arch_add_memory gets for_device argument which then controls whether we
want to create memblocks for created memory sections. Simplify the
logic by telling whether we want memblocks directly rather than going
through pointless negation. This also makes the api easier to
understand because it is clear what we want rather than nothing telling
for_device which can mean anything.
This shouldn't introduce any functional change.
Link: http://lkml.kernel.org/r/20170515085827.16474-13-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The current memory hotplug implementation relies on having all the
struct pages associate with a zone/node during the physical hotplug
phase (arch_add_memory->__add_pages->__add_section->__add_zone). In the
vast majority of cases this means that they are added to ZONE_NORMAL.
This has been so since 9d99aaa31f ("[PATCH] x86_64: Support memory
hotadd without sparsemem") and it wasn't a big deal back then because
movable onlining didn't exist yet.
Much later memory hotplug wanted to (ab)use ZONE_MOVABLE for movable
onlining 511c2aba8f ("mm, memory-hotplug: dynamic configure movable
memory and portion memory") and then things got more complicated.
Rather than reconsidering the zone association which was no longer
needed (because the memory hotplug already depended on SPARSEMEM) a
convoluted semantic of zone shifting has been developed. Only the
currently last memblock or the one adjacent to the zone_movable can be
onlined movable. This essentially means that the online type changes as
the new memblocks are added.
Let's simulate memory hot online manually
$ echo 0x100000000 > /sys/devices/system/memory/probe
$ grep . /sys/devices/system/memory/memory32/valid_zones
Normal Movable
$ echo $((0x100000000+(128<<20))) > /sys/devices/system/memory/probe
$ grep . /sys/devices/system/memory/memory3?/valid_zones
/sys/devices/system/memory/memory32/valid_zones:Normal
/sys/devices/system/memory/memory33/valid_zones:Normal Movable
$ echo $((0x100000000+2*(128<<20))) > /sys/devices/system/memory/probe
$ grep . /sys/devices/system/memory/memory3?/valid_zones
/sys/devices/system/memory/memory32/valid_zones:Normal
/sys/devices/system/memory/memory33/valid_zones:Normal
/sys/devices/system/memory/memory34/valid_zones:Normal Movable
$ echo online_movable > /sys/devices/system/memory/memory34/state
$ grep . /sys/devices/system/memory/memory3?/valid_zones
/sys/devices/system/memory/memory32/valid_zones:Normal
/sys/devices/system/memory/memory33/valid_zones:Normal Movable
/sys/devices/system/memory/memory34/valid_zones:Movable Normal
This is an awkward semantic because an udev event is sent as soon as the
block is onlined and an udev handler might want to online it based on
some policy (e.g. association with a node) but it will inherently race
with new blocks showing up.
This patch changes the physical online phase to not associate pages with
any zone at all. All the pages are just marked reserved and wait for
the onlining phase to be associated with the zone as per the online
request. There are only two requirements
- existing ZONE_NORMAL and ZONE_MOVABLE cannot overlap
- ZONE_NORMAL precedes ZONE_MOVABLE in physical addresses
the latter one is not an inherent requirement and can be changed in the
future. It preserves the current behavior and made the code slightly
simpler. This is subject to change in future.
This means that the same physical online steps as above will lead to the
following state: Normal Movable
/sys/devices/system/memory/memory32/valid_zones:Normal Movable
/sys/devices/system/memory/memory33/valid_zones:Normal Movable
/sys/devices/system/memory/memory32/valid_zones:Normal Movable
/sys/devices/system/memory/memory33/valid_zones:Normal Movable
/sys/devices/system/memory/memory34/valid_zones:Normal Movable
/sys/devices/system/memory/memory32/valid_zones:Normal Movable
/sys/devices/system/memory/memory33/valid_zones:Normal Movable
/sys/devices/system/memory/memory34/valid_zones:Movable
Implementation:
The current move_pfn_range is reimplemented to check the above
requirements (allow_online_pfn_range) and then updates the respective
zone (move_pfn_range_to_zone), the pgdat and links all the pages in the
pfn range with the zone/node. __add_pages is updated to not require the
zone and only initializes sections in the range. This allowed to
simplify the arch_add_memory code (s390 could get rid of quite some of
code).
devm_memremap_pages is the only user of arch_add_memory which relies on
the zone association because it only hooks into the memory hotplug only
half way. It uses it to associate the new memory with ZONE_DEVICE but
doesn't allow it to be {on,off}lined via sysfs. This means that this
particular code path has to call move_pfn_range_to_zone explicitly.
