We found a problem with x86_64 kernels with preemption enabled, where
having multiple tasks doing ptrace singlesteps around the same time will
cause the system to 'oops'. The problem seems that a task can get
preempted out of the do_debug() processing while it is running on the
DEBUG_STACK stack. If another task on that same cpu then enters do_debug()
and uses the same per-cpu DEBUG_STACK stack, the previous preempted tasks's
stack contents can be corrupted, and the system will oops when the
preempted task is context switched back in again.
The typical oops looks like the following:
Unable to handle kernel paging request at ffffffffffffffae RIP: <ffffffff805452a1>{thread_return+34}
PGD 103027 PUD 102429067 PMD 0
Oops: 0002 [1] PREEMPT SMP
CPU 0
Modules linked in:
Pid: 3786, comm: ssdd Not tainted 2.6.15.2 #1
RIP: 0010:[<ffffffff805452a1>] <ffffffff805452a1>{thread_return+34}
RSP: 0018:ffffffff80824058 EFLAGS: 000136c2
RAX: ffff81017e12cea0 RBX: 0000000000000000 RCX: 00000000c0000100
RDX: 0000000000000000 RSI: ffff8100f7856e20 RDI: ffff81017e12cea0
RBP: 0000000000000046 R08: ffff8100f68a6000 R09: 0000000000000000
R10: 0000000000000000 R11: ffff81017e12cea0 R12: ffff81000c2d53e8
R13: ffff81017f5b3be8 R14: ffff81000c0036e0 R15: 000001056cbfc899
FS: 00002aaaaaad9b00(0000) GS:ffffffff80883800(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffffffffffffffae CR3: 00000000f6fcf000 CR4: 00000000000006e0
Process ssdd (pid: 3786, threadinfo ffff8100f68a6000, task ffff8100f7856e20)
Stack: ffffffff808240d8 ffffffff8012a84a ffff8100055f6c00 0000000000000020
0000000000000001 ffff81000c0036e0 ffffffff808240b8 0000000000000000
0000000000000000 0000000000000000
Call Trace: <#DB>
<ffffffff8012a84a>{try_to_wake_up+985}
<ffffffff8012c0d3>{kick_process+87}
<ffffffff8013b262>{signal_wake_up+48}
<ffffffff8013b5ce>{specific_send_sig_info+179}
<ffffffff80546abc>{_spin_unlock_irqrestore+27}
<ffffffff8013b67c>{force_sig_info+159}
<ffffffff801103a0>{do_debug+289} <ffffffff80110278>{sync_regs+103}
<ffffffff8010ed9a>{paranoid_userspace+35}
Unable to handle kernel paging request at 00007fffffb7d000 RIP: <ffffffff8010f2e4>{show_trace+465}
PGD f6f25067 PUD f6fcc067 PMD f6957067 PTE 0
Oops: 0000 [2] PREEMPT SMP
This patch disables preemptions for the task upon entry to do_debug(), before
interrupts are reenabled, and then disables preemption before exiting
do_debug(), after disabling interrupts. I've noticed that the task can be
preempted either at the end of an interrupt, or on the call to
force_sig_info() on the spin_unlock_irqrestore() processing. It might be
better to attempt to code a fix in entry.S around the code that calls
do_debug().
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The orinoco wireless driver can support the SMC 2532W-B PC Card, so add the
id for it.
Signed-off-by: Jesse Allen <the3dfxdude@gmail.com>
Cc: Pavel Roskin <proski@gnu.org>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Unfortunately, the reiserfs_attrs_cleared bit in the superblock flag can
lie. File systems have been observed with the bit set, yet still contain
garbage in the stat data field, causing unpredictable results.
This patch backs out the enable-by-default behavior.
It eliminates the changes from: d50a5cd860,
and ef5e5414e7.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
net/bridge/br_netfilter.c: In function `br_nf_post_routing':
net/bridge/br_netfilter.c:808: warning: implicit declaration of function `has_bridge_parent'
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Cc: Harald Welte <laforge@netfilter.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add fstatat64 support to s390 in order to follow changes with
commit cff2b76009 .
Also fixes compilation for 31 bit.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Rename get_support function to pcwd_check_temperature_support
so that it is clearer what the function does.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
The following makes drivers/char/watchdog/sa1100_wdt.c sparse clean.
(similar to the other watchdog drivers)
Signed-off-by: Ian Campbell <icampbell@arcom.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
drivers/video/fbmem.c:1567: warning: 'video_setup' defined but not used
Acked-by: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The BUS_I2C option is neither available (since there is no VISWS option in
the kernel) nor does it have any effect - so why not remove it?
