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>
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>
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>
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>
Subtle fix: load_TLS has been moved after saving %fs and %gs segments to avoid
creating non-reversible segments. This could conceivably cause a bug if the
kernel ever needed to save and restore fs/gs from the NMI handler. It
currently does not, but this is the safest approach to avoiding fs/gs
corruption. SMIs are safe, since SMI saves the descriptor hidden state.
Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
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>
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>
This makes the vDSO use nops for all its padding around instructions,
rather than sometimes zeros, and nop-pads the end of the area containing
instructions to a 32-byte cache line, to keep text and data in separate
lines.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
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>
o With introduction of kexec as boot-loader, the assumption that parameter
segment will always be loaded at lower address than kernel and will be
addressable by early bootup page tables is no longer valid. In kexec on
panic case parameter segment might well be loaded beyond kernel image and
might not be addressable by early boot page tables.
o This case might hit in the scenario where user has reserved a chunk of
memory for second kernel, for example 16MB to 64MB, and has also built
second kernel for physical memory location 16MB. In this case kexec has no
choice but to load the parameter segment at a higher address than new kernel
image at safe location where new kernel does not stomp it.
o Though problem should automatically go away once relocatable kernel for i386
is in place and kexec can determine the location of new kernel at run time
and load parameter segment at lower address than kernel image. But till then
this patch can go in (assuming it does not break something else).
o This patch moves up the boot parameter saving code. Now boot parameters
are copied out in protected mode before page tables are initialized. This
will ensure that parameter segment is always addressable irrespective of
its physical location.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If the virtual 86 machine reaches an instruction which raises a General
Protection Fault (such as CLI or STI), the instruction is emulated (in
handle_vm86_fault). However, the emulation ignored the TF bit, so the
hardware debug interrupt was not invoked after such an emulated instruction
(and the DOS debugger missed it).
This patch fixes the problem by emulating the hardware debug interrupt as
the last action before control is returned to the VM86 program.
Signed-off-by: Petr Tesarik <kernel@tesarici.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
Only use read_timer_tsc only when CPU has TSC. Thanks to Andrea for
pointing this out. Should not be issue on any platforms as all recent
systems that has HPET also has CPUs that supports TSC. The patch is still
required for correctness.
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>
This patch pushes the creation of a rare signal frame (SIGBUS or SIGSEGV)
into a separate function, thus saving stackspace in the main
do_page_fault() stackframe. The effect is 132 bytes less of stack used by
the typical do_page_fault() invocation - resulting in a denser
cache-layout.
(Another minor effect is that in case of kernel crashes that come from a
pagefault, we add less space to the already existing frame, giving the
crash functions a slightly higher chance to do their stuff without
overflowing the stack.)
(The changes also result in slightly cleaner code.)
argument bugfix from "Guillaume C." <guichaz@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
For demand faulting, we cannot assume that the page tables will be
populated. Do what the rest of the architectures do and test p?d_present()
while walking down the page table.
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>
Initial Post (Wed, 17 Aug 2005)
This patch moves the
if (! pte_none(*pte))
hugetlb_clean_stale_pgtable(pte);
logic into huge_pte_alloc() so all of its callers can be immune to the bug
described by Kenneth Chen at http://lkml.org/lkml/2004/6/16/246
> It turns out there is a bug in hugetlb_prefault(): with 3 level page table,
> huge_pte_alloc() might return a pmd that points to a PTE page. It happens
> if the virtual address for hugetlb mmap is recycled from previously used
> normal page mmap. free_pgtables() might not scrub the pmd entry on
> munmap and hugetlb_prefault skips on any pmd presence regardless what type
> it is.
Unless I am missing something, it seems more correct to place the check inside
huge_pte_alloc() to prevent a the same bug wherever a huge pte is allocated.
It also allows checking for this condition when lazily faulting huge pages
later in the series.
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>
With cleanups from Dave Hansen <haveblue@us.ibm.com>
SPARSEMEM_EXTREME makes mem_section a one dimensional array of pointers to
mem_sections. This two level layout scheme is able to achieve smaller
memory requirements for SPARSEMEM with the tradeoff of an additional shift
and load when fetching the memory section. The current SPARSEMEM
implementation is a one dimensional array of mem_sections which is the
default SPARSEMEM configuration. The patch attempts isolates the
implementation details of the physical layout of the sparsemem section
array.
