Commit Graph

125 Commits

Author SHA1 Message Date
Truxton Fulton
59f4e7d572 [PATCH] fix reboot via keyboard controller reset
I have a system (Biostar IDEQ210M mini-pc with a VIA chipset) which will
not reboot unless a keyboard is plugged in to it.  I have tried all
combinations of the kernel "reboot=x,y" flags to no avail.  Rebooting by
any method will leave the system in a wedged state (at the "Restarting
system" message).

I finally tracked the problem down to the machine's refusal to fully reboot
unless the keyboard controller status register had bit 2 set.  This is the
"System flag" which when set, indicates successful completion of the
keyboard controller self-test (Basic Assurance Test, BAT).

I suppose that something is trying to protect against sporadic reboots
unless the keyboard controller is in a good state (a keyboard is present),
but I need this machine to be headless.

I found that setting the system flag (via the command byte) before giving
the "pulse reset line" command will allow the reboot to proceed.  The patch
is simple, and I think it should be fine for everybody whether they have
this type of machine or not.  This affects the "hard" reboot (as done when
the kernel boot flags "reboot=c,h" are used).

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:57:35 -07:00
Magnus Damm
abda24528a [PATCH] i386: CONFIG_ACPI_SRAT typo fix
Fix a typo involving CONFIG_ACPI_SRAT.

Signed-off-by: Magnus Damm <magnus@valinux.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:56:44 -07:00
Len Brown
64e47488c9 Merge linux-2.6 with linux-acpi-2.6 2005-09-08 01:45:47 -04:00
Stephen Rothwell
8d286aa5ea [PATCH] Clean up struct flock64 definitions
This patch gathers all the struct flock64 definitions (and the operations),
puts them under !CONFIG_64BIT and cleans up the arch files.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:38 -07:00
Stephen Rothwell
5ac353f9ba [PATCH] Clean up struct flock definitions
This patch just gathers together all the struct flock definitions except
xtensa into asm-generic/fcntl.h.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:38 -07:00
Stephen Rothwell
1abf62afb6 [PATCH] Clean up the fcntl operations
This patch puts the most popular of each fcntl operation/flag into
asm-generic/fcntl.h and cleans up the arch files.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:38 -07:00
Stephen Rothwell
e64ca97fd8 [PATCH] Clean up the open flags
This patch puts the most popular of each open flag into asm-generic/fcntl.h
and cleans up the arch files.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:38 -07:00
Stephen Rothwell
9317259ead [PATCH] Create asm-generic/fcntl.h
This set of patches creates asm-generic/fcntl.h and consolidates as much as
possible from the asm-*/fcntl.h files into it.

This patch just gathers all the identical bits of the asm-*/fcntl.h files into
asm-generic/fcntl.h.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:37 -07:00
Jesper Juhl
97de50c0ad [PATCH] remove verify_area(): remove verify_area() from various uaccess.h headers
Remove the deprecated (and unused) verify_area() from various uaccess.h
headers.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:35 -07:00
Christoph Hellwig
c8d127418d [PATCH] remove asm-*/hdreg.h
unused and useless..

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:30 -07:00
H. J. Lu
36d57ac4a8 [PATCH] auxiliary vector cleanups
The size of auxiliary vector is fixed at 42 in linux/sched.h.  But it isn't
very obvious when looking at linux/elf.h.  This patch adds AT_VECTOR_SIZE
so that we can change it if necessary when a new vector is added.

Because of include file ordering problems, doing this necessitated the
extraction of the AT_* symbols into a standalone header file.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:21 -07:00
Jakub Jelinek
4732efbeb9 [PATCH] FUTEX_WAKE_OP: pthread_cond_signal() speedup
ATM pthread_cond_signal is unnecessarily slow, because it wakes one waiter
(which at least on UP usually means an immediate context switch to one of
the waiter threads).  This waiter wakes up and after a few instructions it
attempts to acquire the cv internal lock, but that lock is still held by
the thread calling pthread_cond_signal.  So it goes to sleep and eventually
the signalling thread is scheduled in, unlocks the internal lock and wakes
the waiter again.

