Switch to pr_debug() so that dynamic-debug can disable these messages by
default. This gets noisy in the presence of devm_memremap_pages().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Warn on any residual W+X mappings after setting NX
if DEBUG_WX is enabled. Introduce a separate
X86_PTDUMP_CORE config that enables the code for
dumping the page tables without enabling the debugfs
interface, so that DEBUG_WX can be enabled without
exposing the debugfs interface. Switch EFI_PGT_DUMP
to using X86_PTDUMP_CORE so that it also does not require
enabling the debugfs interface.
On success it prints this to the kernel log:
x86/mm: Checked W+X mappings: passed, no W+X pages found.
On failure it prints a warning and a count of the failed pages:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 1 at arch/x86/mm/dump_pagetables.c:226 note_page+0x610/0x7b0()
x86/mm: Found insecure W+X mapping at address ffffffff81755000/__stop___ex_table+0xfa8/0xabfa8
[...]
Call Trace:
[<ffffffff81380a5f>] dump_stack+0x44/0x55
[<ffffffff8109d3f2>] warn_slowpath_common+0x82/0xc0
[<ffffffff8109d48c>] warn_slowpath_fmt+0x5c/0x80
[<ffffffff8106cfc9>] ? note_page+0x5c9/0x7b0
[<ffffffff8106d010>] note_page+0x610/0x7b0
[<ffffffff8106d409>] ptdump_walk_pgd_level_core+0x259/0x3c0
[<ffffffff8106d5a7>] ptdump_walk_pgd_level_checkwx+0x17/0x20
[<ffffffff81063905>] mark_rodata_ro+0xf5/0x100
[<ffffffff817415a0>] ? rest_init+0x80/0x80
[<ffffffff817415bd>] kernel_init+0x1d/0xe0
[<ffffffff8174cd1f>] ret_from_fork+0x3f/0x70
[<ffffffff817415a0>] ? rest_init+0x80/0x80
---[ end trace a1f23a1e42a2ac76 ]---
x86/mm: Checked W+X mappings: FAILED, 171 W+X pages found.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1444064120-11450-1-git-send-email-sds@tycho.nsa.gov
[ Improved the Kconfig help text and made the new option default-y
if CONFIG_DEBUG_RODATA=y, because it already found buggy mappings,
so we really want people to have this on by default. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Unused space between the end of __ex_table and the start of
rodata can be left W+x in the kernel page tables. Extend the
setting of the NX bit to cover this gap by starting from
text_end rather than rodata_start.
Before:
---[ High Kernel Mapping ]---
0xffffffff80000000-0xffffffff81000000 16M pmd
0xffffffff81000000-0xffffffff81600000 6M ro PSE GLB x pmd
0xffffffff81600000-0xffffffff81754000 1360K ro GLB x pte
0xffffffff81754000-0xffffffff81800000 688K RW GLB x pte
0xffffffff81800000-0xffffffff81a00000 2M ro PSE GLB NX pmd
0xffffffff81a00000-0xffffffff81b3b000 1260K ro GLB NX pte
0xffffffff81b3b000-0xffffffff82000000 4884K RW GLB NX pte
0xffffffff82000000-0xffffffff82200000 2M RW PSE GLB NX pmd
0xffffffff82200000-0xffffffffa0000000 478M pmd
After:
---[ High Kernel Mapping ]---
0xffffffff80000000-0xffffffff81000000 16M pmd
0xffffffff81000000-0xffffffff81600000 6M ro PSE GLB x pmd
0xffffffff81600000-0xffffffff81754000 1360K ro GLB x pte
0xffffffff81754000-0xffffffff81800000 688K RW GLB NX pte
0xffffffff81800000-0xffffffff81a00000 2M ro PSE GLB NX pmd
0xffffffff81a00000-0xffffffff81b3b000 1260K ro GLB NX pte
0xffffffff81b3b000-0xffffffff82000000 4884K RW GLB NX pte
0xffffffff82000000-0xffffffff82200000 2M RW PSE GLB NX pmd
0xffffffff82200000-0xffffffffa0000000 478M pmd
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1443704662-3138-1-git-send-email-sds@tycho.nsa.gov
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 fixes from Ingo Molnar:
- misc fixes all around the map
- block non-root vm86(old) if mmap_min_addr != 0
- two small debuggability improvements
- removal of obsolete paravirt op
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/platform: Fix Geode LX timekeeping in the generic x86 build
x86/apic: Serialize LVTT and TSC_DEADLINE writes
x86/ioapic: Force affinity setting in setup_ioapic_dest()
x86/paravirt: Remove the unused pv_time_ops::get_tsc_khz method
x86/ldt: Fix small LDT allocation for Xen
x86/vm86: Fix the misleading CONFIG_VM86 Kconfig help text
x86/cpu: Print family/model/stepping in hex
x86/vm86: Block non-root vm86(old) if mmap_min_addr != 0
x86/alternatives: Make optimize_nops() interrupt safe and synced
x86/mm/srat: Print non-volatile flag in SRAT
x86/cpufeatures: Enable cpuid for Intel SHA extensions
There are two concepts that have some confusing naming:
1. Extended State Component numbers (currently called
XFEATURE_BIT_*)
2. Extended State Component masks (currently called XSTATE_*)
The numbers are (currently) from 0-9. State component 3 is the
bounds registers for MPX, for instance.
