There's a conflict between ongoing level-5 paging support and
the E820 rewrite. Since the E820 rewrite is essentially ready,
merge it into x86/mm to reduce tree conflicts.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
... to have a natural "likely()" in the code flow and thus have the
success case with a branch 99.999% of the times non-taken and function
return code following it instead of jumping to it each time.
This puts the panic() call at the end of the function - it is going to
be practically unreachable anyway.
The C code is a bit more readable too.
No functionality change.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
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: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: thgarnie@google.com
Link: http://lkml.kernel.org/r/20170330080101.ywsf5rg6ilzu4itk@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This code seems to be very old and has gotten only minor updates.
It's overcomplicated and has a bunch of comments that are, at best,
of purely historical interest. Nowadays we have a shiny function
probe_kernel_write() that does more or less exactly what we need.
Use it.
I switched the page that we test from swapper_pg_dir to
empty_zero_page because writing zero to empty_zero_page is more
obviously safe than writing to the paging structures. (It's
extremely unlikely that any of this would cause problems in practice
because the write will fail on any supported CPU.)
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/0b9e64ab0236de30e7572213cea77bf95ae2e990.1490831211.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch only covers simple cases. Less trivial cases will be
converted with separate patches.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170313143309.16020-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Remove the wp_works_ok member of struct cpuinfo_x86. It's an
optimization back from Linux v0.99 times where we had no fixup support
yet and did the CR0.WP test via special code in the page fault handler.
The < 0 test was an optimization to not do the special casing for each
NULL ptr access violation but just for the first one doing the WP test.
Today it serves no real purpose as the test no longer needs special code
in the page fault handler and the only call side -- mem_init() -- calls
it just once, anyway. However, Xen pre-initializes it to 1, to skip the
test.
Doing the test again for Xen should be no issue at all, as even the
commit introducing skipping the test (commit d560bc6157 ("x86, xen:
Suppress WP test on Xen")) mentioned it being ban aid only. And, in
fact, testing the patch on Xen showed nothing breaks.
The pre-fixup times are long gone and with the removal of the fallback
handling code in commit a5c2a893db ("x86, 386 removal: Remove
CONFIG_X86_WP_WORKS_OK") the kernel requires a working CR0.WP anyway.
So just get rid of the "optimization" and do the test unconditionally.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Arnd Hannemann <hannemann@nets.rwth-aachen.de>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "David S. Miller" <davem@davemloft.net>
Link: http://lkml.kernel.org/r/1486933932-585-3-git-send-email-minipli@googlemail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch makes arch-independent testcases for RODATA. Both x86 and
x86_64 already have testcases for RODATA, But they are arch-specific
because using inline assembly directly.
And cacheflush.h is not a suitable location for rodata-test related
things. Since they were in cacheflush.h, If someone change the state of
CONFIG_DEBUG_RODATA_TEST, It cause overhead of kernel build.
To solve the above issues, write arch-independent testcases and move it
to shared location.
[jinb.park7@gmail.com: fix config dependency]
Link: http://lkml.kernel.org/r/20170209131625.GA16954@pjb1027-Latitude-E5410
Link: http://lkml.kernel.org/r/20170129105436.GA9303@pjb1027-Latitude-E5410
Signed-off-by: Jinbum Park <jinb.park7@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In line with asm/e820/types.h, move the e820 API declarations to
asm/e820/api.h and update all usage sites.
This is just a mechanical, obviously correct move & replace patch,
there will be subsequent changes to clean up the code and to make
better use of the new header organization.
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends. That changed
when we forked out support for the latter into the export.h file.
This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig. The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.
Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
for the presence of either and replace accordingly where needed.
Note that some bool/obj-y instances remain since module.h is
the header for some exception table entry stuff, and for things
like __init_or_module (code that is tossed when MODULES=n).
