Commit Graph

6219 Commits

Author SHA1 Message Date
Vivek Goyal
1a75a3f068 [PATCH] i386 kdump timer vector lockup fix
Porting the patch I posted for x86_64 to i386.

http://marc.theaimsgroup.com/?l=linux-kernel&m=114178139610707&w=2

o While using kdump, after a system crash when second kernel boots, timer
  vector gets (0x31) locked and CPU does not see timer interrupts
  travelling from IOAPIC to APIC.  Currently it does not lead to boot
  failure in second kernel as timer interrupts continues to come as ExtInt
  through LAPIC directly, but fixing it is good in case some boards do not
  support the other mode.

o After a system crash, it is not safe to service interrupts any more,
  hence interrupts are disabled.  This leads to pending interrupts at
  LAPIC.  LAPIC sends these interrupts to the CPU during early boot of
  second kernel.  Other pending interrupts are discarded saying unexpected
  trap but timer interrupt is serviced and CPU does not issue an LAPIC EOI
  because it think this interrupt came from i8259 and sends ack to 8259.
  This leads to vector 0x31 locking as LAPIC does not clear respective ISR
  and keeps on waiting for EOI.

o This patch issues extra EOI for the pending interrupts who have ISR set.

o Though today only timer seems to be the special case because in early
  boot it thinks interrupts are coming from i8259 and uses
  mask_and_ack_8259A() as ack handler and does not issue LAPIC EOI.  But
  probably doing it in generic manner for all vectors makes sense.

Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:50 -08:00
Brian Gerst
3ccfb81e87 [PATCH] Remove long dead i386 floppy asm code
It's been disabled since v2.1.88

Signed-off-by: Brian Gerst <bgerst@didntduck.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:50 -08:00
Nick Piggin
93fac7041f [PATCH] mm: schedule find_trylock_page() removal
find_trylock_page() is an odd interface in that it doesn't take a reference
like the others.  Now that XFS no longer uses it, and its last remaining
caller actually wants an elevated refcount, opencode that callsite and
schedule find_trylock_page() for removal.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:49 -08:00
Christoph Lameter
9bf9e89c3d [PATCH] migrate_pages_to() must be defined for the no swap case
Fix migrate_pages_to() definition.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:49 -08:00
Adrian Bunk
0500abf521 [PATCH] drivers/mtd/: small cleanups
- chips/sharp.c: make two needlessly global functions static

- move some declarations to a header file where they belong to

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:48 -08:00
Ingo Molnar
48b192686d [PATCH] sem2mutex: drivers/mtd/
Semaphore to mutex conversion.