But when we want to enable "state component 3", we go set a bit
in XCR0. The bit we set is 1<<3. We can check to see if a
state component feature is enabled by looking at its bit.
The current 'xfeature_bit's are at best xfeature bit _numbers_.
Calling them bits is at best inconsistent with ending the enum
list with 'XFEATURES_NR_MAX'.
This patch renames the enum to be 'xfeature'. These also
happen to be what the Intel documentation calls a "state
component".
We also want to differentiate these from the "XSTATE_*" macros.
The "XSTATE_*" macros are a mask, and we rename them to match.
These macros are reasonably widely used so this patch is a
wee bit big, but this really is just a rename.
The only non-mechanical part of this is the
s/XSTATE_EXTEND_MASK/XFEATURE_MASK_EXTEND/
We need a better name for it, but that's another patch.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: dave@sr71.net
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20150902233126.38653250@viggo.jf.intel.com
[ Ported to v4.3-rc1. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add the additional "vm_flags_t vm_flags" argument to do_mmap_pgoff(),
rename it to do_mmap(), and re-introduce do_mmap_pgoff() as a simple
wrapper on top of do_mmap(). Perhaps we should update the callers of
do_mmap_pgoff() and kill it later.
This way mpx_mmap() can simply call do_mmap(vm_flags => VM_MPX) and do not
play with vm internals.
After this change mmap_region() has a single user outside of mmap.c,
arch/tile/mm/elf.c:arch_setup_additional_pages(). It would be nice to
change arch/tile/ and unexport mmap_region().
[kirill@shutemov.name: fix build]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge second patch-bomb from Andrew Morton:
"Almost all of the rest of MM. There was an unusually large amount of
MM material this time"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (141 commits)
zpool: remove no-op module init/exit
mm: zbud: constify the zbud_ops
mm: zpool: constify the zpool_ops
mm: swap: zswap: maybe_preload & refactoring
zram: unify error reporting
zsmalloc: remove null check from destroy_handle_cache()
zsmalloc: do not take class lock in zs_shrinker_count()
zsmalloc: use class->pages_per_zspage
zsmalloc: consider ZS_ALMOST_FULL as migrate source
zsmalloc: partial page ordering within a fullness_list
zsmalloc: use shrinker to trigger auto-compaction
zsmalloc: account the number of compacted pages
zsmalloc/zram: introduce zs_pool_stats api
zsmalloc: cosmetic compaction code adjustments
zsmalloc: introduce zs_can_compact() function
zsmalloc: always keep per-class stats
zsmalloc: drop unused variable `nr_to_migrate'
mm/memblock.c: fix comment in __next_mem_range()
mm/page_alloc.c: fix type information of memoryless node
memory-hotplug: fix comments in zone_spanned_pages_in_node() and zone_spanned_pages_in_node()
...
When parsing SRAT, all memory ranges are added into numa_meminfo. In
numa_init(), before entering numa_cleanup_meminfo(), all possible memory
ranges are in numa_meminfo. And numa_cleanup_meminfo() removes all
ranges over max_pfn or empty.
But, this only works if the nodes are continuous. Let's have a look at
the following example:
We have an SRAT like this:
SRAT: Node 0 PXM 0 [mem 0x00000000-0x5fffffff]
SRAT: Node 0 PXM 0 [mem 0x100000000-0x1ffffffffff]
SRAT: Node 1 PXM 1 [mem 0x20000000000-0x3ffffffffff]
SRAT: Node 4 PXM 2 [mem 0x40000000000-0x5ffffffffff] hotplug
SRAT: Node 5 PXM 3 [mem 0x60000000000-0x7ffffffffff] hotplug
SRAT: Node 2 PXM 4 [mem 0x80000000000-0x9ffffffffff] hotplug
SRAT: Node 3 PXM 5 [mem 0xa0000000000-0xbffffffffff] hotplug
SRAT: Node 6 PXM 6 [mem 0xc0000000000-0xdffffffffff] hotplug
SRAT: Node 7 PXM 7 [mem 0xe0000000000-0xfffffffffff] hotplug
On boot, only node 0,1,2,3 exist.
