I think the following patch should go into the kernel, until the ISDN/CAPI
guys create the real fix for this issue.
The issue is a concurrency issue with some internal CAPI data structure
which can crash the kernel.
On my FritzCard DSL with the AVM driver it crashes about once a day without
this workaround patch. With this workaround patch it's rock-stable (at
least on UP, but I don't see why this shouldn't work on SMP as well. But
maybe I'm missing something.)
This workaround is kind of a sledgehammer which inserts a global lock to
wrap around all the critical sections. Of course, this is a scalability
issue, if you have many ISDN/CAPI cards. But it prevents a crash. So I
vote for this fix to get merged, until people come up with a better
solution. Better have a stable kernel that's less scalable, than a
crashing and useless kernel.
This bug is in the kernel since 2.6.15 (at least).
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Cc: Kai Germaschewski <kai.germaschewski@gmx.de>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rename the macro CONFIG_HISAX_HFC4S8S_PCIMEM to simply HISAX_HFC4S8S_PCIMEM so
that it no longer resembles a user-settable kernel config macro.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Based on advice from K. Keil, rename the special debug option
CONFIG_SERIAL_NOPAUSE_IO to ELSA_SERIAL_NOPAUSE_IO so it no longer resembles a
user-selectable kernel config option.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rename some of the debugging macros for ISDN AVM so that they don't resemble
kernel config settings, as they're primarily for author debugging instead.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add proper prototypes in a header file for global code under
drivers/isdn/sc/.
Since the GNU C compiler is now able do tell us that caller and callee
disagreed about the number of arguments of setup_buffers(), this patch
also fixes this bug.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- add functions prototypes for some global functions to header files
- remove unneeded "extern"s from some function prototypes
You might note that this patch results in a new warning - that's due to the
fact that with a proper prototype gcc is able to discover a broken
work_struct conversion.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Eric Wollesen ported the Bluesmoke Memory Controller driver for the Intel
5000X/V/P (Blackford/Greencreek) chipset to the in kernel EDAC model.
This patch incorporates those required changes to the edac_mc.c and edac_mc.h
core files by added new Fully Buffered DIMM interface to the EDAC Core module.
Signed-off-by: eric wollesen <ericw@xmtp.net>
Signed-off-by: doug thompson <norsk5@xmission.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is an attempt of providing an interface for memory scrubbing control in
EDAC.
This patch modifies the EDAC Core to provide the Interface for memory
controller modules to implment.
The following things are still outstanding:
- K8 is the first implemenation,
The patch provide a method of configuring the K8 hardware memory scrubber
via the 'mcX' sysfs directory. There should be some fallback to a generic
scrubber implemented in software if the hardware does not support
scrubbing.
Or .. the scrubbing sysfs entry should not be visible at all.
- Only works with SDRAM, not cache,
The K8 can scrub cache and l2cache also - but I think this is not so
useful as the cache is busy all the time (one hopes).
One would also expect that cache scrubbing requires hardware support.
- Error Handling,
I would like that errors are returned to the user in "terms of file
system".
- Presentation,
I chose Bandwidth in Bytes/Second as a representation of the scrubbing
rate for the following reasons:
I like that the sysfs entries are sort-of textual, related to something
that makes sense instead of magical values that must be looked up.
"My People" wants "% main memory scrubbed per hour" others prefer "%
memory bandwidth used" as representation, "bandwith used" makes it easy to
calculate both versions in one-liner scripts.
If one later wants to scrub cache, the scaling becomes wierd for K8
changing from "blocks of 64 byte memory" to "blocks of 64 cache lines" to
"blocks of 64 bit". Using "bandwidth used" makes sense in all three cases,
(I.M.O. anyway ;-).
- Discovery,
There is no way to discover the possible settings and what they do
without reading the code and the documentation.
*I* do not know how to make that work in a practical way.
- Bugs(??),
other tools can set invalid values in the memory scrub control register,
those will read back as '-1', requiring the user to reset the scrub rate.
This is how *I* think it should be.
- Afflicting other areas of code,
I made changes to edac_mc.c and edac_mc.h which will show up globally -
this is not nice, it would be better that the memory scrubbing fuctionality
and interface could be entirely contained within the memory controller it
applies to.