Now, before 2003-09-21 NPTL was using FUTEX_REQUEUE in pthread_cond_signal
to avoid this performance issue, but it was removed when locks were
redesigned to the 3 state scheme (unlocked, locked uncontended, locked
contended).

Following scenario shows why simply using FUTEX_REQUEUE in
pthread_cond_signal together with using lll_mutex_unlock_force in place of
lll_mutex_unlock is not enough and probably why it has been disabled at
that time:

The number is value in cv->__data.__lock.
        thr1            thr2            thr3
0       pthread_cond_wait
1       lll_mutex_lock (cv->__data.__lock)
0       lll_mutex_unlock (cv->__data.__lock)
0       lll_futex_wait (&cv->__data.__futex, futexval)
0                       pthread_cond_signal
1                       lll_mutex_lock (cv->__data.__lock)
1                                       pthread_cond_signal
2                                       lll_mutex_lock (cv->__data.__lock)
2                                         lll_futex_wait (&cv->__data.__lock, 2)
2                       lll_futex_requeue (&cv->__data.__futex, 0, 1, &cv->__data.__lock)
                          # FUTEX_REQUEUE, not FUTEX_CMP_REQUEUE
2                       lll_mutex_unlock_force (cv->__data.__lock)
0                         cv->__data.__lock = 0
0                         lll_futex_wake (&cv->__data.__lock, 1)
1       lll_mutex_lock (cv->__data.__lock)
0       lll_mutex_unlock (cv->__data.__lock)
          # Here, lll_mutex_unlock doesn't know there are threads waiting
          # on the internal cv's lock

Now, I believe it is possible to use FUTEX_REQUEUE in pthread_cond_signal,
but it will cost us not one, but 2 extra syscalls and, what's worse, one of
these extra syscalls will be done for every single waiting loop in
pthread_cond_*wait.

We would need to use lll_mutex_unlock_force in pthread_cond_signal after
requeue and lll_mutex_cond_lock in pthread_cond_*wait after lll_futex_wait.

Another alternative is to do the unlocking pthread_cond_signal needs to do
(the lock can't be unlocked before lll_futex_wake, as that is racy) in the
kernel.

I have implemented both variants, futex-requeue-glibc.patch is the first
one and futex-wake_op{,-glibc}.patch is the unlocking inside of the kernel.
 The kernel interface allows userland to specify how exactly an unlocking
operation should look like (some atomic arithmetic operation with optional
constant argument and comparison of the previous futex value with another
constant).

It has been implemented just for ppc*, x86_64 and i?86, for other
architectures I'm including just a stub header which can be used as a
starting point by maintainers to write support for their arches and ATM
will just return -ENOSYS for FUTEX_WAKE_OP.  The requeue patch has been
(lightly) tested just on x86_64, the wake_op patch on ppc64 kernel running
32-bit and 64-bit NPTL and x86_64 kernel running 32-bit and 64-bit NPTL.

With the following benchmark on UP x86-64 I get:

for i in nptl-orig nptl-requeue nptl-wake_op; do echo time elf/ld.so --library-path .:$i /tmp/bench; \
for j in 1 2; do echo ( time elf/ld.so --library-path .:$i /tmp/bench ) 2>&1; done; done
time elf/ld.so --library-path .:nptl-orig /tmp/bench
real 0m0.655s user 0m0.253s sys 0m0.403s
real 0m0.657s user 0m0.269s sys 0m0.388s
time elf/ld.so --library-path .:nptl-requeue /tmp/bench
real 0m0.496s user 0m0.225s sys 0m0.271s
real 0m0.531s user 0m0.242s sys 0m0.288s
time elf/ld.so --library-path .:nptl-wake_op /tmp/bench
real 0m0.380s user 0m0.176s sys 0m0.204s
real 0m0.382s user 0m0.175s sys 0m0.207s

The benchmark is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00001.txt
Older futex-requeue-glibc.patch version is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00002.txt
Older futex-wake_op-glibc.patch version is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00003.txt
Will post a new version (just x86-64 fixes so that the patch
applies against pthread_cond_signal.S) to libc-hacker ml soon.

Attached is the kernel FUTEX_WAKE_OP patch as well as a simple-minded
testcase that will not test the atomicity of the operation, but at least
check if the threads that should have been woken up are woken up and
whether the arithmetic operation in the kernel gave the expected results.