The conversion was generated via scripts, and the result was validated
automatically via a script as well.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:48 -08:00
Linus Torvalds
ce362c0092 Merge git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6: (24 commits)
  [PARISC] Fix double free when removing HIL drivers
  [PARISC] Add atomic_sub_and_test
  [PARISC] Enabled some NLS modules in a500, b180 and c3000 defconfigs
  [PARISC] Kill duplicated EXPORT_SYMBOL warnings
  [PARISC] Move ioremap EXPORT_SYMBOL from parisc_ksyms.c
  [PARISC] Make local_t use atomic_long_t
  [PARISC] Update defconfigs
  [PARISC] Add PREEMPT support
  [PARISC] More useful readwrite lock helpers
  [PARISC] Convert HIL drivers to use input_allocate_device
  [PARISC] Fixup CONFIG_EISA a bit
  [PARISC] getsockopt should be ENTRY_COMP
  [PARISC] Remove obsolete CONFIG_DEBUG_IOREMAP
  [PARISC] Temporary FIXME for ioremapping EISA regions
  [PARISC] Enable ioremap functionality unconditionally
  [PARISC] Fix stifb with IOREMAP and a 64-bit kernel
  [PARISC] Add CONFIG_HPPA_IOREMAP to conditionally enable ioremap
  [PARISC] Add STRICT_MM_TYPECHECKS
  [PARISC] Fix IOREMAP with a 64-bit kernel
  [PARISC] Add parisc implementation of flush_kernel_dcache_page()
  ...
2006-03-30 15:04:13 -08:00
Linus Torvalds
064c94f9da Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
  IB/mad: RMPP support for additional classes
  IB/mad: include GID/class when matching receives
  IB/mthca: Fix section mismatch problems
  IPoIB: Fix oops with raw sockets
  IB/mthca: Fix check of size in SRQ creation
  IB/srp: Fix unmapping of fake scatterlist
2006-03-30 14:32:38 -08:00
Linus Torvalds
256414dee4 Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev:
  [PATCH] sata_mv: three bug fixes
  [PATCH] libata: ata_dev_init_params() fixes
  [PATCH] libata: Fix interesting use of "extern" and also some bracketing
  [PATCH] libata: Simplex and other mode filtering logic
  [PATCH] libata - ATA is both ATA and CFA
  [PATCH] libata: Add ->set_mode hook for odd drivers
  [PATCH] libata: BMDMA handling updates
  [PATCH] libata: kill trailing whitespace
  [PATCH] libata: add FIXME above ata_dev_xfermask()
  [PATCH] libata: cosmetic changes in ata_bus_softreset()
  [PATCH] libata: kill E.D.D.
2006-03-30 14:29:20 -08:00
Linus Torvalds
d1127e40e8 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
  [IA64] ioremap() should prefer WB over UC
  [IA64] Add __mca_table to the DISCARD list in gate.lds
  [IA64] Move __mca_table out of the __init section
  [IA64] simplify some condition checks in iosapic_check_gsi_range
  [IA64] correct some messages and fixes some minor things
  [IA64-SGI] fix for-loop in sn_hwperf_geoid_to_cnode()
  [IA64-SGI] sn_hwperf use of num_online_cpus()
  [IA64] optimize flush_tlb_range on large numa box
  [IA64] lazy_mmu_prot_update needs to be aware of huge pages
2006-03-30 12:38:18 -08:00
Jens Axboe
5abc97aa25 [PATCH] splice: add support for SPLICE_F_MOVE flag
This enables the caller to migrate pages from one address space page
cache to another.  In buzz word marketing, you can do zero-copy file
copies!

Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-30 12:28:18 -08:00
Jens Axboe
5274f052e7 [PATCH] Introduce sys_splice() system call
This adds support for the sys_splice system call. Using a pipe as a
transport, it can connect to files or sockets (latter as output only).

From the splice.c comments:

   "splice": joining two ropes together by interweaving their strands.

   This is the "extended pipe" functionality, where a pipe is used as
   an arbitrary in-memory buffer. Think of a pipe as a small kernel
   buffer that you can use to transfer data from one end to the other.

   The traditional unix read/write is extended with a "splice()" operation
   that transfers data buffers to or from a pipe buffer.

   Named by Larry McVoy, original implementation from Linus, extended by
   Jens to support splicing to files and fixing the initial implementation
   bugs.

Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-30 12:28:18 -08:00
Kyle McMartin
4da9f131a7 [PARISC] Add atomic_sub_and_test
Define atomic_sub_and_test to fix build failures.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:59 +00:00
Kyle McMartin
2746ae14fe [PARISC] Make local_t use atomic_long_t
As done in asm-generic/local.h in mainline. Otherwise local_t was 32-bit
even on a 64-bit kernel.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:56 +00:00
Kyle McMartin
50a34dbd61 [PARISC] Add PREEMPT support
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:54 +00:00
Kyle McMartin
bc8846c522 [PARISC] More useful readwrite lock helpers
spinlock.c needs _can_lock helpers. Rewrite _is_locked helpers to be
_can_lock helpers.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:53 +00:00
Helge Deller
10267cdd0c [PARISC] Fixup CONFIG_EISA a bit
Fix up some ISA/EISA stuff.

