linux/arch/arm64
Ard Biesheuvel 24cc61d8cb arm64: memblock: don't permit memblock resizing until linear mapping is up
Bhupesh reports that having numerous memblock reservations at early
boot may result in the following crash:

  Unable to handle kernel paging request at virtual address ffff80003ffe0000
  ...
  Call trace:
   __memcpy+0x110/0x180
   memblock_add_range+0x134/0x2e8
   memblock_reserve+0x70/0xb8
   memblock_alloc_base_nid+0x6c/0x88
   __memblock_alloc_base+0x3c/0x4c
   memblock_alloc_base+0x28/0x4c
   memblock_alloc+0x2c/0x38
   early_pgtable_alloc+0x20/0xb0
   paging_init+0x28/0x7f8

This is caused by the fact that we permit memblock resizing before the
linear mapping is up, and so the memblock_reserved() array is moved
into memory that is not mapped yet.

So let's ensure that this crash can no longer occur, by deferring to
call to memblock_allow_resize() to after the linear mapping has been
created.

Reported-by: Bhupesh Sharma <bhsharma@redhat.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-11-08 17:54:03 +00:00
..
boot ARM: SoC device tree updates for 4.20 2018-10-29 15:05:20 -07:00
configs arm64: defconfig: Enable some IPMI configs 2018-11-02 11:39:50 -07:00
crypto crypto: arm64/aes-blk - ensure XTS mask is always loaded 2018-10-12 14:20:45 +08:00
include arm64: mm: define NET_IP_ALIGN to 0 2018-11-08 17:50:26 +00:00
kernel arm64 2nd round of updates for 4.20: 2018-11-03 10:55:23 -07:00
kvm KVM updates for v4.20 2018-10-25 17:57:35 -07:00
lib arm64: lib: use C string functions with KASAN enabled 2018-10-26 16:25:18 -07:00
mm arm64: memblock: don't permit memblock resizing until linear mapping is up 2018-11-08 17:54:03 +00:00
net bpf, arm64: save 4 bytes in prologue when ebpf insns came from cbpf 2018-05-14 19:11:45 -07:00
xen arm64: mm: Add additional parameter to uaccess_ttbr0_disable 2018-01-17 13:57:49 +01:00
Kconfig mm: remove CONFIG_HAVE_MEMBLOCK 2018-10-31 08:54:15 -07:00
Kconfig.debug Kconfig: consolidate the "Kernel hacking" menu 2018-08-02 08:06:48 +09:00
Kconfig.platforms ARM: SoC platform updates for 4.20 2018-10-29 15:37:33 -07:00
Makefile arm64 2nd round of updates for 4.20: 2018-11-03 10:55:23 -07:00