And the numa_meminfo will look like this:
numa_meminfo.nr_blks = 9
1. on node 0: [0, 60000000]
2. on node 0: [100000000, 20000000000]
3. on node 1: [20000000000, 40000000000]
4. on node 4: [40000000000, 60000000000]
5. on node 5: [60000000000, 80000000000]
6. on node 2: [80000000000, a0000000000]
7. on node 3: [a0000000000, a0800000000]
8. on node 6: [c0000000000, a0800000000]
9. on node 7: [e0000000000, a0800000000]
And numa_cleanup_meminfo() will merge 1 and 2, and remove 8,9 because the
end address is over max_pfn, which is a0800000000. But 4 and 5 are not
removed because their end addresses are less then max_pfn. But in fact,
node 4 and 5 don't exist.
In a word, numa_cleanup_meminfo() is not able to handle holes between nodes.
Since memory ranges in node 4 and 5 are in numa_meminfo, in
numa_register_memblks(), node 4 and 5 will be mistakenly set to online.
If you run lscpu, it will show:
NUMA node0 CPU(s): 0-14,128-142
NUMA node1 CPU(s): 15-29,143-157
NUMA node2 CPU(s):
NUMA node3 CPU(s):
NUMA node4 CPU(s): 62-76,190-204
NUMA node5 CPU(s): 78-92,206-220
In this patch, we use memblock_overlaps_region() to check if ranges in
numa_meminfo overlap with ranges in memory_block. Since memory_block
contains all available memory at boot time, if they overlap, it means the
ranges exist. If not, then remove them from numa_meminfo.
After this patch, lscpu will show:
NUMA node0 CPU(s): 0-14,128-142
NUMA node1 CPU(s): 15-29,143-157
NUMA node4 CPU(s): 62-76,190-204
NUMA node5 CPU(s): 78-92,206-220
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tejun Heo <tj@kernel.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Vladimir Murzin <vladimir.murzin@arm.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull libnvdimm updates from Dan Williams:
"This update has successfully completed a 0day-kbuild run and has
appeared in a linux-next release. The changes outside of the typical
drivers/nvdimm/ and drivers/acpi/nfit.[ch] paths are related to the
removal of IORESOURCE_CACHEABLE, the introduction of memremap(), and
the introduction of ZONE_DEVICE + devm_memremap_pages().
Summary:
- Introduce ZONE_DEVICE and devm_memremap_pages() as a generic
mechanism for adding device-driver-discovered memory regions to the
kernel's direct map.
This facility is used by the pmem driver to enable pfn_to_page()
operations on the page frames returned by DAX ('direct_access' in
'struct block_device_operations').
For now, the 'memmap' allocation for these "device" pages comes
from "System RAM". Support for allocating the memmap from device
memory will arrive in a later kernel.
- Introduce memremap() to replace usages of ioremap_cache() and
ioremap_wt(). memremap() drops the __iomem annotation for these
mappings to memory that do not have i/o side effects. The
replacement of ioremap_cache() with memremap() is limited to the
pmem driver to ease merging the api change in v4.3.
Completion of the conversion is targeted for v4.4.
- Similar to the usage of memcpy_to_pmem() + wmb_pmem() in the pmem
driver, update the VFS DAX implementation and PMEM api to provide
persistence guarantees for kernel operations on a DAX mapping.
- Convert the ACPI NFIT 'BLK' driver to map the block apertures as
cacheable to improve performance.