The original zone shifting code is kept in place and will be removed in
the follow up patch for an easier review.
Please note that this patch also changes the original behavior when
offlining a memory block adjacent to another zone (Normal vs. Movable)
used to allow to change its movable type. This will be handled later.
[richard.weiyang@gmail.com: simplify zone_intersects()]
Link: http://lkml.kernel.org/r/20170616092335.5177-1-richard.weiyang@gmail.com
[richard.weiyang@gmail.com: remove duplicate call for set_page_links]
Link: http://lkml.kernel.org/r/20170616092335.5177-2-richard.weiyang@gmail.com
[akpm@linux-foundation.org: remove unused local `i']
Link: http://lkml.kernel.org/r/20170515085827.16474-12-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # For s390 bits
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Device memory hotplug hooks into regular memory hotplug only half way.
It needs memory sections to track struct pages but there is no
need/desire to associate those sections with memory blocks and export
them to the userspace via sysfs because they cannot be onlined anyway.
This is currently expressed by for_device argument to arch_add_memory
which then makes sure to associate the given memory range with
ZONE_DEVICE. register_new_memory then relies on is_zone_device_section
to distinguish special memory hotplug from the regular one. While this
works now, later patches in this series want to move __add_zone outside
of arch_add_memory path so we have to come up with something else.
Add want_memblock down the __add_pages path and use it to control
whether the section->memblock association should be done.
arch_add_memory then just trivially want memblock for everything but
for_device hotplug.
remove_memory_section doesn't need is_zone_device_section either. We
can simply skip all the memblock specific cleanup if there is no
memblock for the given section.
This shouldn't introduce any functional change.
Link: http://lkml.kernel.org/r/20170515085827.16474-5-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull x86 mm updates from Ingo Molnar:
"The main changes in this cycle were:
- Continued work to add support for 5-level paging provided by future
Intel CPUs. In particular we switch the x86 GUP code to the generic
implementation. (Kirill A. Shutemov)
- Continued work to add PCID CPU support to native kernels as well.
In this round most of the focus is on reworking/refreshing the TLB
flush infrastructure for the upcoming PCID changes. (Andy
Lutomirski)"
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
x86/mm: Delete a big outdated comment about TLB flushing
x86/mm: Don't reenter flush_tlb_func_common()
x86/KASLR: Fix detection 32/64 bit bootloaders for 5-level paging
x86/ftrace: Exclude functions in head64.c from function-tracing
x86/mmap, ASLR: Do not treat unlimited-stack tasks as legacy mmap
x86/mm: Remove reset_lazy_tlbstate()
x86/ldt: Simplify the LDT switching logic
x86/boot/64: Put __startup_64() into .head.text
x86/mm: Add support for 5-level paging for KASLR
x86/mm: Make kernel_physical_mapping_init() support 5-level paging
x86/mm: Add sync_global_pgds() for configuration with 5-level paging
x86/boot/64: Add support of additional page table level during early boot
x86/boot/64: Rename init_level4_pgt and early_level4_pgt
x86/boot/64: Rewrite startup_64() in C
x86/boot/compressed: Enable 5-level paging during decompression stage
x86/boot/efi: Define __KERNEL32_CS GDT on 64-bit configurations
x86/boot/efi: Fix __KERNEL_CS definition of GDT entry on 64-bit configurations
x86/boot/efi: Cleanup initialization of GDT entries
x86/asm: Fix comment in return_from_SYSCALL_64()
x86/mm/gup: Switch GUP to the generic get_user_page_fast() implementation
...