Acked-by: Ingo Molnar <mingo@redhat.com>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Jamie Lokier <jamie@shareable.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:17 -07:00
Laurent Vivier
ed75e8d580 [PATCH] UML Support - Ptrace: adds the host SYSEMU support, for UML and general usage
Jeff Dike <jdike@addtoit.com>,
      Paolo 'Blaisorblade' Giarrusso <blaisorblade_spam@yahoo.it>,
      Bodo Stroesser <bstroesser@fujitsu-siemens.com>

Adds a new ptrace(2) mode, called PTRACE_SYSEMU, resembling PTRACE_SYSCALL
except that the kernel does not execute the requested syscall; this is useful
to improve performance for virtual environments, like UML, which want to run
the syscall on their own.

In fact, using PTRACE_SYSCALL means stopping child execution twice, on entry
and on exit, and each time you also have two context switches; with SYSEMU you
avoid the 2nd stop and so save two context switches per syscall.

Also, some architectures don't have support in the host for changing the
syscall number via ptrace(), which is currently needed to skip syscall
execution (UML turns any syscall into getpid() to avoid it being executed on
the host).  Fixing that is hard, while SYSEMU is easier to implement.

* This version of the patch includes some suggestions of Jeff Dike to avoid
  adding any instructions to the syscall fast path, plus some other little
  changes, by myself, to make it work even when the syscall is executed with
  SYSENTER (but I'm unsure about them). It has been widely tested for quite a
  lot of time.

* Various fixed were included to handle the various switches between
  various states, i.e. when for instance a syscall entry is traced with one of
  PT_SYSCALL / _SYSEMU / _SINGLESTEP and another one is used on exit.
  Basically, this is done by remembering which one of them was used even after
  the call to ptrace_notify().

* We're combining TIF_SYSCALL_EMU with TIF_SYSCALL_TRACE or TIF_SINGLESTEP
  to make do_syscall_trace() notice that the current syscall was started with
  SYSEMU on entry, so that no notification ought to be done in the exit path;
  this is a bit of a hack, so this problem is solved in another way in next
  patches.

* Also, the effects of the patch:
"Ptrace - i386: fix Syscall Audit interaction with singlestep"
are cancelled; they are restored back in the last patch of this series.

Detailed descriptions of the patches doing this kind of processing follow (but
I've already summed everything up).

* Fix behaviour when changing interception kind #1.

  In do_syscall_trace(), we check the status of the TIF_SYSCALL_EMU flag
  only after doing the debugger notification; but the debugger might have
  changed the status of this flag because he continued execution with
  PTRACE_SYSCALL, so this is wrong.  This patch fixes it by saving the flag
  status before calling ptrace_notify().

* Fix behaviour when changing interception kind #2:
  avoid intercepting syscall on return when using SYSCALL again.

  A guest process switching from using PTRACE_SYSEMU to PTRACE_SYSCALL
  crashes.

  The problem is in arch/i386/kernel/entry.S.  The current SYSEMU patch
  inhibits the syscall-handler to be called, but does not prevent
  do_syscall_trace() to be called after this for syscall completion
  interception.

  The appended patch fixes this.  It reuses the flag TIF_SYSCALL_EMU to
  remember "we come from PTRACE_SYSEMU and now are in PTRACE_SYSCALL", since
  the flag is unused in the depicted situation.

* Fix behaviour when changing interception kind #3:
  avoid intercepting syscall on return when using SINGLESTEP.

  When testing 2.6.9 and the skas3.v6 patch, with my latest patch and had
  problems with singlestepping on UML in SKAS with SYSEMU.  It looped
  receiving SIGTRAPs without moving forward.  EIP of the traced process was
  the same for all SIGTRAPs.

What's missing is to handle switching from PTRACE_SYSCALL_EMU to
PTRACE_SINGLESTEP in a way very similar to what is done for the change from
PTRACE_SYSCALL_EMU to PTRACE_SYSCALL_TRACE.

