Commit Graph

8502 Commits

Author SHA1 Message Date
Mathias Krause
24ffd84b60 x86/efi: Remove unused efi_call* macros
Complement commit 62fa6e69a4 ("x86/efi: Delete most of the efi_call*
macros") and delete the stub macros for the !CONFIG_EFI case, too. In
fact, there are no EFI calls in this case so we don't need a dummy for
efi_call() even.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-10-03 18:41:02 +01:00
Ard Biesheuvel
161485e827 efi: Implement mandatory locking for UEFI Runtime Services
According to section 7.1 of the UEFI spec, Runtime Services are not fully
reentrant, and there are particular combinations of calls that need to be
serialized. Use a spinlock to serialize all Runtime Services with respect
to all others, even if this is more than strictly needed.

We've managed to get away without requiring a runtime services lock
until now because most of the interactions with EFI involve EFI
variables, and those operations are already serialised with
__efivars->lock.

Some of the assumptions underlying the decision whether locks are
needed or not (e.g., SetVariable() against ResetSystem()) may not
apply universally to all [new] architectures that implement UEFI.
Rather than try to reason our way out of this, let's just implement at
least what the spec requires in terms of locking.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-10-03 18:40:57 +01:00
Pranith Kumar
2291059c85 locking,arch: Use ACCESS_ONCE() instead of cast to volatile in atomic_read()
Use the much more reader friendly ACCESS_ONCE() instead of the cast to volatile.
This is purely a stylistic change.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Link: http://lkml.kernel.org/r/1411482607-20948-1-git-send-email-bobby.prani@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-03 06:06:23 +02:00
Linus Torvalds
cd40fab6db Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "This has:

   - EFI revert to fix a boot regression
   - early_ioremap() fix for boot failure
   - KASLR fix for possible boot failures
   - EFI fix for corrupted string printing
   - remove a misleading EFI bootup 'failed!' error message

  Unfortunately it's all rather close to the merge window"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/efi: Truncate 64-bit values when calling 32-bit OutputString()
  x86/efi: Delete misleading efi_printk() error message
  Revert "efi/x86: efistub: Move shared dependencies to <asm/efi.h>"
  x86/kaslr: Avoid the setup_data area when picking location
  x86 early_ioremap: Increase FIX_BTMAPS_SLOTS to 8
2014-09-27 14:23:13 -07:00
Ingo Molnar
29282ac0bd Merge tag 'efi-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent
Pull EFI fixes from Matt Fleming:

  * Revert the static library changes from the merge window since they're
    causing issues for Macbooks and Fedora + Grub2 (Matt Fleming)

  * Delete the misleading "setup_efi_pci() failed!" message which some
    people are seeing when booting EFI (Matt Fleming)

  * Fix printing strings from the 32-bit EFI boot stub by only passing
    32-bit addresses to the firmware (Matt Fleming)

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-25 16:40:08 +02:00
Tang Chen
c24ae0dcd3 kvm: x86: Unpin and remove kvm_arch->apic_access_page
In order to make the APIC access page migratable, stop pinning it in
memory.

And because the APIC access page is not pinned in memory, we can
remove kvm_arch->apic_access_page.  When we need to write its
physical address into vmcs, we use gfn_to_page() to get its page
struct, which is needed to call page_to_phys(); the page is then
immediately unpinned.

Suggested-by: Gleb Natapov <gleb@kernel.org>
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-24 14:08:01 +02:00
Tang Chen
4256f43f9f kvm: x86: Add request bit to reload APIC access page address
Currently, the APIC access page is pinned by KVM for the entire life
of the guest.  We want to make it migratable in order to make memory
hot-unplug available for machines that run KVM.

This patch prepares to handle this in generic code, through a new
request bit (that will be set by the MMU notifier) and a new hook
that is called whenever the request bit is processed.

Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-24 14:08:00 +02:00
Tang Chen
fe71557afb kvm: Add arch specific mmu notifier for page invalidation
This will be used to let the guest run while the APIC access page is
not pinned.  Because subsequent patches will fill in the function
for x86, place the (still empty) x86 implementation in the x86.c file
instead of adding an inline function in kvm_host.h.

Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-24 14:07:59 +02:00
Andres Lagar-Cavilla
5712846808 kvm: Fix page ageing bugs
1. We were calling clear_flush_young_notify in unmap_one, but we are
within an mmu notifier invalidate range scope. The spte exists no more
(due to range_start) and the accessed bit info has already been
propagated (due to kvm_pfn_set_accessed). Simply call
clear_flush_young.

2. We clear_flush_young on a primary MMU PMD, but this may be mapped
as a collection of PTEs by the secondary MMU (e.g. during log-dirty).
This required expanding the interface of the clear_flush_young mmu
notifier, so a lot of code has been trivially touched.

3. In the absence of shadow_accessed_mask (e.g. EPT A bit), we emulate
the access bit by blowing the spte. This requires proper synchronizing
with MMU notifier consumers, like every other removal of spte's does.

Signed-off-by: Andres Lagar-Cavilla <andreslc@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-24 14:07:58 +02:00
Paolo Bonzini
c1118b3602 x86: kvm: use alternatives for VMCALL vs. VMMCALL if kernel text is read-only
On x86_64, kernel text mappings are mapped read-only with CONFIG_DEBUG_RODATA.
In that case, KVM will fail to patch VMCALL instructions to VMMCALL
as required on AMD processors.

The failure mode is currently a divide-by-zero exception, which obviously
is a KVM bug that has to be fixed.  However, picking the right instruction
between VMCALL and VMMCALL will be faster and will help if you cannot upgrade
the hypervisor.