Since commit:
af2cf278ef ("x86/mm/hotplug: Don't remove PGD entries in remove_pagetable()")
we no longer free PUDs so that we do not have to synchronize
all PGDs on hot-remove/vfree().
But the new 5-level page table patchset reverted that for 4-level
page tables, in the following commit:
f2a6a70501: ("x86: Convert the rest of the code to support p4d_t")
This patch restores the damage and disables free_pud() if we are in the
4-level page table case, thus avoiding BUG_ON() after hot-remove.
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
[ Clarified the changelog and the code comments. ]
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170624180514.3821-1-jglisse@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This basically restores slightly modified version of original
sync_global_pgds() which we had before folded p4d was introduced.
The only modification is protection against 'addr' overflow.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
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: 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/20170606113133.22974-11-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 fixes from Ingo Molnar:
"Misc fixes:
- two boot crash fixes
- unwinder fixes
- kexec related kernel direct mappings enhancements/fixes
- more Clang support quirks
- minor cleanups
- Documentation fixes"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/intel_rdt: Fix a typo in Documentation
x86/build: Don't add -maccumulate-outgoing-args w/o compiler support
x86/boot/32: Fix UP boot on Quark and possibly other platforms
x86/mm/32: Set the '__vmalloc_start_set' flag in initmem_init()
x86/kexec/64: Use gbpages for identity mappings if available
x86/mm: Add support for gbpages to kernel_ident_mapping_init()
x86/boot: Declare error() as noreturn
x86/mm/kaslr: Use the _ASM_MUL macro for multiplication to work around Clang incompatibility
x86/mm: Fix boot crash caused by incorrect loop count calculation in sync_global_pgds()
x86/asm: Don't use RBP as a temporary register in csum_partial_copy_generic()
x86/microcode/AMD: Remove redundant NULL check on mc
set_memory_* functions have moved to set_memory.h. Switch to this
explicitly.
Link: http://lkml.kernel.org/r/1488920133-27229-6-git-send-email-labbott@redhat.com
Signed-off-by: Laura Abbott <labbott@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Moyer reported that on his system with two memory regions 0~64G and
1T~1T+192G, and kernel option "memmap=192G!1024G" added, enabling KASLR
will make the system hang intermittently during boot. While adding 'nokaslr'
won't.
The back trace is:
Oops: 0000 [#1] SMP
RIP: memcpy_erms()
[ .... ]
Call Trace:
pmem_rw_page()
bdev_read_page()
do_mpage_readpage()
mpage_readpages()
blkdev_readpages()
__do_page_cache_readahead()
force_page_cache_readahead()
page_cache_sync_readahead()
generic_file_read_iter()
blkdev_read_iter()
__vfs_read()
vfs_read()
SyS_read()
entry_SYSCALL_64_fastpath()
This crash happens because the for loop count calculation in sync_global_pgds()
is not correct. When a mapping area crosses PGD entries, we should
calculate the starting address of region which next PGD covers and assign
it to next for loop count, but not add PGDIR_SIZE directly. The old
code works right only if the mapping area is an exact multiple of PGDIR_SIZE,
otherwize the end region could be skipped so that it can't be synchronized
to all other processes from kernel PGD init_mm.pgd.
In Jeff's system, emulated pmem area [1024G, 1216G) is smaller than
PGDIR_SIZE. While 'nokaslr' works because PAGE_OFFSET is 1T aligned, it
makes this area be mapped inside one PGD entry. With KASLR enabled,
this area could cross two PGD entries, then the next PGD entry won't
be synced to all other processes. That is why we saw empty PGD.
Fix it.
Reported-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
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: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jinbum Park <jinb.park7@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.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>
Cc: Yasuaki Ishimatsu <yasu.isimatu@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1493864747-8506-1-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
remove_pagetable() does page walk using p*d_page_vaddr() plus cast.