(Note: isa_ accessors have been removed from asm/io.h)

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:52 +00:00
Helge Deller
a41d3862df [PARISC] Remove obsolete CONFIG_DEBUG_IOREMAP
Remove CONFIG_DEBUG_IOREMAP, it's now obsolete and won't work anyway.
Remove it from lib/KConfig since it was only available on parisc.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:50 +00:00
Helge Deller
29ef829532 [PARISC] Enable ioremap functionality unconditionally
Enable CONFIG_HPPA_IOREMAP by default and remove all now unnecessary code.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:48 +00:00
Helge Deller
b8ce0aadcd [PARISC] Add CONFIG_HPPA_IOREMAP to conditionally enable ioremap
Instead of making it a #define in asm/io.h, allow user to select
to turn on IOREMAP from the config menu.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:46 +00:00
Helge Deller
b31059f763 [PARISC] Add STRICT_MM_TYPECHECKS
Add STRICT_MM_TYPECHECKS to page.h as other architectures do.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:45 +00:00
James Bottomley
ba57583396 [PARISC] Add parisc implementation of flush_kernel_dcache_page()
We need to do a little renaming of our original syntax because
of the difference in arguments.

Signed-off-by: James Bottomley <jejb@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:44 +00:00
James Bottomley
ab43227c8a [PARISC] Add parisc implementation of flush_anon_page()
This should now allow SG_IO and fuse to function correctly on our
platform.

Signed-off-by: James Bottomley <jejb@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:43 +00:00
Thibaut VARENE
a81dd18eb9 [PARISC] Clarify pdc_stable license terms
pdc_stable.c is explicitly licensed under GPL version 2.

Signed-off-by: Thibaut VARENE <varenet@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:41 +00:00
Jes Sorensen
3283a67d86 [IA64] Add __mca_table to the DISCARD list in gate.lds
Add __mca_table to the DISCARD list for the gate.lds linker script to
avoid broken linker references when linking the final vmlinux file.

Also add comment to include/asm-ia64/asmmacros.h to avoid anyone else
hitting this problem in the future.

Credits to James Bottomley <James.Bottomley@SteelEye.com> for spotting
the DISCARD list in gate.lds.S

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-03-30 09:04:19 -08:00
Hal Rosenstock
618a3c03fc IB/mad: RMPP support for additional classes
Add RMPP support for additional management classes that support it.
Also, validate RMPP is consistent with management class specified.

Signed-off-by: Hal Rosenstock <halr@voltaire.com>
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-30 07:19:51 -08:00
Alan Cox
5444a6f405 [PATCH] libata: Simplex and other mode filtering logic
Add a field to the host_set called 'flags' (was host_set_flags changed
to suit Jeff)
Add a simplex_claimed field so we can remember who owns the DMA channel
Add a ->mode_filter() hook to allow drivers to filter modes
Add docs for mode_filter and set_mode
Filter according to simplex state
Filter cable in core

This provides the needed framework to support all the mode rules found
in the PATA world. The simplex filter deals with 'to spec' simplex DMA
systems found in older chips. The cable filter avoids duplicating the
same rules in each chip driver with PATA. Finally the mode filter is
neccessary because drive/chip combinations have errata that forbid
certain modes with some drives or types of ATA object.

Drive speed setup remains per channel for now and the filters now use
the framework Tejun put into place which cleans them up a lot from the
older libata-pata patches.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-03-29 19:30:28 -05:00
Alan Cox
e35a9e01f2 [PATCH] libata: Add ->set_mode hook for odd drivers
Some hardware doesn't want the usual mode setup logic running. This
allows the hardware driver to replace it for special cases in the least
invasive way possible.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-03-29 19:30:27 -05:00
Alan Cox
4e5ec5dba2 [PATCH] libata: BMDMA handling updates
This is the minimal patch set to enable the current code to be used with
a controller following SFF (ie any PATA and early SATA controllers)
safely without crashes if there is no BMDMA area or if BMDMA is not
assigned by the BIOS for some reason.

Simplex status is recorded but not acted upon in this change, this isn't
a problem with the current drivers as none of them are for simplex
hardware. A following diff will deal with that.

The flags in the probe structure remain ->host_set_flags although Jeff
asked me to rename them, simply because the rename would break the usual
Linux rules that old code should break when there are changes. not
compile and run and then blow up/eat your computer/etc. Renaming this
later is a trivial exercise once a better name is chosen.

Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-03-29 19:30:27 -05:00
Jeff Garzik
e02a4cabfc Merge branch 'master' 2006-03-29 17:18:49 -05:00
Linus Torvalds
f3cab8a0b1 Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
  [NETFILTER]: Rename init functions.
  [TCP]: Fix RFC2465 typo.
  [INET]: Introduce tunnel4/tunnel6
  [NET]: deinline 200+ byte inlines in sock.h
  [ECONET]: Convert away from SOCKOPS_WRAPPED
  [NET]: Fix ipx/econet/appletalk/irda ioctl crashes
  [NET]: Kill Documentation/networking/TODO
  [TG3]: Update version and reldate
  [TG3]: Skip timer code during full lock
  [TG3]: Speed up SRAM access
  [TG3]: Fix PHY loopback on 5700
  [TG3]: Fix bug in 40-bit DMA workaround code
  [TG3]: Fix probe failure due to invalid MAC address
2006-03-29 11:29:33 -08:00
Linus Torvalds
76babde121 Merge git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (67 commits)
  [PATCH] powerpc: Remove oprofile spinlock backtrace code
  [PATCH] powerpc: Add oprofile calltrace support to all powerpc cpus
  [PATCH] powerpc: Add oprofile calltrace support
  [PATCH] for_each_possible_cpu: ppc
  [PATCH] for_each_possible_cpu: powerpc
  [PATCH] lock PTE before updating it in 440/BookE page fault handler
  [PATCH] powerpc: Kill _machine and hard-coded platform numbers
  ppc: Fix compile error in arch/ppc/lib/strcase.c
  [PATCH] git-powerpc: WARN was a dumb idea
  [PATCH] powerpc: a couple of trivial compile warning fixes
  powerpc: remove OCP references
  powerpc: Make uImage default build output for MPC8540 ADS
  powerpc: move math-emu over to arch/powerpc
  powerpc: use memparse() for mem= command line parsing
  ppc: fix strncasecmp prototype
  [PATCH] powerpc: make ISA floppies work again
  [PATCH] powerpc: Fix some initcall return values
  [PATCH] powerpc: Workaround for pSeries RTAS bug
  [PATCH] spufs: fix __init/__exit annotations
  [PATCH] powerpc: add hvc backend for rtas
  ...
2006-03-29 11:28:30 -08:00
Anton Blanchard
15e812ad84 [PATCH] powerpc: Remove oprofile spinlock backtrace code
Remove oprofile spinlock backtrace code now we have proper calltrace
support. Also make MMCRA sihv and sipr bits a variable since they may
change in future cpus. Finally, MMCRA should be a 64bit quantity.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-29 13:44:16 +11:00
Brian Rogan
6c6bd754bf [PATCH] powerpc: Add oprofile calltrace support
Add oprofile calltrace support to powerpc. Disable spinlock backtracing
now we can use calltrace info.

(Updated to work on both 32bit and 64bit by me).

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-29 13:44:16 +11:00
KAMEZAWA Hiroyuki
0e5519548f [PATCH] for_each_possible_cpu: powerpc
for_each_cpu() actually iterates across all possible CPUs.  We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs.  This is inefficient and
possibly buggy.

We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.

This patch replaces for_each_cpu with for_each_possible_cpu.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-29 13:44:15 +11:00
Eugene Surovegin
bab70a4af7 [PATCH] lock PTE before updating it in 440/BookE page fault handler
Fix 44x and BookE page fault handler to correctly lock PTE before
trying to pte_update() it, otherwise this PTE might be swapped out
after pte_present() check but before pte_uptdate() call, resulting in
corrupted PTE. This can happen with enabled preemption and low memory
condition.

Signed-off-by: Eugene Surovegin <ebs@ebshome.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-29 13:44:15 +11:00
Oleg Nesterov
a7e5328a06 [PATCH] cleanup __exit_signal->cleanup_sighand path
Move 'tsk->sighand = NULL' from cleanup_sighand() to __exit_signal().  This
makes the exit path more understandable and allows us to do
cleanup_sighand() outside of ->siglock protected section.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:44 -08:00
Oleg Nesterov
47e65328a7 [PATCH] pids: kill PIDTYPE_TGID
This patch kills PIDTYPE_TGID pid_type thus saving one hash table in
kernel/pid.c and speeding up subthreads create/destroy a bit.  It is also a
preparation for the further tref/pids rework.