- Miscellaneous updates and fixes to libnvdimm including support for
issuing "address range scrub" commands, clarifying the optimal
'sector size' of pmem devices, a clarification of the usage of the
ACPI '_STA' (status) property for DIMM devices, and other minor
fixes"
* tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (34 commits)
libnvdimm, pmem: direct map legacy pmem by default
libnvdimm, pmem: 'struct page' for pmem
libnvdimm, pfn: 'struct page' provider infrastructure
x86, pmem: clarify that ARCH_HAS_PMEM_API implies PMEM mapped WB
add devm_memremap_pages
mm: ZONE_DEVICE for "device memory"
mm: move __phys_to_pfn and __pfn_to_phys to asm/generic/memory_model.h
dax: drop size parameter to ->direct_access()
nd_blk: change aperture mapping from WC to WB
nvdimm: change to use generic kvfree()
pmem, dax: have direct_access use __pmem annotation
dax: update I/O path to do proper PMEM flushing
pmem: add copy_from_iter_pmem() and clear_pmem()
pmem, x86: clean up conditional pmem includes
pmem: remove layer when calling arch_has_wmb_pmem()
pmem, x86: move x86 PMEM API to new pmem.h header
libnvdimm, e820: make CONFIG_X86_PMEM_LEGACY a tristate option
pmem: switch to devm_ allocations
devres: add devm_memremap
libnvdimm, btt: write and validate parent_uuid
...
When unmapping pages it is necessary to flush the TLB. If that page was
accessed by another CPU then an IPI is used to flush the remote CPU. That
is a lot of IPIs if kswapd is scanning and unmapping >100K pages per
second.
There already is a window between when a page is unmapped and when it is
TLB flushed. This series increases the window so multiple pages can be
flushed using a single IPI. This should be safe or the kernel is hosed
already.
Patch 1 simply made the rest of the series easier to write as ftrace
could identify all the senders of TLB flush IPIS.
Patch 2 tracks what CPUs potentially map a PFN and then sends an IPI
to flush the entire TLB.
Patch 3 tracks when there potentially are writable TLB entries that
need to be batched differently
Patch 4 increases SWAP_CLUSTER_MAX to further batch flushes
The performance impact is documented in the changelogs but in the optimistic
case on a 4-socket machine the full series reduces interrupts from 900K
interrupts/second to 60K interrupts/second.
This patch (of 4):
It is easy to trace when an IPI is received to flush a TLB but harder to
detect what event sent it. This patch makes it easy to identify the
source of IPIs being transmitted for TLB flushes on x86.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With the addition of NVDIMM support, a question came up as to
whether NVDIMM ranges should be in the SRAT with this bit set.
I think the consensus was no because the ranges are in the NFIT
with proximity domain information there.
ACPI is not clear on the meaning of this bit in the SRAT.
If someone is setting it, we might want to ask them what they
expect to happen with it.
Right now this bit is only printed if all the ACPI debug
information is turned on.
Signed-off-by: Linda Knippers <linda.knippers@hp.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150901194154.GA4939@ljkz400
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 mm updates from Ingo Molnar:
"The dominant change in this cycle was the continued work to isolate
kernel drivers from MTRR legacies: this tree gets rid of all kernel
internal driver interfaces to MTRRs (mostly by rewriting it to proper
PAT interfaces), the only access left is the /proc/mtrr ABI.
This work was done by Luis R Rodriguez.
There's also some related PCI interface additions for which I've
Cc:-ed Bjorn"
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
x86/mm/mtrr: Remove kernel internal MTRR interfaces: unexport mtrr_add() and mtrr_del()
s390/io: Add pci_iomap_wc() and pci_iomap_wc_range()
drivers/dma/iop-adma: Use dma_alloc_writecombine() kernel-style
drivers/video/fbdev/vt8623fb: Use arch_phys_wc_add() and pci_iomap_wc()
drivers/video/fbdev/s3fb: Use arch_phys_wc_add() and pci_iomap_wc()
drivers/video/fbdev/arkfb.c: Use arch_phys_wc_add() and pci_iomap_wc()
PCI: Add pci_iomap_wc() variants
drivers/video/fbdev/gxt4500: Use pci_ioremap_wc_bar() to map framebuffer
drivers/video/fbdev/kyrofb: Use arch_phys_wc_add() and pci_ioremap_wc_bar()
drivers/video/fbdev/i740fb: Use arch_phys_wc_add() and pci_ioremap_wc_bar()
PCI: Add pci_ioremap_wc_bar()
x86/mm: Make kernel/check.c explicitly non-modular
x86/mm/pat: Make mm/pageattr[-test].c explicitly non-modular
x86/mm/pat: Add comments to cachemode translation tables
arch/*/io.h: Add ioremap_uc() to all architectures
drivers/video/fbdev/atyfb: Use arch_phys_wc_add() and ioremap_wc()
drivers/video/fbdev/atyfb: Replace MTRR UC hole with strong UC
drivers/video/fbdev/atyfb: Clarify ioremap() base and length used
drivers/video/fbdev/atyfb: Carve out framebuffer length fudging into a helper
x86/mm, asm-generic: Add IOMMU ioremap_uc() variant default
...