Reported-by: Chris Webb <chris@arachsys.com>
Tested-by: Chris Webb <chris@arachsys.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-24 14:07:57 +02:00
Liang Chen
77c3913b74 KVM: x86: directly use kvm_make_request again
A one-line wrapper around kvm_make_request is not particularly
useful. Replace kvm_mmu_flush_tlb() with kvm_make_request().

Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-24 14:07:51 +02:00
Matt Fleming
84be880560 Revert "efi/x86: efistub: Move shared dependencies to <asm/efi.h>"
This reverts commit f23cf8bd5c ("efi/x86: efistub: Move shared
dependencies to <asm/efi.h>") as well as the x86 parts of commit
f4f75ad574 ("efi: efistub: Convert into static library").

The road leading to these two reverts is long and winding.

The above two commits were merged during the v3.17 merge window and
turned the common EFI boot stub code into a static library. This
necessitated making some symbols global in the x86 boot stub which
introduced new entries into the early boot GOT.

The problem was that we weren't fixing up the newly created GOT entries
before invoking the EFI boot stub, which sometimes resulted in hangs or
resets. This failure was reported by Maarten on his Macbook pro.

The proposed fix was commit 9cb0e39423 ("x86/efi: Fixup GOT in all
boot code paths"). However, that caused issues for Linus when booting
his Sony Vaio Pro 11. It was subsequently reverted in commit
f3670394c2.

So that leaves us back with Maarten's Macbook pro not booting.

At this stage in the release cycle the least risky option is to revert
the x86 EFI boot stub to the pre-merge window code structure where we
explicitly #include efi-stub-helper.c instead of linking with the static
library. The arm64 code remains unaffected.

We can take another swing at the x86 parts for v3.18.

Conflicts:
	arch/x86/include/asm/efi.h

Tested-by: Josh Boyer <jwboyer@fedoraproject.org>
Tested-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Tested-by: Leif Lindholm <leif.lindholm@linaro.org> [arm64]
Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>,
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-09-23 22:01:55 +01:00
David Vrabel
f955371ca9 x86: remove the Xen-specific _PAGE_IOMAP PTE flag
The _PAGE_IO_MAP PTE flag was only used by Xen PV guests to mark PTEs
that were used to map I/O regions that are 1:1 in the p2m.  This
allowed Xen to obtain the correct PFN when converting the MFNs read
from a PTE back to their PFN.

Xen guests no longer use _PAGE_IOMAP for this. Instead mfn_to_pfn()
returns the correct PFN by using a combination of the m2p and p2m to
determine if an MFN corresponds to a 1:1 mapping in the the p2m.

Remove _PAGE_IOMAP, replacing it with _PAGE_UNUSED2 to allow for
future uses of the PTE flag.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
2014-09-23 13:36:20 +00:00
Zubair Lutfullah Kakakhel
8057b30814 x86: use generic dma-contiguous.h
dma-contiguous.h is now in asm-generic. Use that to avoid code
repetition in x86.

Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: catalin.marinas@arm.com
Cc: will.deacon@arm.com
Cc: tglx@linutronix.de
Cc: mingo@redhat.com
Cc: hpa@zytor.com
Cc: arnd@arndb.de
Cc: gregkh@linuxfoundation.org
Cc: m.szyprowski@samsung.com
Cc: x86@kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-arch@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7359/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-09-22 13:35:52 +02:00
Linus Torvalds
7a5e87867e Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes:

  EFI fixes, a build fix, a page table dumping (debug) fix and a clang
  build fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/arm64: Fix fdt-related memory reservation
  x86/mm: Apply the section attribute to the variable, not its type
  x86/efi: Fixup GOT in all boot code paths
  x86/efi: Only load initrd above 4g on second try
  x86-64, ptdump: Mark espfix area only if existent
  x86, irq: Fix build error caused by 9eabc99a63
2014-09-19 09:07:47 -07:00
Ingo Molnar
43657ffb79 Merge tag 'efi-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent
Pull EFI fix from Matt Fleming:

  * Increase the number of early_ioremap() slots to fix a regression with
    earlyprintk=efi after recent changes to the ACPI code (Dave Young)

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-19 12:49:20 +02:00
Tang Chen
a255d4795f kvm: Remove ept_identity_pagetable from struct kvm_arch.
kvm_arch->ept_identity_pagetable holds the ept identity pagetable page. But
it is never used to refer to the page at all.

In vcpu initialization, it indicates two things:
1. indicates if ept page is allocated
2. indicates if a memory slot for identity page is initialized

Actually, kvm_arch->ept_identity_pagetable_done is enough to tell if the ept
identity pagetable is initialized. So we can remove ept_identity_pagetable.

NOTE: In the original code, ept identity pagetable page is pinned in memroy.
      As a result, it cannot be migrated/hot-removed. After this patch, since
      kvm_arch->ept_identity_pagetable is removed, ept identity pagetable page
      is no longer pinned in memory. And it can be migrated/hot-removed.

Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Reviewed-by: Gleb Natapov <gleb@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-17 13:10:11 +02:00
Luiz Capitulino
8b375f64dc x86/mm/numa: Drop dead code and rename setup_node_data() to setup_alloc_data()
The setup_node_data() function allocates a pg_data_t object,
inserts it into the node_data[] array and initializes the
following fields: node_id, node_start_pfn and
node_spanned_pages.

However, a few function calls later during the kernel boot,
free_area_init_node() re-initializes those fields, possibly with
setup_node_data() is not used.