This patch adds 'struct list_head thread_group' to 'struct task_struct'
instead.

We don't detach group leader from PIDTYPE_PID namespace until another
thread inherits it's ->pid == ->tgid, so we are safe wrt premature
free_pidmap(->tgid) call.

Currently there are no users of find_task_by_pid_type(PIDTYPE_TGID).
Should the need arise, we can use find_task_by_pid()->group_leader.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-By: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:44 -08:00
Oleg Nesterov
6a14c5c9da [PATCH] move __exit_signal() to kernel/exit.c
__exit_signal() is private to release_task() now.  I think it is better to
make it static in kernel/exit.c and export flush_sigqueue() instead - this
function is much more simple and straightforward.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:43 -08:00
Oleg Nesterov
c81addc9d3 [PATCH] rename __exit_sighand to cleanup_sighand
Cosmetic, rename __exit_sighand to cleanup_sighand and move it close to
copy_sighand().

This matches copy_signal/cleanup_signal naming, and I think it is easier to
follow.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:43 -08:00
Oleg Nesterov
6b3934ef52 [PATCH] copy_process: cleanup bad_fork_cleanup_signal
__exit_signal() does important cleanups atomically under ->siglock.  It is
also called from copy_process's error path.  This is not good, for example we
can't move __unhash_process() under ->siglock for that reason.

We should not mix these 2 paths, just look at ugly 'if (p->sighand)' under
'bad_fork_cleanup_sighand:' label.  For copy_process() case it is sufficient
to just backout copy_signal(), nothing more.

Again, nobody can see this task yet.  For CLONE_THREAD case we just decrement
signal->count, otherwise nobody can see this ->signal and we can free it
lockless.

This patch assumes it is safe to do exit_thread_group_keys() without
tasklist_lock.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:42 -08:00
Oleg Nesterov
7001510d0c [PATCH] copy_process: cleanup bad_fork_cleanup_sighand
The only caller of exit_sighand(tsk) is copy_process's error path.  We can
call __exit_sighand() directly and kill exit_sighand().

This 'tsk' was not yet registered in pid_hash[] or init_task.tasks, it has no
external references, nobody can see it, and

	IF (clone_flags & CLONE_SIGHAND)
		At least 'current' has a reference to ->sighand, this
		means atomic_dec_and_test(sighand->count) can't be true.

	ELSE
		Nobody can see this ->sighand, this means we can free it
		without any locking.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:42 -08:00
Oleg Nesterov
f63ee72e0f [PATCH] introduce lock_task_sighand() helper
Add lock_task_sighand() helper and converts group_send_sig_info() to use
it.  Hopefully we will have more users soon.

This patch also removes '!sighand->count' and '!p->usage' checks, I think
they both are bogus, racy and unneeded (but probably it makes sense to
restore them as BUG_ON()s).

->sighand is cleared and it's ->count is decremented in release_task() with
sighand->siglock held, so it is a bug to have '!p->usage || !->count' after
we already locked and verified it is the same.  On the other hand, an
already dead task without ->sighand can have a non-zero ->usage due to
ptrace, for example.

If we read the stale value of ->sighand we must see the change after
spin_lock(), because that change was done while holding that same old
->sighand.siglock.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:42 -08:00
Oleg Nesterov
aa1757f90b [PATCH] convert sighand_cache to use SLAB_DESTROY_BY_RCU
This patch borrows a clever Hugh's 'struct anon_vma' trick.

Without tasklist_lock held we can't trust task->sighand until we locked it
and re-checked that it is still the same.

But this means we don't need to defer 'kmem_cache_free(sighand)'.  We can
return the memory to slab immediately, all we need is to be sure that
sighand->siglock can't dissapear inside rcu protected section.

To do so we need to initialize ->siglock inside ctor function,
SLAB_DESTROY_BY_RCU does the rest.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:42 -08:00
Oleg Nesterov
c7c6464117 [PATCH] pidhash: don't use zero pids
daemonize() calls set_special_pids(1,1), while init and kernel threads spawned
from init/main.c:init() run with 0,0 special pids.  This patch changes
INIT_SIGNALS() so that that they run with ->pgrp == ->session == 1 also.  This
patch relies on fact that swapper's pid == 1.