It's not canonical approach -- we usually use p*d_offset() for that.
It works fine as long as all page table levels are present. We broke the
invariant by introducing folded p4d page table level.
As result, remove_pagetable() interprets PMD as PUD and it leads to
crash:
BUG: unable to handle kernel paging request at ffff880300000000
IP: memchr_inv+0x60/0x110
PGD 317d067
P4D 317d067
PUD 3180067
PMD 33f102067
PTE 8000000300000060
Let's fix this by using p*d_offset() instead of p*d_page_vaddr() for
page walk.
Reported-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Fixes: f2a6a70501 ("x86: Convert the rest of the code to support p4d_t")
Link: http://lkml.kernel.org/r/20170425092557.21852-1-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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>
This patch converts x86 to use proper folding of a new (fifth) page table level
with <asm-generic/pgtable-nop4d.h>.
That's a bit of a kitchen sink patch, but I don't see how to split it further
without hurting bisectability.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
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: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170317185515.8636-7-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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>
To identify that pages of page table are allocated from bootmem
allocator, magic number sets to page->lru.next.
But page->lru list is initialized in reserve_bootmem_region(). So when
calling free_pagetable(), the function cannot find the magic number of
pages. And free_pagetable() frees the pages by free_reserved_page() not
put_page_bootmem().
But if the pages are allocated from bootmem allocator and used as page
table, the pages have private flag. So before freeing the pages, we
should clear the private flag by put_page_bootmem().
Before applying the commit 7bfec6f47b ("mm, page_alloc: check multiple
page fields with a single branch"), we could find the following visible
issue:
BUG: Bad page state in process kworker/u1024:1
page:ffffea103cfd8040 count:0 mapcount:0 mappi
flags: 0x6fffff80000800(private)
page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
bad because of flags: 0x800(private)
<snip>
Call Trace:
[...] dump_stack+0x63/0x87
[...] bad_page+0x114/0x130
[...] free_pages_prepare+0x299/0x2d0
[...] free_hot_cold_page+0x31/0x150
[...] __free_pages+0x25/0x30
[...] free_pagetable+0x6f/0xb4
[...] remove_pagetable+0x379/0x7ff
[...] vmemmap_free+0x10/0x20
[...] sparse_remove_one_section+0x149/0x180
[...] __remove_pages+0x2e9/0x4f0
[...] arch_remove_memory+0x63/0xc0
[...] remove_memory+0x8c/0xc0
[...] acpi_memory_device_remove+0x79/0xa5
[...] acpi_bus_trim+0x5a/0x8d
[...] acpi_bus_trim+0x38/0x8d
[...] acpi_device_hotplug+0x1b7/0x418
[...] acpi_hotplug_work_fn+0x1e/0x29
[...] process_one_work+0x152/0x400
[...] worker_thread+0x125/0x4b0
[...] kthread+0xd8/0xf0
[...] ret_from_fork+0x22/0x40
And the issue still silently occurs.
Until freeing the pages of page table allocated from bootmem allocator,
the page->freelist is never used. So the patch sets magic number to
page->freelist instead of page->lru.next.
[isimatu.yasuaki@jp.fujitsu.com: fix merge issue]
Link: http://lkml.kernel.org/r/722b1cc4-93ac-dd8b-2be2-7a7e313b3b0b@gmail.com
Link: http://lkml.kernel.org/r/2c29bd9f-5b67-02d0-18a3-8828e78bbb6f@gmail.com
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
So there's a number of constants that start with "E820" but which
are not types - these create a confusing mixture when seen together
with 'enum e820_type' values:
E820MAP
E820NR
E820_X_MAX
E820MAX
To better differentiate the 'enum e820_type' values prefix them
with E820_TYPE_.
No change in functionality.
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>
The 'any' and 'all' are modified to the 'mapped' concept, so move them last in the name.
No change in functionality.
