CPU hotplug fills up the possible map to NR_CPUs, but it did that after
setting up per CPU data. This lead to CPU data not getting allocated
for all possible CPUs, which lead to various side effects.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch makes swsusp avoid the possible temporary corruption
of page translation tables during resume on x86-64. This is achieved by
creating a copy of the relevant page tables that will not be modified by
swsusp and can be safely used by it on resume.
The problem is that during resume on x86-64 swsusp may temporarily
corrupt the page tables used for the direct mapping of RAM. If that
happens, a page fault occurs and cannot be handled properly, which leads
to the solid hang of the affected system. This leads to the loss of the
system's state from before suspend and may result in the loss of data or
the corruption of filesystems, so it is a serious issue. Also, it
appears to happen quite often (for me, as often as 50% of the time).
The problem is related to the fact that (at least) one of the PMD
entries used in the direct memory mapping (starting at PAGE_OFFSET)
points to a page table the physical address of which is much greater
than the physical address of the PMD entry itself. Moreover,
unfortunately, the physical address of the page table before suspend
(i.e. the one stored in the suspend image) happens to be different to
the physical address of the corresponding page table used during resume
(i.e. the one that is valid right before swsusp_arch_resume() in
arch/x86_64/kernel/suspend_asm.S is executed). Thus while the image is
restored, the "offending" PMD entry gets overwritten, so it does not
point to the right physical address any more (i.e. there's no page
table at the address pointed to by it, because it points to the address
the page table has been at during suspend). Consequently, if the PMD
entry is used later on, and it _is_ used in the process of copying the
image pages, a page fault occurs, but it cannot be handled in the normal
way and the system hangs.
In principle we can call create_resume_mapping() from
swsusp_arch_resume() (ie. from suspend_asm.S), but then the memory
allocations in create_resume_mapping(), resume_pud_mapping(), and
resume_pmd_mapping() must be made carefully so that we use _only_
NosaveFree pages in them (the other pages are overwritten by the loop in
swsusp_arch_resume()). Additionally, we are in atomic context at that
time, so we cannot use GFP_KERNEL. Moreover, if one of the allocations
fails, we should free all of the allocated pages, so we need to trace
them somehow.
All of this is done in the appended patch, except that the functions
populating the page tables are located in arch/x86_64/kernel/suspend.c
rather than in init.c. It may be done in a more elegan way in the
future, with the help of some swsusp patches that are in the works now.
[AK: move some externs into headers, renamed a function]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Drop global bit from early low mappings
Suggested by Linus, originally also proposed by Suresh.
This fixes a race condition with early start of udev, originally
tracked down by Suresh B. Siddha. The problem was that switching
to the user space VM would not clear the global low mappings
for the beginning of memory, which lead to memory corruption.
Drop the global bits.
The kernel mapping stays global because it should stay constant.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2.6.14-rc2 does not assign cpus to proper nodeids on our em64t numa boxen.
Our boxes use acpi srat for parsing the numa information.
srat_detect_node() used phys_proc_id[] to get to the cpu's local apic id,
but phys_proc_id[] represents the cpu<->initial_apic_id mapping. The
following patch fixes this problem. Now apicid_to_node[] is properly
indexed with the local apic id.
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The up()/down() orders are incorrect in arch/x86_64/kprobes.c file.
kprobe_mutext is used to protect the free kprobe instruction slot list.
arch_prepare_kprobe applies for a slot from the free list, and
arch_remove_kprobe returns a slot to the free list. The incorrect up()/down()
orders to operate on kprobe_mutex fail to protect the free list. If 2 threads
try to get/return kprobe instruction slot at the same time, the free slot list
might be broken, or a free slot might be applied by 2 threads.
Signed-off-by: Zhang Yanmin <Yanmin.zhang@intel.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The attempt to fixup the lockless mce log buffer introduced an infinite loop
when trying to find a free entry.
And:
Using rcu_dereference() to load mcelog.next doesn't seem to be sufficient
enough to ensure that mcelog.next is loaded each time around the loop in
mce_log(). Instead, use an explicit rmb() to ensure that the compiler gets it
right.
AK: turned the smp_wmbs into true wmbs to make sure they are not
reordered by the compiler on UP.
Signed-off-by: Mike Waychison <mikew@google.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I checked with AMD and they requested to only disable it for family 15.
Also disable it for i386 too. And some style fixes.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This should resolve the issue seen in bugme bug #5105, where it is assumed
that dualcore x86_64 systems have synced TSCs. This is not the case, and
alternate timesources should be used instead.
For more details, see:
http://bugzilla.kernel.org/show_bug.cgi?id=5105
Andi's earlier concerns that the TSCs should be synced on dualcore systems
have been resolved by confirmation from AMD folks that they can be
unsynced.
Acked-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
They seem to have been due to AMD errata 63/122; the fix is to disable
TLB flush filtering in SMP configurations.
Confirmed to fix the problem by Andrew Walrond <andrew@walrond.org>
[ Let's see if we'll have a better fix eventually, this is the Q&D
"let's get this fixed and out there" version ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Several implementations were essentialy a common piece of C code using
the cmpxchg() macro. Put the implementation in one spot that everyone
can share, and convert sparc64 over to using this.