I.e., after calling ptrace(PTRACE_SYSEMU), on the return path, the debugger is
notified and then wake ups the process; the syscall is executed (or skipped,
when do_syscall_trace() returns 0, i.e.  when using PTRACE_SYSEMU), and
do_syscall_trace() is called again.  Since we are on the return path of a
SYSEMU'd syscall, if the wake up is performed through ptrace(PTRACE_SYSCALL),
we must still avoid notifying the parent of the syscall exit.  Now, this
behaviour is extended even to resuming with PTRACE_SINGLESTEP.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:20 -07:00
Shaohua Li
c3c433e4f3 [PATCH] add suspend/resume for timer
The timers lack .suspend/.resume methods.  Because of this, jiffies got a
big compensation after a S3 resume.  And then softlockup watchdog reports
an oops.  This occured with HPET enabled, but it's also possible for other
timers.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:18 -07:00
Zwane Mwaikambo
4ad8d38342 [PATCH] i386 boottime for_each_cpu broken
for_each_cpu walks through all processors in cpu_possible_map, which is
defined as cpu_callout_map on i386 and isn't initialised until all
processors have been booted. This breaks things which do for_each_cpu
iterations early during boot. So, define cpu_possible_map as a bitmap with
NR_CPUS bits populated. This was triggered by a patch i'm working on which
does alloc_percpu before bringing up secondary processors.

From: Alexander Nyberg <alexn@telia.com>

i386-boottime-for_each_cpu-broken.patch
i386-boottime-for_each_cpu-broken-fix.patch

The SMP version of __alloc_percpu checks the cpu_possible_map before
allocating memory for a certain cpu.  With the above patches the BSP cpuid
is never set in cpu_possible_map which breaks CONFIG_SMP on uniprocessor
machines (as soon as someone tries to dereference something allocated via
__alloc_percpu, which in fact is never allocated since the cpu is not set
in cpu_possible_map).

Signed-off-by: Zwane Mwaikambo <zwane@arm.linux.org.uk>
Signed-off-by: Alexander Nyberg <alexn@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:13 -07:00
Zachary Amsden
d7271b14b2 [PATCH] i386: encapsulate copying of pgd entries
Add a clone operation for pgd updates.

This helps complete the encapsulation of updates to page tables (or pages
about to become page tables) into accessor functions rather than using
memcpy() to duplicate them.  This is both generally good for consistency
and also necessary for running in a hypervisor which requires explicit
updates to page table entries.

The new function is:

clone_pgd_range(pgd_t *dst, pgd_t *src, int count);

   dst - pointer to pgd range anwhere on a pgd page
   src - ""
   count - the number of pgds to copy.

   dst and src can be on the same page, but the range must not overlap
   and must not cross a page boundary.

Note that I ommitted using this call to copy pgd entries into the
software suspend page root, since this is not technically a live paging
structure, rather it is used on resume from suspend.  CC'ing Pavel in case
he has any feedback on this.

Thanks to Chris Wright for noticing that this could be more optimal in
PAE compiles by eliminating the memset.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:13 -07:00
George Anzinger
748f2edb52 [PATCH] x86 NMI: better support for debuggers
This patch adds a notify to the die_nmi notify that the system is about to
be taken down.  If the notify is handled with a NOTIFY_STOP return, the
system is given a new lease on life.

We also change the nmi watchdog to carry on if die_nmi returns.

This give debug code a chance to a) catch watchdog timeouts and b) possibly
allow the system to continue, realizing that the time out may be due to
debugger activities such as single stepping which is usually done with
"other" cpus held.

Signed-off-by: George Anzinger<george@mvista.com>
Cc: Keith Owens <kaos@ocs.com.au>
Signed-off-by: George Anzinger <george@mvista.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:13 -07:00
Zachary Amsden
f2f30ebca6 [PATCH] x86: introduce a write acessor for updating the current LDT
Introduce a write acessor for updating the current LDT.  This is required
for hypervisors like Xen that do not allow LDT pages to be directly
written.

Testing - here's a fun little LDT test that can be trivially modified to
test limits as well.

