mtr_aps_delayed_init was declared u32 and made global, but it only
ever takes boolean values and is only ever used in
arch/x86/kernel/cpu/mtrr/main.c. Declare it "static bool" and remove
external references.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
SDM Vol 3a section titled "MTRR considerations in MP systems" specifies
the need for synchronizing the logical cpu's while initializing/updating
MTRR.
Currently Linux kernel does the synchronization of all cpu's only when
a single MTRR register is programmed/updated. During an AP online
(during boot/cpu-online/resume) where we initialize all the MTRR/PAT registers,
we don't follow this synchronization algorithm.
This can lead to scenarios where during a dynamic cpu online, that logical cpu
is initializing MTRR/PAT with cache disabled (cr0.cd=1) etc while other logical
HT sibling continue to run (also with cache disabled because of cr0.cd=1
on its sibling).
Starting from Westmere, VMX transitions with cr0.cd=1 don't work properly
(because of some VMX performance optimizations) and the above scenario
(with one logical cpu doing VMX activity and another logical cpu coming online)
can result in system crash.
Fix the MTRR initialization by doing rendezvous of all the cpus. During
boot and resume, we delay the MTRR/PAT init for APs till all the
logical cpu's come online and the rendezvous process at the end of AP's bringup,
will initialize the MTRR/PAT for all AP's.
For dynamic single cpu online, we synchronize all the logical cpus and
do the MTRR/PAT init on the AP that is coming online.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Fix following trivial style problems:
ERROR: trailing whitespace X 25
WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>
WARNING: Use #include <linux/kvm_para.h> instead of <asm/kvm_para.h>
ERROR: do not initialise externals to 0 or NULL X 2
ERROR: "foo * bar" should be "foo *bar" X 5
ERROR: do not use assignment in if condition X 2
WARNING: line over 80 characters X 8
ERROR: return is not a function, parentheses are not required
WARNING: braces {} are not necessary for any arm of this statement
ERROR: space required before the open parenthesis '(' X 2
ERROR: open brace '{' following function declarations go on the next line
ERROR: space required after that ',' (ctx:VxV) X 8
ERROR: space required before the open parenthesis '(' X 3
ERROR: else should follow close brace '}'
WARNING: space prohibited between function name and open parenthesis '('
WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable X 2
Also use pr_debug and pr_warning where possible.
total: 50 errors, 14 warnings
arch/x86/kernel/cpu/mtrr/main.o:
text data bss dec hex filename
3668 116 4156 7940 1f04 main.o.before
3668 116 4156 7940 1f04 main.o.after
md5:
e01af2fd28deef77c8d01e71acfbd365 main.o.before.asm
e01af2fd28deef77c8d01e71acfbd365 main.o.after.asm
Suggested-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20090703164225.GA21447@elte.hu>
Cc: Avi Kivity <avi@redhat.com> # Avi, please have a look at the kvm_para.h bit
[ More cleanups ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use standard msr-index.h's MSR declaration and no need to declare again.
[ Impact: cleanup, no object code change ]
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: don't trim e820 according to wrong mtrr
Ozan reports that his server emits strange warning.
it turns out the BIOS sets the MTRRs incorrectly.
Ignore those strange ranges, and don't trim e820,
just emit one warning about BIOS
Reported-by: Ozan Çağlayan <ozan@pardus.org.tr>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <49BEE1E7.7020706@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
mtrr main.c is too big, seperate mtrr cleanup and mtrr e820 trim
code to another file.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <49B87C7B.80809@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: print more debug info
Keep it consistent with autodetect version.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <49B87C0A.4010105@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
kerneloops.org is reporting a lot of these warnings that come due to
vmware not setting up any MTRRs for emulated CPUs:
| Reported 709 times (14696 total reports)
| BIOS bug (often in VMWare) where the MTRR's are set up incorrectly
| or not at all
|
| This warning was last seen in version 2.6.29-rc2-git1, and first
| seen in 2.6.24.
|
| More info:
| http://www.kerneloops.org/searchweek.php?search=mtrr_trim_uncached_memory
Keep a one-liner KERN_INFO about it - so that we have so notice if empty
MTRRs are caused by native hardware/BIOS weirdness.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
enable_mtrr_cleanup is static, and is never set to anything but 0 or 1.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Ingo said mtrr_cleanup() is big and ugly.
so break it up into more functions and make it more readable.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
For the purpose of MTRR canonicalization, treat WRPROT as UNCACHEABLE.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
The first 1M is don't care when it comes to the variables MTRRs.
