linux/arch/arm64
Anshuman Khandual bf2b59f60e arm64/mm: Hold memory hotplug lock while walking for kernel page table dump
The arm64 page table dump code can race with concurrent modification of the
kernel page tables. When a leaf entries are modified concurrently, the dump
code may log stale or inconsistent information for a VA range, but this is
otherwise not harmful.

When intermediate levels of table are freed, the dump code will continue to
use memory which has been freed and potentially reallocated for another
purpose. In such cases, the dump code may dereference bogus addresses,
leading to a number of potential problems.

Intermediate levels of table may by freed during memory hot-remove,
which will be enabled by a subsequent patch. To avoid racing with
this, take the memory hotplug lock when walking the kernel page table.

Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-04 15:35:22 +00:00
..
boot ARMv8 Juno/Fast Models fix for v5.6 2020-02-11 14:47:09 -08:00
configs This pull request contains ARM64 defconfig changes for v5.6, please pull 2020-02-11 14:49:38 -08:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2020-01-28 15:38:56 -08:00
include arm64: memory: Add missing brackets to untagged_addr() macro 2020-02-19 13:41:33 +00:00
kernel arm64: time: Replace <linux/clk-provider.h> by <linux/of_clk.h> 2020-02-12 17:26:38 +00:00
kvm ARM: Cleanups and corner case fixes 2020-01-31 09:30:41 -08:00
lib Merge branch 'for-next/asm-annotations' into for-next/core 2020-01-22 11:34:21 +00:00
mm arm64/mm: Hold memory hotplug lock while walking for kernel page table dump 2020-03-04 15:35:22 +00:00
net
xen arm64: xen: Use modern annotations for assembly functions 2020-01-09 16:09:42 +00:00
Kbuild
Kconfig asm-generic/tlb: rename HAVE_RCU_TABLE_FREE 2020-02-04 03:05:26 +00:00
Kconfig.debug arm64: mm: convert mm/dump.c to use walk_page_range() 2020-02-04 03:05:25 +00:00
Kconfig.platforms i.MX SoC update for 5.5: 2019-11-06 07:46:42 -08:00
Makefile arm64: Turn "broken gas inst" into real config option 2020-01-15 16:35:12 +00:00