Pull x86 asm changes from Ingo Molnar:
"The biggest changes in this cycle were:
- Revamp, simplify (and in some cases fix) Time Stamp Counter (TSC)
primitives. (Andy Lutomirski)
- Add new, comprehensible entry and exit handlers written in C.
(Andy Lutomirski)
- vm86 mode cleanups and fixes. (Brian Gerst)
- 32-bit compat code cleanups. (Brian Gerst)
The amount of simplification in low level assembly code is already
palpable:
arch/x86/entry/entry_32.S | 130 +----
arch/x86/entry/entry_64.S | 197 ++-----
but more simplifications are planned.
There's also the usual laudry mix of low level changes - see the
changelog for details"
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (83 commits)
x86/asm: Drop repeated macro of X86_EFLAGS_AC definition
x86/asm/msr: Make wrmsrl() a function
x86/asm/delay: Introduce an MWAITX-based delay with a configurable timer
x86/asm: Add MONITORX/MWAITX instruction support
x86/traps: Weaken context tracking entry assertions
x86/asm/tsc: Add rdtscll() merge helper
selftests/x86: Add syscall_nt selftest
selftests/x86: Disable sigreturn_64
x86/vdso: Emit a GNU hash
x86/entry: Remove do_notify_resume(), syscall_trace_leave(), and their TIF masks
x86/entry/32: Migrate to C exit path
x86/entry/32: Remove 32-bit syscall audit optimizations
x86/vm86: Rename vm86->v86flags and v86mask
x86/vm86: Rename vm86->vm86_info to user_vm86
x86/vm86: Clean up vm86.h includes
x86/vm86: Move the vm86 IRQ definitions to vm86.h
x86/vm86: Use the normal pt_regs area for vm86
x86/vm86: Eliminate 'struct kernel_vm86_struct'
x86/vm86: Move fields from 'struct kernel_vm86_struct' to 'struct vm86'
x86/vm86: Move vm86 fields out of 'thread_struct'
...
While pmem is usable as a block device or via DAX mappings to userspace
there are several usage scenarios that can not target pmem due to its
lack of struct page coverage. In preparation for "hot plugging" pmem
into the vmemmap add ZONE_DEVICE as a new zone to tag these pages
separately from the ones that are subject to standard page allocations.
Importantly "device memory" can be removed at will by userspace
unbinding the driver of the device.
Having a separate zone prevents allocation and otherwise marks these
pages that are distinct from typical uniform memory. Device memory has
different lifetime and performance characteristics than RAM. However,
since we have run out of ZONES_SHIFT bits this functionality currently
depends on sacrificing ZONE_DMA.
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Jerome Glisse <j.glisse@gmail.com>
[hch: various simplifications in the arch interface]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Toshi explains:
"No, the default values need to be set to the fallback types,
i.e. minimal supported mode. For WC and WT, UC is the fallback type.
When PAT is disabled, pat_init() does update the tables below to
enable WT per the default BIOS setup. However, when PAT is enabled,
but CPU has PAT -errata, WT falls back to UC per the default values."
Revert: ca1fec58bc 'x86/mm/pat: Adjust default caching mode translation tables'
Requested-by: Toshi Kani <toshi.kani@hp.com>
Cc: Jan Beulich <jbeulich@suse.de>
Link: http://lkml.kernel.org/r/1437577776.3214.252.camel@hp.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
__ioremap_caller() calls region_is_ram() to walk through the
iomem_resource table to check if a target range is in RAM, which was
added to improve the lookup performance over page_is_ram() (commit
906e36c5c7 "x86: use optimized ioresource lookup in ioremap
function"). page_is_ram() was no longer used when this change was
added, though.
__ioremap_caller() then calls walk_system_ram_range(), which had
replaced page_is_ram() to improve the lookup performance (commit
c81c8a1eee "x86, ioremap: Speed up check for RAM pages").
Since both checks walk through the same iomem_resource table for
the same purpose, there is no need to call both functions.
Aside of that walk_system_ram_range() is the only useful check at the
moment because region_is_ram() always returns -1 due to an
implementation bug. That bug in region_is_ram() cannot be fixed
without breaking existing ioremap callers, which rely on the subtle
difference of walk_system_ram_range() versus non page aligned ranges.
Once these offending callers are fixed we can use region_is_ram() and
remove walk_system_ram_range().