This causes a small glitch when running Linux as a hyperv numa
guest:

  SRAT: PXM 0 -> APIC 0x00 -> Node 0
  SRAT: PXM 0 -> APIC 0x01 -> Node 0
  SRAT: PXM 1 -> APIC 0x02 -> Node 1
  SRAT: PXM 1 -> APIC 0x03 -> Node 1
  SRAT: Node 0 PXM 0 [mem 0x00000000-0x7fffffff]
  SRAT: Node 1 PXM 1 [mem 0x80200000-0xf7ffffff]
  SRAT: Node 1 PXM 1 [mem 0x100000000-0x1081fffff]
  NUMA: Node 1 [mem 0x80200000-0xf7ffffff] + [mem 0x100000000-0x1081fffff] -> [mem 0x80200000-0x1081fffff]
  Initmem setup node 0 [mem 0x00000000-0x7fffffff]
    NODE_DATA [mem 0x7ffdc000-0x7ffeffff]
  Initmem setup node 1 [mem 0x80800000-0x1081fffff]
    NODE_DATA [mem 0x1081ea000-0x1081fdfff]
  crashkernel: memory value expected
   [ffffea0000000000-ffffea0001ffffff] PMD -> [ffff88007de00000-ffff88007fdfffff] on node 0
   [ffffea0002000000-ffffea00043fffff] PMD -> [ffff880105600000-ffff8801077fffff] on node 1
  Zone ranges:
    DMA      [mem 0x00001000-0x00ffffff]
    DMA32    [mem 0x01000000-0xffffffff]
    Normal   [mem 0x100000000-0x1081fffff]
  Movable zone start for each node
  Early memory node ranges
    node   0: [mem 0x00001000-0x0009efff]
    node   0: [mem 0x00100000-0x7ffeffff]
    node   1: [mem 0x80200000-0xf7ffffff]
    node   1: [mem 0x100000000-0x1081fffff]
  On node 0 totalpages: 524174
    DMA zone: 64 pages used for memmap
    DMA zone: 21 pages reserved
    DMA zone: 3998 pages, LIFO batch:0
    DMA32 zone: 8128 pages used for memmap
    DMA32 zone: 520176 pages, LIFO batch:31
  On node 1 totalpages: 524288
    DMA32 zone: 7672 pages used for memmap
    DMA32 zone: 491008 pages, LIFO batch:31
    Normal zone: 520 pages used for memmap
    Normal zone: 33280 pages, LIFO batch:7

In this dmesg, the SRAT table reports that the memory range for
node 1 starts at 0x80200000.  However, the line starting with
"Initmem" reports that node 1 memory range starts at 0x80800000.
 The "Initmem" line is reported by setup_node_data() and is
wrong, because the kernel ends up using the range as reported in
the SRAT table.

This commit drops all that dead code from setup_node_data(),
renames it to alloc_node_data() and adds a printk() to
free_area_init_node() so that we report a node's memory range
accurately.

Here's the same dmesg section with this patch applied:

   SRAT: PXM 0 -> APIC 0x00 -> Node 0
   SRAT: PXM 0 -> APIC 0x01 -> Node 0
   SRAT: PXM 1 -> APIC 0x02 -> Node 1
   SRAT: PXM 1 -> APIC 0x03 -> Node 1
   SRAT: Node 0 PXM 0 [mem 0x00000000-0x7fffffff]
   SRAT: Node 1 PXM 1 [mem 0x80200000-0xf7ffffff]
   SRAT: Node 1 PXM 1 [mem 0x100000000-0x1081fffff]
   NUMA: Node 1 [mem 0x80200000-0xf7ffffff] + [mem 0x100000000-0x1081fffff] -> [mem 0x80200000-0x1081fffff]
   NODE_DATA(0) allocated [mem 0x7ffdc000-0x7ffeffff]
   NODE_DATA(1) allocated [mem 0x1081ea000-0x1081fdfff]
   crashkernel: memory value expected
    [ffffea0000000000-ffffea0001ffffff] PMD -> [ffff88007de00000-ffff88007fdfffff] on node 0
    [ffffea0002000000-ffffea00043fffff] PMD -> [ffff880105600000-ffff8801077fffff] on node 1
   Zone ranges:
     DMA      [mem 0x00001000-0x00ffffff]
     DMA32    [mem 0x01000000-0xffffffff]
     Normal   [mem 0x100000000-0x1081fffff]
   Movable zone start for each node
   Early memory node ranges
     node   0: [mem 0x00001000-0x0009efff]
     node   0: [mem 0x00100000-0x7ffeffff]
     node   1: [mem 0x80200000-0xf7ffffff]
     node   1: [mem 0x100000000-0x1081fffff]
   Initmem setup node 0 [mem 0x00001000-0x7ffeffff]
   On node 0 totalpages: 524174
     DMA zone: 64 pages used for memmap
     DMA zone: 21 pages reserved
     DMA zone: 3998 pages, LIFO batch:0
     DMA32 zone: 8128 pages used for memmap
     DMA32 zone: 520176 pages, LIFO batch:31
   Initmem setup node 1 [mem 0x80200000-0x1081fffff]
   On node 1 totalpages: 524288
     DMA32 zone: 7672 pages used for memmap
     DMA32 zone: 491008 pages, LIFO batch:31
     Normal zone: 520 pages used for memmap
     Normal zone: 33280 pages, LIFO batch:7

This commit was tested on a two node bare-metal NUMA machine and
Linux as a numa guest on hyperv and qemu/kvm.

PS: The wrong memory range reported by setup_node_data() seems to be
    harmless in the current kernel because it's just not used.  However,
    that bad range is used in kernel 2.6.32 to initialize the old boot
    memory allocator, which causes a crash during boot.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-16 08:55:10 +02:00
Yasuaki Ishimatsu
9661d5bcd0 x86/mm/hotplug: Modify PGD entry when removing memory
When hot-adding/removing memory, sync_global_pgds() is called
for synchronizing PGD to PGD entries of all processes MM.  But
when hot-removing memory, sync_global_pgds() does not work
correctly.

