, times.h, timex.h and
jiffies.h. The purpose is to sort all jiffies related functions to
jiffies.h, to get rid of the cyclic dependency between time.h & timex.h and
to move all #include lines to the start of the header files.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] cleanup: move call to update_process_times.
For non-smp kernels the call to update_process_times is done in the
do_timer function. It is more consistent with smp kernels to move this
call to the architecture file which calls do_timer.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
These had been officially deprecated since Rusty's module rewrite, but
never got the __deprecated marker. The only remaining users are drm and
mtd, so we'll get some warnings for common builds. But maybe that's the
only way to get the drm people to fix the mess :)
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When building external modules, MODVERDIR is relative to the external
module instead of in the kernel source tree. Use the MODVERDIR environment
variable instead of the hard-coded path in modpost.
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] make console_conditional_schedule() __sched and use cond_resched()
Relatively minor add-on (not necessarily tied to it or required to be taken
or a fix for any bug). Since cond_resched() is using PREEMPT_ACTIVE now,
it may be useful to update the open-coded instance of cond_resched() to use
the generic call. Also, it should probably be __sched so the caller shows
up in wchan.
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] Incorrect PCI interrupt assignment on ES7000 for platform GSI
In arch/i386/kernel/acpi/boot.c, platform GSI does not propagate back from
mp_register_gsi() to a calling routine which results in IRQ to be set for
wrong GSI. This causes most of the PCI slots on the first PCI module to
fail. This patch fixes the problem by returning new GSI back to
acpi_register_gsi().
Ian Kent [Tue, 19 Oct 2004 01:11:20 +0000 (18:11 -0700)]
[PATCH] autofs4: allow map update recognition
Having recently repaired autofs' ability to recognise updates to maps
dynamically I found I needed to reintroduce the directory inode lookup
method (I broke the update recognition several versions ago, oops).
This patch does this and applies cleanly against 2.6.9-rc1-mm4.
As far as I can tell from testing it doesn't introduce any backward
incompatibilities.
Signed-off-by: Ian Kent <raven@themaw.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Zwane Mwaikambo [Tue, 19 Oct 2004 01:11:08 +0000 (18:11 -0700)]
[PATCH] Allow multiple inputs in alternative_input
I had to use the following patch to allow multiple arguments to be passed
down to the asm stub for alternative_input whilst writing alternatives for
mwait code, it seems like a simple enough fix.
Signed-off-by: Zwane Mwaikambo <zwane@linuxpower.ca> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] pidhashing: enforce PID_MAX_LIMIT in sysctls
The pid_max sysctl doesn't enforce PID_MAX_LIMIT or sane lower bounds.
RESERVED_PIDS + 1 is the minimum pid_max that won't break alloc_pidmap(), and
PID_MAX_LIMIT may not be aligned to 8*PAGE_SIZE boundaries for unusual values
of PAGE_SIZE, so this also rounds up PID_MAX_LIMIT to it.
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I was informed that the vendor component of the copyright can't be clobbered
without more care, so this patch retains the older vendor, updating it only to
reflect the appropriate time period.
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Rewrite alloc_pidmap() to clarify control flow by eliminating all usage of
goto, honor pid_max and first available pid after last_pid semantics, make
only a single pass over the used portion of the pid bitmap, and update
copyrights to reflect ongoing maintenance by Ingo and myself.
Signed-off-by: William Irwin <wli@holomorphy.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Petr Vandrovec [Tue, 19 Oct 2004 01:09:53 +0000 (18:09 -0700)]
[PATCH] Add VIDIOC_S_CTRL_OLD to matroxfb
For several months I'm receiving complaints from matroxfb users that v4lctl
suddenly stops working for them on kernel upgrade.
Problem is that VIDIOC_S_CTRL was renumbered, but all distros still use old
VIDIOC_S_CTRL value (f.e. even xawtv-3.94 in Debian unstable still uses
old VIDIOC_S_CTRL definition).
So let's add this old VIDIOC_S_CTRL value (now named VIDIOC_S_CTRL_OLD) to
matroxfb's v4l handling.
Signed-off-by: Petr Vandrovec <vandrove@vc.cvut.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
projects / linux / log