Since LRW & XTS are selected by serpent-sse2, we don't need these #ifdefs
anymore.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since LRW & XTS are selected by twofish-x86_64-3way, we don't need these
#ifdefs anymore.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When printing the code bytes in show_registers(), the markers around the
byte at the fault address could make the printk() format string look
like a valid log level and facility code. This would prevent this byte
from being printed and result in a spurious newline:
[ 7555.765589] Code: 8b 32 e9 94 00 00 00 81 7d 00 ff 00 00 00 0f 87 96 00 00 00 48 8b 83 c0 00 00 00 44 89 e2 44 89 e6 48 89 df 48 8b 80 d8 02 00 00
[ 7555.765683] 8b 48 28 48 89 d0 81 e2 ff 0f 00 00 48 c1 e8 0c 48 c1 e0 04
Add KERN_CONT where needed, and elsewhere in show_registers() for
consistency.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Link: http://lkml.kernel.org/r/4EEFA7AE.9020407@ladisch.de
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
x86 jump instruction size is 2 or 5 bytes (near/long jump), not 2 or 6
bytes.
In case a conditional jump is followed by a long jump, conditional jump
target is one byte past the start of target instruction.
Signed-off-by: Markus Kötter <nepenthesdev@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
LAPIC related statistics are grouped inside the per-cpu
structure irq_stat, so there is no need for icr_read_retry_count
to be a standalone per-cpu variable.
This patch moves icr_read_retry_count to where it belongs.
Suggested-y: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Cc: Jörn Engel <joern@logfs.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Added additional debug output that we always seem to add
during power ons to validate firmware operation.
Signed-off-by: Michael Demeter <michael.demeter@intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Link: http://lkml.kernel.org/r/20111215223116.10166.50803.stgit@bob.linux.org.uk
[ fixed line breaks, formatting and commit title. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
gcc noticed (when using -Wempty-body) that our use of
lock_cmos() and unlock_cmos() in
arch/x86/include/asm/mach_traps.h is potentially problematic :
arch/x86/include/asm/mach_traps.h:32:15: warning: suggest braces around empty body in an ¡else¢ statement [-Wempty-body]
arch/x86/include/asm/mach_traps.h:40:16: warning: suggest braces around empty body in an ¡else¢ statement [-Wempty-body]
Let's just use the standard 'do {} while (0)' solution. That
shuts up gcc and also prevents future problems if the macros
should end up being used in a similar situation elsewhere.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1112180103130.21784@swampdragon.chaosbits.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If one builds the kernel with -Wempty-body one gets this
warning:
mm/memory.c:3432:46: warning: suggest braces around empty body in an ¡if¢ statement [-Wempty-body]
due to the fact that 'flush_tlb_fix_spurious_fault' is a macro
that can sometimes be defined to nothing.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: linux-mm@kvack.org
Cc: Michel Lespinasse <walken@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1112180128070.21784@swampdragon.chaosbits.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>
mce-inject provides a mechanism to simulate errors so that test
scripts can check for correct operation of the kernel without
requiring any specialized hardware to create rare events.
The existing code can simulate events in normal process context
and also in NMI context - but not in IRQ context. This patch
fills that gap.
Link: https://lkml.org/lkml/2011/12/7/537
Signed-off-by: Chen Gong <gong.chen@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
The efi boot stub tries to read the entire initrd in 1 go, however
some efi implementations hang if too much if asked to read too much
data at the same time. After some experimentation I found out that my
asrock p67 board will hang if asked to read chunks of 4MiB, so use a
safe value.
elilo reads in chunks of 16KiB, but since that requires many read
calls I use a value of 1 MiB. hpa suggested adding individual
blacklists for when systems are found where this value causes a crash.
Signed-off-by: Maarten Lankhorst <m.b.lankhorst@gmail.com>
Link: http://lkml.kernel.org/r/4EEB3A02.3090201@gmail.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Doh.. pass the brown paper bags - preferably filled with mince
pies..
This fixes occasional build failures.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-r0oc1knlvzuqr69artaeq8s8@git.kernel.org
[ extended the changelog a bit ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
fls(N), ffs(N) and fls64(N) can be optimised on x86_64. Currently they use a
CMOV instruction after the BSR/BSF to set the destination register to -1 if the
value to be scanned was 0 (in which case BSR/BSF set the Z flag).