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160714001901.31603-3-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 boot updates from Ingo Molnar:
"The biggest changes in this cycle were:
- prepare for more KASLR related changes, by restructuring, cleaning
up and fixing the existing boot code. (Kees Cook, Baoquan He,
Yinghai Lu)
- simplifly/concentrate subarch handling code, eliminate
paravirt_enabled() usage. (Luis R Rodriguez)"
* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits)
x86/KASLR: Clarify purpose of each get_random_long()
x86/KASLR: Add virtual address choosing function
x86/KASLR: Return earliest overlap when avoiding regions
x86/KASLR: Add 'struct slot_area' to manage random_addr slots
x86/boot: Add missing file header comments
x86/KASLR: Initialize mapping_info every time
x86/boot: Comment what finalize_identity_maps() does
x86/KASLR: Build identity mappings on demand
x86/boot: Split out kernel_ident_mapping_init()
x86/boot: Clean up indenting for asm/boot.h
x86/KASLR: Improve comments around the mem_avoid[] logic
x86/boot: Simplify pointer casting in choose_random_location()
x86/KASLR: Consolidate mem_avoid[] entries
x86/boot: Clean up pointer casting
x86/boot: Warn on future overlapping memcpy() use
x86/boot: Extract error reporting functions
x86/boot: Correctly bounds-check relocations
x86/KASLR: Clean up unused code from old 'run_size' and rename it to 'kernel_total_size'
x86/boot: Fix "run_size" calculation
x86/boot: Calculate decompression size during boot not build
...
Currently CONFIG_RANDOMIZE_BASE_MAX_OFFSET is used to limit the maximum
offset for kernel randomization. This limit doesn't need to be a CONFIG
since it is tied completely to KERNEL_IMAGE_SIZE, and will make no sense
once physical and virtual offsets are randomized separately. This patch
removes CONFIG_RANDOMIZE_BASE_MAX_OFFSET and consolidates the Kconfig
help text.
[kees: rewrote changelog, dropped KERNEL_IMAGE_SIZE_DEFAULT, rewrote help]
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: H.J. Lu <hjl.tools@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1461185746-8017-3-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 mm updates from Ingo Molnar:
"The main changes in this cycle were:
- Enable full ASLR randomization for 32-bit programs (Hector
Marco-Gisbert)
- Add initial minimal INVPCI support, to flush global mappings (Andy
Lutomirski)
- Add KASAN enhancements (Andrey Ryabinin)
- Fix mmiotrace for huge pages (Karol Herbst)
- ... misc cleanups and small enhancements"
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm/32: Enable full randomization on i386 and X86_32
x86/mm/kmmio: Fix mmiotrace for hugepages
x86/mm: Avoid premature success when changing page attributes
x86/mm/ptdump: Remove paravirt_enabled()
x86/mm: Fix INVPCID asm constraint
x86/dmi: Switch dmi_remap() from ioremap() [uncached] to ioremap_cache()
x86/mm: If INVPCID is available, use it to flush global mappings
x86/mm: Add a 'noinvpcid' boot option to turn off INVPCID
x86/mm: Add INVPCID helpers
x86/kasan: Write protect kasan zero shadow
x86/kasan: Clear kasan_zero_page after TLB flush
x86/mm/numa: Check for failures in numa_clear_kernel_node_hotplug()
x86/mm/numa: Clean up numa_clear_kernel_node_hotplug()
x86/mm: Make kmap_prot into a #define
x86/mm/32: Set NX in __supported_pte_mask before enabling paging
x86/mm: Streamline and restore probe_memory_block_size()
This removes the CONFIG_DEBUG_RODATA option and makes it always enabled.
This simplifies the code and also makes it clearer that read-only mapped
memory is just as fundamental a security feature in kernel-space as it is
in user-space.
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Brown <david.brown@linaro.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathias Krause <minipli@googlemail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-hardening@lists.openwall.com
Cc: linux-arch <linux-arch@vger.kernel.org>
Link: http://lkml.kernel.org/r/1455748879-21872-4-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The value (once we initialize it) is a foregone conclusion.