Cover it as WB as a heuristic approximation; this is generally what we
want to minimize the number of registers.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Print out the correct type when the Write Protected (WP) type is seen.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Delay exit to make sure we can actually get the optimal result in as
many cases as possible.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
v2: should check with half of range0 size instead of chunk_size
So don't have silly big hole.
in hpa's case we could auto detect instead of adding mtrr_chunk_size in
command line.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
add mtrr_cleanup_debug to print out more info about layout
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
change back chunksize max to 2g
otherwise will get strange layout in 2G ram system like
0 - 4g WB, 2040M - 2048M UC, 2048M - 4G NC
instead of
0 - 2g WB, 2040M - 2048M UC
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
fix this warning reported by Andrew Morton:
> arch/x86/kernel/cpu/mtrr/main.c: In function 'mtrr_bp_init':
> arch/x86/kernel/cpu/mtrr/main.c:1170: warning: 'extra_remove_base' may be used uninitialized in this function
the warning is bogus but the logic that prevents uninitialized use
is a bit convoluted so simplify it all.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use WARN() instead of a printk+WARN_ON() pair; this way the message
becomes part of the warning section for better reporting/collection.
This also allowed the folding of some if()'s into the WARN()
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: akpm@linux-foundation.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
rename update_memory_range to e820_update_range
rename add_memory_region to e820_add_region
to make it more clear that they are about e820 map operations.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
It's never used and the comments refer to nonatomic and retry
interchangably. So get rid of it.
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
disable the noisy print out.
also use the one the less spare mtrr reg.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Loop through mtrr chunk_size and gran_size from 1M to 2G to find out
the optimal value so user does not need to add mtrr_chunk_size and
mtrr_gran_size to the kernel command line.
If optimal value is not found, print out all list to help select less
optimal value.
Add mtrr_spare_reg_nr= so user could set 2 instead of 1, if the card
need more entries.
v2: find the one with more spare entries
v3: fix hole_basek offset
v4: tight the compare between range and range_new
loop stop with 4g
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Gabriel C <nix.or.die@googlemail.com>
Cc: Mika Fischer <mika.fischer@zoopnet.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
v9: address format change requests by Ingo
more case handling in range_to_var_with_hole
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
v2: process hole then end_pfn
fix update_memory_range with whole cover comparing
Signed-off-by: Yinghai Lu <yinghai.lu@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
converting MTRR layout from continous to discrete, some time could run out of
MTRRs. So add gran_sizek to prevent that by dumpping small RAM piece less than
gran_sizek.
previous trimming only can handle highest_pfn from mtrr to end_pfn from e820.
when have more than 4g RAM installed, there will be holes below 4g. so need to
check ram below 4g is coverred well.
need to be applied after
[PATCH] x86: mtrr cleanup for converting continuous to discrete layout v7
Signed-off-by: Yinghai Lu <yinghai.lu@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
some BIOS like to use continus MTRR layout, and X driver can not add
WB entries for graphical cards when 4g or more RAM installed.
the patch will change MTRR to discrete.
mtrr_chunk_size= could be used to have smaller continuous block to hold holes.
default is 256m, could be set according to size of graphics card memory.
mtrr_gran_size= could be used to send smallest mtrr block to avoid run out of MTRRs
v2: fix -1 for UC checking
v3: default to disable, and need use enable_mtrr_cleanup to enable this feature
skip the var state change warning.
remove next_basek in range_to_mtrr()
v4: correct warning mask.
v5: CONFIG_MTRR_SANITIZER
v6: fix 1g, 2g, 512 aligment with extra hole
v7: gran_sizek to prevent running out of MTRRs.
v8: fix hole_basek caculation caused when removing next_basek
gran_sizek using when basek is 0.
need to apply
[PATCH] x86: fix trimming e820 with MTRR holes.
right after this one.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
make known_pat_cpu to think amd k8 and fam10h is ok too.
also make tom2 below to be WRBACK
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
fix the bug reported here:
http://bugzilla.kernel.org/show_bug.cgi?id=10232
use update_memory_range() instead of add_memory_range() directly
to avoid closing the gap.
