Pull kmap updates from Thomas Gleixner:
"The new preemtible kmap_local() implementation:
- Consolidate all kmap_atomic() internals into a generic
implementation which builds the base for the kmap_local() API and
make the kmap_atomic() interface wrappers which handle the
disabling/enabling of preemption and pagefaults.
- Switch the storage from per-CPU to per task and provide scheduler
support for clearing mapping when scheduling out and restoring them
when scheduling back in.
- Merge the migrate_disable/enable() code, which is also part of the
scheduler pull request. This was required to make the kmap_local()
interface available which does not disable preemption when a
mapping is established. It has to disable migration instead to
guarantee that the virtual address of the mapped slot is the same
across preemption.
- Provide better debug facilities: guard pages and enforced
utilization of the mapping mechanics on 64bit systems when the
architecture allows it.
- Provide the new kmap_local() API which can now be used to cleanup
the kmap_atomic() usage sites all over the place. Most of the usage
sites do not require the implicit disabling of preemption and
pagefaults so the penalty on 64bit and 32bit non-highmem systems is
removed and quite some of the code can be simplified. A wholesale
conversion is not possible because some usage depends on the
implicit side effects and some need to be cleaned up because they
work around these side effects.
The migrate disable side effect is only effective on highmem
systems and when enforced debugging is enabled. On 64bit and 32bit
non-highmem systems the overhead is completely avoided"
* tag 'core-mm-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
ARM: highmem: Fix cache_is_vivt() reference
x86/crashdump/32: Simplify copy_oldmem_page()
io-mapping: Provide iomap_local variant
mm/highmem: Provide kmap_local*
sched: highmem: Store local kmaps in task struct
x86: Support kmap_local() forced debugging
mm/highmem: Provide CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP
mm/highmem: Provide and use CONFIG_DEBUG_KMAP_LOCAL
microblaze/mm/highmem: Add dropped #ifdef back
xtensa/mm/highmem: Make generic kmap_atomic() work correctly
mm/highmem: Take kmap_high_get() properly into account
highmem: High implementation details and document API
Documentation/io-mapping: Remove outdated blurb
io-mapping: Cleanup atomic iomap
mm/highmem: Remove the old kmap_atomic cruft
highmem: Get rid of kmap_types.h
xtensa/mm/highmem: Switch to generic kmap atomic
sparc/mm/highmem: Switch to generic kmap atomic
powerpc/mm/highmem: Switch to generic kmap atomic
nds32/mm/highmem: Switch to generic kmap atomic
...
The conversion to the generic kmap_atomic() implementation missed the fact
that xtensa's fixmap works bottom up while all other implementations work
top down. There is no real reason why xtensa needs to work that way.
Cure it by:
- Using the generic fix_to_virt()/virt_to_fix() functions which work top
down
- Adjusting the mapping defines
- Using the generic index calculation for the non cache aliasing case
- Making the cache colour offset reverse so the effective index is correct
While at it, remove the outdated and misleading comment above the fixmap
enum which originates from the initial copy&pasta of this code from i386.
[ Max: Fixed the off by one in the index calculation ]
Fixes: 629ed3f7da ("xtensa/mm/highmem: Switch to generic kmap atomic")
Reported-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Max Filippov <jcmvbkbc@gmail.com>
Link: https://lore.kernel.org/r/20201116193253.23875-1-jcmvbkbc@gmail.com
free_highpages() iterates over the free memblock regions in high
memory, and marks each page as available for the memory management
system.
Until commit cddb5ddf2b ("arm, xtensa: simplify initialization of
high memory pages") it rounded beginning of each region upwards and end of
each region downwards.
However, after that commit free_highmem() rounds the beginning and end of
each region downwards, and we may end up freeing a page that is
memblock_reserve()d, resulting in memory corruption.
Restore the original rounding of the region boundaries to avoid freeing
reserved pages.