Instead, according to the AMD64 specification, we can make use of the fact that
BSR/BSF doesn't modify its output register if its input is 0. By preloading
the output with -1 and incrementing the result, we achieve the desired result
without the need for a conditional check.
The Intel x86_64 specification, however, says that the result of BSR/BSF in
such a case is undefined. That said, when queried, one of the Intel CPU
architects said that the behaviour on all Intel CPUs is that:
(1) with BSRQ/BSFQ, the 64-bit destination register is written with its
original value if the source is 0, thus, in essence, giving the effect we
want. And,
(2) with BSRL/BSFL, the lower half of the 64-bit destination register is
written with its original value if the source is 0, and the upper half is
cleared, thus giving us the effect we want (we return a 4-byte int).
Further, it was indicated that they (Intel) are unlikely to get away with
changing the behaviour.
It might be possible to optimise the 32-bit versions of these functions, but
there's a lot more variation, and so the effective non-destructive property of
BSRL/BSRF cannot be relied on.
[ hpa: specifically, some 486 chips are known to NOT have this property. ]
I have benchmarked these functions on my Core2 Duo test machine using the
following program:
#include <stdlib.h>
#include <stdio.h>
#ifndef __x86_64__
#error
#endif
#define PAGE_SHIFT 12
typedef unsigned long long __u64, u64;
typedef unsigned int __u32, u32;
#define noinline __attribute__((noinline))
static __always_inline int fls64(__u64 x)
{
long bitpos = -1;
asm("bsrq %1,%0"
: "+r" (bitpos)
: "rm" (x));
return bitpos + 1;
}
static inline unsigned long __fls(unsigned long word)
{
asm("bsr %1,%0"
: "=r" (word)
: "rm" (word));
return word;
}
static __always_inline int old_fls64(__u64 x)
{
if (x == 0)
return 0;
return __fls(x) + 1;
}
static noinline // __attribute__((const))
int old_get_order(unsigned long size)
{
int order;
size = (size - 1) >> (PAGE_SHIFT - 1);
order = -1;
do {
size >>= 1;
order++;
} while (size);
return order;
}
static inline __attribute__((const))
int get_order_old_fls64(unsigned long size)
{
int order;
size--;
size >>= PAGE_SHIFT;
order = old_fls64(size);
return order;
}
static inline __attribute__((const))
int get_order(unsigned long size)
{
int order;
size--;
size >>= PAGE_SHIFT;
order = fls64(size);
return order;
}
unsigned long prevent_optimise_out;
static noinline unsigned long test_old_get_order(void)
{
unsigned long n, total = 0;
long rep, loop;
for (rep = 1000000; rep > 0; rep--) {
for (loop = 0; loop <= 16384; loop += 4) {
n = 1UL << loop;
total += old_get_order(n);
}
}
return total;
}
static noinline unsigned long test_get_order_old_fls64(void)
{
unsigned long n, total = 0;
long rep, loop;
for (rep = 1000000; rep > 0; rep--) {
for (loop = 0; loop <= 16384; loop += 4) {
n = 1UL << loop;
total += get_order_old_fls64(n);
}
}
return total;
}
static noinline unsigned long test_get_order(void)
{
unsigned long n, total = 0;
long rep, loop;
for (rep = 1000000; rep > 0; rep--) {
for (loop = 0; loop <= 16384; loop += 4) {
n = 1UL << loop;
total += get_order(n);
}
}
return total;
}
int main(int argc, char **argv)
{
unsigned long total;
switch (argc) {
case 1: total = test_old_get_order(); break;
case 2: total = test_get_order_old_fls64(); break;
default: total = test_get_order(); break;
}
prevent_optimise_out = total;
return 0;
}
This allows me to test the use of the old fls64() implementation and the new
fls64() implementation and also to contrast these to the out-of-line loop-based
implementation of get_order(). The results were:
warthog>time ./get_order
real 1m37.191s
user 1m36.313s
sys 0m0.861s
warthog>time ./get_order x
real 0m16.892s
user 0m16.586s
sys 0m0.287s
warthog>time ./get_order x x
real 0m7.731s
user 0m7.727s
sys 0m0.002s
Using the current upstream fls64() as a basis for an inlined get_order() [the
second result above] is much faster than using the current out-of-line
loop-based get_order() [the first result above].