Make it a #define to save a tiny amount of text and data size
and to make it more comprehensible.
Signed-off-by: Andy Lutomirski <luto@kernel.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: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/0850eb0213de9da88544ff7fae72dc6d06d2b441.1453239349.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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>
1/ 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.
2/ 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.
3/ 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.
4/ Convert the ACPI NFIT 'BLK' driver to map the block apertures as
cacheable to improve performance.
5/ 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.
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Merge tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
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
...
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>
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>
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>
This patch introduces zone_for_memory() to arch_add_memory() on x86_32
to ensure new, higher memory added into ZONE_MOVABLE if movable zone has
already setup.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Mel Gorman" <mgorman@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On 64-bit, this raises the maximum location to -1 GiB (from -1.5 GiB),
the upper limit currently, since the kernel fixmap page mappings need
to be moved to use the other 1 GiB (which would be the theoretical
limit when building with -mcmodel=kernel).
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/1381450698-28710-7-git-send-email-keescook@chromium.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Concentrate code to modify totalram_pages into the mm core, so the arch
memory initialized code doesn't need to take care of it. With these
changes applied, only following functions from mm core modify global
variable totalram_pages: free_bootmem_late(), free_all_bootmem(),
free_all_bootmem_node(), adjust_managed_page_count().
With this patch applied, it will be much more easier for us to keep
totalram_pages and zone->managed_pages in consistence.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: David Howells <dhowells@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: <sworddragon2@aol.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Jianguo Wu <wujianguo@huawei.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Michel Lespinasse <walken@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use helper function free_highmem_page() to free highmem pages into
the buddy system.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Cong Wang <amwang@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Attilio Rao <attilio.rao@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For removing memory, we need to remove page tables. But it depends on
architecture. So the patch introduce arch_remove_memory() for removing
page table. Now it only calls __remove_pages().
Note: __remove_pages() for some archtecuture is not implemented
(I don't know how to implement it for s390).
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Jianguo Wu <wujianguo@huawei.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Wu Jianguo <wujianguo@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Coming patches to x86/mm2 require the changes and advanced baseline in
x86/boot.
Resolved Conflicts:
arch/x86/kernel/setup.c
mm/nobootmem.c
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
after_bootmem has different meaning in 32bit and 64bit.
32bit: after bootmem is ready
64bit: after bootmem is distroyed
Let's merget them make 32bit the same as 64bit.
for 32bit, it is mixing alloc_bootmem_pages, and alloc_low_page under
after_bootmem is set or not set.
alloc_bootmem is just wrapper for memblock for x86.
Now we have alloc_low_page() with memblock too. We can drop bootmem path
now, and only alloc_low_page only.
At the same time, we make alloc_low_page could handle real after_bootmem
for 32bit, because alloc_bootmem_pages could fallback to use slab too.
At last move after_bootmem set position for 32bit the same as 64bit.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1353123563-3103-40-git-send-email-yinghai@kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
During test patch that adjust page_size_mask to map small range ram with
big page size, found page table is setup wrongly for 32bit. And
native_pagetable_init wrong clear pte for pmd with large page support.
1. add more comments about why we are expecting pte.
2. add BUG checking, so next time we could find problem earlier
when we mess up page table setup again.
3. max_low_pfn is not included boundary for low memory mapping.
We should check from max_low_pfn instead of +1.
4. add print out when some pte really get cleared, or we should use
WARN() to find out why above max_low_pfn get mapped? so we could
fix it.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1353123563-3103-35-git-send-email-yinghai@kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
On 32bit, before patcheset that only set page table for ram, we only
call that one time.
Now, we are calling that during every init_memory_mapping if we have holes
under max_low_pfn.
We should only call it one time after all ranges under max_low_page get
mapped just like we did before.
Also that could avoid the risk to run out of pgt_buf in BRK.