Now we have no hashed zero pids in pid_hash[].

User-space visibible change is that now /sbin/init runs with (1,1) special
pids and becomes a session leader.

Quoting Eric W. Biederman:
>
> daemonize consuming pids (1,1) then consumes pgrp 1.  So that when
> /sbin/init calls setsid() it thinks /sbin/init is a process group
> leader and setsid() fails.  So /sbin/init wants pgrp 1 session 1
> but doesn't get it.  I am pretty certain daemonize did not exist so
> /sbin/init got pgrp 1 session 1 in 2.4.
>
> That is the bug that is being fixed.
>
> This patch takes things one step farther and essentially calls
> setsid() for pid == 1 before init is execed.  That is new behavior
> but it cleans up the kernel as we now do not need to support the
> case of a process without a process group or a session.
>
> The only process that could have possibly cared was /sbin/init
> and it already calls setsid() because it doesn't want that.
>
> If this was going to break anything noticeable the change in behavior
> from 2.4 to 2.6 would have already done that.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:41 -08:00
Oleg Nesterov
73b9ebfe12 [PATCH] pidhash: don't count idle threads
fork_idle() does unhash_process() just after copy_process().  Contrary,
boot_cpu's idle thread explicitely registers itself for each pid_type with nr
= 0.

copy_process() already checks p->pid != 0 before process_counts++, I think we
can just skip attach_pid() calls and job control inits for idle threads and
kill unhash_process().  We don't need to cleanup ->proc_dentry in fork_idle()
because with this patch idle threads are never hashed in
kernel/pid.c:pid_hash[].

We don't need to hash pid == 0 in pidmap_init().  free_pidmap() is never
called with pid == 0 arg, so it will never be reused.  So it is still possible
to use pid == 0 in any PIDTYPE_xxx namespace from kernel/pid.c's POV.

However with this patch we don't hash pid == 0 for PIDTYPE_PID case.  We still
have have PIDTYPE_PGID/PIDTYPE_SID entries with pid == 0: /sbin/init and
kernel threads which don't call daemonize().

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:41 -08:00
Oleg Nesterov
c97d98931a [PATCH] kill SET_LINKS/REMOVE_LINKS
Both SET_LINKS() and SET_LINKS/REMOVE_LINKS() have exactly one caller, and
these callers already check thread_group_leader().

This patch kills theese macros, they mix two different things: setting
process's parent and registering it in init_task.tasks list.  Callers are
updated to do these actions by hand.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:41 -08:00
Oleg Nesterov
8fafabd86f [PATCH] remove add_parent()'s parent argument
add_parent(p, parent) is always called with parent == p->parent, and it makes
no sense to do it differently.  This patch removes this argument.

No changes in affected .o files.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:41 -08:00
Eric W. Biederman
d73d65293e [PATCH] pidhash: kill switch_exec_pids
switch_exec_pids is only called from de_thread by way of exec, and it is
only called when we are exec'ing from a non thread group leader.

Currently switch_exec_pids gives the leader the pid of the thread and
unhashes and rehashes all of the process groups.  The leader is already in
the EXIT_DEAD state so no one cares about it's pids.  The only concern for
the leader is that __unhash_process called from release_task will function
correctly.  If we don't touch the leader at all we know that
__unhash_process will work fine so there is no need to touch the leader.

For the task becomming the thread group leader, we just need to give it the
pid of the old thread group leader, add it to the task list, and attach it
to the session and the process group of the thread group.

Currently de_thread is also adding the task to the task list which is just
silly.

Currently the only leader of __detach_pid besides detach_pid is
switch_exec_pids because of the ugly extra work that was being
performed.

So this patch removes switch_exec_pids because it is doing too much, it is
creating an unnecessary special case in pid.c, duing work duplicated in
de_thread, and generally obscuring what it is going on.

The necessary work is added to de_thread, and it seems to be a little
clearer there what is going on.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:40 -08:00
Eric W. Biederman
6c99c5cb94 [PATCH] Remove dead kill_sl prototype from sched.h
The kill_sl function doesn't exist in the kernel so a prototype is completely
unnecessary.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:40 -08:00