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>
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>
Since commit af2cf278ef ("x86/mm/hotplug: Don't remove PGD entries in
remove_pagetable()") there are no callers of sync_global_pgds() which set
the 'removed' argument to 1.
Remove the argument and the related conditionals in the function.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Link: http://lkml.kernel.org/r/20161214234403.137556-1-kirill.shutemov@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Pull x86 header cleanups from Ingo Molnar:
"This tree is a cleanup of the x86 tree reducing spurious uses of
module.h - which should improve build performance a bit"
* 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, crypto: Restore MODULE_LICENSE() to glue_helper.c so it loads
x86/apic: Remove duplicated include from probe_64.c
x86/ce4100: Remove duplicated include from ce4100.c
x86/headers: Include spinlock_types.h in x8664_ksyms_64.c for missing spinlock_t
x86/platform: Delete extraneous MODULE_* tags fromm ts5500
x86: Audit and remove any remaining unnecessary uses of module.h
x86/kvm: Audit and remove any unnecessary uses of module.h
x86/xen: Audit and remove any unnecessary uses of module.h
x86/platform: Audit and remove any unnecessary uses of module.h
x86/lib: Audit and remove any unnecessary uses of module.h
x86/kernel: Audit and remove any unnecessary uses of module.h
x86/mm: Audit and remove any unnecessary uses of module.h
x86: Don't use module.h just for AUTHOR / LICENSE tags
Pull x86 boot updates from Ingo Molnar:
"The main changes:
- add initial commits to randomize kernel memory section virtual
addresses, enabled via a new kernel option: RANDOMIZE_MEMORY
(Thomas Garnier, Kees Cook, Baoquan He, Yinghai Lu)
- enhance KASLR (RANDOMIZE_BASE) physical memory randomization (Kees
Cook)
- EBDA/BIOS region boot quirk cleanups (Andy Lutomirski, Ingo Molnar)
- misc cleanups/fixes"
* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot: Simplify EBDA-vs-BIOS reservation logic
x86/boot: Clarify what x86_legacy_features.reserve_bios_regions does
x86/boot: Reorganize and clean up the BIOS area reservation code
x86/mm: Do not reference phys addr beyond kernel
x86/mm: Add memory hotplug support for KASLR memory randomization
x86/mm: Enable KASLR for vmalloc memory regions
x86/mm: Enable KASLR for physical mapping memory regions
x86/mm: Implement ASLR for kernel memory regions
x86/mm: Separate variable for trampoline PGD
x86/mm: Add PUD VA support for physical mapping
x86/mm: Update physical mapping variable names
x86/mm: Refactor KASLR entropy functions
x86/KASLR: Fix boot crash with certain memory configurations
x86/boot/64: Add forgotten end of function marker
x86/KASLR: Allow randomization below the load address
x86/KASLR: Extend kernel image physical address randomization to addresses larger than 4G
x86/KASLR: Randomize virtual address separately
x86/KASLR: Clarify identity map interface
x86/boot: Refuse to build with data relocations
x86/KASLR, x86/power: Remove x86 hibernation restrictions
So when memory hotplug removes a piece of physical memory from pagetable
mappings, it also frees the underlying PGD entry.
This complicates PGD management, so don't do this. We can keep the
PGD mapped and the PUD table all clear - it's only a single 4K page
per 512 GB of memory hotplugged.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
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: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <Waiman.Long@hp.com>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/064ff6c7275734537f969e876f6cd0baa954d2cc.1468527351.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.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>
The page table manipulation code seems to have grown a couple of
sites that are looking for empty PTEs. Just in case one of these
entries got a stray bit set, use pte_none() instead of checking
for a zero pte_val().