( the new code only affects and runs on systems where the MTRR
workaround triggers. )
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Inside a KVM virtual machine the MTRRs are usually blank. This confuses Linux
and causes a warning message at boot. This patch removes that warning message
when running Linux as a KVM guest.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix mtrr kernel-doc warning:
Warning(linux-2.6.24-git12//arch/x86/kernel/cpu/mtrr/main.c:677): No description found for parameter 'end_pfn'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Pavel Emelyanov reported that his networking card did not work
and bisected it down to:
"
The commit
093af8d7f0
x86_32: trim memory by updating e820
broke my e1000 card: on loading driver says that
e1000: probe of 0000:04:03.0 failed with error -5
and the interface doesn't appear.
"
on a 32-bit kernel, base will overflow when try to do PAGE_SHIFT,
and highest_addr will always less 4G.
So use pfn instead of address to avoid the overflow when more than
4g RAM is installed on a 32-bit kernel.
Many thanks to Pavel Emelyanov for reporting and testing it.
Bisected-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Tested-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
mtrr.h was included everywhere needed. Fixes the following sparse
warnings. Also, the return types in the extern definitions were
incorrect.
arch/x86/kernel/cpu/mtrr/amd.c:113:12: warning: symbol 'amd_init_mtrr' was not declared. Should it be static?
arch/x86/kernel/cpu/mtrr/cyrix.c:268:12: warning: symbol 'cyrix_init_mtrr' was not declared. Should it be static?
arch/x86/kernel/cpu/mtrr/centaur.c:218:12: warning: symbol 'centaur_init_mtrr' was not declared. Should it be static?
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
cyrix_arr_init was #if 0 all the way back to at least v2.6.12.
This was the only place where arr3_protected was set to anything
but zero. Eliminate this variable.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
improve the MTTR trimming messages and also trigger a WARN_ON()
so that kerneloops.org can pick it up and categorize it.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
when MTRRs are not covering the whole e820 table, we need to trim the
RAM and need to update e820.
reuse some code on 64-bit as well.
here need to add early_get_cap and use it in early_cpu_detect, and move
mtrr_bp_init early.
The code successfully trimmed the memory map on Justin's system:
from:
[ 0.000000] BIOS-e820: 0000000100000000 - 000000022c000000 (usable)
to:
[ 0.000000] modified: 0000000100000000 - 0000000228000000 (usable)
[ 0.000000] modified: 0000000228000000 - 000000022c000000 (reserved)
According to Justin it makes quite a difference:
| When I boot the box without any trimming it acts like a 286 or 386,
| takes about 10 minutes to boot (using raptor disks).
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Tested-by: Justin Piszcz <jpiszcz@lucidpixels.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
On some machines, buggy BIOSes don't properly setup WB MTRRs to cover all
available RAM, meaning the last few megs (or even gigs) of memory will be
marked uncached. Since Linux tends to allocate from high memory addresses
first, this causes the machine to be unusably slow as soon as the kernel
starts really using memory (i.e. right around init time).
This patch works around the problem by scanning the MTRRs at boot and
figuring out whether the current end_pfn value (setup by early e820 code)
goes beyond the highest WB MTRR range, and if so, trimming it to match. A
fairly obnoxious KERN_WARNING is printed too, letting the user know that
not all of their memory is available due to a likely BIOS bug.
Something similar could be done on i386 if needed, but the boot ordering
would be slightly different, since the MTRR code on i386 depends on the
boot_cpu_data structure being setup.
This patch fixes a bug in the last patch that caused the code to run on
non-Intel machines (AMD machines apparently don't need it and it's untested
on other non-Intel machines, so best keep it off).
Further enhancements and fixes from:
Yinghai Lu <Yinghai.Lu@Sun.COM>
Andi Kleen <ak@suse.de>
Signed-off-by: Jesse Barnes <jesse.barnes@intel.com>
Tested-by: Justin Piszcz <jpiszcz@lucidpixels.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
H. Peter Anvin