Based on a report by Jean-Luc Leger <reiga@dspnet.fr.eu.org>.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- tipar_open(): fix unsigned comparison
- tipar_open(): don't permit NULL pardevice (probably unneeded given the
above fix).
- tipar_init_module(): handle the situation where parport_register_driver()
failed to register any devices (parport_register_driver() drops the ->attach
return value on the floor).
This probably makes fixes#1 and #2 unneeded.
- tipar_init_module(): fix various error-path resource leaks.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Right now in __constant_test_bit for the s390 there is an extra set of ()
surrounding the calculation. This patch simply removes one set of () that is
surrounding the whole clause.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Based on a patch from Maximilian Attems <maks@sternwelten.at> . Nothing in
asm-s390/setup.h is of interest for user space.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add support for unshare system call.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add missing smp_cpu_not_running define to avoid build warnings in the non smp
case.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Update URL for s390 and add maintainers for s390 networking and zfcp driver.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initiliazing of cpu_possible_map was done in smp_prepare_cpus which is way too
late. Therefore assign a static value to cpu_possible_map, since we don't
have access to max_cpus in setup_arch.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When the sclp interface takes very long to serve a request, the sclp core
driver will report a failed request to the sclp tty driver even though the
request is still being processed by the sclp interface. Eventually the sclp
interface completes the request and updates some fields in the request buffer
which leads to a corrupted tty pages list. The next time function
sclp_tty_write_room is called, the corrupted list will be traversed, resulting
in an oops.
To avoid this remove the busy retry limit and increase retry intervals.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix locking in __chp_add() and s390_subchannel_remove_chpid(): Need to
disable/enable because they are always called from a thread (and not
directly from a machine check...)
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Lost a few hours debugging an early-bootup fault within printk itself,
which manifested itself as a hard to debug early hang.
This patch makes it much easier by printing out early faults via
early_printk(), which function is a lot simpler than a full printk, and
hence more likely to succeed in emergencies. (We do not recover from early
faults anyway, so there's no loss from not having these messages in the
normal printk buffer.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This puts the variables and the way to get to reclaim_mapped in one block.
And allows zone_reclaim or other things to skip the determination (maybe
this whole block of code does not belong into refill_inactive_zone()?)
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
shrink_zone() already increments reclaim_in_progress. No need to do it in
balance_pgdat.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
shrink_list() and refill_inactive() check all ptes pointing to a page for
reference bits in order to decide if the page should be put on the active
list. This is not necessary for zone_reclaim since we are only interested
in removing unmapped pages. Skip the checks in both functions.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With David Woodhouse <dwmw2@infradead.org>
select() presently has a habit of increasing the value of the user's
`timeout' argument on return.
We were writing back a timeout larger than the original. We _deliberately_
round up, since we know we must wait at _least_ as long as the caller asks
us to.
The patch adds a couple of helper functions for magnitude comparison of
timespecs and of timevals, and uses them to prevent the various poll and
select functions from returning a timeout which is larger than the one which
was passed in.
The patch also fixes a bug in compat_sys_pselect7(): it was adding the new
timeout value to the old one and was returning that. It should just return
the new timeout value.
(We have various handy timespec/timeval-to-from-nsec conversion functions in
time.h. But this code open-codes it all).
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andi Kleen <ak@muc.de>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: george anzinger <george@mvista.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[description from AK]
The IBM Summit 3 chipset doesn't implement the HPET timer replacement
option. Since the current Linux code relies on it use a mixed mode with
both PIT for the interrupt and HPET counters for the time keeping. That
was already implemented, but didn't work properly because it was still
using the last interrupt offset in HPET. This resulted in x460 not
booting. Fix this up by using the free running HPET counter.
Shouldn't affect any other machine because they either use full HPET mode
or no HPET at all.
TBD needs a similar 32bit fix.
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com>
Cc: Bob Picco <bob.picco@hp.com>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Matt Waddel <Matt.Waddel@freescale.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The *at patches introduced fstatat and, due to inusfficient research, I
used the newfstat functions generally as the guideline. The result is that
on 32-bit platforms we don't have all the information needed to implement
fstatat64.
This patch modifies the code to pass up 64-bit information if
__ARCH_WANT_STAT64 is defined. I renamed the syscall entry point to make
this clear. Other archs will continue to use the existing code. On x86-64
the compat code is implemented using a new sys32_ function. this is what
is done for the other stat syscalls as well.