The use pte_same() makes me a bit nervous. If we were doing a
pte_same() check against two cleared entries and one of them had
a stray bit set, it might fail the pte_same() check. But, I
don't think we ever _do_ pte_same() for cleared entries. It is
almost entirely used for checking for races in fault-in paths.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
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: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: dave.hansen@intel.com
Cc: linux-mm@kvack.org
Cc: mhocko@suse.com
Link: http://lkml.kernel.org/r/20160708001915.813703D9@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Minor change that allows early boot physical mapping of PUD level virtual
addresses. The current implementation expects the virtual address to be
PUD aligned. For KASLR memory randomization, we need to be able to
randomize the offset used on the PUD table.
It has no impact on current usage.
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
Cc: Alexander Popov <alpopov@ptsecurity.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/1466556426-32664-4-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Change the variable names in kernel_physical_mapping_init() and related
functions to correctly reflect physical and virtual memory addresses.
Also add comments on each function to describe usage and alignment
constraints.
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
Cc: Alexander Popov <alpopov@ptsecurity.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/1466556426-32664-3-git-send-email-keescook@chromium.org
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
...
In order to support on-demand page table creation when moving the
kernel for KASLR, we need to use kernel_ident_mapping_init() in the
decompression code.
This splits it out into its own file for use outside of init_64.c.
Additionally, checking for __pa/__va defines is added since they
need to be overridden in the decompression code.
[kees: rewrote changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.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: Vivek Goyal <vgoyal@redhat.com>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462572095-11754-3-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 cumulative effect of the following two commits:
bdee237c03 ("x86: mm: Use 2GB memory block size on large-memory x86-64 systems")
982792c782 ("x86, mm: probe memory block size for generic x86 64bit")
... is some pretty convoluted code.
The first commit also removed code for the UV case without stated reason,
which might lead to unexpected change in behavior.
This commit has no other (intended) functional change; just seeks to simplify
and make the code more understandable, beyond restoring the UV behavior.
The whole section with the "tail size" doesn't seem to be
reachable, since both the >= 64GB and < 64GB case return, so it
was removed.
Signed-off-by: Seth Jennings <sjennings@variantweb.net>
Cc: Daniel J Blueman <daniel@numascale.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/1448902063-18885-1-git-send-email-sjennings@variantweb.net
[ Rewrote the title and changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In support of providing struct page for large persistent memory
capacities, use struct vmem_altmap to change the default policy for
allocating memory for the memmap array. The default vmemmap_populate()
allocates page table storage area from the page allocator. Given
persistent memory capacities relative to DRAM it may not be feasible to
store the memmap in 'System Memory'. Instead vmem_altmap represents
pre-allocated "device pages" to satisfy vmemmap_alloc_block_buf()
requests.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: kbuild test robot <lkp@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1/ Add support for the ACPI 6.0 NFIT hot add mechanism to process
updates of the NFIT at runtime.
2/ Teach the coredump implementation how to filter out DAX mappings.
3/ Introduce NUMA hints for allocations made by the pmem driver, and as
a side effect all devm allocations now hint their NUMA node by
default.
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Merge tag 'libnvdimm-for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"Outside of the new ACPI-NFIT hot-add support this pull request is more
notable for what it does not contain, than what it does. There were a
handful of development topics this cycle, dax get_user_pages, dax
fsync, and raw block dax, that need more more iteration and will wait
for 4.5.
The patches to make devm and the pmem driver NUMA aware have been in
-next for several weeks. The hot-add support has not, but is
contained to the NFIT driver and is passing unit tests. The coredump
support is straightforward and was looked over by Jeff. All of it has
received a 0day build success notification across 107 configs.
Summary:
- Add support for the ACPI 6.0 NFIT hot add mechanism to process
updates of the NFIT at runtime.
- Teach the coredump implementation how to filter out DAX mappings.