/*
 * Copyright (c) 2005, Zachary Amsden (zach@vmware.com)
 * This is licensed under the GPL.
 */

#include <stdio.h>
#include <signal.h>
#include <asm/ldt.h>
#include <asm/segment.h>
#include <sys/types.h>
#include <unistd.h>
#include <sys/mman.h>
#define __KERNEL__
#include <asm/page.h>

void main(void)
{
        struct user_desc desc;
        char *code;
        unsigned long long tsc;

        code = (char *)mmap(0, 8192, PROT_EXEC|PROT_READ|PROT_WRITE,
                                 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
        desc.entry_number = 0;
        desc.base_addr = code;
        desc.limit = 1;
        desc.seg_32bit = 1;
        desc.contents = MODIFY_LDT_CONTENTS_CODE;
        desc.read_exec_only = 0;
        desc.limit_in_pages = 1;
        desc.seg_not_present = 0;
        desc.useable = 1;
        if (modify_ldt(1, &desc, sizeof(desc)) != 0) {
                perror("modify_ldt");
        }
        printf("code base is 0x%08x\n", (unsigned)code);
        code[0x0ffe] = 0x0f;  /* rdtsc */
        code[0x0fff] = 0x31;
        code[0x1000] = 0xcb;  /* lret */
        __asm__ __volatile("lcall $7,$0xffe" : "=A" (tsc));
        printf("TSC is 0x%016llx\n", tsc);
}

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:13 -07:00
Zachary Amsden
a520112930 [PATCH] x86: make IOPL explicit
The pushf/popf in switch_to are ONLY used to switch IOPL.  Making this
explicit in C code is more clear.  This pushf/popf pair was added as a
bugfix for leaking IOPL to unprivileged processes when using
sysenter/sysexit based system calls (sysexit does not restore flags).

When requesting an IOPL change in sys_iopl(), it is just as easy to change
the current flags and the flags in the stack image (in case an IRET is
required), but there is no reason to force an IRET if we came in from the
SYSENTER path.

This change is the minimal solution for supporting a paravirtualized Linux
kernel that allows user processes to run with I/O privilege.  Other
solutions require radical rewrites of part of the low level fault / system
call handling code, or do not fully support sysenter based system calls.

Unfortunately, this added one field to the thread_struct.  But as a bonus,
on P4, the fastest time measured for switch_to() went from 312 to 260
cycles, a win of about 17% in the fast case through this performance
critical path.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:12 -07:00
Zachary Amsden
0998e4228a [PATCH] x86: privilege cleanup
Privilege checking cleanup.  Originally, these diffs were much greater, but
recent cleanups in Linux have already done much of the cleanup.  I added
some explanatory comments in places where the reasoning behind certain
tests is rather subtle.

Also, in traps.c, we can skip the user_mode check in handle_BUG().  The
reason is, there are only two call chains - one via die_if_kernel() and one
via do_page_fault(), both entering from die().  Both of these paths already
ensure that a kernel mode failure has happened.  Also, the original check
here, if (user_mode(regs)) was insufficient anyways, since it would not
rule out BUG faults from V8086 mode execution.

Saving the %ss segment in show_regs() rather than assuming a fixed value
also gives better information about the current kernel state in the
register dump.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:12 -07:00
Zachary Amsden
f2ab446124 [PATCH] x86: more asm cleanups
Some more assembler cleanups I noticed along the way.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:12 -07:00
Ingo Molnar
4f0cb8d978 [PATCH] i386: fix incorrect TSS entry for LDT
Noticed by Chuck Ebbert: the .ldt entry of the TSS was set up incorrectly.
It never mattered since this was a leftover from old times, so remove it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:12 -07:00
Zachary Amsden
c9b02a2413 [PATCH] i386: use set_pte macros in a couple places where they were missing
Also, setting PDPEs in PAE mode does not require atomic operations, since the
PDPEs are cached by the processor, and only reloaded on an explicit or
implicit reload of CR3.

Since the four PDPEs must always be present in an active root, and the kernel
PDPE is never updated, we are safe even from SMIs and interrupts / NMIs using
task gates (which reload CR3).  Actually, much of this is moot, since the user
PDPEs are never updated either, and the only usage of task gates is by the
doublefault handler.  It appears the only place PGDs get updated in PAE mode
is in init_low_mappings() / zap_low_mapping() for initial page table creation
and recovery from ACPI sleep state, and these sites are safe by inspection.
Getting rid of the cmpxchg8b saves code space and 720 cycles in pgd_alloc on
P4.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:12 -07:00
Zachary Amsden
2f2984eb4a [PATCH] i386: generate better code around descriptor update and access functions
GCC can generate better code around descriptor update and access functions
when there is not an explicit "eax" register constraint.

