Catalin Marinas 6d332747fa arm64: Fix potential race with hardware DBM in ptep_set_access_flags() ... In a system with DBM (dirty bit management) capable agents there is a possible race between a CPU executing ptep_set_access_flags() (maybe non-DBM capable) and a hardware update of the dirty state (clearing of PTE_RDONLY). The scenario: a) the pte is writable (PTE_WRITE set), clean (PTE_RDONLY set) and old (PTE_AF clear) b) ptep_set_access_flags() is called as a result of a read access and it needs to set the pte to writable, clean and young (PTE_AF set) c) a DBM-capable agent, as a result of a different write access, is marking the entry as young (setting PTE_AF) and dirty (clearing PTE_RDONLY) The current ptep_set_access_flags() implementation would set the PTE_RDONLY bit in the resulting value overriding the DBM update and losing the dirty state. This patch fixes such race by setting PTE_RDONLY to the most permissive (lowest value) of the current entry and the new one. Fixes: 66dbd6e61a ("arm64: Implement ptep_set_access_flags() for hardware AF/DBM") Cc: Will Deacon <will.deacon@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>		2017-08-04 13:26:11 +01:00
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cache.S
context.c
copypage.c
dma-mapping.c	dma-coherent: introduce interface for default DMA pool	2017-07-20 16:09:10 +02:00
dump.c
extable.c
fault.c	arm64: Fix potential race with hardware DBM in ptep_set_access_flags()	2017-08-04 13:26:11 +01:00
flush.c
hugetlbpage.c
init.c
ioremap.c
kasan_init.c	arm64/kasan: don't allocate extra shadow memory	2017-07-10 16:32:33 -07:00
Makefile
mmap.c	arm64/mmap: properly account for stack randomization in mmap_base	2017-07-12 16:26:03 -07:00
mmu.c	arm64: mmu: Place guard page after mapping of kernel image	2017-07-28 10:32:14 +01:00
numa.c	arm64/numa: Drop duplicate message	2017-07-20 17:03:53 +01:00
pageattr.c
pgd.c
physaddr.c
proc.S
ptdump_debugfs.c