- Introduce NUMA hints for allocations made by the pmem driver, and
as a side effect all devm allocations now hint their NUMA node by
default"
* tag 'libnvdimm-for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
coredump: add DAX filtering for FDPIC ELF coredumps
coredump: add DAX filtering for ELF coredumps
acpi: nfit: Add support for hot-add
nfit: in acpi_nfit_init, break on a 0-length table
pmem, memremap: convert to numa aware allocations
devm_memremap_pages: use numa_mem_id
devm: make allocations numa aware by default
devm_memremap: convert to return ERR_PTR
devm_memunmap: use devres_release()
pmem: kill memremap_pmem()
x86, mm: quiet arch_add_memory()
Pull x86 mm changes from Ingo Molnar:
"The main changes are: continued PAT work by Toshi Kani, plus a new
boot time warning about insecure RWX kernel mappings, by Stephen
Smalley.
The new CONFIG_DEBUG_WX=y warning is marked default-y if
CONFIG_DEBUG_RODATA=y is already eanbled, as a special exception, as
these bugs are hard to notice and this check already found several
live bugs"
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Warn on W^X mappings
x86/mm: Fix no-change case in try_preserve_large_page()
x86/mm: Fix __split_large_page() to handle large PAT bit
x86/mm: Fix try_preserve_large_page() to handle large PAT bit
x86/mm: Fix gup_huge_p?d() to handle large PAT bit
x86/mm: Fix slow_virt_to_phys() to handle large PAT bit
x86/mm: Fix page table dump to show PAT bit
x86/asm: Add pud_pgprot() and pmd_pgprot()
x86/asm: Fix pud/pmd interfaces to handle large PAT bit
x86/asm: Add pud/pmd mask interfaces to handle large PAT bit
x86/asm: Move PUD_PAGE macros to page_types.h
x86/vdso32: Define PGTABLE_LEVELS to 32bit VDSO
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>
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>
The enabler / disabler is pretty simple, just use the
provided wrappers, this lets us easily relate the variable
to the associated Kconfig entry.
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: JBeulich@suse.com
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: julia.lawall@lip6.fr
Link: http://lkml.kernel.org/r/1425518654-3403-5-git-send-email-mcgrof@do-not-panic.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 vdso updates from Ingo Molnar:
"Various vDSO updates from Andy Lutomirski, mostly cleanups and
reorganization to improve maintainability, but also some
micro-optimizations and robustization changes"
* 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86_64/vsyscall: Restore orig_ax after vsyscall seccomp
x86_64: Add a comment explaining the TASK_SIZE_MAX guard page
x86_64,vsyscall: Make vsyscall emulation configurable
x86_64, vsyscall: Rewrite comment and clean up headers in vsyscall code
x86_64, vsyscall: Turn vsyscalls all the way off when vsyscall==none
x86,vdso: Use LSL unconditionally for vgetcpu
x86: vdso: Fix build with older gcc
x86_64/vdso: Clean up vgetcpu init and merge the vdso initcalls
x86_64/vdso: Remove jiffies from the vvar page
x86/vdso: Make the PER_CPU segment 32 bits
x86/vdso: Make the PER_CPU segment start out accessed
x86/vdso: Change the PER_CPU segment to use struct desc_struct
x86_64/vdso: Move getcpu code from vsyscall_64.c to vdso/vma.c
x86_64/vsyscall: Move all of the gate_area code to vsyscall_64.c
Pull x86 mm tree changes from Ingo Molnar:
"The biggest change is full PAT support from Jürgen Gross:
The x86 architecture offers via the PAT (Page Attribute Table) a
way to specify different caching modes in page table entries. The
PAT MSR contains 8 entries each specifying one of 6 possible cache
modes. A pte references one of those entries via 3 bits:
_PAGE_PAT, _PAGE_PWT and _PAGE_PCD.
The Linux kernel currently supports only 4 different cache modes.
The PAT MSR is set up in a way that the setting of _PAGE_PAT in a
pte doesn't matter: the top 4 entries in the PAT MSR are the same
as the 4 lower entries.
This results in the kernel not supporting e.g. write-through mode.
Especially this cache mode would speed up drivers of video cards
which now have to use uncached accesses.
OTOH some old processors (Pentium) don't support PAT correctly and
the Xen hypervisor has been using a different PAT MSR configuration
for some time now and can't change that as this setting is part of
the ABI.