Testing: You won't boot if this is messed up, since the TSS descriptor will be
corrupted.  Verified the assembler and booted.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:11 -07:00
Zachary Amsden
4d37e7e3fd [PATCH] i386: inline assembler: cleanup and encapsulate descriptor and task register management
i386 inline assembler cleanup.

This change encapsulates descriptor and task register management.  Also,
it is possible to improve assembler generation in two cases; savesegment
may store the value in a register instead of a memory location, which
allows GCC to optimize stack variables into registers, and MOV MEM, SEG
is always a 16-bit write to memory, making the casting in math-emu
unnecessary.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:11 -07:00
Zachary Amsden
245067d167 [PATCH] i386: cleanup serialize msr
i386 arch cleanup.  Introduce the serialize macro to serialize processor
state.  Why the microcode update needs it I am not quite sure, since wrmsr()
is already a serializing instruction, but it is a microcode update, so I will
keep the semantic the same, since this could be a timing workaround.  As far
as I can tell, this has always been there since the original microcode update
source.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:11 -07:00
Zachary Amsden
4bb0d3ec3e [PATCH] i386: inline asm cleanup
i386 Inline asm cleanup.  Use cr/dr accessor functions.

Also, a potential bugfix.  Also, some CR accessors really should be volatile.
Reads from CR0 (numeric state may change in an exception handler), writes to
CR4 (flipping CR4.TSD) and reads from CR2 (page fault) prevent instruction
re-ordering.  I did not add memory clobber to CR3 / CR4 / CR0 updates, as it
was not there to begin with, and in no case should kernel memory be clobbered,
except when doing a TLB flush, which already has memory clobber.

I noticed that page invalidation does not have a memory clobber.  I can't find
a bug as a result, but there is definitely a potential for a bug here:

#define __flush_tlb_single(addr) \
	__asm__ __volatile__("invlpg %0": :"m" (*(char *) addr))

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:11 -07:00
Natalie.Protasevich@unisys.com
56f1d5d52a [PATCH] ES7000 platform update (i386)
This is subarch update for ES7000.  I've modified platform check code and
removed unnecessary OEM table parsing for newer systems that don't use OEM
information during boot.  Parsing the table in fact is causing problems,
and the platform doesn't get recognized.  The patch only affects the ES7000
subach.

Signed-off-by: <Natalie.Protasevich@unisys.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:10 -07:00
Venkatesh Pallipadi
911a62d423 [PATCH] x86: sutomatically enable bigsmp when we have more than 8 CPUs
i386 generic subarchitecture requires explicit dmi strings or command line
to enable bigsmp mode.  The patch below removes that restriction, and uses
bigsmp as soon as it finds more than 8 logical CPUs, Intel processors and
xAPIC support.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:10 -07:00
Matt Tolentino
7ae65fd334 [PATCH] x86: fix EFI memory map parsing
The memory descriptors that comprise the EFI memory map are not fixed in
stone such that the size could change in the future.  This uses the memory
descriptor size obtained from EFI to iterate over the memory map entries
during boot.  This enables the removal of an x86 specific pad (and ifdef)
in the EFI header.  I also couldn't stomach the broken up nature of the
function to put EFI runtime calls into virtual mode any longer so I fixed
that up a bit as well.

For reference, this patch only impacts x86.

Signed-off-by: Matt Tolentino <matthew.e.tolentino@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:09 -07:00
Zachary Amsden
a600388d28 [PATCH] x86: ptep_clear optimization
Add a new accessor for PTEs, which passes the full hint from the mmu_gather
struct; this allows architectures with hardware pagetables to optimize away
atomic PTE operations when destroying an address space.  Removing the
locked operation should allow better pipelining of memory access in this
loop.  I measured an average savings of 30-35 cycles per zap_pte_range on
the first 500 destructions on Pentium-M, but I believe the optimization
would win more on older processors which still assert the bus lock on xchg
for an exclusive cacheline.