Fixes: cddb5ddf2b ("arm, xtensa: simplify initialization of high memory pages")
Link: https://lore.kernel.org/r/20201029110334.4118-1-ardb@kernel.org/
Link: https://lore.kernel.org/r/20201031094345.6984-1-rppt@kernel.org
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Co-developed-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Pull dma-mapping updates from Christoph Hellwig:
- rework the non-coherent DMA allocator
- move private definitions out of <linux/dma-mapping.h>
- lower CMA_ALIGNMENT (Paul Cercueil)
- remove the omap1 dma address translation in favor of the common code
- make dma-direct aware of multiple dma offset ranges (Jim Quinlan)
- support per-node DMA CMA areas (Barry Song)
- increase the default seg boundary limit (Nicolin Chen)
- misc fixes (Robin Murphy, Thomas Tai, Xu Wang)
- various cleanups
* tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping: (63 commits)
ARM/ixp4xx: add a missing include of dma-map-ops.h
dma-direct: simplify the DMA_ATTR_NO_KERNEL_MAPPING handling
dma-direct: factor out a dma_direct_alloc_from_pool helper
dma-direct check for highmem pages in dma_direct_alloc_pages
dma-mapping: merge <linux/dma-noncoherent.h> into <linux/dma-map-ops.h>
dma-mapping: move large parts of <linux/dma-direct.h> to kernel/dma
dma-mapping: move dma-debug.h to kernel/dma/
dma-mapping: remove <asm/dma-contiguous.h>
dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h>
dma-contiguous: remove dma_contiguous_set_default
dma-contiguous: remove dev_set_cma_area
dma-contiguous: remove dma_declare_contiguous
dma-mapping: split <linux/dma-mapping.h>
cma: decrease CMA_ALIGNMENT lower limit to 2
firewire-ohci: use dma_alloc_pages
dma-iommu: implement ->alloc_noncoherent
dma-mapping: add new {alloc,free}_noncoherent dma_map_ops methods
dma-mapping: add a new dma_alloc_pages API
dma-mapping: remove dma_cache_sync
53c700: convert to dma_alloc_noncoherent
...
Merge dma-contiguous.h into dma-map-ops.h, after removing the comment
describing the contiguous allocator into kernel/dma/contigous.c.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Use correct symbol for the end of .rodata section when dumping virtual
memory layout. This fixes odd rodata size with XIP kernel.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
The xtensa free_initrd_mem() verifies that initrd is mapped and then
frees its memory using free_reserved_area().
The initrd is considered mapped when its memory was successfully reserved
with mem_reserve().
Resetting initrd_start to 0 in case of mem_reserve() failure allows to
switch to generic free_initrd_mem() implementation.
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Message-Id: <1563977432-8376-1-git-send-email-rppt@linux.ibm.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Patch series "provide a generic free_initmem implementation", v2.
Many architectures implement free_initmem() in exactly the same or very
similar way: they wrap the call to free_initmem_default() with sometimes
different 'poison' parameter.
These patches switch those architectures to use a generic implementation
that does free_initmem_default(POISON_FREE_INITMEM).
This was inspired by Christoph's patches for free_initrd_mem [1] and I
shamelessly copied changelog entries from his patches :)
[1] https://lore.kernel.org/lkml/20190213174621.29297-1-hch@lst.de/
This patch (of 2):
For most architectures free_initmem just a wrapper for the same
free_initmem_default(-1) call. Provide that as a generic implementation
marked __weak.