This patch set abstracts the cache mode from the pte and introduces
tables to translate between cache mode and pte bits (the default
cache mode "write back" is hard-wired to PAT entry 0). The tables
are statically initialized with values being compatible to old
processors and current usage. As soon as the PAT MSR is changed
(or - in case of Xen - is read at boot time) the tables are changed
accordingly. Requests of mappings with special cache modes are
always possible now, in case they are not supported there will be a
fallback to a compatible but slower mode.
Summing it up, this patch set adds the following features:
- capability to support WT and WP cache modes on processors with
full PAT support
- processors with no or uncorrect PAT support are still working as
today, even if WT or WP cache mode are selected by drivers for
some pages
- reduction of Xen special handling regarding cache mode
Another change is a boot speedup on ridiculously large RAM systems,
plus other smaller fixes"
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
x86: mm: Move PAT only functions to mm/pat.c
xen: Support Xen pv-domains using PAT
x86: Enable PAT to use cache mode translation tables
x86: Respect PAT bit when copying pte values between large and normal pages
x86: Support PAT bit in pagetable dump for lower levels
x86: Clean up pgtable_types.h
x86: Use new cache mode type in memtype related functions
x86: Use new cache mode type in mm/ioremap.c
x86: Use new cache mode type in setting page attributes
x86: Remove looking for setting of _PAGE_PAT_LARGE in pageattr.c
x86: Use new cache mode type in track_pfn_remap() and track_pfn_insert()
x86: Use new cache mode type in mm/iomap_32.c
x86: Use new cache mode type in asm/pgtable.h
x86: Use new cache mode type in arch/x86/mm/init_64.c
x86: Use new cache mode type in arch/x86/pci
x86: Use new cache mode type in drivers/video/fbdev/vermilion
x86: Use new cache mode type in drivers/video/fbdev/gbefb.c
x86: Use new cache mode type in include/asm/fb.h
x86: Make page cache mode a real type
x86: mm: Use 2GB memory block size on large-memory x86-64 systems
...
When setting up permissions on kernel memory at boot, the end of the
PMD that was split from bss remained executable. It should be NX like
the rest. This performs a PMD alignment instead of a PAGE alignment to
get the correct span of memory.
Before:
---[ High Kernel Mapping ]---
...
0xffffffff8202d000-0xffffffff82200000 1868K RW GLB NX pte
0xffffffff82200000-0xffffffff82c00000 10M RW PSE GLB NX pmd
0xffffffff82c00000-0xffffffff82df5000 2004K RW GLB NX pte
0xffffffff82df5000-0xffffffff82e00000 44K RW GLB x pte
0xffffffff82e00000-0xffffffffc0000000 978M pmd
After:
---[ High Kernel Mapping ]---
...
0xffffffff8202d000-0xffffffff82200000 1868K RW GLB NX pte
0xffffffff82200000-0xffffffff82e00000 12M RW PSE GLB NX pmd
0xffffffff82e00000-0xffffffffc0000000 978M pmd
[ tglx: Changed it to roundup(_brk_end, PMD_SIZE) and added a comment.
We really should unmap the reminder along with the holes
caused by init,initdata etc. but thats a different issue ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20141114194737.GA3091@www.outflux.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
On large-memory x86-64 systems of 64GB or more with memory hot-plug
enabled, use a 2GB memory block size. Eg with 64GB memory, this reduces
the number of directories in /sys/devices/system/memory from 512 to 32,
making it more manageable, and reducing the creation time accordingly.
This caveat is that the memory can't be offlined (for hotplug or
otherwise) with the finer default 128MB granularity, but this is
unimportant due to the high memory densities generally used with such
large-memory systems, where eg a single DIMM is the order of 16GB.
Signed-off-by: Daniel J Blueman <daniel@numascale.com>
Cc: Steffen Persvold <sp@numascale.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Link: http://lkml.kernel.org/r/1415089784-28779-4-git-send-email-daniel@numascale.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