At first, sync_global_pgds() checks whether target PGD is none
or not.  And if PGD is none, the PGD is skipped.  But when
hot-removing memory, PGD may be none since PGD may be cleared by
free_pud_table().  So when sync_global_pgds() is called after
hot-removing memory, sync_global_pgds() should not skip PGD even
if the PGD is none.  And sync_global_pgds() must clear PGD
entries of all processes MM.

Currently sync_global_pgds() does not clear PGD entries of all
processes MM when hot-removing memory.  So when hot adding
memory which is same memory range as removed memory after
hot-removing memory, following call traces are shown:

 kernel BUG at arch/x86/mm/init_64.c:206!
 ...
 [<ffffffff815e0c80>] kernel_physical_mapping_init+0x1b2/0x1d2
 [<ffffffff815ced94>] init_memory_mapping+0x1d4/0x380
 [<ffffffff8104aebd>] arch_add_memory+0x3d/0xd0
 [<ffffffff815d03d9>] add_memory+0xb9/0x1b0
 [<ffffffff81352415>] acpi_memory_device_add+0x1af/0x28e
 [<ffffffff81325dc4>] acpi_bus_device_attach+0x8c/0xf0
 [<ffffffff813413b9>] acpi_ns_walk_namespace+0xc8/0x17f
 [<ffffffff81325d38>] ? acpi_bus_type_and_status+0xb7/0xb7
 [<ffffffff81325d38>] ? acpi_bus_type_and_status+0xb7/0xb7
 [<ffffffff813418ed>] acpi_walk_namespace+0x95/0xc5
 [<ffffffff81326b4c>] acpi_bus_scan+0x9a/0xc2
 [<ffffffff81326bff>] acpi_scan_bus_device_check+0x8b/0x12e
 [<ffffffff81326cb5>] acpi_scan_device_check+0x13/0x15
 [<ffffffff81320122>] acpi_os_execute_deferred+0x25/0x32
 [<ffffffff8107e02b>] process_one_work+0x17b/0x460
 [<ffffffff8107edfb>] worker_thread+0x11b/0x400
 [<ffffffff8107ece0>] ? rescuer_thread+0x400/0x400
 [<ffffffff81085aef>] kthread+0xcf/0xe0
 [<ffffffff81085a20>] ? kthread_create_on_node+0x140/0x140
 [<ffffffff815fc76c>] ret_from_fork+0x7c/0xb0
 [<ffffffff81085a20>] ? kthread_create_on_node+0x140/0x140

This patch clears PGD entries of all processes MM when
sync_global_pgds() is called after hot-removing memory

Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Gu Zheng <guz.fnst@cn.fujitsu.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-16 08:55:09 +02:00
Dave Young
3eddc69ffe x86 early_ioremap: Increase FIX_BTMAPS_SLOTS to 8
3.16 kernel boot fail with earlyprintk=efi, it keeps scrolling at the
bottom line of screen.

Bisected, the first bad commit is below:
commit 86dfc6f339
Author: Lv Zheng <lv.zheng@intel.com>
Date:   Fri Apr 4 12:38:57 2014 +0800

    ACPICA: Tables: Fix table checksums verification before installation.

I did some debugging by enabling both serial and efi earlyprintk, below is
some debug dmesg, seems early_ioremap fails in scroll up function due to
no free slot, see below dmesg output:

  WARNING: CPU: 0 PID: 0 at mm/early_ioremap.c:116 __early_ioremap+0x90/0x1c4()
  __early_ioremap(ed00c800, 00000c80) not found slot
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper Not tainted 3.17.0-rc1+ #204
  Hardware name: Hewlett-Packard HP Z420 Workstation/1589, BIOS J61 v03.15 05/09/2013
  Call Trace:
    dump_stack+0x4e/0x7a
    warn_slowpath_common+0x75/0x8e
    ? __early_ioremap+0x90/0x1c4
    warn_slowpath_fmt+0x47/0x49
    __early_ioremap+0x90/0x1c4
    ? sprintf+0x46/0x48
    early_ioremap+0x13/0x15
    early_efi_map+0x24/0x26
    early_efi_scroll_up+0x6d/0xc0
    early_efi_write+0x1b0/0x214
    call_console_drivers.constprop.21+0x73/0x7e
    console_unlock+0x151/0x3b2
    ? vprintk_emit+0x49f/0x532
    vprintk_emit+0x521/0x532
    ? console_unlock+0x383/0x3b2
    printk+0x4f/0x51
    acpi_os_vprintf+0x2b/0x2d
    acpi_os_printf+0x43/0x45
    acpi_info+0x5c/0x63
    ? __acpi_map_table+0x13/0x18
    ? acpi_os_map_iomem+0x21/0x147
    acpi_tb_print_table_header+0x177/0x186
    acpi_tb_install_table_with_override+0x4b/0x62
    acpi_tb_install_standard_table+0xd9/0x215
    ? early_ioremap+0x13/0x15
    ? __acpi_map_table+0x13/0x18
    acpi_tb_parse_root_table+0x16e/0x1b4
    acpi_initialize_tables+0x57/0x59
    acpi_table_init+0x50/0xce
    acpi_boot_table_init+0x1e/0x85
    setup_arch+0x9b7/0xcc4
    start_kernel+0x94/0x42d
    ? early_idt_handlers+0x120/0x120
    x86_64_start_reservations+0x2a/0x2c
    x86_64_start_kernel+0xf3/0x100

Quote reply from Lv.zheng about the early ioremap slot usage in this case:

"""
In early_efi_scroll_up(), 2 mapping entries will be used for the src/dst screen buffer.
In drivers/acpi/acpica/tbutils.c, we've improved the early table loading code in acpi_tb_parse_root_table().
We now need 2 mapping entries:
1. One mapping entry is used for RSDT table mapping. Each RSDT entry contains an address for another ACPI table.
2. For each entry in RSDP, we need another mapping entry to map the table to perform necessary check/override before installing it.

