Star64_linux/mm
Ard Biesheuvel 825c43f50e kmap_local: don't assume kmap PTEs are linear arrays in memory
The kmap_local conversion broke the ARM architecture, because the new
code assumes that all PTEs used for creating kmaps form a linear array
in memory, and uses array indexing to look up the kmap PTE belonging to
a certain kmap index.

On ARM, this cannot work, not only because the PTE pages may be
non-adjacent in memory, but also because ARM/!LPAE interleaves hardware
entries and extended entries (carrying software-only bits) in a way that
is not compatible with array indexing.

Fortunately, this only seems to affect configurations with more than 8
CPUs, due to the way the per-CPU kmap slots are organized in memory.

Work around this by permitting an architecture to set a Kconfig symbol
that signifies that the kmap PTEs do not form a lineary array in memory,
and so the only way to locate the appropriate one is to walk the page
tables.

Link: https://lore.kernel.org/linux-arm-kernel/20211026131249.3731275-1-ardb@kernel.org/
Link: https://lkml.kernel.org/r/20211116094737.7391-1-ardb@kernel.org
Fixes: 2a15ba82fa ("ARM: highmem: Switch to generic kmap atomic")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reported-by: Quanyang Wang <quanyang.wang@windriver.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-20 10:35:54 -08:00
..
damon mm/damon/dbgfs: fix missed use of damon_dbgfs_lock 2021-11-20 10:35:54 -08:00
kasan kasan: add kasan mode messages when kasan init 2021-11-11 09:34:35 -08:00
kfence
backing-dev.c
balloon_compaction.c
bootmem_info.c
cleancache.c
cma.c
cma.h
cma_debug.c
cma_sysfs.c
compaction.c
debug.c
debug_page_ref.c
debug_vm_pgtable.c
dmapool.c
early_ioremap.c
fadvise.c
failslab.c
filemap.c
folio-compat.c
frontswap.c
gup.c
gup_test.c
gup_test.h
highmem.c kmap_local: don't assume kmap PTEs are linear arrays in memory 2021-11-20 10:35:54 -08:00
hmm.c
huge_memory.c
hugetlb.c hugetlb, userfaultfd: fix reservation restore on userfaultfd error 2021-11-20 10:35:54 -08:00
hugetlb_cgroup.c
hugetlb_vmemmap.c
hugetlb_vmemmap.h
hwpoison-inject.c
init-mm.c
internal.h
interval_tree.c
io-mapping.c
ioremap.c
Kconfig kmap_local: don't assume kmap PTEs are linear arrays in memory 2021-11-20 10:35:54 -08:00
Kconfig.debug
khugepaged.c
kmemleak.c
ksm.c
list_lru.c
maccess.c
madvise.c
Makefile
mapping_dirty_helpers.c
memblock.c
memcontrol.c mm: unexport {,un}lock_page_memcg 2021-11-11 09:34:35 -08:00
memfd.c
memory-failure.c Revert "mm: shmem: don't truncate page if memory failure happens" 2021-11-13 12:03:03 -08:00
memory.c
memory_hotplug.c
mempolicy.c
mempool.c
memremap.c
memtest.c
migrate.c mm/migrate.c: remove MIGRATE_PFN_LOCKED 2021-11-11 09:34:35 -08:00
mincore.c
mlock.c
mm_init.c
mmap.c
mmap_lock.c
mmu_gather.c
mmu_notifier.c
mmzone.c
mprotect.c
mremap.c
msync.c
nommu.c
oom_kill.c
page-writeback.c
page_alloc.c
page_counter.c
page_ext.c
page_idle.c
page_io.c
page_isolation.c
page_owner.c
page_poison.c
page_reporting.c
page_reporting.h
page_vma_mapped.c
pagewalk.c
percpu-internal.h
percpu-km.c
percpu-stats.c
percpu-vm.c
percpu.c
pgalloc-track.h
pgtable-generic.c
process_vm_access.c
ptdump.c
readahead.c
rmap.c
rodata_test.c
secretmem.c
shmem.c Revert "mm: shmem: don't truncate page if memory failure happens" 2021-11-13 12:03:03 -08:00
shuffle.c
shuffle.h
slab.c mm: emit the "free" trace report before freeing memory in kmem_cache_free() 2021-11-20 10:35:54 -08:00
slab.h mm: kmemleak: slob: respect SLAB_NOLEAKTRACE flag 2021-11-20 10:35:54 -08:00
slab_common.c
slob.c mm: emit the "free" trace report before freeing memory in kmem_cache_free() 2021-11-20 10:35:54 -08:00
slub.c mm: emit the "free" trace report before freeing memory in kmem_cache_free() 2021-11-20 10:35:54 -08:00
sparse-vmemmap.c
sparse.c
swap.c mm/swap.c:put_pages_list(): reinitialise the page list 2021-11-20 10:35:54 -08:00
swap_cgroup.c
swap_slots.c
swap_state.c
swapfile.c
truncate.c
usercopy.c
userfaultfd.c Revert "mm: shmem: don't truncate page if memory failure happens" 2021-11-13 12:03:03 -08:00
util.c
vmacache.c
vmalloc.c
vmpressure.c
vmscan.c
vmstat.c
workingset.c
z3fold.c
zbud.c
zpool.c
zsmalloc.c
zswap.c