Link: http://lkml.kernel.org/r/1550515285-17446-2-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull Xtensa fixes and cleanups from Max Filippov:
- use ZONE_NORMAL instead of ZONE_DMA
- fix Image.elf build error caused by assignment of incorrect address
to the .note.Linux section
- clean up debug and property sections in the vmlinux.lds.S
* tag 'xtensa-20181101' of git://github.com/jcmvbkbc/linux-xtensa:
xtensa: clean up xtensa-specific property sections
xtensa: use DWARF_DEBUG in the vmlinux.lds.S
xtensa: add NOTES section to the linker script
xtensa: remove ZONE_DMA
ZONE_DMA is intended for magic < 32-bit pools (usually ISA DMA), which
isn't required on xtensa. Move all the non-highmem memory into
ZONE_NORMAL instead to match other architectures.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Xtensa memory initialization code frees high memory pages without
checking whether they are in the reserved memory regions or not. That
results in invalid value of totalram_pages and duplicate page usage by
CMA and highmem. It produces a bunch of BUGs at startup looking like
this:
BUG: Bad page state in process swapper pfn:70800
page:be60c000 count:0 mapcount:-127 mapping: (null) index:0x1
flags: 0x80000000()
raw: 80000000 00000000 00000001 ffffff80 00000000 be60c014 be60c014 0000000a
page dumped because: nonzero mapcount
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Tainted: G B 4.16.0-rc1-00015-g7928b2cbe55b-dirty #23
Stack:
bd839d33 00000000 00000018 ba97b64c a106578c bd839d70 be60c000 00000000
a1378054 bd86a000 00000003 ba97b64c a1066166 bd839da0 be60c000 ffe00000
a1066b58 bd839dc0 be504000 00000000 000002f4 bd838000 00000000 0000001e
Call Trace:
[<a1065734>] bad_page+0xac/0xd0
[<a106578c>] free_pages_check_bad+0x34/0x4c
[<a1066166>] __free_pages_ok+0xae/0x14c
[<a1066b58>] __free_pages+0x30/0x64
[<a1365de5>] init_cma_reserved_pageblock+0x35/0x44
[<a13682dc>] cma_init_reserved_areas+0xf4/0x148
[<a10034b8>] do_one_initcall+0x80/0xf8
[<a1361c16>] kernel_init_freeable+0xda/0x13c
[<a125b59d>] kernel_init+0x9/0xd0
[<a1004304>] ret_from_kernel_thread+0xc/0x18
Only free high memory pages that are not reserved.
Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Output virtual addresses and sizes occupied by the main kernel sections:
.text, .rodata, .data, .init and .bss.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Cover kernel addresses above 0x90000000 by the shadow map. Enable
HAVE_ARCH_KASAN when MMU is enabled. Provide kasan_early_init that fills
shadow map with writable copies of kasan_zero_page. Call
kasan_early_init right after mmu initialization in the setup_arch.
Provide kasan_init that allocates proper shadow map pages from the
memblock and puts these pages into the shadow map for addresses from
VMALLOC area to the end of KSEG. Call kasan_init right after memblock
initialization. Don't use KASAN for the boot code, MMU and KASAN
initialization and page fault handler. Make kernel stack size 4 times
larger when KASAN is enabled to avoid stack overflows.
GCC 7.3, 8 or newer is required to build the xtensa kernel with KASAN.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
The virtual address space between the page table and the VMALLOC region
is big enough to host KASAN shadow map and there's enough space between
the VMALLOC area and KSEG for the fixmap and kmap.
Move fixmap and kmap to the gap between VMALLOC area and KSEG, just
above the KSEG. Reorder entries in the kernel memory layout printing
code. Drop duplicate PGTABLE_START definition, use
XCHAL_PAGE_TABLE_VADDR instead.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Enable HAVE_DMA_CONTIGUOUS, reserve contiguous memory at bootmem_init,
use dma_alloc_from_contiguous and dma_release_from_contiguous in
xtensa_dma_alloc/free.
This allows for big contiguous DMA buffer allocation from designated
area configured in the device tree.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This allows reserving regions of physical memory from the device tree.
See Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
for more details.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Memblock is the standard kernel boot-time memory tracker/allocator. Use
it instead of the custom sysmem allocator. This allows using kmemleak,
CMA and device tree memory reservation.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
MMUv3 is able to support low memory bigger than 128MB.
Implement 256MB and 512MB KSEG layouts:
- add Kconfig selector for KSEG layout;
- add KSEG base address, size and alignment definitions to
arch/xtensa/include/asm/kmem_layout.h;
- use new definitions in TLB initialization;
- add build time memory map consistency checks.
See Documentation/xtensa/mmu.txt for the details of new memory layouts.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Create a header dedicated to memory layout definitions. Include it from
places where these definitions are needed.