When acpi_tb_parse_root_table() prints something through EFI earlyprintk console, we'll have 4 mapping entries used.
The current 4 slots setting of early_ioremap() seems to be too small for such a use case.
"""

Thus increase the slot to 8 in this patch to fix this issue.
boot-time mappings become 512 page with this patch.

Signed-off-by: Dave Young <dyoung@redhat.com>
Cc: <stable@vger.kernel.org> # v3.16
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-09-14 15:24:31 +01:00
Linus Torvalds
72d9310460 Make ARCH_HAS_FAST_MULTIPLIER a real config variable
It used to be an ad-hoc hack defined by the x86 version of
<asm/bitops.h> that enabled a couple of library routines to know whether
an integer multiply is faster than repeated shifts and additions.

This just makes it use the real Kconfig system instead, and makes x86
(which was the only architecture that did this) select the option.

NOTE! Even for x86, this really is kind of wrong.  If we cared, we would
probably not enable this for builds optimized for netburst (P4), where
shifts-and-adds are generally faster than multiplies.  This patch does
*not* change that kind of logic, though, it is purely a syntactic change
with no code changes.

This was triggered by the fact that we have other places that really
want to know "do I want to expand multiples by constants by hand or
not", particularly the hash generation code.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-09-13 11:14:53 -07:00
Frederic Weisbecker
3010279f0f x86: Tell irq work about self IPI support
x86 supports irq work self-IPIs when local apic is available. This is
partly known on runtime so lets implement arch_irq_work_has_interrupt()
accordingly.

This should be safely called after setup_arch().

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2014-09-13 18:38:29 +02:00
Peter Zijlstra
c5c38ef3d7 irq_work: Introduce arch_irq_work_has_interrupt()
The nohz full code needs irq work to trigger its own interrupt so that
the subsystem can work even when the tick is stopped.

Lets introduce arch_irq_work_has_interrupt() that archs can override to
tell about their support for this ability.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2014-09-13 18:38:07 +02:00
Linus Torvalds
7ee2d2d671 Merge tag 'stable/for-linus-3.17-b-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull Xen bug fixes from David Vrabel:
 - fix for PVHVM suspend/resume and migration
 - don't pointlessly retry certain ballooning ops
 - fix gntalloc when grefs have run out.
 - fix PV boot if KSALR is enable or very large modules are used.

* tag 'stable/for-linus-3.17-b-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: don't copy bogus duplicate entries into kernel page tables
  xen/gntalloc: safely delete grefs in add_grefs() undo path
  xen/gntalloc: fix oops after runnning out of grant refs
  xen/balloon: cancel ballooning if adding new memory failed
  xen/manage: Always freeze/thaw processes when suspend/resuming
2014-09-11 16:52:29 -07:00
Dave Hansen
9298b815ef x86: Add more disabled features
The original motivation for these patches was for an Intel CPU
feature called MPX.  The patch to add a disabled feature for it
will go in with the other parts of the support.

But, in the meantime, there are a few other features than MPX
that we can make assumptions about at compile-time based on
compile options.  Add them to disabled-features.h and check them
with cpu_feature_enabled().

Note that this gets rid of the last things that needed an #ifdef
CONFIG_X86_64 in cpufeature.h.  Yay!

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/r/20140911211524.C0EC332A@viggo.jf.intel.com
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-09-11 14:30:17 -07:00
Dave Hansen
381aa07a9b x86: Introduce disabled-features
I believe the REQUIRED_MASK aproach was taken so that it was
easier to consult in assembly (arch/x86/kernel/verify_cpu.S).
DISABLED_MASK does not have the same restriction, but I
implemented it the same way for consistency.

We have a REQUIRED_MASK... which does two things:
1. Keeps a list of cpuid bits to check in very early boot and
   refuse to boot if those are not present.
2. Consulted during cpu_has() checks, which allows us to
   optimize out things at compile-time.  In other words, if we
   *KNOW* we will not boot with the feature off, then we can
   safely assume that it will be present forever.

But, we don't have a similar mechanism for CPU features which
may be present but that we know we will not use.  We simply
use our existing mechanisms to repeatedly check the status of
the bit at runtime (well, the alternatives patching helps here
but it does not provide compile-time optimization).

Adding a feature to disabled-features.h allows the bit to be
checked via a new macro: cpu_feature_enabled().  Note that
for features in DISABLED_MASK, checks with this macro have
all of the benefits of an #ifdef.  Before, we would have done
this in a header:

#ifdef CONFIG_X86_INTEL_MPX
#define cpu_has_mpx cpu_has(X86_FEATURE_MPX)
#else
#define cpu_has_mpx 0
#endif

and this in the code:

	if (cpu_has_mpx)
		do_some_mpx_thing();

Now, just add your feature to DISABLED_MASK and you can do this
everywhere, and get the same benefits you would have from
#ifdefs:

	if (cpu_feature_enabled(X86_FEATURE_MPX))
		do_some_mpx_thing();

We need a new function and *not* a modification to cpu_has()
because there are cases where we actually need to check the CPU
itself, despite what features the kernel supports.  The best
example of this is a hypervisor which has no control over what
features its guests are using and where the guest does not depend
on the host for support.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/r/20140911211513.9E35E931@viggo.jf.intel.com
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-09-11 14:30:02 -07:00
Dave Hansen
c8128cceb4 x86: Axe the lightly-used cpu_has_pae
cpu_has_pae is only referenced in one place: the X86_32 kexec
code (in a file not even built on 64-bit).  It hardly warrants
its own macro, or the trouble we go to ensuring that it can't
be called in X86_64 code.