[ tglx: Massaged changelog ]
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Mike Travis <travis@sgi.com>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/1437088996-28511-3-git-send-email-toshi.kani@hp.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
__ioremap_check_ram() has a WARN_ONCE() which is emitted when the
given pfn range is not RAM. The warning is bogus in two aspects:
- it never triggers since walk_system_ram_range() only calls
__ioremap_check_ram() for RAM ranges.
- the warning message is wrong as it says: "ioremap on RAM' after it
established that the pfn range is not RAM.
Move the WARN_ONCE() to __ioremap_caller(), and update the message to
include the address range so we get an actual warning when something
tries to ioremap system RAM.
[ tglx: Massaged changelog ]
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/1437088996-28511-2-git-send-email-toshi.kani@hp.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
MPX setups private anonymous mapping, but uses vma->vm_ops too.
This can confuse core VM, as it relies on vm->vm_ops to
distinguish file VMAs from anonymous.
As result we will get SIGBUS, because handle_pte_fault() thinks
it's file VMA without vm_ops->fault and it doesn't know how to
handle the situation properly.
Let's fix that by not setting ->vm_ops.
We don't really need ->vm_ops here: MPX VMA can be detected with
VM_MPX flag. And vma_merge() will not merge MPX VMA with non-MPX
VMA, because ->vm_flags won't match.
The only thing left is name of VMA. I'm not sure if it's part of
ABI, or we can just drop it. The patch keep it by providing
arch_vma_name() on x86.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@vger.kernel.org> # Fixes: 6b7339f4 (mm: avoid setting up anonymous pages into file mapping)
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dave@sr71.net
Link: http://lkml.kernel.org/r/20150720212958.305CC3E9@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Some high end Intel Xeon systems report uncorrectable memory errors as a
recoverable machine check. Linux has included code for some time to
process these and just signal the affected processes (or even recover
completely if the error was in a read only page that can be replaced by
reading from disk).
But we have no recovery path for errors encountered during kernel code
execution. Except for some very specific cases were are unlikely to ever
be able to recover.
Enter memory mirroring. Actually 3rd generation of memory mirroing.
Gen1: All memory is mirrored
Pro: No s/w enabling - h/w just gets good data from other side of the
mirror
Con: Halves effective memory capacity available to OS/applications
Gen2: Partial memory mirror - just mirror memory begind some memory controllers
Pro: Keep more of the capacity
Con: Nightmare to enable. Have to choose between allocating from
mirrored memory for safety vs. NUMA local memory for performance
Gen3: Address range partial memory mirror - some mirror on each memory
controller
Pro: Can tune the amount of mirror and keep NUMA performance
Con: I have to write memory management code to implement
The current plan is just to use mirrored memory for kernel allocations.
This has been broken into two phases:
1) This patch series - find the mirrored memory, use it for boot time
allocations
2) Wade into mm/page_alloc.c and define a ZONE_MIRROR to pick up the
unused mirrored memory from mm/memblock.c and only give it out to
select kernel allocations (this is still being scoped because
page_alloc.c is scary).
This patch (of 3):
Add extra "flags" to memblock to allow selection of memory based on
attribute. No functional changes
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Xiexiuqi <xiexiuqi@huawei.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull x86 core updates from Ingo Molnar:
"There were so many changes in the x86/asm, x86/apic and x86/mm topics
in this cycle that the topical separation of -tip broke down somewhat -
so the result is a more traditional architecture pull request,
collected into the 'x86/core' topic.
The topics were still maintained separately as far as possible, so
bisectability and conceptual separation should still be pretty good -
but there were a handful of merge points to avoid excessive
dependencies (and conflicts) that would have been poorly tested in the
end.
The next cycle will hopefully be much more quiet (or at least will
have fewer dependencies).
The main changes in this cycle were:
* x86/apic changes, with related IRQ core changes: (Jiang Liu, Thomas
Gleixner)
- This is the second and most intrusive part of changes to the x86
interrupt handling - full conversion to hierarchical interrupt
domains:
[IOAPIC domain] -----
|
[MSI domain] --------[Remapping domain] ----- [ Vector domain ]
| (optional) |
[HPET MSI domain] ----- |
|
[DMAR domain] -----------------------------
|
[Legacy domain] -----------------------------
This now reflects the actual hardware and allowed us to distangle
the domain specific code from the underlying parent domain, which
can be optional in the case of interrupt remapping. It's a clear
separation of functionality and removes quite some duct tape
constructs which plugged the remap code between ioapic/msi/hpet
and the vector management.