Express vmalloc area address, VIRTUAL_MEMORY_ADDRESS and KERNELOFFSET
through KSEG address.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
noMMU configuration doesn't use special area for vmalloc allocations,
don't print it in the memory map.
PAGE_OFFSET is fixed to 0 in noMMU, use min_low_pfn and max_low_pfn for
lowmem range display.
Make all XCHAL_KSEG_* constants unsigned long for consistency with other
addresses.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Memory accounting code can't handle pages below
PLATFORM_DEFAULT_MEM_START. Reserve those pages if they exist.
When PLATFORM_DEFAULT_MEM_START is zero reserve one page at address 0 to
make sure that successfull memory allocations don't return NULL.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
When sysmem reservation occurs exactly at the end of an existing block
that block is deleted, because it is incorrectly included in the range
of memblocks to remove. Fix that by skipping such block.
Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Introduce fixmap area just below the vmalloc region. Use it for atomic
mapping of high memory pages.
High memory on cores with cache aliasing is not supported and is still
to be implemented. Fail build for such configurations for now.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Debug dump of physical memory configuration. Useful for inspection of
resulting memory map, esp. in the presence of memmap= kernel option.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This option is useful for reserving memory regions for secondary cores
in AMP configurations.
Implement the following memmap variants:
- memmap=nn[KMG]@ss[KMG]: force usage of a specific region of memory;
- memmap=nn[KMG]$ss[KMG]: mark specified memory as reserved;
- memmap=nn[KMG]: set end of memory.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Bootparam meminfo is a bootloader ABI, kernel meminfo is for the kernel
bookkeeping, keep them separate. Kernel doesn't care of memory region
types, so drop the type field and don't pass it to add_sysmem_bank.
Move kernel sysmem structures and prototypes to asm/sysmem.h and sysmem
variable and add_sysmem_bank to mm/init.c
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Change signature of free_reserved_area() according to Russell King's
suggestion to fix following build warnings:
arch/arm/mm/init.c: In function 'mem_init':
arch/arm/mm/init.c:603:2: warning: passing argument 1 of 'free_reserved_area' makes integer from pointer without a cast [enabled by default]
free_reserved_area(__va(PHYS_PFN_OFFSET), swapper_pg_dir, 0, NULL);
^
In file included from include/linux/mman.h:4:0,
from arch/arm/mm/init.c:15:
include/linux/mm.h:1301:22: note: expected 'long unsigned int' but argument is of type 'void *'
extern unsigned long free_reserved_area(unsigned long start, unsigned long end,
mm/page_alloc.c: In function 'free_reserved_area':
>> mm/page_alloc.c:5134:3: warning: passing argument 1 of 'virt_to_phys' makes pointer from integer without a cast [enabled by default]
In file included from arch/mips/include/asm/page.h:49:0,
from include/linux/mmzone.h:20,
from include/linux/gfp.h:4,
from include/linux/mm.h:8,
from mm/page_alloc.c:18:
arch/mips/include/asm/io.h:119:29: note: expected 'const volatile void *' but argument is of type 'long unsigned int'
mm/page_alloc.c: In function 'free_area_init_nodes':
mm/page_alloc.c:5030:34: warning: array subscript is below array bounds [-Warray-bounds]
Also address some minor code review comments.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: <sworddragon2@aol.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: David Howells <dhowells@redhat.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>
Remove heading and trailing spaces, trim trailing lines, and wrap lines
that are longer than 80 characters.
Signed-off-by: Chris Zankel <chris@zankel.net>
Cleanups:
- Include <asm/sections.h>,
- Remove the (different) extern declarations,
- Remove the no longer needed address-of ('&') operators,
- Use %p to format pointer differences.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
commit a2d063ac21 ("extable, core_kernel_data(): Make sure all archs
define _sdata") missed xtensa. Xtensa does have a start of data marker,
but calls it _fdata, causing
kernel/built-in.o:(.text+0x964): undefined reference to `_sdata'
_stext was already defined, but it was duplicated by _fdata.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