Using my optimised inline fls64()-based get_order() [the third result above]
is even faster still.
[ hpa: changed the selection of 32 vs 64 bits to use CONFIG_X86_64
instead of comparing BITS_PER_LONG, updated comments, rebased manually
on top of 83d99df7c4 x86, bitops: Move fls64.h inside __KERNEL__ ]
Signed-off-by: David Howells <dhowells@redhat.com>
Link: http://lkml.kernel.org/r/20111213145654.14362.39868.stgit@warthog.procyon.org.uk
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
We would include <asm-generic/bitops/fls64.h> even without __KERNEL__,
but that doesn't make sense, as:
1. That file provides fls64(), but the corresponding function fls() is
not exported to user space.
2. The implementation of fls64.h uses kernel-only symbols.
3. fls64.h is not exported to user space.
This appears to have been a bug introduced in checkin:
d57594c203 bitops: use __fls for fls64 on 64-bit archs
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Alexander van Heukelum <heukelum@mailshack.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/4EEA77E1.6050009@zytor.com
* 'stable/for-linus-fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/swiotlb: Use page alignment for early buffer allocation.
xen: only limit memory map to maximum reservation for domain 0.
d312ae878b "xen: use maximum reservation to limit amount of usable RAM"
clamped the total amount of RAM to the current maximum reservation. This is
correct for dom0 but is not correct for guest domains. In order to boot a guest
"pre-ballooned" (e.g. with memory=1G but maxmem=2G) in order to allow for
future memory expansion the guest must derive max_pfn from the e820 provided by
the toolstack and not the current maximum reservation (which can reflect only
the current maximum, not the guest lifetime max). The existing algorithm
already behaves this correctly if we do not artificially limit the maximum
number of pages for the guest case.
For a guest booted with maxmem=512, memory=128 this results in:
[ 0.000000] BIOS-provided physical RAM map:
[ 0.000000] Xen: 0000000000000000 - 00000000000a0000 (usable)
[ 0.000000] Xen: 00000000000a0000 - 0000000000100000 (reserved)
-[ 0.000000] Xen: 0000000000100000 - 0000000008100000 (usable)
-[ 0.000000] Xen: 0000000008100000 - 0000000020800000 (unusable)
+[ 0.000000] Xen: 0000000000100000 - 0000000020800000 (usable)
...
[ 0.000000] NX (Execute Disable) protection: active
[ 0.000000] DMI not present or invalid.
[ 0.000000] e820 update range: 0000000000000000 - 0000000000010000 (usable) ==> (reserved)
[ 0.000000] e820 remove range: 00000000000a0000 - 0000000000100000 (usable)
-[ 0.000000] last_pfn = 0x8100 max_arch_pfn = 0x1000000
+[ 0.000000] last_pfn = 0x20800 max_arch_pfn = 0x1000000
[ 0.000000] initial memory mapped : 0 - 027ff000
[ 0.000000] Base memory trampoline at [c009f000] 9f000 size 4096
-[ 0.000000] init_memory_mapping: 0000000000000000-0000000008100000
-[ 0.000000] 0000000000 - 0008100000 page 4k
-[ 0.000000] kernel direct mapping tables up to 8100000 @ 27bb000-27ff000
+[ 0.000000] init_memory_mapping: 0000000000000000-0000000020800000
+[ 0.000000] 0000000000 - 0020800000 page 4k
+[ 0.000000] kernel direct mapping tables up to 20800000 @ 26f8000-27ff000
[ 0.000000] xen: setting RW the range 27e8000 - 27ff000
[ 0.000000] 0MB HIGHMEM available.
-[ 0.000000] 129MB LOWMEM available.
-[ 0.000000] mapped low ram: 0 - 08100000
-[ 0.000000] low ram: 0 - 08100000
+[ 0.000000] 520MB LOWMEM available.
+[ 0.000000] mapped low ram: 0 - 20800000
+[ 0.000000] low ram: 0 - 20800000
With this change "xl mem-set <domain> 512M" will successfully increase the
guest RAM (by reducing the balloon).