- Intel IOMMU IRQ remapping enhancements, to allow direct interrupt
injection into guests (Feng Wu)
* x86/asm changes:
- Tons of cleanups and small speedups, micro-optimizations. This
is in preparation to move a good chunk of the low level entry
code from assembly to C code (Denys Vlasenko, Andy Lutomirski,
Brian Gerst)
- Moved all system entry related code to a new home under
arch/x86/entry/ (Ingo Molnar)
- Removal of the fragile and ugly CFI dwarf debuginfo annotations.
Conversion to C will reintroduce many of them - but meanwhile
they are only getting in the way, and the upstream kernel does
not rely on them (Ingo Molnar)
- NOP handling refinements. (Borislav Petkov)
* x86/mm changes:
- Big PAT and MTRR rework: making the code more robust and
preparing to phase out exposing direct MTRR interfaces to drivers -
in favor of using PAT driven interfaces (Toshi Kani, Luis R
Rodriguez, Borislav Petkov)
- New ioremap_wt()/set_memory_wt() interfaces to support
Write-Through cached memory mappings. This is especially
important for good performance on NVDIMM hardware (Toshi Kani)
* x86/ras changes:
- Add support for deferred errors on AMD (Aravind Gopalakrishnan)
This is an important RAS feature which adds hardware support for
poisoned data. That means roughly that the hardware marks data
which it has detected as corrupted but wasn't able to correct, as
poisoned data and raises an APIC interrupt to signal that in the
form of a deferred error. It is the OS's responsibility then to
take proper recovery action and thus prolonge system lifetime as
far as possible.
- Add support for Intel "Local MCE"s: upcoming CPUs will support
CPU-local MCE interrupts, as opposed to the traditional system-
wide broadcasted MCE interrupts (Ashok Raj)
- Misc cleanups (Borislav Petkov)
* x86/platform changes:
- Intel Atom SoC updates
... and lots of other cleanups, fixlets and other changes - see the
shortlog and the Git log for details"
* 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (222 commits)
x86/hpet: Use proper hpet device number for MSI allocation
x86/hpet: Check for irq==0 when allocating hpet MSI interrupts
x86/mm/pat, drivers/infiniband/ipath: Use arch_phys_wc_add() and require PAT disabled
x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled
x86/platform/intel/baytrail: Add comments about why we disabled HPET on Baytrail
genirq: Prevent crash in irq_move_irq()
genirq: Enhance irq_data_to_desc() to support hierarchy irqdomain
iommu, x86: Properly handle posted interrupts for IOMMU hotplug
iommu, x86: Provide irq_remapping_cap() interface
iommu, x86: Setup Posted-Interrupts capability for Intel iommu
iommu, x86: Add cap_pi_support() to detect VT-d PI capability
iommu, x86: Avoid migrating VT-d posted interrupts
iommu, x86: Save the mode (posted or remapped) of an IRTE
iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip
iommu: dmar: Provide helper to copy shared irte fields
iommu: dmar: Extend struct irte for VT-d Posted-Interrupts
iommu: Add new member capability to struct irq_remap_ops
x86/asm/entry/64: Disentangle error_entry/exit gsbase/ebx/usermode code
x86/asm/entry/32: Shorten __audit_syscall_entry() args preparation
x86/asm/entry/32: Explain reloading of registers after __audit_syscall_entry()
...
Pull x86 FPU updates from Ingo Molnar:
"This tree contains two main changes:
- The big FPU code rewrite: wide reaching cleanups and reorganization
that pulls all the FPU code together into a clean base in
arch/x86/fpu/.
The resulting code is leaner and faster, and much easier to
understand. This enables future work to further simplify the FPU
code (such as removing lazy FPU restores).
By its nature these changes have a substantial regression risk: FPU
code related bugs are long lived, because races are often subtle
and bugs mask as user-space failures that are difficult to track
back to kernel side backs. I'm aware of no unfixed (or even
suspected) FPU related regression so far.