Frithiof Jensen
edac_mc.c and its .h file is a CORE helper module for EDAC
driver modules. This provides the abstraction for device specific
drivers. It is fine to modify this CORE to provide help for
new features of the the drivers
doug thompson
Signed-off-by: Frithiof Jensen <frithiof.jensen@ericson.com>
Signed-off-by: doug thompson <norsk5@xmission.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The reading of the DRA registers should be a byte at a time (one register at a
time) instead of 4 bytes at a time (four registers). Reading a dword at a
time retrieves erroneous information from all but the first register. A
change was made to read in each register in a loop prior to using the data in
those registers.
Signed-off-by: Brian Pomerantz <bapper@mvista.com>
Signed-off-by: Dave Jiang <djiang@mvista.com>
Signed-off-by: Doug Thompson <norsk5@xmission.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Andi Kleen <ak@suse.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Of kernel subsystems that work with pids the tty layer is probably the largest
consumer. But it has the nice virtue that the assiation with a session only
lasts until the session leader exits. Which means that no reference counting
is required. So using struct pid winds up being a simple optimization to
avoid hash table lookups.
In the long term the use of pid_nr also ensures that when we have multiple pid
spaces mixed everything will work correctly.
Signed-off-by: Eric W. Biederman <eric@maxwell.lnxi.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Every call to is_orphaned_pgrp passed in process_group(current) which is racy
with respect to another thread changing our process group. It didn't bite us
because we were dealing with integers and the worse we would get would be a
stale answer.
In switching the checks to use struct pid to be a little more efficient and
prepare the way for pid namespaces this race became apparent.
So I simplified the calls to the more specialized is_current_pgrp_orphaned so
I didn't have to worry about making logic changes to avoid the race.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To properly implement a pid namespace I need to deal exclusively in terms of
struct pid, because pid_t values become ambiguous.
To this end session_of_pgrp is transformed to take and return a struct pid
pointer. To avoid the need to worry about reference counting I now require my
caller to hold the appropriate locks. Leaving callers repsonsible for
increasing the reference count if they need access to the result outside of
the locks.
Since session_of_pgrp currently only has one caller and that caller simply
uses only test the result for equality with another process group, the locking
change means I don't actually have to acquire the tasklist_lock at all.
tiocspgrp is also modified to take and release the lock. The logic there is a
little more complicated but nothing I won't need when I convert pgrp of a tty
to a struct pid pointer.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The code to look at tty_old_pgrp and send SIGHUP and SIGCONT when it is
present only executes when disassociate_ctty is called from do_exit. Make
this clear by adding an explict on_exit check, and explicitly setting
tty_old_pgrp to 0.
In addition fix the locking by reading tty_old_pgrp under the siglock.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The aim of this patch set is to start wrapping up the struct pid conversions.
As such this patchset culminates with the removal of kill_pg, kill_pg_info,
__kill_pg_info, do_each_task_pid, and while_each_task_pid.
kill_proc, daemonize, and kernel_thread are still in my sights but there is
still work to get to them.
The first three are basic cleanups around disassociate_ctty, while working on
converting it I found several issues. tty_old_pgrp can be a tricky concept to
wrap your head around.
1 tty: Make __proc_set_tty static.
2 tty: Clarify disassociate_ctty
3 tty: Fix the locking for signal->session in disassociate_ctty
These just stop using the old helper functions.
4 signal: Use kill_pgrp not kill_pg in the sunos compatibility code.
5 signal: Rewrite kill_something_info so it uses newer helpers.
Then the grind to convert the tty layer and all of it's helper functions to
struct pid.
6 pid: Make session_of_pgrp use struct pid instead of pid_t.
7 pid: Use struct pid for talking about process groups in exit.c
8 pid: Replace is_orphaned_pgrp with is_current_pgrp_orphaned
9 tty: Update the tty layer to work with struct pid.
A final helper function update.
10 pid: Replace do/while_each_task_pid with do/while_each_pid_task
And the removal of the functions that are now unused.
11 pid: Remove now unused do_each_task_pid and while_each_task_pid
12 pid: Remove the now unused kill_pg kill_pg_info and __kill_pg_info
All of these should be fairly simple and to the point.
This patch:
Currently all users of __proc_set_tty are in tty_io.c so make the function
static.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is adds a simple SPI EEPROM driver, providing access to the EEPROM
through sysfs much like the I2C "eeprom" driver ... except this driver
supports write access, and multiple EEPROM sizes.
From: "Tuppa, Walter" <walter.tuppa@siemens.com>
Since I have EEPROMs on SPI with different address sizing, I made some
changes to your at25.c to support them. Works perfectly. (Also includes a
small bugfix for the "what size address" test.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Walter Tuppa <walter.tuppa@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