This patch might break some other archs (those which define
__ARCH_WANT_STAT64 and which already wired up the syscall). Yet others
might need changes to accomodate the compatibility mode. I really don't
want to do that work because all this stat handling is a mess (more so in
glibc, but the kernel is also affected). It should be done by the arch
maintainers. I'll provide some stand-alone test shortly. Those who are
eager could compile glibc and run 'make check' (no installation needed).
The patch below has been tested on x86 and x86-64.
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Patch from Ben Dooks
Define the bits for the two board control latches
that control various items on the H1940 iPAQ.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Serial drivers in general should not write uart_info->flags - they're
private to serial_core. Serial drivers have no need to fiddle with
tty->alt_speed, nor manipulate TTY_IO_ERROR in tty->flags. Fix the
ioc4 serial driver for both these points by simply removing the
offending code.
Acked-by: pfg@sgi.com
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/s390/kernel/compat_signal.c:199: error: conflicting types for 'do_sigaction'
include/linux/sched.h:1115: error: previous declaration of 'do_sigaction' was here
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adds some additional comments in order to help others figure out how
exactly the code works. And fix a variable name.
Also swap_page does need to ignore all reference bits when unmapping a
page. Otherwise we may have to repeatedly unmap a frequently touched page.
So change the try_to_unmap parameter to 1.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Prevent stalled processing of received data when a driver allocates tty
buffer space but does not immediately follow the allocation with more data
and a call to schedule receive tty processing. (example: hvc_console) This
bug was introduced by the first locking patch for the new tty buffering.
Signed-off-by: Paul Fulghum <paulkf@microgate.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Prevents deadlock situation between
kmem_cache_create()/kmem_cache_destory(), and kmem_cache_create() /cpu
hotplug. The locking order probably got moved over time.
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
sys_shmdt() can manage shm segments which are covered by multiple vmas. (This
can happen when a user uses mprotect() after shmat().)
This works well if shm is aligned to PAGE_SIZE, but if not, the last
segment cannot be detached. It is because a comparison in sys_shmdt()
(vma->vm_end - addr) < size
addr == return address of shmat()
size == shmsize, argments to shmget()
size should be aligned to PAGE_SIZE before being compared with vma->vm_end,
which is aligned.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When panic_timeout is zero, suppress triggering a nested panic due to soft
lockup detection.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initialising cpu_possible_map to all-ones with CONFIG_HOTPLUG_CPU means that
a) All for_each_cpu() loops will iterate across all NR_CPUS CPUs, rather
than over possible ones. That can be quite expensive.
b) Soon we'll be allocating per-cpu areas only for possible CPUs. So with
CPU_MASK_ALL, we'll be wasting memory.
I also switched voyager over to not use CPU_MASK_ALL in the non-CPU-hotplug
case. Should be OK..
I note that parisc is also using CPU_MASK_ALL. Suggest that it stop doing
that.
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Paul Jackson <pj@sgi.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Zwane Mwaikambo <zwane@linuxpower.ca>
Cc: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We are setting up sources for building external modules like this:
/usr/src/linux-obj> # create a .config file
/usr/src/linux-obj> make -C /usr/src/linux O=$PWD oldconfig
/usr/src/linux-obj> make -C /usr/src/linux O=$PWD prepare
/usr/src/linux-obj> make -C /usr/src/linux O=$PWD scripts
/usr/src/linux-obj> make -C /usr/src/linux O=$PWD clean
After that, external modules can be built with:
/usr/src/module> make -C /usr/src/linux-obj M=$PWD
This fails for ppc32 because the `make clean' removes the
arch/powerpc/include directory. This should be done in archmrproper
instead of in archclean.
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove bogus comment from init function which could lead to the assumption
that cpu_possible_map is setup in smp_prepare_cpus().
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It is possible that the reserved crashkernel region can be overlapped with
initrd since the bootloader sets the initrd location. When the initrd
region is freed, the second kernel memory will not be contiguous. The
Kexec_load can cause an oops since there is no contiguous memory to write
the second kernel or this memory could be used in the first kernel itself
and may not be part of the dump. For example, on powerpc, the initrd is
located at 36MB and the crashkernel starts at 32MB. The kexec_load caused
panic since writing into non-allocated memory (after 36MB). We could see
the similar issue even on other archs.
One possibility is to move the initrd outside of crashkernel region. But,
the initrd region will be freed anyway before the system is up. This patch
fixes this issue and frees only regions that are not part of crashkernel
memory in case overlaps.
Signed-off-by: Haren Myneni <haren@us.ibm.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