There is no change for dom0.
Reported-and-Tested-by: George Shuklin <george.shuklin@gmail.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: stable@kernel.org
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
My box with following cpuinfo needs the cx8 enabling still:
vendor_id : CentaurHauls
cpu family : 6
model : 13
model name : VIA Eden Processor 1200MHz
stepping : 0
cpu MHz : 1199.940
cache size : 128 KB
This fixes valgrind to work on my box (it requires and checks
cx8 from cpuinfo).
Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Link: http://lkml.kernel.org/r/1323961888-10223-1-git-send-email-timo.teras@iki.fi
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
They had several problems/shortcomings:
Only the first memory operand was mentioned in the 2x32bit asm()
operands, and 2x64-bit version had a memory clobber. The first
allowed the compiler to not recognize the need to re-load the
data in case it had it cached in some register, and the second
was overly destructive.
The memory operand in the 2x32-bit asm() was declared to only be
an output.
The types of the local copies of the old and new values were
incorrect (as in other per-CPU ops, the types of the per-CPU
variables accessed should be used here, to make sure the
respective types are compatible).
The __dummy variable was pointless (and needlessly initialized
in the 2x32-bit case), given that local copies of the inputs
already exist.
The 2x64-bit variant forced the address of the first object into
%rsi, even though this is needed only for the call to the
emulation function. The real cmpxchg16b can operate on an
memory.
At once also change the return value type to what it really is -
'bool'.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4EE86D6502000078000679FE@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add the flags to get rid of the [9] and [10] feature names
in cpuinfo's 'power management' fields and replace them with
meaningful names.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Link: http://lkml.kernel.org/r/1323875574-17881-1-git-send-email-joerg.roedel@amd.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Thermal throttle and power limit events are not defined as MCE errors in x86
architecture and should not generate MCE errors in mcelog.
Current kernel generates fake software defined MCE errors for these events.
This may confuse users because they may think the machine has real MCE errors
while actually only thermal throttle or power limit events happen.
To make it worse, buggy firmware on some platforms may falsely generate
the events. Therefore, kernel reports MCE errors which users think as real
hardware errors. Although the firmware bugs should be fixed, on the other hand,
kernel should not report MCE errors either.
So mcelog is not a good mechanism to report these events. To report the events, we count them in respective counters (core_power_limit_count,
package_power_limit_count, core_throttle_count, and package_throttle_count) in
/sys/devices/system/cpu/cpu#/thermal_throttle/. Users can check the counters
for each event on each CPU. Please note that all CPU's on one package report
duplicate counters. It's user application's responsibity to retrieve a package
level counter for one package.
This patch doesn't report package level power limit, core level power limit, and
package level thermal throttle events in mcelog. When the events happen, only
report them in respective counters in sysfs.
Since core level thermal throttle has been legacy code in kernel for a while and
users accepted it as MCE error in mcelog, core level thermal throttle is still
reported in mcelog. In the mean time, the event is counted in a counter in sysfs
as well.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Borislav Petkov <bp@amd64.org>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20111215001945.GA21009@linux-os.sc.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Add a function which drains whatever MCEs were logged in already during
boot and before the decoder chains were registered.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
No functionality change, this is done so that in a follow-on patch all
queued-up MCEs can be decoded after registering on the chain.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Once we've found and validated the ucode patch for the current CPU,
there's no need to iterate over the remaining patches in the binary
image. Exit then and save us a bunch of cycles.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Basically, what we did until now is take out a chunk of the firmware
image, vmalloc space for it and inspect it before application. And
repeat.
This patch changes all that so that we look at each ucode patch from
the firmware image, check it for sanity and copy it to local buffer for
application only once and if it passes all checks. Thus, vmalloc-ing for
each piece is gone, we can do proper size checking only of the patch
which is destined for the CPU of the current machine instead of each
single patch, which is clearly wrong.
Oh yeah, simplify and cleanup the code while at it, along with adding
comments as to what actually happens.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Add a simple 4K page which gets allocated on driver init and freed on
driver exit instead of vmalloc'ing small buffers for each ucode patch.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
In the IPI delivery slow path (NMI delivery) we retry the ICR
read to check for delivery completion a limited number of times.