SPARSEMEM_EXTREME requires bootmem to be functioning at the time of
memory_present() calls. This is not always feasible, so architectures
which do not need it may allocate everything statically by using
SPARSEMEM_STATIC.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Minor fallout from my upcoming __attribute__((format(printf,x,y)))
patches. The variable 'result' is untouched, so this patch just removes
it.
Signed-off-by: Mika Kukkonen <mikukkon@gmail.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Ho-hum, did not notice there was more printf fixes for cpufreq (you
should see the amount I have for isdn and reiser ...). Sorry for noise.
Signed-off-by: Mika Kukkonen <mikukkon@gmail.com>
Signed-off-by: Dave Jones <davej@redhat.com>
speedstep_centrino.c:extract_clock() assumes the bus speed of 100MHz, which is
not true with latest laptops. Due to this assumption and due to the encoded
frequency check during initialization, speedstep-centrino driver fails even
on systems that has proper ACPI information to do the P-state transition.
The change below moves the centrino-speedstep detection to be used only
when table based P-state transition is done. For ACPI based P-state
transition, we skip the centrino_cpu identification, and as a result we
don't use the bus speed assumption in extract_clock. This change makes
speedstep-centrino work on Pentium-M based systems, which have more than 100MHz
bus speed.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
I had some time to think about PCI assign issues in 2.6.13-rc series.
The major problem here is that we call pci_assign_unassigned_resources()
way too early - at subsys_initcall level. Therefore we give no chances
to ACPI and PnP routines (called at fs_initcall level) to reserve their
respective resources properly, as the comments in drivers/pnp/system.c
and drivers/acpi/motherboard.c suggest:
/**
* Reserve motherboard resources after PCI claim BARs,
* but before PCI assign resources for uninitialized PCI devices
*/
So I moved the pci_assign_unassigned_resources() call to
pcibios_assign_resources() (fs_initcall), which should hopefully fix a
lot of problems and make PCIBIOS_MIN_IO tweaks unnecessary.
Other changes:
- remove resource assignment code from pcibios_assign_resources(), since
it duplicates pci_assign_unassigned_resources() functionality and
actually does nothing in 2.6.13;
- modify ROM assignment code as per Ben's suggestion: try to use firmware
settings by default (if PCI_ASSIGN_ROMS is not set);
- set CARDBUS_IO_SIZE back to 4K as it's a wonderful stress test for
various setups.
Confirmed by Tero Roponen <teanropo@cc.jyu.fi> (who had problems with
the 4kB CardBus IO size previously).
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It has been reported that the way Linux handles NODEFER for signals is
not consistent with the way other Unix boxes handle it. I've written a
program to test the behavior of how this flag affects signals and had
several reports from people who ran this on various Unix boxes,
confirming that Linux seems to be unique on the way this is handled.
The way NODEFER affects signals on other Unix boxes is as follows:
1) If NODEFER is set, other signals in sa_mask are still blocked.
2) If NODEFER is set and the signal is in sa_mask, then the signal is
still blocked. (Note: this is the behavior of all tested but Linux _and_
NetBSD 2.0 *).
The way NODEFER affects signals on Linux:
1) If NODEFER is set, other signals are _not_ blocked regardless of
sa_mask (Even NetBSD doesn't do this).
2) If NODEFER is set and the signal is in sa_mask, then the signal being
handled is not blocked.
The patch converts signal handling in all current Linux architectures to
the way most Unix boxes work.
Unix boxes that were tested: DU4, AIX 5.2, Irix 6.5, NetBSD 2.0, SFU
3.5 on WinXP, AIX 5.3, Mac OSX, and of course Linux 2.6.13-rcX.
* NetBSD was the only other Unix to behave like Linux on point #2. The
main concern was brought up by point #1 which even NetBSD isn't like
Linux. So with this patch, we leave NetBSD as the lonely one that
behaves differently here with #2.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The acpi-cpufreq driver does a P-state get after a P-state set
to verify whether set went through successfully. This test
is kind of redundant as set goes throught most of the times,
and the test is also expensive as a get of P-states can
take a lot of time (same as a set operation) as it goes
through SMM mode. Effectively, we are doubling the P-state
latency due to this get opertion.
momdule parameter "acpi_pstate_strict" restores orginal paranoia.
http://bugzilla.kernel.org/show_bug.cgi?id=5129
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
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>
i386 floating-point exception handling has a bug that can cause error
code 0 to be sent instead of the proper code during signal delivery.
This is caused by unconditionally checking the IS and c1 bits from the
FPU status word when they are not always relevant. The IS bit tells
whether an exception is a stack fault and is only relevant when the
exception is IE (invalid operation.) The C1 bit determines whether a
stack fault is overflow or underflow and is only relevant when IS and IE
are set.
Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I'm trying to get the nmi working with my laptop (IBM ThinkPad G41) and after
debugging it a while, I found that the nmi code doesn't want to set it up for
this particular CPU.
Here I have:
$ cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 15
model : 4
model name : Mobile Intel(R) Pentium(R) 4 CPU 3.33GHz
stepping : 1
cpu MHz : 3320.084
cache size : 1024 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 1
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 3
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe pni
monitor ds_cpl est tm2 cid xtpr
bogomips : 6642.39
processor : 1
vendor_id : GenuineIntel
cpu family : 15
model : 4
model name : Mobile Intel(R) Pentium(R) 4 CPU 3.33GHz
stepping : 1
cpu MHz : 3320.084
cache size : 1024 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 1
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 3
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe pni
monitor ds_cpl est tm2 cid xtpr
bogomips : 6637.46
And the following code shows:
$ cat linux-2.6.13-rc6/arch/i386/kernel/nmi.c
[...]
void setup_apic_nmi_watchdog (void)
{
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_AMD:
if (boot_cpu_data.x86 != 6 && boot_cpu_data.x86 != 15)
return;
setup_k7_watchdog();
break;
case X86_VENDOR_INTEL:
switch (boot_cpu_data.x86) {
case 6:
if (boot_cpu_data.x86_model > 0xd)
return;
setup_p6_watchdog();
break;
case 15:
if (boot_cpu_data.x86_model > 0x3)
return;
Here I get boot_cpu_data.x86_model == 0x4. So I decided to change it and
reboot. I now seem to have a working NMI. So, unless there's something know
to be bad about this processor and the NMI. I'm submitting the following
patch.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Zwane Mwaikambo <zwane@arm.linux.org.uk>
Acked-by: Mikael Pettersson <mikpe@csd.uu.se>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Since early CPU identify is in this information is already available
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Move the fix to align node_end_pfns to a proper location. The earlier fix
made the node_remap_start_vaddr to get misaligned causing remap_numa_kva to
barf again :-/
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>
This patch add stubs to allow the visws subarch to link again.
Signed-off-by: Tom Duffy <thomas.duffy.99@alumni.brown.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Another x86 subarchitecture bit I missed. This adds both
machine_emergency_restart missed in my reboot fixes and
machine_shutdown needed for kexec support.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Here is one more bit of breakage my x86 sub-architecture
confusion caused.
Add machine_shutdown to voyager so it will compile with CONFIG_KEXEC.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] i386: Implement machine_emergency_reboot
introduced this new function into arch/i386/reboot.c. However,
subarchitectures are entitled to implement their own copies of reboot.c
from which this new function is now missing.
It looks like visws will also need a similar fixup
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Current acpi_register_gsi() function has no way to indicate errors to its
callers even though acpi_register_gsi() can fail to register gsi because of
some reasons (out of memory, lack of interrupt vectors, incorrect BIOS, and so
on). As a result, caller of acpi_register_gsi() cannot handle the case that
acpi_register_gsi() fails. I think failure of acpi_register_gsi() should be
handled properly.
This series of patches changes acpi_register_gsi() to return negative value on
error, and also changes callers of acpi_register_gsi() to handle failure of
acpi_register_gsi().
This patch changes the type of return value of acpi_register_gsi() from
"unsigned int" to "int" to indicate an error. If acpi_register_gsi() fails to
register gsi, it returns negative value.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
We had a user whose apps weren't working correctly because his "rtc" wasn't
working fully.
For the sake of simplicity, it seems sensible to always enable HPET RTC
emulation.
Remove a special config option for HPET_EMULATE_RTC and make it directly
depend on HPET_TIMER and RTC. This will avoid the hangs when EMULATE_RTC
is not configured and when some userlevel script depends on RTC interrupt,
as in:
http://bugzilla.kernel.org/show_bug.cgi?id=4904
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>
Fix bug found by Grant Coady <lkml@dodo.com.au>'s autobuild setup.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We know that the randomisation slows down some workloads on Transmeta CPUs
by quite large amounts. We think it's because the CPU needs to recode the
same x86 instructions when they pop up at a different virtual address after
a fork+exec.
So disable randomization by default on those CPUs.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This removes sys_set_zone_reclaim() for now. While i'm sure Martin is
trying to solve a real problem, we must not hard-code an incomplete and
insufficient approach into a syscall, because syscalls are pretty much
for eternity. I am quite strongly convinced that this syscall must not
hit v2.6.13 in its current form.