Update: I made some new measurements, and this saves exactly 26 cycles over
ptep_get_and_clear on Pentium M.  On P4, with a PAE kernel, this saves 180
cycles per ptep_get_and_clear, for a whopping 92160 cycles savings for a
full address space destruction.

pte_clear_full is not yet used, but is provided for future optimizations
(in particular, when running inside of a hypervisor that queues page table
updates, the full hint allows us to avoid queueing unnecessary page table
update for an address space in the process of being destroyed.

This is not a huge win, but it does help a bit, and sets the stage for
further hypervisor optimization of the mm layer on all architectures.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Cc: Christoph Lameter <christoph@lameter.com>
Cc: <linux-mm@kvack.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:05:48 -07:00
Kyle Moffett
fa5b08d5f8 [PATCH] sab: consolidate kmem_bufctl_t
This is used only in slab.c and each architecture gets to define whcih
underlying type is to be used.

Seems a bit silly - move it to slab.c and use the same type for all
architectures: unsigned int.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:05:48 -07:00
Chen, Kenneth W
0e5c9f39f6 [PATCH] remove hugetlb_clean_stale_pgtable() and fix huge_pte_alloc()
I don't think we need to call hugetlb_clean_stale_pgtable() anymore
in 2.6.13 because of the rework with free_pgtables().  It now collect
all the pte page at the time of munmap.  It used to only collect page
table pages when entire one pgd can be freed and left with staled pte
pages.  Not anymore with 2.6.13.  This function will never be called
and We should turn it into a BUG_ON.

I also spotted two problems here, not Adam's fault :-)
(1) in huge_pte_alloc(), it looks like a bug to me that pud is not
    checked before calling pmd_alloc()
(2) in hugetlb_clean_stale_pgtable(), it also missed a call to
    pmd_free_tlb.  I think a tlb flush is required to flush the mapping
    for the page table itself when we clear out the pmd pointing to a
    pte page.  However, since hugetlb_clean_stale_pgtable() is never
    called, so it won't trigger the bug.

Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Cc: Adam Litke <agl@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:05:46 -07:00
Adam Litke
32e51a8c97 [PATCH] hugetlb: add pte_huge() macro
This patch adds a macro pte_huge(pte) for i386/x86_64 which is needed by a
patch later in the series.  Instead of repeating (_PAGE_PRESENT |
_PAGE_PSE), I've added __LARGE_PTE to i386 to match x86_64.

Signed-off-by: Adam Litke <agl@us.ibm.com>
Cc: <linux-mm@kvack.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:05:46 -07:00
Paolo 'Blaisorblade' Giarrusso
9b4ee40ebb [PATCH] mm: correct _PAGE_FILE comment
_PAGE_FILE does not indicate whether a file is in page / swap cache, it is
set just for non-linear PTE's.  Correct the comment for i386, x86_64, UML.
Also clearify _PAGE_NONE.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:05:45 -07:00
Stephen Rothwell
fd4fd5aac1 [PATCH] mm: consolidate get_order
Someone mentioned that almost all the architectures used basically the same
implementation of get_order.  This patch consolidates them into
asm-generic/page.h and includes that in the appropriate places.  The
exceptions are ia64 and ppc which have their own (presumably optimised)
versions.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:05:39 -07:00
Len Brown
129521dcc9 Merge linux-2.6 into linux-acpi-2.6 test 2005-09-03 02:44:09 -04:00
Thomas Graf
2c656491e9 [NET]: Fix ipl=>ihl typo in ip_fast_csum
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 16:02:48 -07:00
Patrick McHardy
b0573dea1f [NET]: Introduce SO_{SND,RCV}BUFFORCE socket options
Allows overriding of sysctl_{wmem,rmrm}_max

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 15:31:35 -07:00
Len Brown
6153df7b2f [ACPI] delete CONFIG_ACPI_PCI
Delete the ability to build an ACPI kernel that does
not include PCI support.  When such a machine is created
and it requires a tuned kernel, send a patch.

http://bugzilla.kernel.org/show_bug.cgi?id=1364

Signed-off-by: Len Brown <len.brown@intel.com>
2005-08-25 12:40:44 -04:00
Len Brown
888ba6c62b [ACPI] delete CONFIG_ACPI_BOOT
it has been a synonym for CONFIG_ACPI since 2.6.12

Signed-off-by: Len Brown <len.brown@intel.com>
2005-08-24 12:08:54 -04:00
Zachary Amsden
12aaa0855b [PATCH] i386 / desc_empty macro is incorrect
Chuck Ebbert noticed that the desc_empty macro is incorrect.  Fix it.