[ The reason for the limited retries is that some of the places
where it is used (cpu boot, kdump, etc) IPI delivery might not
succeed (due to a firmware bug or system crash, for example)
and in such a case it is better to give up and resume
execution of other code. ]
This patch adds a new entry to /proc/interrupts, RTR, which
tells user space the number of times we retried the ICR read in
the IPI delivery slow path.
This should give some insight into how well the APIC
message delivery hardware is working - if the counts are way
too large then we are hitting a (very-) slow path way too
often.
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Cc: Jörn Engel <joern@logfs.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/n/tip-vzsp20lo2xdzh5f70g0eis2s@git.kernel.org
[ extended the changelog ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
There is currently a large divide between kernel development and the
development of EFI boot loaders. The idea behind this patch is to give
the kernel developers full control over the EFI boot process. As
H. Peter Anvin put it,
"The 'kernel carries its own stub' approach been very successful in
dealing with BIOS, and would make a lot of sense to me for EFI as
well."
This patch introduces an EFI boot stub that allows an x86 bzImage to
be loaded and executed by EFI firmware. The bzImage appears to the
firmware as an EFI application. Luckily there are enough free bits
within the bzImage header so that it can masquerade as an EFI
application, thereby coercing the EFI firmware into loading it and
jumping to its entry point. The beauty of this masquerading approach
is that both BIOS and EFI boot loaders can still load and run the same
bzImage, thereby allowing a single kernel image to work in any boot
environment.
The EFI boot stub supports multiple initrds, but they must exist on
the same partition as the bzImage. Command-line arguments for the
kernel can be appended after the bzImage name when run from the EFI
shell, e.g.
Shell> bzImage console=ttyS0 root=/dev/sdb initrd=initrd.img
v7:
- Fix checkpatch warnings.
v6:
- Try to allocate initrd memory just below hdr->inird_addr_max.
v5:
- load_options_size is UTF-16, which needs dividing by 2 to convert
to the corresponding ASCII size.
v4:
- Don't read more than image->load_options_size
v3:
- Fix following warnings when compiling CONFIG_EFI_STUB=n
arch/x86/boot/tools/build.c: In function ‘main’:
arch/x86/boot/tools/build.c:138:24: warning: unused variable ‘pe_header’
arch/x86/boot/tools/build.c:138:15: warning: unused variable ‘file_sz’
- As reported by Matthew Garrett, some Apple machines have GOPs that
don't have hardware attached. We need to weed these out by
searching for ones that handle the PCIIO protocol.
- Don't allocate memory if no initrds are on cmdline
- Don't trust image->load_options_size
Maarten Lankhorst noted:
- Don't strip first argument when booted from efibootmgr
- Don't allocate too much memory for cmdline
- Don't update cmdline_size, the kernel considers it read-only
- Don't accept '\n' for initrd names
v2:
- File alignment was too large, was 8192 should be 512. Reported by
Maarten Lankhorst on LKML.
- Added UGA support for graphics
- Use VIDEO_TYPE_EFI instead of hard-coded number.
- Move linelength assignment until after we've assigned depth
- Dynamically fill out AddressOfEntryPoint in tools/build.c
- Don't use magic number for GDT/TSS stuff. Requested by Andi Kleen
- The bzImage may need to be relocated as it may have been loaded at
a high address address by the firmware. This was required to get my
macbook booting because the firmware loaded it at 0x7cxxxxxx, which
triggers this error in decompress_kernel(),
if (heap > ((-__PAGE_OFFSET-(128<<20)-1) & 0x7fffffff))
error("Destination address too large");
Cc: Mike Waychison <mikew@google.com>
Cc: Matthew Garrett <mjg@redhat.com>
Tested-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1321383097.2657.9.camel@mfleming-mobl1.ger.corp.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Current i386 strlen() hardcodes NOT/DEC sequence. DEC is
mentioned to be suboptimal on Core2. So, put only REPNE SCASB
sequence in assembly, compiler can do the rest.