Firstly, the syscall lacks basic syscall design: e.g. it allows the
global setting of VM policy for unprivileged users. (!) [ Imagine an
Oracle installation and a SAP installation on the same NUMA box fighting
over the 'optimal' setting for this flag. What will they do? Will they
try to set the flag to their own preferred value every second or so? ]
Secondly, it was added based on a single datapoint from Martin:
http://marc.theaimsgroup.com/?l=linux-mm&m=111763597218177&w=2
where Martin characterizes the numbers the following way:
' Run-to-run variability for "make -j" is huge, so these numbers aren't
terribly useful except to see that with reclaim the benchmark still
finishes in a reasonable amount of time. '
in other words: the fundamental problem has likely not been solved, only
a tendential move into the right direction has been observed, and a
handful of numbers were picked out of a set of hugely variable results,
without showing the variability data. How much variance is there
run-to-run?
I'd really suggest to first walk the walk and see what's needed to get
stable & predictable kernel compilation numbers on that NUMA box, before
adding random syscalls to tune a particular aspect of the VM ... which
approach might not even matter once the whole picture has been analyzed
and understood!
The third, most important point is that the syscall exposes VM tuning
internals in a completely unstructured way. What sense does it make to
have a _GLOBAL_ per-node setting for 'should we go to another node for
reclaim'? If then it might make sense to do this per-app, via numalib or
so.
The change is minimalistic in that it doesnt remove the syscall and the
underlying infrastructure changes, only the user-visible changes. We
could perhaps add a CAP_SYS_ADMIN-only sysctl for this hack, a'ka
/proc/sys/vm/swappiness, but even that looks quite counterproductive
when the generic approach is that we are trying to reduce the number of
external factors in the VM balance picture.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add reference count and disable ACPI PCI Interrupt Link
when no device still uses it.
Warn when drivers have not released Link at suspend time.
http://bugzilla.kernel.org/show_bug.cgi?id=3469
Signed-off-by: David Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Otherwise a platform that supports ACPI based cpufreq
and boots up at lowest possible speed could stay there
forever. This because the governor may request max speed,
but the code doesn't update if there is no change in
speed, and it assumed the initial state of max speed.
http://bugzilla.kernel.org/show_bug.cgi?id=4634
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
The patch addresses a problem with ACPI SCI interrupt entry, which gets
re-used, and the IRQ is assigned to another unrelated device. The patch
corrects the code such that SCI IRQ is skipped and duplicate entry is
avoided. Second issue came up with VIA chipset, the problem was caused by
original patch assigning IRQs starting 16 and up. The VIA chipset uses
4-bit IRQ register for internal interrupt routing, and therefore cannot
handle IRQ numbers assigned to its devices. The patch corrects this
problem by allowing PCI IRQs below 16.
Signed-off by: Natalie Protasevich <Natalie.Protasevich@unisys.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
While reserving KVA for lmem_maps of node, we have to make sure that
node_remap_start_pfn[] is aligned to a proper pmd boundary.
(node_remap_start_pfn[] gets its value from node_end_pfn[])
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>
arch/i386/kernel/cpu/cpufreq/powernow-k8.c:740: warning: unused variable `vid'
arch/i386/kernel/cpu/cpufreq/powernow-k8.c:739: warning: unused variable `fid'
arch/i386/kernel/cpu/cpufreq/powernow-k8.c:743: warning: unused variable `vid'
arch/i386/kernel/cpu/cpufreq/powernow-k8.c:742: warning: unused variable `fid'
arch/i386/kernel/cpu/cpufreq/powernow-k8.c:746: `fid' undeclared (first use in this function)
arch/i386/kernel/cpu/cpufreq/powernow-k8.c:746: `vid' undeclared (first use in this function)
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dave Jones <davej@redhat.com>
For some reason I was telling my inline assembly that the
input argument was an output argument.
Playing in the trampoline code I have seen a couple of
instances where lgdt get the wrong size (because the
trampolines run in 16bit mode) so use lgdtl and lidtl to
be explicit.
Additionally gcc-3.3 and gcc-3.4 want's an lvalue for a
memory argument and it doesn't think an array of characters
is an lvalue so use a packed structure instead.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Somewhere recently, the TSC got re-enabled for timekeeping on NUMAQ
machines. However, the hardware makes these get unsynchronized quite
badly. So badly, in fact, that the code to fix up the skew can just hang
on boot.