Need to update page_table_range_init() to count the pages for kmap page table
at first, and use new added alloc_low_pages() to get pages in sequence.
That will conform to the requirement that pages need to be in low to high order.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1353123563-3103-30-git-send-email-yinghai@kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
They are almost same except 64 bit need to handle after_bootmem case.
Add mm_internal.h to make that alloc_low_page() only to be accessible
from arch/x86/mm/init*.c
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1353123563-3103-25-git-send-email-yinghai@kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Get pgt_buf early from BRK, and use it to map PMD_SIZE from top at first.
Then use mapped pages to map more ranges below, and keep looping until
all pages get mapped.
alloc_low_page will use page from BRK at first, after that buffer is used
up, will use memblock to find and reserve pages for page table usage.
Introduce min_pfn_mapped to make sure find new pages from mapped ranges,
that will be updated when lower pages get mapped.
Also add step_size to make sure that don't try to map too big range with
limited mapped pages initially, and increase the step_size when we have
more mapped pages on hand.
We don't need to call pagetable_reserve anymore, reserve work is done
in alloc_low_page() directly.
At last we can get rid of calculation and find early pgt related code.
-v2: update to after fix_xen change,
also use MACRO for initial pgt_buf size and add comments with it.
-v3: skip big reserved range in memblock.reserved near end.
-v4: don't need fix_xen change now.
-v5: add changelog about moving about reserving pagetable to alloc_low_page.
Suggested-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1353123563-3103-22-git-send-email-yinghai@kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
We are going to use buffer in BRK to map small range just under memory top,
and use those new mapped ram to map ram range under it.
The ram range that will be mapped at first could be only page aligned,
but ranges around it are ram too, we could use bigger page to map it to
avoid small page size.
We will adjust page_size_mask in following patch:
x86, mm: Use big page size for small memory range
to use big page size for small ram range.
Before that patch, this patch will make sure start address to be
aligned down according to bigger page size, otherwise entry in page
page will not have correct value.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1353123563-3103-18-git-send-email-yinghai@kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Pull x86/smap support from Ingo Molnar:
"This adds support for the SMAP (Supervisor Mode Access Prevention) CPU
feature on Intel CPUs: a hardware feature that prevents unintended
user-space data access from kernel privileged code.
It's turned on automatically when possible.
This, in combination with SMEP, makes it even harder to exploit kernel
bugs such as NULL pointer dereferences."
Fix up trivial conflict in arch/x86/kernel/entry_64.S due to newly added
includes right next to each other.
* 'x86-smap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, smep, smap: Make the switching functions one-way
x86, suspend: On wakeup always initialize cr4 and EFER
x86-32: Start out eflags and cr4 clean
x86, smap: Do not abuse the [f][x]rstor_checking() functions for user space
x86-32, smap: Add STAC/CLAC instructions to 32-bit kernel entry
x86, smap: Reduce the SMAP overhead for signal handling
x86, smap: A page fault due to SMAP is an oops
x86, smap: Turn on Supervisor Mode Access Prevention
x86, smap: Add STAC and CLAC instructions to control user space access
x86, uaccess: Merge prototypes for clear_user/__clear_user
x86, smap: Add a header file with macros for STAC/CLAC
x86, alternative: Add header guards to <asm/alternative-asm.h>
x86, alternative: Use .pushsection/.popsection
x86, smap: Add CR4 bit for SMAP
x86-32, mm: The WP test should be done on a kernel page
At this stage x86_init.paging.pagetable_setup_done is only used in the
XEN case. Move its content in the x86_init.paging.pagetable_init setup
function and remove the now unused x86_init.paging.pagetable_setup_done
remaining infrastructure.
Signed-off-by: Attilio Rao <attilio.rao@citrix.com>
Acked-by: <konrad.wilk@oracle.com>
Cc: <Ian.Campbell@citrix.com>
Cc: <Stefano.Stabellini@eu.citrix.com>
Cc: <xen-devel@lists.xensource.com>
Link: http://lkml.kernel.org/r/1345580561-8506-5-git-send-email-attilio.rao@citrix.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Move the paging_init() call to the platform specific pagetable_init()
function, so we can get rid of the extra pagetable_setup_done()
function pointer.