Axe the macro and replace it with a direct cpu feature check.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/r/20140911211511.AD76E774@viggo.jf.intel.com
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-09-11 14:30:01 -07:00
Stefan Bader
0b5a50635f x86/xen: don't copy bogus duplicate entries into kernel page tables
When RANDOMIZE_BASE (KASLR) is enabled; or the sum of all loaded
modules exceeds 512 MiB, then loading modules fails with a warning
(and hence a vmalloc allocation failure) because the PTEs for the
newly-allocated vmalloc address space are not zero.

  WARNING: CPU: 0 PID: 494 at linux/mm/vmalloc.c:128
           vmap_page_range_noflush+0x2a1/0x360()

This is caused by xen_setup_kernel_pagetables() copying
level2_kernel_pgt into level2_fixmap_pgt, overwriting many non-present
entries.

Without KASLR, the normal kernel image size only covers the first half
of level2_kernel_pgt and module space starts after that.

L4[511]->level3_kernel_pgt[510]->level2_kernel_pgt[  0..255]->kernel
                                                  [256..511]->module
                          [511]->level2_fixmap_pgt[  0..505]->module

This allows 512 MiB of of module vmalloc space to be used before
having to use the corrupted level2_fixmap_pgt entries.

With KASLR enabled, the kernel image uses the full PUD range of 1G and
module space starts in the level2_fixmap_pgt. So basically:

L4[511]->level3_kernel_pgt[510]->level2_kernel_pgt[0..511]->kernel
                          [511]->level2_fixmap_pgt[0..505]->module

And now no module vmalloc space can be used without using the corrupt
level2_fixmap_pgt entries.

Fix this by properly converting the level2_fixmap_pgt entries to MFNs,
and setting level1_fixmap_pgt as read-only.

A number of comments were also using the the wrong L3 offset for
level2_kernel_pgt.  These have been corrected.

Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: stable@vger.kernel.org
2014-09-10 15:23:42 +01:00
Waiman Long
6157c7e1bb locking/rwlock, x86: Delete unused asm/rwlock.h and rwlock.S
This patch removes the unused asm/rwlock.h and rwlock.S files.

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1408037251-45918-3-git-send-email-Waiman.Long@hp.com
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Francesco Fusco <ffusco@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Graf <tgraf@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-10 11:46:39 +02:00
Waiman Long
2ff810a7ef locking/rwlock, x86: Clean up asm/spinlock*.h to remove old rwlock code
As the x86 architecture now uses qrwlock for its read/write lock
implementation, it is no longer necessary to keep the old rwlock code
around. This patch removes the old rwlock code in the asm/spinlock.h
and asm/spinlock_types.h files. Now the ARCH_USE_QUEUE_RWLOCK
config parameter cannot be removed from x86/Kconfig or there will be
a compilation error.

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Waiman Long <Waiman.Long@hp.com>
Link: http://lkml.kernel.org/r/1408037251-45918-2-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-10 11:46:38 +02:00
Ingo Molnar
bdea534db8 Merge tag 'v3.17-rc4' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-09 06:48:07 +02:00
Andy Lutomirski
54eea9957f x86_64, entry: Treat regs->ax the same in fastpath and slowpath syscalls
For slowpath syscalls, we initialize regs->ax to -ENOSYS and stick
the syscall number into regs->orig_ax prior to any possible tracing
and syscall execution.  This is user-visible ABI used by ptrace
syscall emulation and seccomp.

For fastpath syscalls, there's no good reason not to do the same
thing.  It's even slightly simpler than what we're currently doing.
It probably has no measureable performance impact.  It should have
no user-visible effect.

The purpose of this patch is to prepare for two-phase syscall
tracing, in which the first phase might modify the saved RAX without
leaving the fast path.  This change is just subtle enough that I'm
keeping it separate.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/01218b493f12ae2f98034b78c9ae085e38e94350.1409954077.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-09-08 14:14:08 -07:00
Andy Lutomirski
e0ffbaabc4 x86: Split syscall_trace_enter into two phases
This splits syscall_trace_enter into syscall_trace_enter_phase1 and
syscall_trace_enter_phase2.  Only phase 2 has full pt_regs, and only
phase 2 is permitted to modify any of pt_regs except for orig_ax.

The intent is that phase 1 can be called from the syscall fast path.

In this implementation, phase1 can handle any combination of
TIF_NOHZ (RCU context tracking), TIF_SECCOMP, and TIF_SYSCALL_AUDIT,
unless seccomp requests a ptrace event, in which case phase2 is
forced.

In principle, this could yield a big speedup for TIF_NOHZ as well as
for TIF_SECCOMP if syscall exit work were similarly split up.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/2df320a600020fda055fccf2b668145729dd0c04.1409954077.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-09-08 14:14:03 -07:00
Ingo Molnar
196cf35842 x86/tty/serial/8250: Clean up the asm/serial.h include file a bit
- correct spelling
 - align fields vertically to make things more readable
 - make the layout of magic defines more obvious

Cc: Mark Rustad <mark.d.rustad@intel.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Link: http://lkml.kernel.org/r/1409972149-26272-1-git-send-email-jeffrey.t.kirsher@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-06 10:20:55 +02:00
Mark Rustad
9ea029f12a x86/tty/serial/8250: Resolve missing-field-initializers warnings
Resolve some missing-field-initializers warnings by using
designated initialization in the expansion of the
SERIAL_PORT_DFNS macro.

Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Link: http://lkml.kernel.org/r/1409972149-26272-1-git-send-email-jeffrey.t.kirsher@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-06 10:20:53 +02:00
Paolo Bonzini
54987b7afa KVM: x86: propagate exception from permission checks on the nested page fault
Currently, if a permission error happens during the translation of
the final GPA to HPA, walk_addr_generic returns 0 but does not fill
in walker->fault.  To avoid this, add an x86_exception* argument
to the translate_gpa function, and let it fill in walker->fault.
The nested_page_fault field will be true, since the walk_mmu is the
nested_mmu and translate_gpu instead operates on the "outer" (NPT)
instance.

Reported-by: Valentine Sinitsyn <valentine.sinitsyn@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-05 12:01:13 +02:00
Paolo Bonzini
ef54bcfeea KVM: x86: skip writeback on injection of nested exception
If a nested page fault happens during emulation, we will inject a vmexit,
not a page fault.  However because writeback happens after the injection,
we will write ctxt->eip from L2 into the L1 EIP.  We do not write back
if an instruction caused an interception vmexit---do the same for page
faults.

Suggested-by: Gleb Natapov <gleb@kernel.org>
Reviewed-by: Gleb Natapov <gleb@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-05 12:01:06 +02:00
David Matlack
56f17dd3fb kvm: x86: fix stale mmio cache bug
The following events can lead to an incorrect KVM_EXIT_MMIO bubbling
up to userspace:

(1) Guest accesses gpa X without a memory slot. The gfn is cached in
struct kvm_vcpu_arch (mmio_gfn). On Intel EPT-enabled hosts, KVM sets
the SPTE write-execute-noread so that future accesses cause
EPT_MISCONFIGs.

(2) Host userspace creates a memory slot via KVM_SET_USER_MEMORY_REGION
covering the page just accessed.

(3) Guest attempts to read or write to gpa X again. On Intel, this
generates an EPT_MISCONFIG. The memory slot generation number that
was incremented in (2) would normally take care of this but we fast
path mmio faults through quickly_check_mmio_pf(), which only checks
the per-vcpu mmio cache. Since we hit the cache, KVM passes a
KVM_EXIT_MMIO up to userspace.

This patch fixes the issue by using the memslot generation number
to validate the mmio cache.

Cc: stable@vger.kernel.org
Signed-off-by: David Matlack <dmatlack@google.com>
[xiaoguangrong: adjust the code to make it simpler for stable-tree fix.]
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Tested-by: David Matlack <dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-03 10:03:42 +02:00
Oleg Nesterov
31d963389f x86, fpu: Change __thread_fpu_begin() to use use_eager_fpu()
__thread_fpu_begin() checks X86_FEATURE_EAGER_FPU by hand, we have
a helper for that.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20140902175720.GA21656@redhat.com
Reviewed-by: Suresh Siddha <sbsiddha@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-09-02 14:51:15 -07:00
Matthew Wilcox
bb693f13a0 x86: Remove set_pmd_pfn
The last user of set_pmd_pfn() went away in commit f03574f2d5, so this
has been dead code for over a year.

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

 arch/x86/include/asm/pgtable_32.h |    3 ---
 arch/x86/mm/pgtable_32.c          |   35 -----------------------------------
 2 files changed, 38 deletions(-)
2014-09-01 10:15:31 +02:00
Jiang Liu
f3761db164 x86, irq: Fix build error caused by 9eabc99a63
Commit 9eabc99a63 causes following build error when
IOAPIC is disabled.
   arch/x86/pci/irq.c: In function 'pirq_disable_irq':
>> arch/x86/pci/irq.c:1259:2: error: implicit declaration of function 'mp_should_keep_irq' [-Werror=implicit-function-declaration]
     if (io_apic_assign_pci_irqs && !mp_should_keep_irq(&dev->dev) &&
     ^
   cc1: some warnings being treated as errors

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Grant Likely <grant.likely@linaro.org>
Link: http://lkml.kernel.org/r/1409382916-10649-1-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-09-01 10:12:03 +02:00
Linus Torvalds
fd5984d7c8 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Peter Anvin:
 "One patch to avoid assigning interrupts we don't actually have on
  non-PC platforms, and two patches that addresses bugs in the new
  IOAPIC assignment code"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, irq, PCI: Keep IRQ assignment for runtime power management
  x86: irq: Fix bug in setting IOAPIC pin attributes
  x86: Fix non-PC platform kernel crash on boot due to NULL dereference
2014-08-29 17:22:27 -07:00
Hugh Dickins
b38af4721f x86,mm: fix pte_special versus pte_numa
Sasha Levin has shown oopses on ffffea0003480048 and ffffea0003480008 at
mm/memory.c:1132, running Trinity on different 3.16-rc-next kernels:
where zap_pte_range() checks page->mapping to see if PageAnon(page).

Those addresses fit struct pages for pfns d2001 and d2000, and in each
dump a register or a stack slot showed d2001730 or d2000730: pte flags
0x730 are PCD ACCESSED PROTNONE SPECIAL IOMAP; and Sasha's e820 map has
a hole between cfffffff and 100000000, which would need special access.