Thankfully, this is not used as a security check, but it can falsely
overwrite TLS segments with carefully chosen base / limits.  I do not
believe this is an issue in practice, but it is a kernel bug.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Chris Wright <chrisw@osdl.org>

[ x86-64 had the same problem, and the same fix. Linus ]

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-16 12:18:01 -07:00
Linus Torvalds
2ba84684e8 Revert PCIBIOS_MIN_IO changes for 2.6.13
This reverts commits

  71db63acff
	[PATCH] increase PCIBIOS_MIN_IO on x86

and

  0b2bfb4e7f
    ACPI: increase PCIBIOS_MIN_IO on x86

since Lukas Sandströ<lukass@etek.chalmers.se> reports that this breaks
his on-board nvidia audio.

We should re-visit this later. For now we revert the change

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-14 18:21:30 -07:00
Tom Duffy
6c79d7260a [PATCH] Make visws compile again
In file included from linux-2.6.13-rc5/arch/i386/kernel/timers/timer_pit.c:20:
linux-2.6.13-rc5/include/asm-i386/mach-visws/do_timer.h: In function `do_timer_overflow':
linux-2.6.13-rc5/include/asm-i386/mach-visws/do_timer.h:32: error: `i8259A_lock' undeclared (first use in this function)
linux-2.6.13-rc5/include/asm-i386/mach-visws/do_timer.h:32: error: (Each undeclared identifier is reported only once
linux-2.6.13-rc5/include/asm-i386/mach-visws/do_timer.h:32: error: for each function it appears in.)
make[3]: *** [arch/i386/kernel/timers/timer_pit.o] Error 1
make[2]: *** [arch/i386/kernel/timers] Error 2
make[1]: *** [arch/i386/kernel] Error 2
make: *** [_all] Error 2

Signed-off-by: Tom Duffy <thomas.duffy.99@alumni.brown.edu>
Cc: Andrey Panin <pazke@orbita1.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-07 10:00:38 -07:00
Ivan Kokshaysky
71db63acff [PATCH] increase PCIBIOS_MIN_IO on x86
There is a number of x86 laptops that have some non-PCI IO ports
in the 0x1000-0x1fff range, and it's quite hard to control the correct
order of resource allocation between PCI and other subsystems controlling
these ports. Especially with modular kernel.

So just increase PCIBIOS_MIN_IO to 0x4000 to prevent any new PCI
resource allocations in the problematic range (this limitation must
apply _only_ to the root bus resources - see Linus' change in
pci_bus_alloc_resource).  As PCIBIOS_MIN_IO and PCIBIOS_MIN_CARDBUS_IO
are the same now on i386 and x86-64, we can remove the latter.

Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-02 18:21:25 -07:00
Linus Torvalds
d6d2a2ab05 x86: fix new find_first_bit()
Some edge problems with the original C rewrite.

Thanks go to Cal Peake, who pinpointed the breakage to the rewrite, and
tested this fixed version.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-29 11:01:22 -04:00
Andi Kleen
5b943fbfaf [PATCH] x86_64: i386/x86_64: remove prototypes for not existing functions in smp.h
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-28 21:45:58 -07:00
Steven Rostedt
cd85c8b445 [PATCH] speed up on find_first_bit for i386 (let compiler do the work)
Avoid using "rep scas", just let the compiler select a sequence of
regular instructions.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-28 08:40:31 -07:00
Andrew Morton
388b0925f5 [PATCH] user_mode_vm() build fix
include/asm/ptrace.h: In function `user_mode_vm':
include/asm/ptrace.h:67: `VM_MASK' undeclared (first use in this function)

Cc: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:25:47 -07:00
Chuck Ebbert
ae6578fe9b [PATCH] i386: clean up user_mode macros
- make the new user_mode() return 0 or 1 (same as x86_64)

 - remove conditional jump from user_mode_vm() it's called every timer
   tick on each CPU on SMP)

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-26 19:25:01 -07:00