The difference in generated code is like below (MCORE2=y):
<strlen>:
push %edi
mov $0xffffffff,%ecx
mov %eax,%edi
xor %eax,%eax
repnz scas %es:(%edi),%al
not %ecx
- dec %ecx
- mov %ecx,%eax
+ lea -0x1(%ecx),%eax
pop %edi
ret
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jan Beulich <JBeulich@suse.com>
Link: http://lkml.kernel.org/r/20111211181319.GA17097@p183.telecom.by
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This hangs my MacBook Air at boot time; I get no console
messages at all. I reverted this on top of -rc5 and my machine
boots again.
This reverts commit e8c7106280.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Huang Ying <huang.ying.caritas@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1321621751-3650-1-git-send-email-matt@console
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Those two APIs were provided to optimize the calls of
tick_nohz_idle_enter() and rcu_idle_enter() into a single
irq disabled section. This way no interrupt happening in-between would
needlessly process any RCU job.
Now we are talking about an optimization for which benefits
have yet to be measured. Let's start simple and completely decouple
idle rcu and dyntick idle logics to simplify.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The idle notifier, called by enter_idle(), enters into rcu read
side critical section but at that time we already switched into
the RCU-idle window (rcu_idle_enter() has been called). And it's
illegal to use rcu_read_lock() in that state.
This results in rcu reporting its bad mood:
[ 1.275635] WARNING: at include/linux/rcupdate.h:194 __atomic_notifier_call_chain+0xd2/0x110()
[ 1.275635] Hardware name: AMD690VM-FMH
[ 1.275635] Modules linked in:
[ 1.275635] Pid: 0, comm: swapper Not tainted 3.0.0-rc6+ #252
[ 1.275635] Call Trace:
[ 1.275635] [<ffffffff81051c8a>] warn_slowpath_common+0x7a/0xb0
[ 1.275635] [<ffffffff81051cd5>] warn_slowpath_null+0x15/0x20
[ 1.275635] [<ffffffff817d6f22>] __atomic_notifier_call_chain+0xd2/0x110
[ 1.275635] [<ffffffff817d6f71>] atomic_notifier_call_chain+0x11/0x20
[ 1.275635] [<ffffffff810018a0>] enter_idle+0x20/0x30
[ 1.275635] [<ffffffff81001995>] cpu_idle+0xa5/0x110
[ 1.275635] [<ffffffff817a7465>] rest_init+0xe5/0x140
[ 1.275635] [<ffffffff817a73c8>] ? rest_init+0x48/0x140
[ 1.275635] [<ffffffff81cc5ca3>] start_kernel+0x3d1/0x3dc
[ 1.275635] [<ffffffff81cc5321>] x86_64_start_reservations+0x131/0x135
[ 1.275635] [<ffffffff81cc5412>] x86_64_start_kernel+0xed/0xf4
[ 1.275635] ---[ end trace a22d306b065d4a66 ]---
Fix this by entering rcu extended quiescent state later, just before
the CPU goes to sleep.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
It is assumed that rcu won't be used once we switch to tickless
mode and until we restart the tick. However this is not always
true, as in x86-64 where we dereference the idle notifiers after
the tick is stopped.
To prepare for fixing this, add two new APIs:
tick_nohz_idle_enter_norcu() and tick_nohz_idle_exit_norcu().
If no use of RCU is made in the idle loop between
tick_nohz_enter_idle() and tick_nohz_exit_idle() calls, the arch
must instead call the new *_norcu() version such that the arch doesn't
need to call rcu_idle_enter() and rcu_idle_exit().
Otherwise the arch must call tick_nohz_enter_idle() and
tick_nohz_exit_idle() and also call explicitly:
- rcu_idle_enter() after its last use of RCU before the CPU is put
to sleep.
- rcu_idle_exit() before the first use of RCU after the CPU is woken
up.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The tick_nohz_stop_sched_tick() function, which tries to delay
the next timer tick as long as possible, can be called from two
places:
- From the idle loop to start the dytick idle mode
- From interrupt exit if we have interrupted the dyntick
idle mode, so that we reprogram the next tick event in
case the irq changed some internal state that requires this
action.
There are only few minor differences between both that
are handled by that function, driven by the ts->inidle
cpu variable and the inidle parameter. The whole guarantees
that we only update the dyntick mode on irq exit if we actually
interrupted the dyntick idle mode, and that we enter in RCU extended
quiescent state from idle loop entry only.