Commit c46a7c817e ("x86: define _PAGE_NUMA by reusing software bits on
the PMD and PTE levels") has broken vm_normal_page(): a PROTNONE SPECIAL
pte no longer passes the pte_special() test, so zap_pte_range() goes on
to try to access a non-existent struct page.

Fix this by refining pte_special() (SPECIAL with PRESENT or PROTNONE) to
complement pte_numa() (SPECIAL with neither PRESENT nor PROTNONE).  A
hint that this was a problem was that c46a7c817e added pte_numa() test
to vm_normal_page(), and moved its is_zero_pfn() test from slow to fast
path: This was papering over a pte_special() snag when the zero page was
encountered during zap.  This patch reverts vm_normal_page() to how it
was before, relying on pte_special().

It still appears that this patch may be incomplete: aren't there other
places which need to be handling PROTNONE along with PRESENT?  For
example, pte_mknuma() clears _PAGE_PRESENT and sets _PAGE_NUMA, but on a
PROT_NONE area, that would make it pte_special().  This is side-stepped
by the fact that NUMA hinting faults skipped PROT_NONE VMAs and there
are no grounds where a NUMA hinting fault on a PROT_NONE VMA would be
interesting.

Fixes: c46a7c817e ("x86: define _PAGE_NUMA by reusing software bits on the PMD and PTE levels")
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: <stable@vger.kernel.org>	[3.16]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-29 16:28:16 -07:00
Radim Krčmář
13a34e067e KVM: remove garbage arg to *hardware_{en,dis}able
In the beggining was on_each_cpu(), which required an unused argument to
kvm_arch_ops.hardware_{en,dis}able, but this was soon forgotten.

Remove unnecessary arguments that stem from this.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-29 16:35:55 +02:00
Paolo Bonzini
656473003b KVM: forward declare structs in kvm_types.h
Opaque KVM structs are useful for prototypes in asm/kvm_host.h, to avoid
"'struct foo' declared inside parameter list" warnings (and consequent
breakage due to conflicting types).

Move them from individual files to a generic place in linux/kvm_types.h.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-29 16:35:53 +02:00
Jiang Liu
9eabc99a63 x86, irq, PCI: Keep IRQ assignment for runtime power management
Now IOAPIC driver dynamically allocates IRQ numbers for IOAPIC pins.
We need to keep IRQ assignment for PCI devices during runtime power
management, otherwise it may cause failure of device wakeups.

Commit 3eec595235 "x86, irq, PCI: Keep IRQ assignment for PCI
devices during suspend/hibernation" has fixed the issue for suspend/
hibernation, we also need the same fix for runtime device sleep too.

Fix: https://bugzilla.kernel.org/show_bug.cgi?id=83271
Reported-and-Tested-by: EmanueL Czirai <amanual@openmailbox.org>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: EmanueL Czirai <amanual@openmailbox.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Grant Likely <grant.likely@linaro.org>
Link: http://lkml.kernel.org/r/1409304383-18806-1-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-08-29 13:38:00 +02:00
Christoph Lameter
4ba2968420 percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t
__get_cpu_var can paper over differences in the definitions of
cpumask_var_t and either use the address of the cpumask variable
directly or perform a fetch of the address of the struct cpumask
allocated elsewhere. This is important particularly when using per cpu
cpumask_var_t declarations because in one case we have an offset into
a per cpu area to handle and in the other case we need to fetch a
pointer from the offset.

This patch introduces a new macro

this_cpu_cpumask_var_ptr()

that is defined where cpumask_var_t is defined and performs the proper
actions. All use cases where __get_cpu_var is used with cpumask_var_t
are converted to the use of this_cpu_cpumask_var_ptr().

Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-28 08:58:57 -04:00
Christoph Lameter
e16321709c uv: Replace __get_cpu_var
Use __this_cpu_read instead.

Cc: Hedi Berriche <hedi@sgi.com>
Cc: Mike Travis <travis@sgi.com>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-26 13:45:50 -04:00
Christoph Lameter
89cbc76768 x86: Replace __get_cpu_var uses
__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x).  This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.

Other use cases are for storing and retrieving data from the current
processors percpu area.  __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.

__get_cpu_var() is defined as :

#define __get_cpu_var(var) (*this_cpu_ptr(&(var)))

__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.

this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.

This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset.  Thereby address calculations are avoided and less registers
are used when code is generated.

Transformations done to __get_cpu_var()

1. Determine the address of the percpu instance of the current processor.

	DEFINE_PER_CPU(int, y);
	int *x = &__get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(&y);

2. Same as #1 but this time an array structure is involved.

	DEFINE_PER_CPU(int, y[20]);
	int *x = __get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(y);

3. Retrieve the content of the current processors instance of a per cpu
variable.

	DEFINE_PER_CPU(int, y);
	int x = __get_cpu_var(y)

   Converts to

	int x = __this_cpu_read(y);

4. Retrieve the content of a percpu struct

	DEFINE_PER_CPU(struct mystruct, y);
	struct mystruct x = __get_cpu_var(y);

   Converts to

	memcpy(&x, this_cpu_ptr(&y), sizeof(x));

5. Assignment to a per cpu variable

	DEFINE_PER_CPU(int, y)
	__get_cpu_var(y) = x;

   Converts to

	__this_cpu_write(y, x);

6. Increment/Decrement etc of a per cpu variable

	DEFINE_PER_CPU(int, y);
	__get_cpu_var(y)++

   Converts to

	__this_cpu_inc(y)

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-26 13:45:49 -04:00
Ingo Molnar
83bc90e115 Merge branch 'linus' into perf/core, to fix conflicts
Conflicts:
	arch/x86/kernel/cpu/perf_event_intel_uncore*.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-24 22:32:24 +02:00