Alpha is the lone arch-specific implementation, which codes up a
special fast path for the common case in order to avoid GP reloading
which a pure C version would require.
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 66759a01ad introduced the fix for
time ticking too fast on some boards by disabling one of the doubly
connected timer pins on ATI boards.
However, it ends up being _much_ too broad a brush, and that just makes
some other ATI boards not work at all since they now have no timer
source.
So disable the automatic ATI southbridge detection, and just rely on
people who see this problem disabling it by hand with the option
"disable_timer_pin_1" on the kernel command line.
Maybe somebody can figure out the proper tests at a later date.
Acked-by: Peter Osterlund <petero2@telia.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Like previously done for i386, get the x86_64 watchdog tick calculation
into a state where it can also be used on CPUs with frequencies beyond
4GHz.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the add_taint() interface for setting tainted bit flags instead of
doing it manually.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Original patch from Bertro Simul
This is probably still not quite correct, but seems to be
the best solution so far.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As mentioned before, the size of the bug frame can be further reduced while
continuing to use instructions to encode the information.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
... and with that all instances in arch/x86_64 are gone.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is the same patch that went into i386 just before 2.6.13
came out. I still can't build 64-bit user apps, so I tested
with program (see below) in 32-bit mode on 64-bit kernel:
Before:
$ fpsig
handler: nr = 8, si = 0x0804bc90, vuc = 0x0804bd10
handler: altstack is at 0x0804b000, ebp = 0x0804bc7c
handler: si_signo = 8, si_errno = 0, si_code = 0 [unknown]
handler: fpu cwd = 0xb40, fpu swd = 0xbaa0
handler: i387 unmasked precision exception, rounded up
After:
$ fpsig
handler: nr = 8, si = 0x0804bc90, vuc = 0x0804bd10
handler: altstack is at 0x0804b000, ebp = 0x0804bc7c
handler: si_signo = 8, si_errno = 0, si_code = 6 [inexact result]
handler: fpu cwd = 0xb40, fpu swd = 0xbaa0
handler: i387 unmasked precision exception, rounded up
Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The x86_64 nmi code is missing a newline in one of its messages.
I added a space before the CPU id for readability and killed the trailing
space on the previous line as well.
Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Rather than blindly re-enabling interrupts in oops_end(), save their state
in oope_begin() and then restore that state.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The only difference was the inline assembly, so move that into
asm/msr.h and merge with the i386 version.
This adds some missing sysfs support code to x86-64.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Being the foundation for reliable stack unwinding, this fixes CFI unwind
annotations in many low-level x86_64 routines, plus a config option
(available to all architectures, and also present in the previously sent
patch adding such annotations to i386 code) to enable them separatly
rather than only along with adding full debug information.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Nick points out it never worked because PageReserved was
set and it might cause problems later on. Also HOTPLUG_CPU
is much more common now so let's care not too much
about the !hotplug case.
Cc: nickpiggin@yahoo.com.au
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It only offers extremly dubious security advantages and
is not worth the overhead in this critical path.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The global bit was not set in the first 2MB page, instead
it had a bit in the free AVL section which is useless.
Fixed thus.
Noticed by Eric Biederman
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
x86_64 idle=poll might be a little less responsive than it should: unlike
mwait_idle, and unlike i386, its poll_idle left TIF_POLLING_NRFLAG set.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adds console and earlyprintk support for a host file
on AMD's SimNow simulator.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Instead of using a global spinlock to protect the state
of the remote TLB flush use a lock and state for each sending CPU.
To tell the receiver where to look for the state use 8 different
call vectors. Each CPU uses a specific vector to trigger flushes on other
CPUs. Depending on the received vector the target CPUs look into
the right per cpu variable for the flush data.
When the system has more than 8 CPUs they are hashed to the 8 available
vectors. The limited global vector space forces us to this right now.
In future when interrupts are split into per CPU domains this could be
fixed, at the cost of needing more IPIs in flat mode.
Also some minor cleanup in the smp flush code and remove some outdated
debug code.
Requires patch to move cpu_possible_map setup earlier.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Include build number in oops output
Helps me to match oopses to correct kernel.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The resume code uses CPU hotplug now so at resume time
we only ever see one CPU.
Pointed out by Yu Luming.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It could be wrong for kexec or other cases. Read it from
the CPU instead.
Signed-off-by: Murali <muralim@in.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
One machine is constantly throwing NMI watchdog timeouts in mce_log
This was one attempt to fix it.
(AK: this doesn't actually fix the bug I'm seeing unfortunately, probably
drop. I don't like it that the reader can spin forever now waiting
for a writer)
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Originally from Stuart Hayes.
When setting up the APIC for the Uniprocessor kernel don't
assume the CPU has an APIC ID of zero.
This fixes boot with the UP kernel on Dell PowerEdge 6800/6850 4way systems.
Cc: Stuart.Hayes@dell.com
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Al Viro