This patch re-disables them. It's nicely confined to the numaq.c file. It
would be great if this could make it into 2.6.13, I think it counts as a
bugfix.
Tested on a 16-proc 4-node NUMAQ.
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
powernow-k8.c:110: warning: `hi' may be used uninitialized in this function
Signed-off-by: Brian Gerst <bgerst@didntduck.org>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
can be encoded in the current driver's 4 bit frequency
field. This patch updates the driver to support Rev F
including 6 bit FIDs and processor ID updates.
This should apply cleanly whether or not the dual-core
bugfix I sent out last week is applied. I'd prefer
that both get applied, of course.
Signed-off-by: David Keck <david.keck@amd.com>
Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>
Signed-off-by: Dave Jones <davej@redhat.com>
each core be created in the _cpu_init function
call. The cpufreq infrastructure doesn't call
_cpu_init for the second core in each processor.
Some systems crashed when _get was called with
an odd-numbered core because it tried to
dereference a NULL pointer since the data
structure had not been created.
The attached patch solves the problem by
initializing data structures for all shared
cores in the _cpu_init function. It should
apply to 2.6.12-rc6 and has been tested by
AMD and Sun.
Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>
Signed-off-by: Dave Jones <davej@redhat.com>
This patch:
http://marc.theaimsgroup.com/?l=bk-commits-head&m=111955644929114&w=2
uncovered a k7m bios bug, where the VT82C686A router is reported as
being "586-compatible". The two chips have different pirq mapping, so
this leads to "irq routing conflict" on many pci devices.
The suggested fix was discussed with Aleksey Gorelov, who helped me
to identify the problem as a probable bios bug.
Signed-off-by: Giancarlo Formicuccia <giancarlo.formicuccia@gmail.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
sys_get_thread_area does not memset to 0 its struct user_desc info before
copying it to user space... since sizeof(struct user_desc) is 16 while the
actual datas which are filled are only 12 bytes + 9 bits (across the
bitfields), there is a (small) information leak.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There's no help text for CONFIG_DEBUG_STACKOVERFLOW - add one.
Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
powernow-k8.c: In function `query_current_values_with_pending_wait':
powernow-k8.c:110: warning: `hi' may be used uninitialized in this function
Signed-off-by: Brian Gerst <bgerst@didntduck.org>
Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
machine_power_off now always switches to the boot cpu so there
is no reason for APM to also do that.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Call machine_shutdown() to move to the boot cpu
and disable apics. Both acpi_power_off and
apm_power_off want to move to the boot cpu.
and we are already disabling the local apics
so calling machine_shutdown simply reuses
code.
ia64 doesn't have a special path in power_off
for efi so there is no reason i386 should. If
we really need to call the efi power off path
the efi driver can set pm_power_off like everyone
else.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This appears to be a typo I introduced when cleaning
this code up earlier. Ooops.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
set_cpus_allowed is not safe in interrupt context
and disabling apics is complicated code so don't
call machine_shutdown on i386 from emergency_restart().
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
machine_restart, machine_halt and machine_power_off are machine
specific hooks deep into the reboot logic, that modules
have no business messing with. Usually code should be calling
kernel_restart, kernel_halt, kernel_power_off, or
emergency_restart. So don't export machine_restart,
machine_halt, and machine_power_off so we can catch buggy users.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It is no longer valid to not replace instructions, since we depend on
different behaviour depending on CPU capabilities.
If you need to limit the capabilities of the replacements (because the
boot CPU has features that non-boot CPU's do not have, for example), you
need to explicitly disable those capabilities that are not shared across
all CPU's.
For example, if your boot CPU has FXSR, but other CPU's in your system
do not, you need to use the "nofxsr" kernel command line, not disable
instruction replacement per se.
It's really just a single instruction, conditional on whether the CPU
supports FXSR or not, so implement it as such instead of making it a
function that queries FXSR dynamically.
This means that the instruction just gets automatically rewritten to the
correct one at boot-time.
These days %gs is normally the TLS segment, so it's no longer zero. As
a result, we shouldn't just assume that %fs/%gs tend to be zero
together, but test them independently instead.
Also, fix setting of debug registers to use the "next" pointer instead
of "current". It so happens that the scheduler will have set the new
current pointer before calling __switch_to(), but that's just an
implementation detail.