Split this function into:
- tick_nohz_idle_enter(), which sets ts->inidle to 1, enters
dynticks idle mode unconditionally if it can, and enters into RCU
extended quiescent state.
- tick_nohz_irq_exit() which only updates the dynticks idle mode
when ts->inidle is set (ie: if tick_nohz_idle_enter() has been called).
To maintain symmetry, tick_nohz_restart_sched_tick() has been renamed
into tick_nohz_idle_exit().
This simplifies the code and micro-optimize the irq exit path (no need
for local_irq_save there). This also prepares for the split between
dynticks and rcu extended quiescent state logics. We'll need this split to
further fix illegal uses of RCU in extended quiescent states in the idle
loop.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Introduce a symbol, EFI_LOADER_SIGNATURE instead of using the magic
strings, which also helps to reduce the amount of ifdeffery.
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1318848017-12301-1-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
commit 37ba7ab5e3 ("x86, boot: make kernel_alignment adjustable; new
bzImage fields") introduced some new fields into the bzImage header
but struct setup_header was not updated accordingly. Add the missing
'pref_address' and 'init_size' fields.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1318848017-12301-1-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
efi_call_phys_prelog() sets up a 1:1 mapping of the physical address
range in swapper_pg_dir. Instead of replacing then restoring entries
in swapper_pg_dir we should be using initial_page_table which already
contains the 1:1 mapping.
It's safe to blindly switch back to swapper_pg_dir in the epilog
because the physical EFI routines are only called before
efi_enter_virtual_mode(), e.g. before any user processes have been
forked. Therefore, we don't need to track which pgd was in %cr3 when
we entered the prelog.
The previous code actually contained a bug because it assumed that the
kernel was loaded at a physical address within the first 8MB of ram,
usually at 0x100000. However, this isn't the case with a
CONFIG_RELOCATABLE=y kernel which could have been loaded anywhere in
the physical address space.
Also delete the ancient (and bogus) comments about the page table
being restored after the lock is released. There is no locking.
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Darrent Hart <dvhart@linux.intel.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1323346250.3894.74.camel@mfleming-mobl1.ger.corp.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, efi: Calling __pa() with an ioremap()ed address is invalid
x86, hpet: Immediately disable HPET timer 1 if rtc irq is masked
x86/intel_mid: Kconfig select fix
x86/intel_mid: Fix the Kconfig for MID selection
We override sys_iopl(), not stub_iopl(); the latter is a 64-bitism
that doesn't apply to i386 in the first place.
Reported-by: Richard Weinberger <richard@nod.at>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
With the 3.2-rc kernel, IOMMU 2M pages in KVM works. But when I tried
to use IOMMU 1GB pages in KVM, I encountered an oops and the 1GB page
failed to be used.
The root cause is that 1GB page allocation calls gup_huge_pud() while 2M
page calls gup_huge_pmd. If compound pages are used and the page is a
tail page, gup_huge_pmd() increases _mapcount to record tail page are
mapped while gup_huge_pud does not do that.
So when the mapped page is relesed, it will result in kernel oops
because the page is not marked mapped.
This patch add tail process for compound page in 1GB huge page which
keeps the same process as 2M page.
Reproduce like:
1. Add grub boot option: hugepagesz=1G hugepages=8
2. mount -t hugetlbfs -o pagesize=1G hugetlbfs /dev/hugepages
3. qemu-kvm -m 2048 -hda os-kvm.img -cpu kvm64 -smp 4 -mem-path /dev/hugepages
-net none -device pci-assign,host=07:00.1
kernel BUG at mm/swap.c:114!
invalid opcode: 0000 [#1] SMP
Call Trace:
put_page+0x15/0x37
kvm_release_pfn_clean+0x31/0x36
kvm_iommu_put_pages+0x94/0xb1
kvm_iommu_unmap_memslots+0x80/0xb6
kvm_assign_device+0xba/0x117
kvm_vm_ioctl_assigned_device+0x301/0xa47
kvm_vm_ioctl+0x36c/0x3a2
do_vfs_ioctl+0x49e/0x4e4
sys_ioctl+0x5a/0x7c
system_call_fastpath+0x16/0x1b
RIP put_compound_page+0xd4/0x168
Signed-off-by: Youquan Song <youquan.song@intel.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