Signed-off-by: Attilio Rao <attilio.rao@citrix.com>
Acked-by: <konrad.wilk@oracle.com>
Cc: <Ian.Campbell@citrix.com>
Cc: <Stefano.Stabellini@eu.citrix.com>
Cc: <xen-devel@lists.xensource.com>
Link: http://lkml.kernel.org/r/1345580561-8506-4-git-send-email-attilio.rao@citrix.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In preparation for unifying the pagetable_setup_start() and
pagetable_setup_done() setup functions, rename appropriately all the
infrastructure related to pagetable_setup_start().
Signed-off-by: Attilio Rao <attilio.rao@citrix.com>
Ackedd-by: <konrad.wilk@oracle.com>
Cc: <Ian.Campbell@citrix.com>
Cc: <Stefano.Stabellini@eu.citrix.com>
Cc: <xen-devel@lists.xensource.com>
Link: http://lkml.kernel.org/r/1345580561-8506-3-git-send-email-attilio.rao@citrix.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We either use swapper_pg_dir or the argument is unused. Preparatory
patch to simplify platform pagetable setup further.
Signed-off-by: Attilio Rao <attilio.rao@citrix.com>
Ackedb-by: <konrad.wilk@oracle.com>
Cc: <Ian.Campbell@citrix.com>
Cc: <Stefano.Stabellini@eu.citrix.com>
Cc: <xen-devel@lists.xensource.com>
Link: http://lkml.kernel.org/r/1345580561-8506-2-git-send-email-attilio.rao@citrix.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/numa: Add constraints check for nid parameters
mm, x86: Remove debug_pagealloc_enabled
x86/mm: Initialize high mem before free_all_bootmem()
arch/x86/kernel/e820.c: quiet sparse noise about plain integer as NULL pointer
arch/x86/kernel/e820.c: Eliminate bubble sort from sanitize_e820_map()
x86: Fix mmap random address range
x86, mm: Unify zone_sizes_init()
x86, mm: Prepare zone_sizes_init() for unification
x86, mm: Use max_low_pfn for ZONE_NORMAL on 64-bit
x86, mm: Wrap ZONE_DMA32 with CONFIG_ZONE_DMA32
x86, mm: Use max_pfn instead of highend_pfn
x86, mm: Move zone init from paging_init() on 64-bit
x86, mm: Use MAX_DMA_PFN for ZONE_DMA on 32-bit
Patch fixes a boot crash with pagealloc debugging enabled:
Initializing HighMem for node 0 (000377fe:0003fff0)
BUG: unable to handle kernel paging request at f6fefe80
IP: [<c1621ab5>] find_range_array+0x5e/0x69
[...]
Call Trace:
[<c1622064>] __get_free_all_memory_range+0x39/0xb4
[<c1620dd0>] add_highpages_with_active_regions+0x18/0x9b
[<c1621a2e>] set_highmem_pages_init+0x70/0x90
[<c162122b>] mem_init+0x50/0x21b
[<c16155bd>] start_kernel+0x1bf/0x31c
[<c1615065>] i386_start_kernel+0x65/0x67
The crash happens when memblock wants to allocate big area for
temporary "struct range" array and reuses pages from top of low
memory, which were already passed to the buddy allocator.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: linux-mm@kvack.org
Cc: Mel Gorman <mgorman@suse.de>
Link: http://lkml.kernel.org/r/20111206080833.GB3105@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Now that zone_sizes_init() is identical on 32-bit and 64-bit,
move the code to arch/x86/mm/init.c and use it for both
architectures.
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
Link: http://lkml.kernel.org/r/1320155902-10424-7-git-send-email-penberg@kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