More fallout from the i386_ksyms.c cleanups.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch:
[PATCH] Remove i386_ksyms.c, almost
made files like smp.c do their own EXPORT_SYMBOLS. This means that all
subarchitectures that override these symbols now have to do the exports
themselves. This patch adds the exports for voyager (which is the most
affected since it has a separate smp harness). However, someone should
audit all the other subarchitectures to see if any others got broken.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
inotify is intended to correct the deficiencies of dnotify, particularly
its inability to scale and its terrible user interface:
* dnotify requires the opening of one fd per each directory
that you intend to watch. This quickly results in too many
open files and pins removable media, preventing unmount.
* dnotify is directory-based. You only learn about changes to
directories. Sure, a change to a file in a directory affects
the directory, but you are then forced to keep a cache of
stat structures.
* dnotify's interface to user-space is awful. Signals?
inotify provides a more usable, simple, powerful solution to file change
notification:
* inotify's interface is a system call that returns a fd, not SIGIO.
You get a single fd, which is select()-able.
* inotify has an event that says "the filesystem that the item
you were watching is on was unmounted."
* inotify can watch directories or files.
Inotify is currently used by Beagle (a desktop search infrastructure),
Gamin (a FAM replacement), and other projects.
See Documentation/filesystems/inotify.txt.
Signed-off-by: Robert Love <rml@novell.com>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Create a new top-level menu named "Networking" thus moving
net related options and protocol selection way from the drivers
menu and up on the top-level where they belong.
To implement this all architectures has to source "net/Kconfig" before
drivers/*/Kconfig in their Kconfig file. This change has been
implemented for all architectures.
Device drivers for ordinary NIC's are still to be found
in the Device Drivers section, but Bluetooth, IrDA and ax25
are located with their corresponding menu entries under the new
networking menu item.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
http://bugme.osdl.org/show_bug.cgi?id=4016
Written-by: David Shaohua Li <shaohua.li@intel.com>
Acked-by: Adam Belay <abelay@novell.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Add a new section called ".data.read_mostly" for data items that are read
frequently and rarely written to like cpumaps etc.
If these maps are placed in the .data section then these frequenly read
items may end up in cachelines with data is is frequently updated. In that
case all processors in an SMP system must needlessly reload the cachelines
again and again containing elements of those frequently used variables.
The ability to share these cachelines will allow each cpu in an SMP system
to keep local copies of those shared cachelines thereby optimizing
performance.
Signed-off-by: Alok N Kataria <alokk@calsoftinc.com>
Signed-off-by: Shobhit Dayal <shobhit@calsoftinc.com>
Signed-off-by: Christoph Lameter <christoph@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>
There has been some discuss about solving the SMP MTRR suspend/resume
breakage, but I didn't find a patch for it. This is an intent for it. The
basic idea is moving mtrr initializing into cpu_identify for all APs (so it
works for cpu hotplug). For BP, restore_processor_state is responsible for
restoring MTRR.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We get sporadic reports of `__iounmap: bad address' coming out. Add a
dump_stack() to find the culprit.
Try to identify which subsystem is having iounmap() problems.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following renames arch_init, a kprobes function for performing any
architecture specific initialization, to arch_init_kprobes in order to
cleanup the namespace.
Also, this patch adds arch_init_kprobes to sparc64 to fix the sparc64 kprobes
build from the last return probe patch.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The dynamic pci id logic has been bothering me for a while, and now that
I started to look into how to move some of this to the driver core, I
thought it was time to clean it all up.
It ends up making the code smaller, and easier to follow, and fixes a
few bugs at the same time (dynamic ids were not being matched
everywhere, and so could be missed on some call paths for new devices,
semaphore not needed to be grabbed when adding a new id and calling the
driver core, etc.)
I also renamed the function pci_match_device() to pci_match_id() as
that's what it really does.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
- Add sanity check for io[port,mem]_resource in setup-bus.c. These
resources look like "free" as they have no parents, but obviously
we must not touch them.
- In i386.c:pci_allocate_bus_resources(), if a bridge resource cannot be
allocated for some reason, then clear its flags. This prevents any child
allocations in this range, so the setup-bus code will work with a clean
resource sub-tree.
- i386.c:pcibios_enable_resources() doesn't enable bridges, as it checks
only resources 0-5, which looks like a clear bug to me. I suspect it
might break hotplug as well in some cases.
From: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Variable "c" was declared as an unsigned int, but used in:
125 for (i=0 ; (c=read(fd, buf, sizeof(buf)))>0 ; i+=c )
126 if (write(1, buf, c) != c)
127 die("Write call failed");
(akpm: read() can return -1. If it does, we fill the disk up with garbage).
Signed-off-by: Zaur Kambarov <zkambarov@coverity.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Zachary Amsden