- MPX support rework/fixes. As this is still not a released CPU
feature, there were some buglets in the code - should be much more
robust now (Dave Hansen)"
* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (250 commits)
x86/fpu: Fix double-increment in setup_xstate_features()
x86/mpx: Allow 32-bit binaries on 64-bit kernels again
x86/mpx: Do not count MPX VMAs as neighbors when unmapping
x86/mpx: Rewrite the unmap code
x86/mpx: Support 32-bit binaries on 64-bit kernels
x86/mpx: Use 32-bit-only cmpxchg() for 32-bit apps
x86/mpx: Introduce new 'directory entry' to 'addr' helper function
x86/mpx: Add temporary variable to reduce masking
x86: Make is_64bit_mm() widely available
x86/mpx: Trace allocation of new bounds tables
x86/mpx: Trace the attempts to find bounds tables
x86/mpx: Trace entry to bounds exception paths
x86/mpx: Trace #BR exceptions
x86/mpx: Introduce a boot-time disable flag
x86/mpx: Restrict the mmap() size check to bounds tables
x86/mpx: Remove redundant MPX_BNDCFG_ADDR_MASK
x86/mpx: Clean up the code by not passing a task pointer around when unnecessary
x86/mpx: Use the new get_xsave_field_ptr()API
x86/fpu/xstate: Wrap get_xsave_addr() to make it safer
x86/fpu/xstate: Fix up bad get_xsave_addr() assumptions
...
Pull x86 cleanups from Ingo Molnar:
"Misc cleanups"
* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Clean up types in xlate_dev_mem_ptr() some more
x86: Deinline dma_free_attrs()
x86: Deinline dma_alloc_attrs()
x86: Remove unused TI_cpu
x86: Merge common 32-bit values in asm-offsets.c
The comment pretty much says it all.
I wrote a test program that does lots of random allocations
and forces bounds tables to be created. It came up with a
layout like this:
.... | BOUNDS DIRECTORY ENTRY COVERS | ....
| BOUNDS TABLE COVERS |
| BOUNDS TABLE | REAL ALLOC | BOUNDS TABLE |
Unmapping "REAL ALLOC" should have been able to free the
bounds table "covering" the "REAL ALLOC" because it was the
last real user. But, the neighboring VMA bounds tables were
found, considered as real neighbors, and we declined to free
the bounds table covering the area.
Doing this over and over left a small but significant number
of these orphans. Handling them is fairly straighforward.
All we have to do is walk the VMAs and skip all of the MPX
ones when looking for neighbors.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150607183706.A6BD90BF@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The MPX code needs to clear out bounds tables for memory which
is no longer in use. We do this when a userspace mapping is
torn down (unmapped).
There are two modes:
1. An entire bounds table becomes unused, and can be freed
and its pointer removed from the bounds directory. This
happens either when a large mapping is torn down, or when
a small mapping is torn down and it is the last mapping
"covered" by a bounds table.
2. Only part of a bounds table becomes unused, in which case
we free the backing memory as if MADV_DONTNEED was called.
The old code was a spaghetti mess of "edge" bounds tables
where the edges were handled specially, even if we were
unmapping an entire one. Non-edge bounds tables are always
fully unmapped, but share a different code path from the edge
ones. The old code had a bug where it was unmapping too much
memory. I worked on fixing it for two days and gave up.
I didn't write the original code. I didn't particularly like
it, but it worked, so I left it. After my debug session, I
realized it was undebuggagle *and* buggy, so out it went.
I also wrote a new unmapping test program which uncovers bugs
pretty nicely.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150607183706.DCAEC67D@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Right now, the kernel can only switch between 64-bit and 32-bit
binaries at compile time. This patch adds support for 32-bit
binaries on 64-bit kernels when we support ia32 emulation.
We essentially choose which set of table sizes to use when doing
arithmetic for the bounds table calculations.
This also uses a different approach for calculating the table
indexes than before. I think the new one makes it much more
clear what is going on, and allows us to share more code between
the 32-bit and 64-bit cases.
Based-on-patch-by: Qiaowei Ren <qiaowei.ren@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150607183705.E01F21E2@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
user_atomic_cmpxchg_inatomic() actually looks at sizeof(*ptr) to
figure out how many bytes to copy. If we run it on a 64-bit
kernel with a 64-bit pointer, it will copy a 64-bit bounds
directory entry. That's fine, except when we have 32-bit
programs with 32-bit bounds directory entries and we only *want*
32-bits.
This patch breaks the cmpxchg() operation out in to its own
function and performs the 32-bit type swizzling in there.
Note, the "64-bit" version of this code _would_ work on a
32-bit-only kernel. The issue this patch addresses is only for
when the kernel's 'long' is mismatched from the size of the
bounds directory entry of the process we are working on.
The new helper modifies 'actual_old_val' or returns an error.
But gcc doesn't know this, so it warns about 'actual_old_val'
being unused. Shut it up with an uninitialized_var().
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150607183705.672B115E@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
